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Acute effects of smoking and high experimental exposure to environmental tobacco smoke (ETS) on the immune system
Abstract
Controversial results have been published on the immune response to cigarette smoking while the effects of exposure to environmental tobacco smoke (ETS) have not yet been reported. In a controlled study, acute effects of smoking and of a high environmental exposure to ETS on immunological parameters have been investigated. The study consisted of four experimental days, two control and two exposure days. On control days, 1 and 3, smokers (n = 5) and nonsmokers (n = 5) sat in an unventilated 45 m3 room for 8 h. On the exposure days, 2 and 4, each of the smokers smoked 24 cigarettes in 8 h, while the nonsmokers were exposed to the ETS generated by the smoking volunteers. Blood was drawn before and after each exposure session on all four experimental days for dosimetry of tobacco smoke exposure and determination of the immune response. Flow cytometry using monoclonal antibodies was used to determine CD3+ cells (whole T cells), CD19+ cells (B lymphocytes), CD16+ and CD56+ cells (natural killer cells), CD4+ cells (T-helper cells), CD8+ cells (T-suppressor cells), the CD4+/CD8+ (helper/suppressor ratio), and Fc receptors on granulocytes. Serum was analyzed for soluble CD14 receptors (sCD14), interleukin 1, interleukin 6 and prostaglandin E2 (PGE2). Functional stimulation assays were performed to determine the basal and induced level of reactive oxygen intermediate (ROI) production by polymorphic neutrophils. Exposure to tobacco smoke in both groups was confirmed by dosimetry of carboxyhemoglobin, plasma nicotine, and cotinine levels. In comparison to nonsmokers, smokers had elevated granulocyte cell counts, increased CD16+ and CD56+ cell levels and decreased CD3+ and CD19+ levels. Acute smoking, but not exposure to ETS, resulted in a slight decrease in the number of CD19+ cells and an increase in the number of granulocytes; the latter was restricted to one subject. Acute smoking and exposure to high experimental concentrations of ETS resulted in a slight increase in CD16+ and CD56+ cells. None of the changes determined in immunological parameters after either acute smoking or exposure to ETS reached statistical significance. Serum sCD14, cytokine and PGE2, functional stimulation of in vitro ROI production, and changes in Fc receptors were not affected by acute smoking or exposure to ETS. Although no clear guidelines exist to assess immunotoxicity in man, our data do not favor immunosuppression and the possibility of increased risk of infection in nonsmokers exposed to ETS under real-life conditions.
... In all cases, smoking patients exhibited reduced changes in probing depth and attachment loss compared with non-smoking patients. Payne et al., 1994Higashimoto et al., 1992Sauty et al., 1994Twigg et al., 1994Janson et al., 1995Payne et al., 1994Payne et al., 1994Pueringer et al., 1993Suzuki et al., 1993Aoshiba et al., 1994Aoshiba et al., 1994Hersey et al., 1983Ginns et al., 1985Hughes et al., 1 985;Phillips et al., 1985;Nair et al., 1990Hockertz et al., 1994 Francus et ai., 1 988 Sopori et al., 1989;Savage et al., 1991;Goud et a!., 1992Goud et al., 1993Francus et al., 1 988 Menard and Rola-Pleszczynski, 1987Petro et al., 1992Chang et al., 1990Johnson et al., 1990 a Smokeless tobacco. ...
... Similarly, animal models suggest that acute exposure to tobacco smoke induces an increase in the number of macrophages recovered in BALF, but no change in the number of macrophages in the peritoneum (Pessina et al., 1993). These data are in contrast to those from studies in human systems which indicate increased overall cellularity and increased numbers of macrophages in both the BALF and peripheral blood of smokers (Hoogsteden et al., 1991, Merchant et al., 1992Hockertz et al., 1994;McCrea et al., 1994;Schwartz and Weiss, 1994). Interestingly, it has been reported that the increase in cellularity of smoker BALF is resolved when smoking ceases (Skold et al., 1993). ...
... Studies of the effects of smoking and tobacco on the production of lipid mediators are not yet as conclusive as those on cytokine production. Although acute exposure to tobacco smoke induces an increase in the number of macrophages recovered in BALF from human subjects, the levels of prostaglandin E2 (PGE2) are similar in smoker and non-smoker BALF (Pueringer et al., 1993;Hockertz et al., 1994). Similarly, AM isolated from smokers and non-smokers produce similar levels of both spontaneous and LPS-induced PGE2 and leukotriene B4 (LTB4) (Pueringer et al., 1993;Suzuki et al., 1993). ...
This review summarizes the current data on the effects of smoking and tobacco on the immune system and its potential impact on periodontal health. Smokers are 2.5-6 times more likely to develop periodontal disease than non-smokers, and there is evidence for a direct correlation between the number of cigarettes smoked and the risk of developing disease. Tobacco users also tend to exhibit increased severity of periodontal disease. Direct correlations between tobacco use and increased attachment loss and pocket depth and reduced bone crest height have been reported.
Although the correlation between tobacco use and periodontal disease is quite strong, the role of tobacco in the pathogenesis of periodontal disease is uncertain. Recent studies indicate that one potential mechanism is that tobacco use exacerbates periodontal disease because it alters the immune response to periodontal pathogens. Indeed, smokers exhibit increased numbers of peripheral blood mononuclear phagocytes which appear to be functionally compromised. Inadequate phagocyte activity could reduce the clearance of pathogens from the oral cavity and thereby facilitate the development of periodontal disease Tobacco-exposed B- and T-lymphocytes exhibit reduced proliferative capacities which could limit the production of protective immunoglobulins against oral pathogens.
The risk factors for periodontal disease can be broadly classified as genetic, environmental, host-response factors, and host-related factors such as age. Tobacco, an environmental factor, undermines the host response and may facilitate the development and progression of periodontal disease. This review highlights the inter-relatedness of two of the risk factors associated with periodontal disease.
... Carcinogens found in cigarette smoke induce oncogenic mutations responsible for most lung cancers (1,2). Smoking affects the immune landscape of the lung and is generally associated with chronic airway inflammation (3)(4)(5)(6). This in turn can lead to tissue damage and immune dysfunction resulting from T cell exhaustion and compensatory engagement of immune suppression mechanisms (7) as seen in chronic obstructive pulmonary disease (COPD) (8), sarcoidosis (9), and Covid-19 (10). ...
Background
Bronchoalveolar lavage (BAL) is an underutilized tool in the search for pulmonary disease biomarkers. While leukocytes with effector and suppressor function play important roles in airway immunity and tumors, it remains unclear if frequencies and phenotypes of BAL leukocytes can be useful parameters in lung cancer studies and clinical trials. We therefore explored the utility of BAL leukocytes as a source of biomarkers interrogating the impact of smoking, a major lung cancer risk determinant, on pulmonary immunity.
Methods
In this ‘test case’ observational study, BAL samples from 119 donors undergoing lung cancer screening and biopsy procedures were evaluated by conventional and spectral flow cytometry to exemplify the comprehensive immune analyses possible with this biospecimen. Proportions of major leukocyte populations and phenotypic markers levels were found. Multivariate linear rank sum analysis considering age, sex, cancer diagnosis, and smoking status was performed.
Results
Significantly increased frequencies of myeloid derived suppressor cells and PD-L1-expressing macrophages were found in current and former smokers compared to never smokers. While cytotoxic CD8T cells and conventional CD4 helper T cell frequencies were significantly reduced in current and former smokers, expression of immune checkpoints PD-1 and LAG-3 as well as Tregs proportions were increased. Lastly, the cellularity, viability and the stability of several immune readouts under cryostorage suggested BAL samples are useful for correlative endpoints in clinical trials.
Conclusions
Smoking is associated with heightened markers of immune dysfunction, readily assayable in BAL, that may reflect a permissive environment for cancer development and progression in the airway.
... On the other hand, it has been linked to reduced CD16 NK cell counts [23,24]. As well another study has found elevated granulocyte cell counts and CD16 + -CD56 + cell counts [25]. Some studies found positive significant associations between smoking and the CD57 expression [26,27] although some others did not report such associations [28]. ...
Introduction:
Factors associated with the expression of oral squamous cell carcinoma (OSCC) biomarkers "CD16, CD57, TGF-β1, and MED15" are not assessed, except in few controversial studies of some of these biomarkers. This study aimed to highlight factors that can correlate with tumoral overexpression of these biomarkers.
Methods:
In this genetically-matched case-control study, biomarker expressions in all available OSCC tissues and their adjacent normal tissues at the National Tumor Center (n = 384 (4 biomarkers × (48 cancers + 48 controls))) were measured using qRT-PCR. Factors associated with tumoral overexpression of CD16, CD57, TGF-β1, and MED15 (compared to the benign control) were evaluated, using log-level multiple linear regressions and Spearman (α = 0.05).
Results:
Tumoral CD16 upregulation was observed in younger patients (β = -0.284, P=0.040) and cigarette smokers (β = 0.397, P=0.005). Tumoral CD57 was upregulated in males (β = 0.341, P=0.008), smokers (β = 0.401, P=0.002), and cases without vascular invasion (β = -0.242, P=0.042). Tumoral TGF-β1 was elevated in smokers (β = 0.452, P=0.001) and smaller tumors (β = -0.322, P=0.045). Tumoral MED15 was overexpressed in smokers (β = 0.295, P=0.036) and cases lacking perineural invasion (β = -0.394, P=0.007).
Conclusion:
As the most consistent finding, smoking might be positively associated with tumoral overexpression of all biomarkers. Tumoral increase in CD57 might be positively associated with metastasis while being negatively correlated with vascular and lymphatic invasion. Tumor size might be negatively associated with tumoral TGF-β1 expression.
... In spite of controversial reports, inflammatory cells, oxidative stress, and inflammatory mediators are the major contributors to smoking-related inflammation in humans. 1 The reported change in inflammatory cells included an increase in neutrophils in chronic and acute exposure to cigarette smoking in both peripheral blood and bronchoalveolar lavage fluid. [1][2][3][4][5] Accumulated evidence has also shown that the acute exposure to cigarette smoking can result in immediate increase in oxidative stress and reactive species. 1,6-8 Moreover, mediators of inflammation in humans as well as animal and in vitro models such as plasma neutrophil elastase and leukotrienes B 4 , D 4 , E 4 4,9,10 and inflammatory cytokines (such as TNF-α) 11 in acute smoking have also shown to be changed. ...
Background and objective: Cigarette smoking is a leading cause of a wide range of critical health problems such as cancers, especially those related to the respiratory system. Although studies are continuing on the smoking-related inflammatory responses, limited reports are there to explore how such responses can be affected by the smoking intensity. Therefore, the current communication aimed to shed light on how smoking and smoking intensity can affect some inflammatory and anti-inflammatory biomarkers.
Methods: A total of 159 subjects (108 smokers and 51 non-smokers) were enrolled in this cross-sectional study. Their sociodemographic, smoking intensity and blood samples were obtained and processed using approved methodologies. The blood plasma samples were used to quantify interleukin 6 (IL-6), IL-10, tumor necrosis factor-alpha (TNF-α), C-reactive protein, D-dimer, and ferritin by using ELISA. The gained data was then analyzed using GraphPad Prism software to assess the variations.
Results: Both IL-6 and TNF-α are elevated markedly (p
... inflammatory effect of carbon monoxide (6)(7)(8). ...
... It is also important to note that the known increasing effect that tobacco smoking/chewing has on OSCC. But it could not account for the difference in IL-6 levels between the cancer patients and the PMD subjects, as the numbers of smokers among these two groups were similar and moreover it is reported that smoking has no effect on IL-6 concentration (Hockertz et al., 1994;Chiu et al., 2011). ...
Aim
To assess the diagnostic utility of serum and salivary interleukin 6 (IL-6) levels in the differential diagnosis of potentially malignant lesions and conditions (PMLs/PMCs) and oral squamous cell carcinoma (OSCC) in a high oral cancer prevalence region.
Methods
After appropriate ethical clearance and informed consent, salivary and blood samples were collected from 100 participants in each group (OSCC, PMLs, and healthy controls). Serum and salivary IL-6 levels were measured by enzyme-linked immunosorbent assay and data were subjected to appropriate statistical analysis.
Results
Significant differences in IL-6 concentration were noted between OSCC and PML/C patients in both serum and saliva, with salivary levels being 2 to 3 fold higher than serum values in all the groups. Receiver operating characteristic curve analysis demonstrated 96% specificity and 99% sensitivity for salivary IL-6 in differentiating PML from OSCC.
Conclusions
The results of the present study suggest that the pro-inflammatory cytokine, IL-6, is elevated in the saliva of patients with OSSC compared to PMD and controls, and thus may prove to have diagnostic and/or prognostic significance.
... First, nicotine itself is converted to carcinogens (5) and also causes abnormal fetal development due to aberrant activation of acetylcholine receptors (6). Secondly, cigarette smoke contains particulates that activate immune cells (7,8) and also contain multiple polycyclic aromatic hydrocarbons (PAH) that are bioactivated to carcinogens in vivo (9). Thirdly, cigarettes contribute half of environmental exposure to cadmium, a carcinogenic metal ion (10). ...
Objective:
The aim of this study is to use high-resolution metabolomics (HRM) to identify metabolic pathways and networks associated with tobacco use in military personnel.
Methods:
Four hundred deidentified samples obtained from the Department of Defense Serum Repository were classified as tobacco users or nonusers according to cotinine content. HRM and bioinformatic methods were used to determine pathways and networks associated with classification.
Results:
Eighty individuals were classified as tobacco users compared with 320 nonusers on the basis of cotinine levels at least 10 ng/mL. Alterations in lipid and xenobiotic metabolism, and diverse effects on amino acid, sialic acid, and purine and pyrimidine metabolism were observed. Importantly, network analysis showed broad effects on metabolic associations not simply linked to well-defined pathways.
Conclusions:
Tobacco use has complex metabolic effects that must be considered in evaluation of deployment-associated environmental exposures in military personnel.
... Other inflammatory markers for e.g. CD19 positive B cells and the total number lymphocytes were also decreased during acute exposure to cigarette smoke 464,465 . However, in the chronic smoke exposure like that in my study showed increased lymphocytes in the peripheral blood in smokers. ...
Smoking is the major risk factor for COPD. Smoking also has systemic effects and is considered as one of the risk factors for metabolic syndrome (MeS). It is unclear whether it is smoking per se or the systemic effects of COPD that cause metabolic syndrome in smokers.
Smokers with and without COPD and non-smoking controls were studied by pulmonary function testing, skin prick tests, body composition, fasting glucose, CRP, and lipids analysis to diagnose MeS. This showed a gradual increase in prevalence of MeS, but with only difference between non-smokers on one hand and smokers with or without COPD on the other being significant. This suggested that smoking, rather than the systemic effect of COPD, was the cause of MeS.
All smokers were then grouped and smokers and non-smokers compared in respect of lung function, inflammatory markers (CRP, a series of inflammatory cytokines), insulin resistance, and body composition. Smokers had increased central obesity and total body fat, which is in contrast to the common belief that smoking reduces weight. Male smokers demonstrated increased abdominal fat, while females showed an increase in total body fat. FEV1 was reduced when comparing all smokers with MeS and those without MeS, and there was a greater reduction in males who had a greater prevalence of MeS, but had better quality of life even though they smoked more. However, whilst smokers with MeS had higher levels of insulin resistance, as measured by Homeostasis Model Assessment (HOMA-R), none of the plasma inflammatory markers, except for IL-12, was raised, suggesting that these indices of inflammation were not the reason for MeS.
Smoking is associated with a gradual decline in lung function in smokers with and without COPD. A previously recruited cohort of smokers with and without COPD and healthy non-smoking subjects were followed up over a period of 5 years. Amongst a whole series of measurements, including HRCT, measures of lung density/emphysema, only sputum neutrophilia (both absolute and percentage counts) predicted the annual decline in FEV1.
In summary, this study suggests that there is an increased prevalence of MeS in smokers associated with insulin resistance caused by smoking but it fails to show an association between MeS and COPD. Smoking is also associated with central obesity and increased body fat, contributing to a reduction in FEV1. Sputum neutrophilia, but not smoking pack years or lung HRCT measurements, predicts the annual FEV1 decline in smokers.
... Nicotine, one of the particulate components of tobacco smoke, has been shown to be carcinogenic (5), but its genotoxic potential is debatable (2,13). In addition, nicotine has direct toxic effects on local tissues, i.e. oral mucosa (14), and circulating cells, i.e. leucocytes (15). A number of in vivo studies have been performed to ascertain the activity of tobacco and/or nicotine, with mice, rats and hamsters (3,4,16,17). ...
Tobacco smoke is considered to be a major risk factor in the development of cardiac diseases and lung cancer. It has also been shown that periodontitis is more prevalent and more severe in smokers than in non-smokers. Nicotine, the major pyridine alkaloid in tobacco, has been shown to participate in periodontal disease, exerting both local and systemic effects. In the present study, the effects of nicotine (6μg/ml, 60μg/ml and 600μg/ml) on human gingival fibroblasts (HGF) were assessed by using various exposure protocols. The responses of HGF cultures obtained from smokers and non-smokers were compared to those found when using a continuous cell line (L-929). Neutral red uptake (NRU) and the measurement of DNA content with bis-benzimide dye were used to assess cell viability and cell number, respectively. NRU was the most sensitive technique for the detection of cytotoxic effects. L-929 cells were found to be affected by nicotine in the NRU assay, with a strong cytotoxic effect with 600μg/ml nicotine, and a "response" with 60μg/ml nicotine when prolonged or double challenge was applied. Non-smoker HGF and smoker HGF reacted to nicotine in different ways, depending on the concentrations and the exposure times used, but had identical reactions following double exposure. With the Hoechst DNA assay, 600μg/ml nicotine was found to affect the growth of non-smoker HGF after long or repeated exposure, while smoker HGF were affected only by repeated exposure; growth of L-929 cells was not affected. It was concluded that HGF from smokers are able to sustain higher concentrations of nicotine without adverse effects than are non-smoker HGF and L-929 cells. If this occurs in vivo, nicotine would not be considered to be a major toxicant to HGF in smokers.
1999 FRAME.
... BAL fluid from chronic smokers contains elevated levels of inflammatory cells and inhalation of cigarette smoke results in an additional, acute enhancement in the numbers of neutrophils present [179]. In addition, the numbers of neutrophils circulating in the peripheral blood increase [180] and these cells express higher levels of adhesion molecules [181] following such acute exposure. The acute effects of smoking on the levels of inflammatory mediators in chronic smokers have also been examined. ...
... After smoking one cigarette, nitrite, nitrate and cysteine levels in peripheral blood decrease [62]. In some studies, no difference has been observed in the production of reactive oxygen intermediates from peripheral blood neutrophils following smoke exposure [63], although this finding has not been universal [64]. The antioxidant capacity of blood also fell immediately after smoke exposure [61,65] and plasma lipid products increased [62,65]. ...
Chronic obstructive pulmonary disease (COPD) is a slowly progressive condition characterised by airflow limitation, which is largely irreversible [1]. The main aetiological factor in this condition is cigarette smoking and the pathogenesis of COPD is therefore strongly linked to the effects of cigarette smoke. Inhaling cigarette smoke produces an inflammatory response in the lungs of all smokers [2]. However, in those smokers who develop COPD an abnormal or enhanced inflammatory response is thought to occur, which results in the pathological changes in the lungs that characterise COPD [3]. The lungs are unique compared with other organs in that they are directly exposed to high levels of oxygen. In addition, because of its direct contact with the environment, the respiratory epithelium is a major target for oxidative injury from oxidants generated either exogenously (inhaled oxidants such as cigarette smoke or air pollutants), or endogenously from phagocytes and other cell types. As a result, the lungs need to have efficient enzymatic and nonenzymatic antioxidant systems to protect the airways against exogenous and endogenous oxidants. If the balance between oxidants and antioxidants shifts in favour of the former, owing to an excess of oxidants and/or a depletion of antioxidants, oxidative stress occurs. Since cigarette smoke contains 10 17 molecules per puff [4], it has been proposed that an imbalance occurs in some smokers, resulting in oxidative stress that has a role in many of the pathogenic mechanisms in COPD [5]. Both reactive oxygen and reactive nitrogen (ROS and RNS, respectively) species contribute to the oxidative stress that occurs in COPD. Oxygen is a key element in the process of oxidation of organic compounds by which mammalian cells produce the energy needed to sustain life. Of all of the oxygen humans breathe, 11% undergoes tetravalent reduction producing water, a reaction catalysed by a cytochrome oxidase in the mitochondrial electron transport chain. Oxygen undergoes single electron reductions (fig. 1). Tetravalent reduction of oxygen can lead to the production of ROS, both free radicals (reactive molecules with at least one unpaired electron, designated here by the . symbol) and nonradical oxidants. The addition of one electron to oxygen produces superoxide (O 2 .-), a second electron produces hydrogen peroxide (H 2 O 2) and a third electron leads to the formation of the very reactive hydroxyl radical (. OH). The addition of a fourth electron results in it being fully reduced to water [6]. These ROS can react with other molecules such as proteins, lipids and DNA. Other oxidants include the alkoxyl (RO .), peroxyl (RO 2 .) and hydroperoxyl free radicals, singlet oxygen and hypochlorous acid (HOCL). . OH is the most reactive of all the radicals and reacts immediately with organic molecules at its site of production [7]. Nitric oxide (NO .) is produced endogenously, from its amino acid substrate l-arginine, by the reaction of nitric oxide synthases (NOS; fig. 2) [9]. The inducible form of NOS Eur Respir Mon, 2006, 38, 100–129. Printed in UK -all rights reserved. Copyright ERS Journals Ltd 2006; European Respiratory Monograph; ISSN 1025-448x.
... Nicotine is a major immune suppressive component in cigarette smoke, while chronic exposure to cigarette smoke causes alterations in humoral and cellular immunity [19]. It is hypothesized that the increased disease susceptibility reflects cigarette smoke-induced changes in the immune system [20] and chronic exposure to cigarette smoke suppresses a wide range of immunological parameters in human and animal models [35]. ...
Unlabelled:
Forty adult female rats were randomly divided into four groups: control, nicotine, nicotine+vitamin C and nicotine+selenium group. Splenic tissues concentrations of thiobarbituric acid reactive substances (TBARS), nitric oxide, superoxide dismutase (SOD) and catalase (CAT) activities were measured. The P53 and Bcl2 proteins were detected by Western blot and their expression in splenic tissues were measured by quantitative real time PCR in all groups. Compared to control group, nicotine increased the concentrations of TBARS and nitric oxide significantly. However, Vit. C or Se supplementation with nicotine caused a significant decrease in these concentrations. SOD and CAT activities of nicotine group decreased significantly compared to control group. Treatment with Vit. C or Se plays a significant role in elevation of SOD and CAT activities. In splenic tissues, nicotine significantly decreases the protein levels and the mRNA expression of P53 and increases the protein levels of Bcl2 and its expression. Administration of Vit. C. to nicotine-treated rats completely reversed the decrease in P53 levels and its mRNA expression and the increase in Bcl2 levels and its mRNA expression to the control values. In contrast, Se administration did not induce any significant changes in these genes levels or expressions compared to nicotine group.
Conclusion:
Vit. C supplementation to nicotine treated rats was more effective than selenium in attenuation of nicotine-induced oxidative stress, p53 and Bcl2 expression in rat spleen tissues.
... 199 In other studies, however, smokers' PBMCs exhibited enhanced production of IL-1, IL-6, and TNF-α in response to mitogens, 193 while serum levels of IL-1, IL-6, and PGE 2 were unchanged. 200 Perhaps, the most convincing examples of smokingmediated immunosuppression have been demonstrated in the case of alveolar macrophages and epithelial cells that comprise the airway respiratory tract. LPS-induced production of pro-inflammatory cytokines has been shown to be severely impaired in alveolar macrophages obtained from smokers compared to macrophages from non-smoking volunteers. ...
Many host cell types, including endothelial and epithelial cells, neutrophils, monocytes, natural killer cells, dendritic cells and macrophages, initiate the first line of defense against infection by sensing conserved microbial structures through Toll-like receptors (TLRs). Recognition of microbial ligands by TLRs induces their oligomerization and triggers intracellular signaling pathways, leading to production of pro- and anti-inflammatory cytokines. Dysregulation of the fine molecular mechanisms that tightly control TLR signaling may lead to hyperactivation of host cells by microbial products and septic shock. A prior exposure to bacterial products such as lipopolysaccharide (LPS) may result in a transient state of refractoriness to subsequent challenge that has been referred to as `tolerance'. Tolerance has been postulated as a protective mechanism limiting excessive inflammation and preventing septic shock. However, tolerance may compromise the host's ability to counteract subsequent bacterial challenge since many septic patients exhibit an increased incidence of recurrent bacterial infection and suppressed monocyte responsiveness to LPS, closely resembling the tolerant phenotype. Thus, by studying mechanisms of microbial tolerance, we may gain insights into how normal regulatory mechanisms are dysregulated, leading ultimately to microbial hyporesponsivess and life-threatening disease. In this review, we present current theories of the molecular mechanisms that underlie induction and maintenance of `microbial tolerance', and discuss the possible relevance of tolerance to several infectious and non-infectious diseases.
... Overall, no difference in the investigated lymphocyte subpopulations was seen between SM and NSM. These findings are similar to a study investigating acute effects of smoking and environmental tobacco smoke in five smokers and non-smokers [33], showing increased NK cells and decreased CD3+ and CD19+ cells which did not reach statistical significance. However, our results may be limited by the markers used to define the different lymphocyte subpopulations. ...
Background
Significant immunomodulatory effects have been described as result of cigarette smoking in adults and pregnant women. However, the effect of cigarette smoking during pregnancy on the lymphocyte subpopulations in newborns has been discussed, controversially.
Methods
In a prospective birth cohort, we analyzed the peripheral lymphocyte subpopulations of smoking (SM) and non-smoking mothers (NSM) and their newborns and the replicative history of neonatal, mostly naive CD4 + CD45RA + T cells by measurements of T-cell-receptor-excision-circles (TRECs), relative telomere lengths (RTL) and the serum cytokine concentrations.
Results
SM had higher lymphocyte counts than NSM. Comparing SM and NSM and SM newborns with NSM newborns, no significant differences in proportions of lymphocyte subpopulations were seen. Regardless of their smoking habits, mothers had significantly lower naive T cells and higher memory and effector T cells than newborns. NSM had significantly lower percentages of CD4 + CD25++ T cells compared to their newborns, which was not significant in SM. There were no differences regarding cytokine concentrations in newborns of SM and NSM. However, NSM had significantly higher Interleukin-7 concentrations than their newborns. Regardless of smoking habits of mothers, newborns had significantly longer telomeres and higher TRECs than their mothers. Newborns of SM had significantly longer telomeres than newborns of NSM.
Conclusions
Apart from higher lymphocyte counts in SM, our results did not reveal differences between lymphocyte subpopulations of SM and NSM and their newborns, respectively. Our finding of significantly longer RTL in newborns of SM may reflect potential harm on lymphocytes, such as cytogenetic damage induced by smoking.
... Cigarette smoke alters antigen-mediated T-cell signaling [241], reduces clonal expansion and activation of CD4 T cells and reduces activation of CD8 T cells in response to infection [242]. Exposure to cigarette smoke also reduces the production of pro-inflammatory cytokines by antigen-presenting cells [243,244], decreases numbers of peripheral B cells and NK cells, and reduces serum immunoglobulin levels [234,[245][246][247], other possible mechanisms underlying susceptibility to viral respiratory infection. ...
Multiple sclerosis (MS) is a chronic disabling disease of the central nervous system commonly affecting young adults. Pathologically, there are patches of inflammation (plaques) with demyelination of axons and oligodendrocyte loss. There is a global latitude gradient in MS prevalence, and incidence of MS is increasing (particularly in females). These changes suggest a major role for environmental factors in causation of disease. We have reviewed the evidence and potential mechanisms of action for three exposures: vitamin D, Epstein Barr virus and cigarette smoking. Recent advances supporting gene-environment interactions are reviewed. Further research is needed to establish mechanisms of causality in humans and to explore preventative strategies.
... The acute effects of cigarette smoking have been extensively studied (van der Vaart et al., 2004). In human studies, acute exposure to cigarette smoke induces elevation in peripheral blood neutrophils and granulocytes (Abboud et al., 1986;Hockertz et al., 1994). In the lungs of cigarette smokers, acute cigarette smoking has been shown to increase lung endothelial permeability (Ward et al., 2000) and oxidative stress biomarkers such as 8-iso-prostane, hydrogen peroxide and superoxide (Morrison et al., 1999;Guatura et al., 2000;Montuschi et al., 2000). ...
Tobacco smoking represents a global public health threat, claiming approximately 5 million lives a year. Waterpipe tobacco use has become popular particularly among youth in the past decade, buttressed by the perception that the waterpipe "filters" the smoke, rendering it less harmful than cigarette smoke.
In this study, we examined the acute exposure of waterpipe smoking on lung inflammation and oxidative stress in mice, and compared that to cigarette smoking.
Mice were divided into three groups; fresh air control, cigarette and waterpipe. Animals were exposed to fresh air, cigarette, or waterpipe smoke using whole body exposure system one hour daily for 7 days.
Both cigarette and waterpipe smoke exposure resulted in elevation of total white blood cell count, as well as absolute count of neutrophils, macrophages, and lymphocytes (P < 0.01). Both exposures also elevated proinflammatory markers such as TNF-α and IL-6 in BALF (P < 0.05), and oxidative stress markers including GPx activity in lungs (P < 0.05). Moreover, waterpipe smoke increased catalase activity in the lung (P < 0.05). However, none of the treatments altered IL-10 levels.
Results of cigarette smoking confirmed previous finding. Waterpipe results indicate that, similar to cigarettes, exposure to waterpipe tobacco smoke is harmful to the lungs.
... In contrast, active tobacco cigarette smoking in smokers and passive tobacco cigarette smoking in never smokers increase white blood cell count, lymphocyte count, and granulocyte count for at least one hour. The results on active tobacco cigarette smoking are in line with published evidence showing an increased number of leukocytes and granulo-cytes following acute smoking (Hockertz et al., 1994;Morrison et al., 1999;Winkel and Statland, 1981). With respect to passive tobacco cigarette smoking, some (Panagiotakos et al., 2004;Ronchetti et al., 1990), but not all (Husgafvel-Pursiainen et al., 1987;Sochaczewska et al., 2010;Venn and Britton, 2007), studies suggest that chronic exposure to passive tobacco cigarette smoking leads to increased white blood cell count. ...
... Several potential mechanisms may explain the links between in utero exposure and subsequent changes in cord blood cells. Several experimental studies have supported the hypothesis that antigenic cell stimulation by air pollutants and their metabolic by-products could be at the origin of the rise in some lymphocyte subsets by highlighting the disturbance of lymphocyte immunophenotype distributions by xenobiotics including tobacco smoke[59]and chemicals[60]. However, air pollutants could also act as adjuvants by amplifying specific responses towards other antigens such as viruses or allergens. ...
Toxicants can cross the placenta and expose the developing fetus to chemical contamination leading to possible adverse health effects, by potentially inducing alterations in immune competence. Our aim was to investigate the impacts of maternal exposure to air pollution before and during pregnancy on newborn's immune system.
Exposure to background particulate matter less than 10 μm in diameter (PM10) and nitrogen dioxide (NO2) was assessed in 370 women three months before and during pregnancy using monitoring stations. Personal exposure to four volatile organic compounds (VOCs) was measured in a subsample of 56 non-smoking women with a diffusive air sampler during the second trimester of pregnancy. Cord blood was analyzed at birth by multi-parameter flow cytometry to determine lymphocyte subsets.
Among other immunophenotypic changes in cord blood, decreases in the CD4+CD25+ T-cell percentage of 0.82% (p = 0.01), 0.71% (p = 0.04), 0.88% (p = 0.02), and 0.59% (p = 0.04) for a 10 μg/m3 increase in PM10 levels three months before and during the first, second and third trimester of pregnancy, respectively, were observed after adjusting for confounders. A similar decrease in CD4+CD25+ T-cell percentage was observed in association with personal exposure to benzene. A similar trend was observed between NO2 exposure and CD4+CD25+ T-cell percentage; however the association was stronger between NO2 exposure and an increased percentage of CD8+ T-cells.
These data suggest that maternal exposure to air pollution before and during pregnancy may alter the immune competence in offspring thus increasing the child's risk of developing health conditions later in life, including asthma and allergies.
... Degradation of IL-6, along with a decrease in its activity, was observed in the BALF and alveolar macrophages derived from rats acutely exposed to tobacco smoke (Pessina et al., 1996;Dubar et al., 1993). By contrast, IL-6 levels in human blood were unaffected by exposure to tobacco smoke (Hockertz et al., 1994), suggesting that the acute effects of tobacco smoke on IL-6 are local, or that other cells in the blood may regulate the IL-6 levels. ...
... Theoretically, as indicated above, we expected a larger RR for mortality than for morbidity based on the biology of disease, and this hypothesis was confirmed. The same reasoning would apply for other chronic and infectious disease end-points of alcohol, as well as to other substancerelated risk factors that have effects on the immune system, such as tobacco or illegal drugs [61,62]. The current practice in epidemiology tends to derive RR from both end-points combined without testing for potential differences. ...
Alcohol is an established risk factor for liver cirrhosis. It remains unclear, however, whether this relationship follows a continuous dose-response pattern or has a threshold. Also, the influences of sex and end-point (i.e. mortality vs. morbidity) on the association are not known. To address these questions and to provide a quantitative assessment of the association between alcohol intake and risk of liver cirrhosis, we conducted a systematic review and meta-analysis of cohort and case-control studies.
Studies were identified by a literature search of Ovid MEDLINE, EMBASE, Web of Science, CINAHL, PsychINFO, ETOH and Google Scholar from January 1980 to January 2008 and by searching the references of retrieved articles. Studies were included if quantifiable information on risk and related confidence intervals with respect to at least three different levels of average alcohol intake were reported. Both categorical and continuous meta-analytic techniques were used to model the dose-response relationship.
Seventeen studies met the inclusion criteria. We found some indications for threshold effects. Alcohol consumption had a significantly larger impact on mortality of liver cirrhosis compared with morbidity. Also, the same amount of average consumption was related to a higher risk of liver cirrhosis in women than in men.
Overall, end-point was an important source of heterogeneity among study results. This result has important implications not only for studies in which the burden of disease attributable to alcohol consumption is estimated, but also for prevention.
... Smoking has paradoxical effects on the immune system. While studies show that smoking is associated with immune activation, such as an enhanced phytohemagglutinin response (3,4), alveolar macrophage activation (5), and increased soluble interleukin-2 receptor levels (6), other studies report local immune suppression, such as a decreased interleukin-1 release from alveolar macrophages (7,8) and a decreased CD4/CD8 ratio (9)(10)(11). A higher incidence of non-Hodgkin's lymphoma and Kaposi's sarcoma is associated with subclinical immune suppression (12,13). ...
... In BALF and alveolar macrophages derived from rats exposed acutely to tobacco smoke, degradation of IL- 6 and decrease in its activity was observed [63,64] . In contrast , IL-6 levels in human blood were unaffected by tobacco smoke exposure [65] suggesting that the acute effects of MTS on IL-6 is local or that other cells in blood may mediate the IL-6 levels. Induction of IL-6 at 12 weeks in our model suggests that continued exposure of these mice to MTS may induce other pathways that initiate inflammatory processes. ...
Tobacco smoking is associated with lung cancer and other respiratory diseases. However, little is known about the global molecular changes that precede the appearance of clinically detectable symptoms. In this study, the effects of mainstream tobacco smoke (MTS) on global transcription in the mouse lung were investigated.
Male C57B1/CBA mice were exposed to MTS from two cigarettes daily, 5 days/week for 6 or 12 weeks. Mice were sacrificed immediately, or 6 weeks following the last cigarette. High density DNA microarrays were used to characterize global gene expression changes in whole lung. Microarray results were validated by Quantitative real-time RT-PCR. Further analysis of protein synthesis and function was carried out for a select set of genes by ELISA and Western blotting.
Globally, seventy nine genes were significantly differentially expressed following the exposure to MTS. These genes were associated with a number of biological processes including xenobiotic metabolism, redox balance, oxidative stress and inflammation. There was no differential gene expression in mice exposed to smoke and sampled 6 weeks following the last cigarette. Moreover, cluster analysis demonstrated that these samples clustered alongside their respective controls. We observed simultaneous up-regulation of interleukin 6 (IL-6) and its antagonist, suppressor of cytokine signalling (SOCS3) mRNA following 12 weeks of MTS exposure. Analysis by ELISA and Western blotting revealed a concomitant increase in total IL-6 antigen levels and its downstream targets, including phosphorylated signal transducer and activator of transcription 3 (Stat3), basal cell-lymphoma extra large (BCL-XL) and myeloid cell leukemia 1 (MCL-1) protein, in total lung tissue extracts. However, in contrast to gene expression, a subtle decrease in total SOCS3 protein was observed after 12 weeks of MTS exposure.
Global transcriptional analysis identified a set of genes responding to MTS exposure in mouse lung. These genes returned to basal levels following smoking cessation, providing evidence to support the benefits of smoking cessation. Detailed analyses were undertaken for IL-6 and its associated pathways. Our results provide further insight into the role of these pathways in lung injury and inflammation induced by MTS.
... This has been con®rmed by animal studies. Leucocytes from smoke-exposed animals exhibit attenuated proliferative responses to both B-cell mitogens and antigens (50). ...
Sixty-five patients with generalised early-onset periodontitis (G-EOP) (age range 16-42 years, 32 smokers and 33 non-smokers) were assessed for antibody titres and avidity to a panel of five suspected periodontal pathogens (Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Treponema denticola and Bacteroides forsythus). Thirty-four of these patients were untreated (17 smokers and 17 non-smokers), and thirty-one were in the maintenance phase of periodontal therapy (15 smokers and 16 non-smokers). Previous studies have investigated the effect of smoking on IgG levels in periodontitis patients in the context of the more extensive periodontal destruction seen in smokers. Based on this literature our hypothesis was that smokers would have depressed serum IgG levels directed against recognised periodontal pathogens compared with non-smokers. Antibody titres were measured by ELISA deploying fixed whole cells as coating. The IgG response was detected with biotin-anti-human IgG and avidin-peroxidase; avidity was determined by elution with ammonium thiocyanate. Median titres to A. actinomycetemcomitans, P. intermedia and T. denticola were significantly lower in maintenance patient smokers (p= 0.02, 0.02 and 0.002 respectively) but not in untreated patients. Avidity to P. gingivalis was also lower in smoking maintenance patients (p = 0.003) but not in untreated patients. These findings may imply some interruption of immune maturation in smokers following periodontal treatment.
Cigarette smoke is known to be associated with the incidence of a variety of pulmonary diseases, and alveolar macrophages are a key player in the defense mechanism against inhalable toxicants. Herein, we have found that a hydrophilic fraction in smoke extracts from 3R4F reference cigarettes (CSE) contains high concentrations of volatile substances compared to cigarette smoke condensate (amphoteric fraction). We also identified the toxic mechanism of CSE using MH‐S, a mouse alveolar macrophage cell line. CSE decreased cell viability accompanying increased lactate dehydrogenase release. Additionally, mitochondrial volume and the potential increased along with enhanced expression of mitochondrial fusion proteins and decreased adenosine triphosphate production. Similarly, CSE clearly induced increase of catalase activity and intracellular calcium concentration and decrease of endoplasmic reticulum and lysosome volume at the highest dose. More interestingly, damaged organelles accumulated in the cytosol, and CSE‐containing particles specifically penetrated to mitochondria. Meanwhile, any significant change in autophagy related protein expression was not found in CSE‐treated cells. Subsequently, we evaluated the effects of CSE on secretion of inflammatory related cytokines and chemokines, considering the relationship between organelle damage and the disturbed immune response. Very importantly, we found that expression of innate and adaptive immunity related mediators is disrupted following CSE exposure. Taken together, we suggest that CSE may cause the accumulation of damaged organelles in the cytoplasm by impairing selective autophagic function. In addition, this accumulation is responsible for the inadequate ability of immune cells to repair the damage of lung tissue following exposure to CSE.
Abstract Rats exposed to tobacco cigarette smoke (CS) via inhalation from a high-tar cigarette for 4 h/day over a 14-day period showed measurable changes in specific biochemical and immunological markers of lung injury when compared to control rats exposed to clean dry air. We found epithelial cell layer thickening and increased lung permeability as measured by histopathological examination, and increased levels in hexose and protein exudation present in bronchoalveolar lavage fluid. Exposure to CS also caused a significant reduction in immunoglobulin A (lgA) levels (p < .001), which persisted after postexposure recovery. In addition, alveolar macrophages from rats exposed to CS were unresponsive to lipopolysaccharide stimulation in vitro as shown by reduced expression of cytokine interleukin 1β mRNA compared to air controls. These results suggest that high-tar cigarette smoke can induce disfunctional changes in immune systems. However, as no reproducible smoke-induced changes were seen using medium-tar cigarettes, we have to conclude that the rat may not be the most sensitive species in which to evaluate the mode of action of cigarette smoke on the lung.
Nicotine, a small organic alkaloid synthesized by tobacco plants, is the addictive component of cigarettes. (1) Its basic properties permit easy transport across the small intestine and lung tissues into the blood. Nicotine’s size and lipophilic characteristics allow for a small amount to cross cell membranes directly, without interception by a receptor, (1) although its primary effects are via receptor mediation. This small alkaloid acts as an agonist at the nicotinic acetylcholine receptors (nAChRs), found mainly in the central (CNS) and peripheral nervous system, as well as on many other tissue cells throughout the body. (2) The distribution of these receptors on a large variety of cells helps to explain why nicotine has been associated with a wide range of biological actions. These actions of nicotine account, in part, for alterations in the cardiovascular, pulmonary, gastrointestinal, urogenital, hepatic, and nervous systems caused by smoking tobacco. (3–7) The most frequent way to acquire nicotine is via tobacco products. Cigarettes contain approximately 1.5–2.5 mg nicotine per cigarette, with the highest level of nicotine reported in the plasma of heavy smokers being about 700 ng/ml. (8,9) Interestingly, different areas of the body accumulate nicotine at different rates. For example, nicotine is retained at a higher level in the cervix, (10) kidneys, gastrointestinal tract, heart, and muscles (11) than in blood. In terms of distribution in the blood, smoking one cigarette results in about 50 ng nicotine/ml in arterial blood contrasted with the 20 ng nicotine/ml in venous blood. (12) This type of differential distribution of nicotine is important to keep in mind when comparing results of nicotinic action from different experimental protocols.
The leukocyte count and concentrations of(s)ICAM-1 and(s)VCAM-1 in smokers were investigated. The subjects were 96 persons (31 smokers and 65 nonsmokers) hospitalized for a complete health checkup examination. There were no differences between the two groups for background factors (age (nonsmokers, 56.2 ± 9.2 vs smokers, 52.6 ± 11.3)gender ratio (m/f)(nonsmokers, 47/18 vs smokers, 24/7) and drinker ratio (+/-) (nonsmokers, 45/20 vs smokers, 26/5)). For smokers, the average number of cigarettes smoked daily, smoking period(ys) and Brinkman Index were 21.4 ± 10.4, 26.2± 14.5 and 584.2 ± 476.9, respectively. In smokers, total leukocyte count (l μ 1) (6371.0 ± 1303.4 vs 5063.1 ± 1279.1,(p)<0.0001), and(s)ICAM-1 concentration (ng/ml) (202.6 ± 64.0 vs 163.0 ± 60.8,(p)<0.01) were higher than those in nonsmokers. No significant difference in the(s)VCAM-1 concentration was shown between the two groups. Items showing large correlation coefficients with the number of cigarettes smoked daily were the total leukocyte count (r = 0.45,(p)<0.0001) and(s)ICAM-1 (r = 0.36,(p)<0.0001). In smokers,(s)ICAM-1 showed correlation with the total leukocyte count (r = 0.42,(p)<0.05) . We conclude diat the leukocyte count and(s)ICAM-1 concentration in healthy smokers are higher than those in nonsmokers.
Vardavas CI, Plada M, Tzatzarakis M, Marcos A, Warnberg J, Gomez‐Martinez S, Breidenassel C, Gonzalez‐Gross M, Tsatsakis AM, Saris WH., Moreno LA, Kafatos AG. Passive smoking alters circulating naïve/memory lymphocyte T‐cell subpopulations in children.
Pediatr Allergy Immunol 2010: 21: 1171–1178.
© 2010 John Wiley & Sons A/S
While it has been indicated that exposure to second‐hand smoke (SHS) can cause a local in vivo response, limited evidence exists on its possible systemic effects from population‐based levels of exposure. We investigated into a possible systemic response in the immune parameters and lymphocyte subsets, i.e. B cell (CD19+), T cell (CD4+CD45RO+, CD4+CD45RA+, CD3+CD45RO+, CD3+CD45RA+) and natural killer (CD3+CD16CD56+) lymphocyte subsets relative to exposure to SHS. Blood was drawn from healthy, verified non‐smoker, adolescent subjects (n = 68, mean age 14.2) and analysed for cotinine, antioxidants and lymphocyte immunophenotyping. SHS exposure was assessed using serum cotinine. Biomarker quantified exposure to SHS was correlated with a linear dose–response reduction in the percentages of memory CD4+CD45RO+ (p = 0.005) and CD3+CD45RO+ T‐cell subsets (p = 0.005 and p = 0.003, respectively) and a linear increase in the percentage of naïve CD4+CD45RA+ and CD3+CD45RA+ T‐cell subsets (p = 0.006 and p = 0.003, respectively). Additionally, higher exposure to SHS was associated with a higher CD4+CD45RA+ count (532 vs. 409 cells/ml, p = 0.017). Moreover, after controlling for age, gender, body mass index and plasma antioxidants, SHS exposure was found to be associated with the percentage of circulating naïve and memory CD4+ and CD3+ T‐cell subpopulations, as revealed through a linear regression analysis. These findings indicate a systemic immunological response in healthy adolescents exposed to population‐based levels of SHS exposure and imply an additional biological pathway for the interaction between exposure to SHS and its adverse effects on human health.
Globally, tobacco use is associated with 5 million deaths per annum and is regarded as one of the leading causes of premature death. Major chronic disorders associated with smoking include cardiovascular diseases, several types of cancer, and chronic obstructive pulmonary disease (lung problems). Cigarette smoking (CS) generates a cumulative oxidative stress, which may contribute to the pathogenesis of chronic diseases. Mainstream and side stream gas-phase smoke each have about the same concentration of reactive free radical species, about 1 × 10(16) radicals per cigarette (or 5 × 10(14) per puff). This effect is critical in understanding the biologic effects of smoke. Several lines of evidence suggest that cigarette smoke constituents can directly activate vascular reactive oxygen species production. In this work we present multiple evidence that CS provide the important risk factors in many age-related diseases, and is associated with increased cumulative and systemic oxidative stress and inflammation. The cited processes are marked by increased white blood cell (leucocytes, WBCs) turnover. The data suggest an alteration of the circulating WBCs by CS, resulting in increased adherence to endothelial cells. Telomeres are complex DNA-protein structures located at the end of eukaryotic chromosomes. Telomere length shortens with biologic age in all replicating somatic cells. It has been shown that tobacco smoking enhances telomere shortening in circulating human WBCs. Telomere attrition (expressed in WBCs) can serve as a biomarker of the cumulative oxidative stress and inflammation induced by smoking and, consequently, show the pace of biologic aging. We originally propose that patented specific oral formulations of nonhydrolized carnosine and carcinine provide a powerful tool for targeted therapeutic inhibition of cumulative oxidative stress and inflammation and protection of telomere attrition associated with smoking. The longitudinal studies of the clinical population groups described in this study including elderly support the hypothesis that telomere length is a predictor of survival and therapeutic treatment requirement associated with smoking behavior.
Thesis (Ph. D.)--University of Washington, 2008. Air pollution is associated with adverse health outcomes, and changes in the immune system may be intermediate steps between exposure and a clinically relevant adverse health outcome. We analyzed the associations between three different types of measures of air pollution exposure and five biomarkers of immune function among 115 overweight and obese postmenopausal women whose immunity was assessed as part of a year-long moderate exercise intervention trial. For air pollution metrics, we assessed: (1) residential proximity to major roads (freeways, major arterials and truck routes), (2) fine particulate matter(PM2.5) at the nearest monitor to the residence averaged over three time windows (3-days, 30-days and 60-days), and (3) nitrogen dioxide (NO2) modeled based on land use characteristics. Our immune biomarkers included three measures of inflammation---C-reactive protein, serum amyloid A and interleukin-6---and two measures of cellular immunity---natural killer cell cytotoxicity and T lymphocyte proliferation.We hypothesized that living near a major road, increased exposure to PM2.5 and increased exposure to NO2 would each be independently associated with increased inflammation and decreased immune function. We observed a 21% lower average natural killer cell cytotoxicity among women living within 150 meters of a major arterial road compared to other women. For PM2.5 , we observed changes in 3 of 4 indicators of lymphocyte proliferation stimulated by anti-CD3---an antibody to the T cell receptor associated with increases in 3-day averaged PM2.5. For 30-day averaged PM 2.5 and 60-day averaged PM2.5 we did not observe any statistically significant associations. We observed an increase in lymphocyte proliferation index stimulated by the plant protein phytohemagglutinin (PHA) at 1 of 2 PHA concentrations in association with modeled NO2. For the three inflammatory markers, we observed no notable associations with any of our measures of air pollution.If confirmed, our results provide preliminary evidence to support the biologic plausibility of previously observed associations between traffic and colds and infections, suggest immune function should be considered as part of the assessment of regulatory standards for PM2.5 and indicate that living in close proximity to major roads may have adverse health impacts.
The general objective of the studies in this thesis is to elucidate the role apoptotic cells play in the etiopathogenesis of SLE. First, we focus on the function of soluble Fas (sFas), a molecule which has been described to interfere with the induction of Fas-mediated apoptosis. It has been suggested that elevated levels of sFas hamper apoptosis (autoreactive) lymphocytes, subsequently resulting in autoimmunity.
This study examined relationships between psychologic characteristics and enumerative immune responses to an acute laboratory stressor. Lymphocyte subsets were measured in 104 subjects at rest and following a 6-minute laboratory naturalistic speaking stressor. Multiple linear regression was utilized to assess relationships between immune reactivity (change scores) and anger expression, hostility, anxiety, depression, and stress. The task resulted in significant increases over baseline in WBC (p < 0.001), T-suppressor/cytotoxic CD8 cells (p = 0.010) natural killer CD56 cells (p < 0.0001), and CD57 (p < 0.0001) cells, and significant decreases in T-cells (p = 0.012), T-helper cells (p = 0.003), B-cells (p < 0.001), and the T-helper/suppressor ratio (p < 0.001). In general, the regression suggested that moderate associations exist between certain psychologic attributes and acute subset redistribution. For example, the increase in natural killer cell subsets was significantly negatively associated with anger expression, hostility, and depression. Suppressor/cytotoxic (CD8) cell reactivity was associated with baseline as well as with the task-induced changes in anxiety. B-cell (CD19) responses were related to the subject's age, expression of anger, and depression scores. As with the cardiovascular reactivity literature, these findings suggest that a relationship exists between certain psychologic characteristics such as anger and anxiety and immune reactivity to acute stress.
Kidney International aims to inform the renal researcher and practicing nephrologists on all aspects of renal research. Clinical and basic renal research, commentaries, The Renal Consult, Nephrology sans Frontieres, minireviews, reviews, Nephrology Images, Journal Club. Published weekly online and twice a month in print.
Although considerable work has been done on the potential health effects of smoking, little is known about the contribution of nicotine to those effects. This paper presents an overview of the immune system, and a discussion of the existing literature on the effects of tobacco smoke and nicotine on immunity. Treatment with nicotine has been shown to influence all aspects of the immune system, including alterations in humoral and cellular immunity. In addition, preliminary data suggest that gender and genetic factors impact on the immunological effects of nicotine. Finally, the possible mechanisms that might mediate the effects of nicotine are discussed.
The health, economic and social costs of smoking are enormous and well known to physicians. Smoking results in a lot of morbidity and mortality mainly related to cardiovascular disease, cancer and pulmonary disease. The effect of smoking on the kidneys is little appreciated. It is the purpose of this review article to give evidence from available literature that smoking is indeed deleterious to the kidneys and may result in progression of chronic renal failure to end stage renal disease. It is concluded that nephrologists, and indeed all physicians, should make a concerted effort to save their patients from this vice.
To assess lymphocyte subsets and expression of activation antigens in peripheral blood lymphocytes (PBLs) in chronic alcoholism, a cross-sectional study with 30 well-nourished chronic alcoholics and 30 controls was performed. Studies included detailed clinical and laboratory evaluation, nutritional status assessment, and determination of lymphocyte subpopulations, as well as activation antigens. A significant decrease of B cells (CD19+) was observed in chronic alcoholics, compared with controls (p < 0.001). A significant increase of PBLs expressing CD69 and CD25 (p < 0.01, both) in chronic alcoholics was also detected, whereas CD71 expression was unaffected. In addition, T lymphocytes expressing HLA-DR were significantly higher in chronic alcoholics than controls (p < 0.05). The serum level of soluble interleukin-2 receptor was also significantly higher in the alcoholic group, compared with controls (p = 0.04). Moreover, the estimated total lifetime dose of ethanol consumed correlated positively with the percentage of PBLs expressing CD25 (r = 0.48; p = 0.01) and negatively with PBLs expressing CD71 (r = -0.39; p = 0.04). By contrast, the changes were not related to age, nutritional status, or the presence of other ethanol-related diseases. In conclusion, chronic alcoholics present a significant decrease of B cells and an "incomplete activation state" of PBLs that depends on the dose of ethanol consumed.
Systemic lupus erythematosus (SLE) is characterized by generalized immune activation. Part of this might be explained by a decreased rate of apoptosis, possibly related to elevated levels of soluble Fas (sFas) which can inhibit Fas mediated apoptosis of lymphocytes. In order to substantiate the relation between levels of sFas and lymphocyte activation in SLE we monitored sFas levels, lymphocyte activation and disease activity in 25 SLE patients. SLEDAI scores were registered and sera were assayed for sFas levels by an enzyme-linked immunosorbent assay. Flow cytometry was used to monitor the state of activation of lymphocyte subsets. Eighteen healthy, age-matched volunteers served as controls. Soluble Fas levels were elevated in SLE patients (n=25) compared to healthy controls (n=18, P=0.002). Soluble Fas levels correlated with SLEDAI scores (r=0.45, P=0.02). Levels of sFas correlated with the percentages of activated B cells defined as CD20(+)CD38(+) cells (r=0.47, P=0.009). Percentages of CD20(+)CD38(+) cells were increased in quiescent SLE compared to healthy controls (P=0.003). The expression of activation markers on CD4(+) T lymphocytes (IL-2R, P=0.04; HLA-DR, P=0.01) and CD8(+) T lymphocytes (HLA-DR, P=0.007) was also increased in quiescent SLE compared to controls. Activation markers on all lymphocyte subsets tended to increase further during disease activity. No correlation was observed between percentages of activated T lymphocyte subsets and levels of sFas. In conclusion, soluble Fas levels are increased in SLE patients and correlate with disease activity as measured by the SLEDAI score and B and T cell subsets are activated even during quiescent SLE. Serum levels of sFas correlate with percentages of activated B cells but not with that of activated T cells.
The aim of this cross-sectional study was to determine concentrations of prostaglandin E2 (PGE2) in gingival crevicular fluid (GCF) in a cohort of periodontal disease-resistant (PDR) adults with chronic gingivitis but with minimal evidence of bone loss, and to compare these data with GCF-PGE2 levels in patients with untreated chronic adult periodontal disease (CAPD). 20 PDR and 35 CAPD subjects with mean (+/-se) ages 52.4 (+/-2.9) and 43.7 (+/-1.2) years respectively, were recruited. GCF was sampled from 6 sites in each PDR subject and 4 sites in each CAPD subject. The GCF-PGE2 concentrations were determined by enzyme immunoassay (Assay Designs). Whole mouth medians of site-specific GCF-PGE2 concentrations were calculated for each subject. The means of the median GCF-PGE2 concentrations were: PDR 54.94+/-4.06 ng/ml; CAPD 41.57+/-2.91 ng/ml (p=0.009). We hypothesise that the higher concentrations of PGE2 in the PDR group may be associated with the proliferating pocket epithelia of the chronic gingivitis. In the CAPD cohort, there were no differences in GCF-PGE2 concentrations between subgroups of smokers (n=13), ex-smokers (n=11) and non smokers (n=11). In the PDR cohort, 19/20 subjects were non-smokers.
Prenatal nicotine exposure has been shown to disrupt the development of a number of peripheral organs. In the current study, we examined the effects of gestational nicotine exposure, alone or in combination with ethanol exposure, on offspring immune function. Timed pregnant rats were treated with either nicotine (6 mg/kg/day) from gestation day 4-20 using subcutaneously implanted osmotic mini-pumps or ethanol administered in the drinking water (15% w/v) from gestation day 10-20. The combined exposure group received both treatments. The ability of offspring T and B cells to proliferate in response to nonspecific stimulation by Concanavalin A or lipopolysaccharide, respectively, was determined on postnatal days 9, 15, 22, 29, 64, and 86. Offspring splenocyte beta(2)-adrenoceptor binding was also measured. Nicotine or nicotine+ethanol suppressed splenocyte responsiveness to Concanavalin A or lipopolysaccharide which was similar in timing and magnitude to that seen with ethanol alone. Splenocytes from these groups remained subresponsive to stimulation well into adulthood. The combined drug treatment caused an overall reduction in spleen beta-adrenergic receptor binding whereas the individual drug treatments did not alter the development of spleen beta-adrenergic receptors.Our results indicate that prenatal nicotine exposure can cause long-term suppression of the proliferative response of offspring immune cells. Moreover, the effects of nicotine+ethanol may cause more severe deficits in adulthood.
The immunoregulatory effects of nicotine have not been fully clarified and the reported data are often conflicting. The present study investigated the role of nicotine as an immunomodulator of murine splenocytes stimulated by lipopolysaccharide (LPS), the endotoxin component of gram-negative bacteria. BALB/c female mice of two different ages, young (2-3 months) and old (18-22 months), were used. The cells were incubated with nicotine at two different time points, 3 h pre-incubation and concurrent incubation relevant to LPS stimulation, before further incubation for 48 or 72 h. Treatment of murine splenocytes with nicotine showed an impact on cellular proliferation as well as on the production of the pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). The results indicated that nicotine significantly inhibited cellular proliferation of murine splenocytes in a concentration-related manner (32, 64 and 128 microg/ml). Timing of nicotine exposure prior to LPS stimulation was critical in terms of immunological impact on cytokine production. TNF-alpha and IL-6 production were significantly enhanced by 1 microg/ml of nicotine when cells were pre-incubated with nicotine for 3 h compared to concurrent incubation relative to LPS stimulation. The alteration in cytokine production varied with the age of the mouse. TNF-alpha production was significantly inhibited by nicotine in young mice, while IL-6 production was significantly inhibited by nicotine in old mice. Since any immunomodulation that alters the profile of these cytokines may cause an imbalance in the immune system impinging on health status, these findings may be important when dealing with the concept of nicotine as a therapeutic agent.
Apoptosis provides a mechanism for clearance of unwanted cells in a variety of situations in which programmed or physiological cell death occurs; but the premature death of defensive cells could promote infection, inflammation and concomitant disease. We detected high values of apoptosis in polymorphonuclear cells (PMN) elicited from crevicular sulci of smokers affected by adult periodontitis. To learn more about the effects of nicotine on the periodontal environment, we studied its ability to modulate the apoptosis of two phagocytic lines, PMN and mononuclear cells, which are continuously recruited from gingival vessels to prevent or control plaque extension. Brief exposure of PMN to nicotine concentrations ranging from 0.01 to 0.3% shortened, in a dose-dependent relationship, the lag culture time required to observe at fluorescent microscopy the morphological traces of apoptosis. These observations were confirmed by specific tools of apoptosis: DNA fragmentation on gel electrophoresis and expression of the apoptosis-signaling receptor Fas/Apo-1. The apoptotic effect excited by nicotine on these first line defensive cells may be an important feature of the pathogenesis of periodontal disease. As for mononuclear leukocytes, nicotine was unable to induce apoptotic modifications on cells observed up to 72 h culture time, but the drug inhibited IL-1beta release and procoagulant activity (PCA) expression. The conflicting role played by these lipopolysaccharide (LPS)-induced monocyte functions in the inflammatory process is a further intrigue in the mechanism by which nicotine compromises the oral health.
Smoking influences numbers and function of peripheral blood lymphocytes (PBL) by a process that is badly understood. We conducted this study to evaluate whether the immune impairment of smoking might be related to changes in the expression or functionality of Fas, a cell surface molecule that plays a central role in immune homeostasis and cytotoxic activity.
PBL from 10 smoking and 10 nonsmoking healthy volunteers were isolated. Flow cytometry was performed to measure the state of activation, Fas expression and apoptosis of PBL. Functionality of Fas was tested by assessing apoptosis after incubation of isolated lymphocytes with agonistic anti-Fas antibodies in four smoking and four nonsmoking individuals.
Smoking was associated with an increase in the percentage of Fas-expressing CD4+ T and B lymphocytes. A decrease in the percentage of activated (CD38+) B cells was observed. In vitro Fas-induced apoptosis did not appear different between smokers and nonsmokers. No differences in the percentages of circulating apoptotic lymphocytes could be demonstrated between smoking and nonsmoking individuals. Conclusion Smoking is associated with increased Fas expression on PBL in general, and on B cells in particular. This might render these cells more susceptible for apoptosis. As Fas is functionally intact this may also explain the reduced percentage of activated (CD38+) B cells found in smoking individuals. The latter may contribute to the reduced humoral immune response observed in smokers.
In recent years disturbances in the process of apoptosis and the clearance of apoptotic cells have been put forward as fundamental in the development of autoimmunity. In this review we will discuss the data which supply evidence for this theory. We will focus on SLE as the prototype of autoimmune disease and will review both animal studies and clinical studies in SLE patients.
Maternal cigarette smoking during pregnancy is known to alter immune function in the offspring and recent studies with animals indicate that prenatal nicotine exposure leads to lasting deficiencies in T-lymphocyte mitogenic responses, likely through excessive cholinergic stimulation during a critical stage of development. The current study was conducted to determine if the vulnerable period for nicotine-induced mis-programming of immune responses extends into adolescence, the stage at which most smokers begin tobacco use. Adolescent rats were given nicotine via osmotic minipump infusions on postnatal days (PN) 30-47.5, using a regimen that produces plasma levels (25 ng/ml) of nicotine similar to those in smokers or in users of transdermal nicotine patches. Toward the end of the infusion period (PN45) and 1 month after termination of nicotine exposure (PN80), we examined the mitogenic responses of splenocytes to Concanavalin A. Although no deficiencies were seen on PN45, there were robust decreases in mitogenic responses on PN80, with deficits apparent at both suboptimal and optimal concentrations of Concanavalin A. These results indicate that the adolescent immune system is vulnerable to nicotine-induced disruption of T-cell function.
Levels of apoptotic lymphocytes have been found to be increased in SLE and persistence of apoptotic cells has been associated with autoantibody production. Increased lymphocyte Fas (CD95) expression due to lymphocyte activation may account for increased susceptibility to Fasmediated apoptosis in SLE.
Flowcytometry was performed to evaluate membrane expression of Fas in combination with the activation markers CD25, HLA-DR and CD38 on, respectively, CD4 ⁺ , CD8 ⁺ and CD19 ⁺ lymphocytes of SLE patients with inactive (n = 20) and with active disease (n = 13). SLEDAI-scores were calculated. Healthy volunteers (n = 14) served as controls.
Percentages of CD4 ⁺ T-cells expressing CD25 and CD19 ⁺ B-cells expressing CD38 were increased in patients with active disease compared to controls (P = 0.03, P = 0.04, respectively). In contrast to CD4 ⁺ and CD8 ⁺ cells, percentages of CD19 ⁺ cells expressing Fas were increased in SLE patients with active disease (P = 0.0002 vs controls). In these patients percentages of cells double positive for both CD38 and Fas were increased compared to patients with inactive disease (P = 0.006) and controls (P = 0.0007). Percentages of CD19 ⁺ cells expressing Fas correlated with SLEDAI-scores.
In SLE patients, percentages of Fas-expressing B-lymphocytes are increased, are related to the state of lymphocyte activation, and correlate to disease activity. Increased Fas expression results in a higher susceptibility for Fas-mediated apoptosis, which might contribute to the increased levels of apoptoticlymphocytes in SLE patients.
A cross-sectional study of deliveries in two districts in the Czech Republic, 1994-1996, assessed the relation between air pollution and lymphocyte immunophenotype distributions. Maternal and cord blood samples were assayed by flow cytometry within 24 hours of delivery for 303 deliveries from Teplice, a polluted district, and 215 from Prachatice, a less polluted district. Analyses focused on: CD3(+) T-lymphocytes, CD3(-) CD19(+) B-lymphocytes, and CD3(-) CD16(+)56(+) natural killer (NK) lymphocytes, as well as the subsets CD3(+)CD4(+) ("T-helper") and CD3(+)CD8(+) ("T cytotoxic/suppressor") and the ratio of these two lymphocytes. We collected reproductive, occupational, and life-style information by questionnaire, and abstracted data on labor and delivery from medical records. After adjustment for numerous risk factors in multivariate linear regression models fit for each lymphocyte subset, mothers from Teplice had lower percentages of total T-cells and of CD4(+) cells, and a lower ratio of CD4(+):CD8(+) cells. Cord bloods from Teplice had a higher percentage of NK cells and a less precise lower percentage of T-cells. Stronger differences in maternal lymphocytes were seen when analyses were limited to the central hospital in each district. Heavy air pollution may affect the immune system in pregnant women and/or fetuses, reflecting an acute and/or chronic effect, although unmeasured confounders could also play a role.
Interleukin-6 (IL-6) shares several biologic properties with IL-1, including hematopoietin-1 activity and stimulation of T cells. Because many of their biologic activities overlap, we developed and used a specific radioimmunoassay (RIA) for IL-6 to compare production of this cytokine on a molar basis with that of IL-1 alpha, IL-1 beta, and tumor necrosis factor (TNF)alpha. The RIA correlated well with the hybridoma bioassay for IL-6 (r = .87, P less than .001). Freshly isolated human peripheral blood mononuclear cells (PBMC) cultured in the absence of stimuli did not produce IL-6 in most cases. Kinetics of secretion and cell-association of IL-6 were studied. In contrast to IL-1 alpha but similar to TNF, IL-6 was almost entirely secreted into the extracellular fluid. Incubation with different stimuli (lipopolysaccharide [LPS], phytohemagglutinin [PHA], Staphylococcus epidermidis, or IL-1 alpha) resulted in production of IL-6. However, on a molar basis PBMC produced approximately two to three times less IL-6 than IL-1 alpha, IL-1 beta, or TNF, regardless of the stimulus. The amount of IL-6 produced from PBMC was consistent when measured in the same subjects six time during a 12-week period. In a cohort of 38 donors, the coefficient of variation for IL-6 production was .32, compared with .92 for IL-1 beta and .96 for TNF. Comparing cytokine production by PBMC, there was a significant correlation between IL-6 and IL-1 beta (r = .72) and between IL-6 and TNF (r = .66). IL-6 did not stimulate IL-1 beta or TNF production, but suppressed IL-1 beta and TNF production induced by LPS or PHA by 30% (P less than .01). This suppression of IL-1 beta and TNF by IL-6 appears to be on the level of transcription.
Interleukin-6 (IL-6) shares several biologic properties with IL-1, including hematopoietin-1 activity and stimulation of T cells. Because many of their biologic activities overlap, we developed and used a specific radioimmunoassay (RIA) for IL-6 to compare production of this cytokine on a molar basis with that of IL-1 alpha, IL-1 beta, and tumor necrosis factor (TNF)alpha. The RIA correlated well with the hybridoma bioassay for IL-6 (r = .87, P less than .001). Freshly isolated human peripheral blood mononuclear cells (PBMC) cultured in the absence of stimuli did not produce IL-6 in most cases. Kinetics of secretion and cell-association of IL-6 were studied. In contrast to IL-1 alpha but similar to TNF, IL-6 was almost entirely secreted into the extracellular fluid. Incubation with different stimuli (lipopolysaccharide [LPS], phytohemagglutinin [PHA], Staphylococcus epidermidis, or IL-1 alpha) resulted in production of IL-6. However, on a molar basis PBMC produced approximately two to three times less IL-6 than IL-1 alpha, IL-1 beta, or TNF, regardless of the stimulus. The amount of IL-6 produced from PBMC was consistent when measured in the same subjects six time during a 12-week period. In a cohort of 38 donors, the coefficient of variation for IL-6 production was .32, compared with .92 for IL-1 beta and .96 for TNF. Comparing cytokine production by PBMC, there was a significant correlation between IL-6 and IL-1 beta (r = .72) and between IL-6 and TNF (r = .66). IL-6 did not stimulate IL-1 beta or TNF production, but suppressed IL-1 beta and TNF production induced by LPS or PHA by 30% (P less than .01). This suppression of IL-1 beta and TNF by IL-6 appears to be on the level of transcription.
Human B-cell differentiation factor (BCDF) was purified to homogeneity by sequential filtration and chromatography of culture supernatants from TCL-Na1 cells on an AcA34 gel column and then on a Mono P column with fast protein liquid chromatography and reversed-phase HPLC. A 5300-fold enrichment in specific activity of BCDF with about 25% recovery was attained. The homogeneity of purified BCDF was evidenced by the following: (i) the specific activity was 1.7 X 10(7) units/mg of protein, (ii) only two bands, Mr 19,000 and 21,000, were identified by NaDodSO4/PAGE under reduced as well as nonreduced conditions, and (iii) BCDF activity was recovered from the gel after NaDodSO4/PAGE in the fractions corresponding to protein bands of Mr 19,000 or 21,000. Purified BCDF induced Ig secretion in Epstein-Barr virus-transformed cell lines; as little as 3 pM gave 50% of the maximum reaction achieved by 30-80 pM BCDF. Purified BCDF induced Ig production in activated B cells without any effect on cell growth. Purified BCDF did not show any activity of interleukin 1 or 2, B-cell stimulatory factor (BSF)p-1, B-cell growth factor II (BCGF-II), or interferon. Since BCDF was isolated and characterized as described, we propose that the BCDF that induces the final differentiation of B cells into high-rate Ig-secreting cells be designated BSFp-2.
The effect of prostaglandins and cyclic 3',5'-adenosine monophosphate (cAMP) on expression of human interleukin 1 (IL 1) activity was investigated in the promonocytic tumor cell line U937 and peripheral blood monocytes. After in vitro stimulation by bacteriotoxins, monocytes express IL 1 activity, as measured by the thymocyte costimulation assay. Although high doses of bacteriotoxins impaired expression of IL 1, this effect was reversed by indomethacin. When stimulated monocytes were cultured with exogenous prostaglandins, including PGE2 and PGI2, expression of IL 1 was reversibly inhibited. Interaction of U937 cells with PGE2 resulted in a transient increase in cellular cAMP concentration during the first hour of exposure. Other agents that cause an increase in levels of cellular cAMP, including theophylline, isobutylmethylxanthine, dibutyryl cAMP, or cholera toxin, also reversibly reduced expression of IL 1 by stimulated monocytes. The effect of these agents on levels of IL 1 mRNA was analyzed. TSS-stimulated increase in levels of IL 1-encoding mRNA was studied both by DNA-RNA hybridization analysis performed with an IL 1-beta cDNA probe and by injecting U937 polyadenylated mRNA into frog oocytes and then measuring expression of IL 1 activity in the oocyte supernatant. Agents that increased levels of cellular cAMP did not alter levels of IL 1 mRNA accumulation or global protein synthesis in TSS-stimulated U937 cells. IL 1 stimulates synthesis of prostaglandins that reach high levels during immune and inflammatory reactions. Our data suggest that prostaglandins participate in an autoregulatory pathway that posttranscriptionally reduces expression of IL 1 activity.
Growth and differentiation of thymocytes and mature T lymphocytes is regulated by cellular interactions that are in part mediated by soluble factors. We identify IL-6, formerly called B cell stimulating factor (BSF-2). IFN-beta 2, or hybridoma-plasmacytoma growth factor (HPGF) as a novel T cell costimulant rIL-6 induced a six-to seven-fold increase in proliferation of human thymocytes stimulated with suboptimal doses of PHA. A similar effect with added IL-6 could be observed using peripheral blood T lymphocytes, but only if the cultures were first rigorously depleted of monocytes that release high levels of IL-6. Analysis of the mechanism of the IL-6 effect on thymocytes and T lymphocytes showed that IL-6 did not lead to an increase in IL-2-R expression. Concentrations of antibody to IL-2-R inhibiting IL-2 effects did not block the IL-6-induced proliferation, indicating that the IL-6 effect was relatively IL-2 independent. These results identify IL-6 as a novel costimulant of human thymocytes and mature T lymphocytes, and suggest that IL-6 is also an important regulatory of cellular immunity.
Interleukin-6 (IL-6), a multifunctional cytokine produced in monocytes, fibroblasts, endothelial cells, and keratinocytes, is induced by a variety of stimulating signals, including lipopolysaccharide (LPS), poly (I), poly (C), IL-1, tumor necrosis factor (TNF), and platelet- derived growth factor. Some of these signals induce IL-6 effectively only in one cell type, and this selectivity of induction may explain selectivity of biologic effects. In the present study, we show that IL- 1 beta, previously known to be a potent inducer of IL-6 in fibroblasts, endothelial cells, and keratinocytes, but not in monocytes, is also a potent inducer of IL-6 in peripheral blood monocytes. High level IL-6 activity that could be neutralized by specific antibodies to IL-6 was detected in supernatants of IL-1-stimulated monocytes. Maximal induction required IL-1 concentrations of 10 ng/mL. As judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions, IL-6 species of relative molecular mass of 19 to 26 Kd could be specifically immunoprecipitated from supernatants of IL-1- induced monocytes. Size heterogeneity is a reported feature of IL-6 produced in a variety of cell types, and monocyte-derived IL-6 induced by either IL-1 or LPS displayed similar size heterogeneity. The highly purified recombinant IL-1 beta preparation used contained little, if any, LPS. In addition, monocyte production of IL-6, induced by IL-1 beta, was specifically neutralized by anti-IL-1 beta antibodies, demonstrating that IL-1, rather than a contaminant in the IL-1 preparation, was responsible for IL-6 induction. A number of biologic activities have been ascribed both to IL-1 and IL-6. The finding that IL-1 induced IL-6 in monocytes may help in defining the spectrum of biologic activities of each of these interactive cytokines.
Growth and differentiation of thymocytes and mature T lymphocytes is regulated by cellular interactions that are in part mediated by soluble factors. We identify IL-6, formerly called B cell stimulating factor (BSF-2). IFN-beta 2, or hybridoma-plasmacytoma growth factor (HPGF) as a novel T cell costimulant rIL-6 induced a six-to seven-fold increase in proliferation of human thymocytes stimulated with suboptimal doses of PHA. A similar effect with added IL-6 could be observed using peripheral blood T lymphocytes, but only if the cultures were first rigorously depleted of monocytes that release high levels of IL-6. Analysis of the mechanism of the IL-6 effect on thymocytes and T lymphocytes showed that IL-6 did not lead to an increase in IL-2-R expression. Concentrations of antibody to IL-2-R inhibiting IL-2 effects did not block the IL-6-induced proliferation, indicating that the IL-6 effect was relatively IL-2 independent. These results identify IL-6 as a novel costimulant of human thymocytes and mature T lymphocytes, and suggest that IL-6 is also an important regulatory of cellular immunity.
The development of a method providing an upper limit for the ETS contribution to indoor concentrations of RSP is reported. This upper limit is termed ultraviolet particulate matter (UVPM). Air is drawn at 2 L min through an inertial impactor separating at 3.5 μm, the RSP is collected on a membrane filter, and analyzed gravimetrically. Filters and collected material are then extracted in methanol, and the absorbance of the extraqt is measured spectrophotometrically at 325 nm. UVPM mass is computed from a calibration curve based upon ETS particulate matter collected in an environmental chamber.
Previous studies have shown that smoking is associated with a high incidence of certain malignancies and a high incidence of metastatic spread of melanoma. The purpose of the present study was to examine whether this high incidence of malignancy could be associated with certain aspects of immune function believed to be important in restricting tumour growth. Age-and sex-matched smoking and non-smoking normal subjects and male, smoking and non-smoking melanoma patients, were studied for the natural killing (NK) activity of their blood leukocytes against cultured melanoma and Chang cells. The levels of the various immunoglobulin classes in their sera and the E rosette levels of the normal subjects were also assessed. The results indicate that the NK activity of blood leukocytes from both normal subjects and melanoma patients who smoked was significantly lower against cultured melanoma cells than that of non-smokers. Smokers were also shown to have lower IgG and IgA Immunoglobulin levels in their sera compared to non-smokers but no differences in the percentage of E-rosetting (T) cells was detected. Recent studies provide some basis for the belief that the low NK activity and immunoglobulin levels in smokers may be related. These results further suggest that a closer examination of the effects of this environmental hazard on the immune system and its relation to malignancy is needed.
In order to provide information on levels of environmental tobacco smoke (ETS) in office environments during 1989, a total of 585 offices was sampled for a number of factors, including respirable suspended particles (RSP), nicotine, carbon monoxide, carbon dioxide, room size, average number of room occupants, and number of cigarettes consumed. Each data set was collected over a one-hour sampling period. Discriminant analysis of the data collected showed a group of rooms used for light smoking (59.9% of total smoking rooms) was not significantly different from the nonsmoking rooms, in terms of the variables which contributed to the predictive ability of the model (RSP and nicotine). These light-smoking rooms overlapped somewhat with the heavy-smoking rooms, suggesting other variables not measured here might contribute to this model, such as air change rates or outside air intake volumes. This leads to the possibility that a range of smoker densities could be established inside which indoor air quality will not be significantly affected, thus reflecting the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) Standard 62-89, which shows that with good ventilation acceptable air quality can be maintained with moderate amounts of smoking. Statistical analysis also showed overall levels of ETS in offices to be considerably lower than estimated in work ten years previously, and that carbon monoxide is only weakly influenced by smoking activity. Carbon dioxide measurements taken in each room did not correlate significantly with RSP, nicotine, or carbon monoxide, and there were significant relationships between smoker density, RSP, and nicotine, respectively.
A rapid gas-liquid chromatographic method for the estimation of nicotine in plasma is described. Nicotine is extracted from alkalinized plasma into diethyl ether. This is then concentrated by evaporation and, after an acid back extraction is re-extracted into n-heptane (nitrogen detector) or dichloromethane (flame ionization detector) before injection onto the gas chromatography. Thirty samples a day can be analysed by this method which enables concentrations of 0.1 ng ml- minus 1 nicotine to be measured. It is thus possible to measure nicotine in plasma and urine samples from non-smokers.
Attention is drawn to the long-term effects of atmospheric contaminants in general (and cigarette smoke in particular) on immunological control mechanisms that are accepted as playing a vital role in the maintenance of health. The review argues that a hostile environment within the respiratory tract created by inhalation of air contaminants compromises local immunological function in the short term, and ultimately depresses systemic immunological function. Whether such a decline in immunological homeostasis is due directly to toxicity, or indirectly to accelerated aging of susceptible elements of the immune system, is speculative. The changes observed in both man and experimental animals exposed for long periods to air contaminants in many respects parallel those associated with normal aging and may represent an acceleration of the process of senescence. Specific biological effects of smoking, air pollution and immune functions in man and animal models are reviewed. The precise mechanism(s) by which air contaminants affect immunological function remains speculative, but the relative resistance of specified-pathogen-free animals to these agents infers a central role for the hosts' normal bacterial flora in the process.
We evaluated the ability of human pulmonary alveolar macrophages (PAMs) to mediate (3H)-thymidine incorporation by blood lymphocytes severely depleted of monocytes when stimulated with soluble microbial and allogeneic lymphocyte antigens. Low (less than 2%) concentrations of PAM's from nonsmokers or blood monocytes did not support optimal responses. Over all, at greater than or equal to 10% concentrations, PAM's from nonsmokers supported higher responses than monocytes. At less than or equal to 10% concentrations, PAM's from heavy cigarette smokers mediated significantly less incorporation than did similar concentrations of PAM's from nonsmokers (p less than 0.05). The findings indicate that PAM's from healthy nonsmokers are functionally competent macrophages in terms of mediating lymphoproliferation in cultures stimulated with antigens. This classical macrophage function is impaired with cigarette smoking.
It may be established that the complex cardiopulmonary functional diagnostics in patients with chronic ischaemic heart disease obtained the following essential results: 1. The ergometrically achieved total functional capacity is clearly decreased in all age groups compared with the healthy persons, the differences are highly significant. 2. The proof of a coronary insufficiency got by the electrocardiogram after work is to be regarded as a factor limiting the functional capacity. 3. 72% of the patients reveal under load a PAEDP increased more than the normal of 25 Torr. After exclusion of a respiratory insufficiency these findings must be regarded as a disturbed myocardial function. 4. Thus the increased PAEDP under load apart from the well-known triad (angina pectoris under load, decreased total functional capacity, pathological ECG after work) is a sensitive and decisive factor for proving the disturbed cardial function in chronic ischaemic heart disease.
CD14 is a 53-kd glycoprotein that is mainly expressed in myeloid cells and exists in two forms. The membrane-bound form represents the receptor for complexes of lipopolysaccharide (LPS) with LPS binding protein. The function and regulation of the soluble form are unknown. In the present study we investigated the release of soluble CD14 (sCD14) in cultures of human mononuclear leukocytes, elutriated monocytes, and monocyte-derived macrophages. The release of sCD14 into the medium of the cells cultured for 15 and 45 h was investigated in the absence or presence of selected cytokines. sCD14 release occurred constitutively and correlated with cell number. In monocytes differentiating into macrophages, cumulative release of sCD14 was linear from day 1 to day 7. Spontaneous sCD14 release after 15 h of culture (2 x 10(6) cells/ml) was higher in the supernatant from monocytes (314 +/- 58 ng/ml) than that from mononuclear leukocytes (68 +/- 10 ng/ml) and similar to that from macrophages (469 +/- 79 ng/ml). Cycloheximide and actinomycin D inhibited sCD14 release. Recombinant interferon-gamma (rIFN-gamma) and recombinant interleukin-4 (rIL-4) directly decreased sCD14 release in mononuclear leukocyte, monocyte, and macrophage cultures. rIL-2 and rIFN-alpha reduced sCD14 release into the supernatants of mononuclear leukocytes only. Use of anti-IFN-gamma antibodies indicated that the down-regulation of sCD14 release by rIL-2 and rIFN-alpha was partially due to induction of endogenous IFN-gamma. The down-regulation of sCD14 release by all four cytokines was both time and dose dependent. rIFN-gamma and rIL-4 added simultaneously had a synergistic effect on sCD14 down-regulation. In conclusion, sCD14 release may have an immunomodulatory role in circulating monocytes, is apparently not related to the process of macrophage differentiation, and is selectively down-regulated during an immune response when levels of IFN-gamma and IL-4 are high.
Studies suggest smokers have decreased alveolar macrophage (AM) accessory cell (AC) function and a reduced incidence of immune-mediated lung diseases such as sarcoidosis. Impaired AM secretion of cytokines important in T-cell immune responses could explain this observation. We investigated production and secretion of interleukin-1 (IL-1) and interleukin-6 (IL-6) in smokers and nonsmokers. Lipopolysaccharide-induced AM IL-1 secretion in smokers was significantly reduced compared with nonsmoker AM. However, intracellular IL-1 in smoker AM was higher than in nonsmokers, suggesting that reduced IL-1 secretion was due to impaired release rather than reduced production. Smoker AM secreted significantly less bioactive IL-6 measured in a bioassay compared with nonsmoker AM. Intracellular IL-6 was virtually undetectable in both groups. In some smokers IL-6 production determined by immunoprecipitation was reduced. However, as a group antigenic IL-6 secretion determined by enzyme-linked immunoabsorbent assay was similar in smokers and nonsmokers, suggesting that smoker AM may cosecrete an inhibitor of IL-6 bioactivity. Indeed, AM supernatants from smokers inhibited B9 proliferation in response to maximal recombinant IL-6 stimulation, whereas supernatants from nonsmokers did not. We conclude that AM from smokers secrete less cytokines important in T-cell proliferation than AM from nonsmokers and suggest that for IL-6 this impairment is related to both decreased production of antigenic protein as well as cosecretion of an IL-6 inhibitor.
Murine anti-CD14 mAb which recognize different CD14 epitopes induced marked homotypic adhesion of normal human monocytes. Induction of aggregation by anti-CD14 mAb required Mg2+, occurred at an optimal temperature of 37 degrees C, but not at 4 degrees C, and exhibited a kinetics which differed from adhesion triggered by IFN-gamma and anti-CD43 mAb. Monocyte adhesion induced by anti-CD14 mAb required neither Fcy gamma R engagement nor cross-linking of CD14, because adhesion was induced by F(ab)'2 fragments, as well as by monovalent F(ab) fragments of anti-CD14 mAb. mAb to CD11a, CD18, and intercellular adhesion molecule-1 (ICAM-1), but not antibodies to CD11b and CD11c, inhibited monocyte adhesion induced by CD14 engagement. These results indicate that CD14-dependent adhesion is mediated by lymphocyte function-associated Ag-1/ICAM-1 interactions. This was confirmed by the absence of aggregation in anti-CD14-stimulated cells from a patient with leukocyte adhesion deficiency. Monocyte adhesion upon CD14 engagement was blocked by an inhibitor of protein kinases, sphingosine. This suggests that protein kinases play a role in the intracellular signaling pathway(s) which couple CD14 to lymphocyte function-associated Ag-1/ICAM-1.
The influence of cigarette smoking on T cell subsets has been studied in white subjects, but comparable data are not available for blacks. We analyzed peripheral blood mononuclear cell subsets in a population-based, stratified, random sample of healthy black adults using monoclonal antibodies and flow cytometry. The study population consisted of 94 men and 79 women, including 73 smokers (CS) and 100 nonsmokers (NS). Cigarette smoking was associated with a significant elevation in leukocyte (WBC) count (CS 7,270 +/- 230 cells/mm3 versus NS 6,260 +/- 160 cells/mm3; p = 0.001), although WBC counts for both groups were substantially lower than those reported for white smokers and nonsmokers. Smokers had a significantly lower proportion of CD4+ cells than nonsmokers (CS 55.4 +/- 0.9% versus NS 58.7 +/- 0.9; p = 0.01), adjusting for age and gender. No significant smoking-related changes were observed for CD8+ cells, the CD4/CD8 ratio, or total T cells (CD3+), monocytes (CD14+), or natural killer cells (CD16+). Among black smokers, a significant dose-related decrease in CD4+ cells was observed as the number of cigarettes smoked per day increased. Among black exsmokers, the level of WBC and CD4+ cells returned to the level observed in never smokers within 2 to 5 yr after smoking cessation. These results contrast sharply with the previously reported increase in CD4+ cells and decrease in natural killer cells associated with cigarette smoking in whites. The data suggest that the immunologic effects of cigarette smoking may be significantly modified by ethnic characteristics.
Maturation of cytolytic T lymphocytes from nonlytic precursors requires cytokines in addition to IL2. Interleukin-6 is the principal cytokine that cooperates with IL2 in the induction of CTL differentiation from murine and human thymocyte precursors. However, a cytotoxic differentiation factor (CDF) role of IL6 for mature T cells is challenged by data indicating that IL2 alone is sufficient for CTL generation. The aim of this study was to identify a model system in which IL6 acted as a CDF for human peripheral T cells. We noted that IL6 was endogenously produced by CTL clones in the course of their expansion with APC, lectin, and IL2. The majority of several hundred T-cell clones, both CD4+ and CD8+, produced IL6 in response to relatively high doses of IL2. Other experiments that compared the cytolytic function of CTL clones cultured in the presence of IL6 with that of the same clones cultured in the absence of IL6 demonstrated that IL6 contributes to the cytolytic ability of the majority of human CTL clones. Our data suggest that IL6 acts in an autocrine fashion to support CTL differentiation in human T-cell clones.
A rapid method is described for the simultaneous measurement of nicotine and cotinine in biological fluids using capillary column gas-liquid chromatography. Using 100 microliters sample volume the lower limit of detection for both nicotine and cotinine was 100 pg mL-1, allowing the method to be used for the measurement of these compounds in both smokers and non-smokers. The extraction time is 3 min per sample, and by using multi-pipetting and vortexing systems 250 samples can be extracted per day. The average coefficient of variation over the nicotine range 1.0 to 100 ng mL-1 was 3.9% and for cotinine over the range 1.0 to 1000 ng mL-1 was 2.2%. Saliva cotinine concentrations were quantitatively related to passive exposure to parental smoking in a population study of 1118 non-smoking schoolchildren.
This review evaluates the available information on the effects of mainstream and environmental tobacco smoke on the immune system in animals and humans. The primary emphasis is on mainstream smoke since little information is available on the effects of environmental smoke. The effects of mainstream tobacco smoke on the immune system in humans and animals are similar. Animals exposed to mainstream tobacco smoke for periods of a few weeks generally exhibit a slight immunostimulation. However, subchronic and chronic exposure studies indicate that immunosuppressive changes develop. Lymphocyte proliferation in response to the mitogens PHA and LPS is decreased, suggesting compromise of cell function. Antibody production can be suppressed. Smoke-exposed animals that are challenged with metastasizing tumors or viruses have been shown to exhibit a higher incidence of tumorigenic and infectious diseases, respectively. Localized immunological changes in the lung can include reduction of bronchus-associated lymphoid tissue and immunoglobulin levels. Smoking-related changes in the peripheral immune system of humans have included elevated WBC counts, increased cytotoxic/suppressor and decreased inducer/helper T-cell numbers, slightly suppressed T-lymphocyte activity, significantly decreased natural killer cell activity, lowered circulating immunoglobin titers, except for IgE which is elevated, and increased susceptibility to infection. The effects of environmental tobacco smoke on the immune system, in contrast to mainstream tobacco smoke, have just begun to be investigated and information available in the literature, to date, is limited. Immunoreactive substances are known to be present in environmental tobacco smoke, but to date, environmental tobacco smoke has been more closely associated with irritation than sensitization. A few studies have indicated a potential for environmental smoke-induced hypersensitivity and suppression of immunoregulatory substances. In contrast, other investigators have failed to detect immunological or other biological changes associated with environmental smoke. Clearly, more research is needed to resolve these differences.
Reduced cell-mediated immune function has been found in depressed patients and in distressed persons undergoing threatening life events. The present study examines the interaction between severe life stress and major depression to produce immune alterations in 36 matched pairs of hospitalized depressed patients and nondepressed controls. Both major depressive disorder and the presence of threatening life events in control subjects are independently associated with a 50% reduction of natural killer (NK) cytotoxicity. A decrease in natural cytotoxicity is significantly associated with depressive symptoms but not with age, alcohol consumption, or tobacco smoking. These findings of altered immunity provide further evidence that the physiological responses in chronic stress parallel those found in the syndrome of depression.
Interleukin-6 (IL-6), a multifunctional cytokine produced in monocytes, fibroblasts, endothelial cells, and keratinocytes, is induced by a variety of stimulating signals, including lipopolysaccharide (LPS), poly (I), poly (C), IL-1, tumor necrosis factor (TNF), and platelet-derived growth factor. Some of these signals induce IL-6 effectively only in one cell type, and this selectivity of induction may explain selectivity of biologic effects. In the present study, we show that IL-1 beta, previously known to be a potent inducer of IL-6 in fibroblasts, endothelial cells, and keratinocytes, but not in monocytes, is also a potent inducer of IL-6 in peripheral blood monocytes. High level IL-6 activity that could be neutralized by specific antibodies to IL-6 was detected in supernatants of IL-1-stimulated monocytes. Maximal induction required IL-1 concentrations of 10 ng/mL. As judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions, IL-6 species of relative molecular mass of 19 to 26 Kd could be specifically immunoprecipitated from supernatants of IL-1-induced monocytes. Size heterogeneity is a reported feature of IL-6 produced in a variety of cell types, and monocyte-derived IL-6 induced by either IL-1 or LPS displayed similar size heterogeneity. The highly purified recombinant IL-1 beta preparation used contained little, if any, LPS. In addition, monocyte production of IL-6, induced by IL-1 beta, was specifically neutralized by anti-IL-1 beta antibodies, demonstrating that IL-1, rather than a contaminant in the IL-1 preparation, was responsible for IL-6 induction. A number of biologic activities have been ascribed both to IL-1 and IL-6. The finding that IL-1 induced IL-6 in monocytes may help in defining the spectrum of biologic activities of each of these interactive cytokines.
Surface phenotypes of lymphocytes and the assessment of cytotoxic NK activity were determined in peripheral blood leukocytes in a group of heavy smokers and respective non-smoking people control group. Cell phenotypes were evaluated by a panel of monoclonal antibodies by indirect immunofluorescence on cell sediments. Cytotoxic activity was assessed by single cell cytotoxic assay on target K 562 cells. There were no significant differences in T cell (CD 3+) as well as in CD 43+ ones (large sialoglycoprotein) per cent values. The cells possessing receptor for sheep red blood cell (CD 2+) were however more numerous in smokers as compared to non-smokers. Per cent value of B lymphocytes in the former group was significantly decreased vs control one. There was no difference in per cent values of activated and immature cells in both examined groups. Per cent values of NK cell activity were higher in non-smokers in relation to smokers. It was reflected by an increase of cytotoxicity of effector cells, while frequency of incidence of NK cells was comparable in both groups examined.
Analysis of the functional activity of phagocytes is of great importance in the differential diagnosis of patients with recurrent bacterial infections. Here we describe a method to determine the production of reactive oxygen intermediates (ROI) by microcytofluorometry using dihydrorhodamine 123, a derivative of rhodamine 123. Using this method the ROI production of erythrocyte-depleted whole blood samples can be measured without further time-consuming purification steps. Possible harmful manipulation of the isolated cells can also be avoided and highly reproducible and significant results are obtained in the minimum of time. This assay provides a very sensitive alternative to the clinically used NBT test in the diagnosis of patients with chronic granulomatous disease (CGD). Moreover, the analysis of oxygen-dependent effector functions of murine effector cells and cell lines may be important in investigating resistance to certain microbes (e.g., Candida albicans, Staphylococcus aureus or different protozoa such as Toxoplasma gondii or Leishmania species).
An anti-CD14 mAb RoMo-1 rapidly induces in human monocytes a transient oxidative burst activity as detected by chemiluminescence assay. Pretreatment of these cells with the mAb markedly suppresses the monocyte chemiluminescence response to opsonized zymosan. In addition, the antibody induces a significant increase of IL-1 production and secretion by mononuclear cells, comparable to a similar effect of rIFN-gamma or LPS. Electron microscopy demonstrates internalization of the CD14 molecules after interaction with the mAb in a characteristic receptor-like manner.
Alveolar macrophages (AM) can play a crucial role in the pathogenesis of pulmonary disease via their ability to produce potent inflammatory and fibrogenic mediators. We found that rat AM cultured with 1 to 100 micrograms/ml of silica particles or asbestos fibers produced tumor necrosis factor (TNF) and leukotriene B4 (LTB4) in a concentration-dependent fashion, whereas latex beads, an inert phagocytic stimulus, failed to induce significant augmentation of either TNF or LTB4. In a time course study, AM stimulated for 2 h with silica or asbestos produced an increased amount of LTB4, which preceded the rise in TNF activity detected 7 and 24 h after culture initiation. The induction appears to involve the synthesis of new protein since actinomycin D and cycloheximide abrogate the majority of the stimulatory effect. We next examined the role of LTB4 in mineral-dust-induced TNF production. The lipoxygenase inhibitors nordihydroguaiaretic acid (NDGA) and AA861 used at 1 to 50 micrograms/ml reduced in a concentration-dependent fashion asbestos- or silica-stimulated TNF release. On the other hand, "reconstitutive" experiments in which we added exogenous LTB4 (10(-14) to 10(-8) M) to AM treated with lipoxygenase inhibitors showed partial restoration of TNF production induced by chrysotile or silica, with peak effect at 10(-10)M LTB4. The present study demonstrated that AM incubated in the presence of chrysotile A or silica can produce both LTB4 and TNF and that endogenous lipoxygenase metabolites as well as exogenous LTB4 can act to amplify TNF production. These observations suggest a common mechanism by which asbestos and silica may modulate the production of inflammatory and fibrogenic cytokines.
Purified T cells can be induced to proliferate and to produce the autocrine growth factor IL-2 with mAb to the TCR and costimulatory cytokines. In a previous report we demonstrated that human IL-6 stimulates IL-2 production and proliferation of purified T cells, in conjunction with the insolubilized anti-TCR V beta 8 mAb, F23.1. Here we show that when CD4+ T cells are rigorously purified to greater than 99% CD4+CD8-, they respond only weakly to F23.1 and IL-6. Instead, there is an additional requirement for IL-1, which dramatically synergizes with IL-6 to induce prolonged (greater than 7 days) proliferative responses and IL-2 production. Similar results were observed when the highly mitogenic anti-CD3 mAb 145-2C11 was substituted for F23.1. The proliferation induced by F23.1, IL-1, and IL-6 was substantially (greater than 80%) inhibited by a mAb to mouse IL-2, and was not inhibited by an anti-IL-4-mAb. In accordance with this finding, medium conditioned by the activated CD4+ cells contained large amounts of IL-2, which increased over a 7-day culture period. These results demonstrate that IL-6 and IL-1 stimulate T cell proliferation by inducing production of the autocrine growth factor IL-2. In addition, the two lymphokines must be present simultaneously for activation to occur. The possible roles of IL-6 and IL-1 in IL-2 gene regulation and in Ag-induced T cell activation are discussed.
A gas chromatographic method for determination of vapor phase nicotine in environmental tobacco smoke (ETS) was collaboratively studied by 6 laboratories. Nicotine is desorbed from XAD-4 sample tubes with ethyl acetate containing triethylamine and determined by gas chromatography with nitrogen-selective detection. Each collaborator received blind duplicate samples at each of 6 nicotine concentrations. Three concentrations were generated by spiking XAD-4 tubes with known amounts of nicotine; the remaining 3 concentrations were ETS samples obtained in a carefully controlled environmental chamber containing sidestream and exhaled mainstream smoke from 1R4F Kentucky reference cigarettes. Repeatability and reproducibility relative standard deviations ranged from 4.4 to 11.1% and from 7.0 to 11.1%, respectively, for nicotine concentrations evaluated (up to 6 micrograms/cu m). The method has been adopted official first action.
Measurement of the dose received from passive smoking complements epidemiological approaches and may provide an alternative method of estimating risk. Non-smokers absorb measurable amounts of nicotine from breathing other people's smoke, and dose-response relationships are apparent. On the basis of the limited data so far available, the dose of nicotine received by the average British non-smoker may represent about 0.5% of that of the heavy cigarette smoker, ranging up to 2% in more heavily exposed individuals. The dose of carbon monoxide appears relatively greater, as does that of tobacco-specific nitrosamines. The situation with respect to tar is unclear, but nicotine may provide a better guide than does CO.
We characterized the ability of normal human lung fibroblasts to elaborate thymocyte-stimulating activity, spontaneously, and in response to rIL-1. Supernatants from unstimulated fibroblasts did not contain thymocyte-stimulating activity, whereas supernatants from fibroblasts incubated with rIL-1 alpha or rIL-1 beta contained more thymocyte-stimulating activity than could be accounted for by passively transferred rIL-1 alone. This heightened thymocyte-stimulating activity was mediated by fibroblast-derived IL-6 inasmuch as it was neutralized by anti-serum against human rIL-6, and rIL-1-stimulated fibroblasts to accumulate messenger RNA for IL-6 and produce soluble IL-6 protein. However, IL-6 alone could not account for the intensity of this effect because rIL-6 only weakly stimulated thymocyte proliferation. In addition, antisera against the rIL-1 moiety that was used to prepare the supernatant had different effects on supernatants that contained and did not contain active IL-6. In the presence of IL-6 these antisera caused a greater decrease in thymocyte-stimulating activity than could be accounted for by passively transferred rIL-1 alone. When the IL-6 was neutralized the remaining thymocyte-stimulating activity could be quantitatively accounted for and neutralized by antisera against the rIL-1 that was passively transferred. Furthermore, rIL-6 and rIL-1 (alpha or beta) synergized in stimulating thymocyte proliferation. Thus, rIL-1 stimulates fibroblasts to produce a thymocyte-stimulating activity that is largely mediated by a synergistic interaction of fibroblast-derived IL-6 and IL-1. These findings suggest that fibroblast production of IL-6 may mediate or amplify some of the tissue effects of IL-1. In addition they suggest that biologic effects previously attributed to IL-1 may be due to IL-6 alone or the concerted action of IL-1 and IL-6.
To determine whether alveolar macrophages from smokers have an abnormal interleukin 1 beta (IL-1) release, we obtained macrophages by bronchoalveolar lavage (BAL) of otherwise healthy volunteers in three groups: nonsmokers (NS; n = 11), light smokers (LS, less than 10 pack-yr smoking history; n = 4) and heavy smokers (HS, greater than 10 pack-yr smoking history; n = 9). After 24 h in culture, unstimulated macrophages (from each group) released negligible amounts of IL-1. Lipopolysaccharide (LPS) (1 micrograms/ml) caused release of 21.77 +/- 4.33 ng IL-1/10(6) cells at 24 h from NS macrophages; IL-1 release from HS macrophages was significantly decreased (5.52 +/- 1.66 ng/10(6) cells; P less than 0.05), whereas LS macrophages released intermediate amounts (15.07 +/- 6.15 ng/10(6) cells). Release of IL-1 from HS macrophages was also decreased after 48 and 72 h in culture and was observed over a wide range of concentrations of LPS. The decreased amount of IL-1 in HS macrophage supernatants appeared to be due to a defect in release of IL-1 from the cells and not due to a defect in production of the mediator, since total IL-1 (IL-1 present in the cell lysates plus that in the cell supernatants) was similar in the NS and HS groups. In addition, after 24 h in culture, LPS-stimulated HS macrophages released significantly less prostaglandin E2 (PGE2) (which can suppress IL-1 production) than did NS macrophages; in the presence of indomethacin, which abolished macrophage PGE2 release, no augmentation of LPS-stimulated IL-1 release was observed. Cell viability, as measured by lactate dehydrogenase release, was not different between HS and NS macrophages under any conditions. We conclude that there is a defect in release but not production of IL-1 from the alveolar macrophages of chronic smokers.
To investigate the influence of cigarette smoking on mononuclear cell subsets, we determined T cell, B cell, monocyte, and HLA-DR+ subsets in a population-based, stratified, random sample of healthy Caucasians using monoclonal antibodies and flow cytometry. The study population consisted of 282 subjects 20 to 69 yr of age, including 108 smokers and 174 nonsmokers. Multivariate analysis techniques were used to assess the influence of cigarette smoking status after controlling for the effects of age and gender. Cigarette smoking was associated with a nonspecific increase in the leukocyte count involving all major cell types (smokers: 8.50 +/- 0.15 versus nonsmokers: 7.33 +/- 0.12 cells/mm3; p less than or equal to 0.0001). In addition, cigarette smokers had a selective increase in CD4+ cells (helper-inducer T cells) compared with nonsmokers (55.3 +/- 0.8 versus 52.2 +/- 0.6% of lymphoid cells; p = 0.002), resulting in a statistically significant increase in the CD4+/CD8+ (helper/suppressor) ratio (2.42 +/- 0.1 versus 2.13 +/- 0.16; p = 0.02). There was no significant difference between smokers and nonsmokers in the level of CD3+ cells (total T cells: 76.8 +/- 0.7 versus 76.1 +/- 0.5; p = 0.5), CD8+ cells (suppressor-cytotoxic T cells: 25.7 +/- 0.8 versus 27.0 +/- 0.5%; p = 0.1), CD19+ cells (B cells) (10.7 +/- 0.4 versus 10.0 +/- 0.3%; p = 0.2), CD14+ cells (monocytes) (18.0 +/- 0.6 versus 17.0 +/- 0.4%; p = 0.2), or HLA-DR+ cells (14.5 +/- 0.5 versus 14.0 +/- 0.4%; p = 0.4).(ABSTRACT TRUNCATED AT 250 WORDS)
To evaluate the mechanism by which cigarette smoking suppresses pulmonary immune responses, we determined the capacity of alveolar macrophages (AM) to produce interleukin 1 (IL-1 in 32 normal subjects and in 40 patients with pulmonary sarcoidosis. The amount of IL-1 released from LPS-stimulated AM from smokers was significantly decreased compared with that in nonsmokers in both normal and sarcoid groups. The addition of indomethacin to the cultures in 18 normal subjects and in 22 patients with pulmonary sarcoidosis yielded similar results, thus excluding the possibility that this difference resulted from a difference in the amount of cyclooxygenase metabolites released in the culture supernatants. Similar results were obtained by enzyme-linked immunosolvent assay. Because IL-1 is thought to induce the accumulation of T cells at the site of disease and contribute to local cellular and humoral immunity of the lung, our data suggest that the reduced capacity of AM to release IL-1 in smokers affords partial protection against the initiation of immune responses in the lung and the development of granulomatous lung diseases.
The function of alveolar macrophages (AM phi s) was studied in terms of the secretion of various chemotactic factors. Human AM phi s were obtained by BAL from healthy non-smokers and smokers. One of the chemotactic factors was LTB4, an arachidonic acid metabolite of the lipoxygenase pathway. The amount of LTB4 was determined in culture medium, in cell homogenate and in BAL-fluid. The total chemotactic activity for neutrophils was measured in culture medium and in BAL-fluid. AM phi s from smokers showed an impaired secretion of LTB4. The spontaneous secretion in vitro was inhibited by 90% (p less than 0.05) and the stimulated one was blocked by 84% (p less than 0.05). This impairment was not followed by a decrease in total chemotactic activity, indicating the existence of other chemotactic factors than LTB4. Preliminary characterization of the chemotactic activity by gel filtration demonstrated at least four different chemotactic factors. Budesonide inhibited both the release of LTB4 and the total chemotactic activity in medium from stimulated AM phi s.
Soluble products of either Epstein-Barr virus (EBV)-infected B cells or activated monocytes promote the proliferation of EBV-infected
B cells and permit their growth at low cell densities. This suggests that growth factors are important for B-cell immortalization
by EBV. In this study, a monocyte-derived factor that promotes the growth of EBV-infected b cells was purified and identified
as interferon-beta 2 (IFN-beta 2), which is also known as 26-kilodalton protein, B-cell differentiation factor (BSF-2), and
interleukin-6 (IL-6). The purified protein has a specific activity of approximately 4 X 10(7) units per milligram of protein
in assays of B-cell growth. Thus, IFN-beta 2/BSF-2 is a B-cell growth factor that promotes the proliferation of human B cells
infected with EBV.
Human alveolar macrophages and peripheral blood monocytes were obtained from smoking and nonsmoking normal volunteers. The macrophages and monocytes were incubated in vitro with bacterial lipopolysaccharide (LPS). The oxidative metabolic response of these cells was measured by superoxide anion production. Macrophages from smokers were suppressed in their superoxide anion response to LPS activation as compared to macrophages from nonsmokers. Monocytes from smokers and nonsmokers were not different. The cytotoxic properties of these macrophages and monocytes were assessed by an in vitro 3H-thymidine release assay against various allogeneic target cells. Macrophages and monocytes exposed to LPS were rendered tumoricidal. Macrophages from nonsmokers appeared to generate greater cytotoxic activity than macrophages from smokers. Macrophages from both smokers and nonsmokers were cytotoxic for three different tumorigenic cell lines but not for a nontumorigenic cell line. Monocytes from smokers and nonsmokers were not different in cytotoxic activity. We conclude that macrophages from both smokers and nonsmokers can be activated after exposure to LPS; however, macrophages from smokers may be slightly suppressed in their responses.
To investigate the relationship between cigarette smoking and the level of circulating natural killer (NK) cells, we studied 282 subjects from a population-based, stratified random sample of healthy persons. NK cells were enumerated by flow cytometry using the monoclonal antibody anti-Leu 11A. Cigarette smokers had a significantly lower proportion of NK cells than did subjects who had never smoked (5.5 +/- 0.3% versus 7.4 +/- 0.4% of lymphoid cells; p = 0.0002). NK cells were also decreased among ex-smokers (5.6 +/- 0.4%; p = 0.002), including subjects who had not smoked for more than 20 yr. The white blood cell and lymphocyte counts were increased in smokers compared with those in never smokers (p less than 0.0001). In contrast to NK cells, the smoking-related changes in leukocyte count were not present in ex-smokers, even those who had stopped smoking within the past year. Multivariate analysis confirmed that both current and past smokers had significant decreases in both the number and proportion of NK cells after controlling for age, sex, and lymphocyte count. These data indicate that cigarette smoking is associated with a decrease in the number and proportion of circulating NK cells, and that this effect is present many years after smoking cessation. This quantitative NK cell deficit may contribute to the elevated risk of malignancy in this population.
Simultaneous numerical and functional studies of circulatory lymphocytes were undertaken in healthy non-smoking and cigarette-smoking volunteers. The smokers all had light to moderate histories of less than 50 pack years. By contrast with non-smokers (n = 32), the smokers (n = 14) had a significant increase in the total number of lymphocytes, surface immunoglobulin bearing (sIg+) cells, total T-cells (T3+) and T helper-inducer cells (T4+), and a trend of increase in T suppressor-cytotoxic cells (8+). These changes differ from those in heavy smokers who have been reported to show significantly increased T suppressor-cytotoxic but significantly decreased T helper-inducer cells. Although the proportions of T-cell subsets did not differ significantly in the light to moderate smokers compared with non-smokers, in vitro T-suppressor function against the Ig-secreting response of allogeneic B-cells to pokeweed mitogen (PWM) stimulation was significantly impaired. The proliferative response of T-cells to phytohaemagglutinin (PHA) was, however, similar in both groups. This suggests that smoking may exert a selective influence upon a subset of T suppressor cells. In cytotoxicity assays, smokers showed a significant decrease in natural killer cell (NK) activity but not in antibody dependent cellular cytotoxicity (ADCC). It appears that these alterations are reversible since a group of ex-smokers (n = 10) were indistinguishable from our non-smoking group in all studies. The implications regarding the link between smoking and increased susceptibility to infection and malignancy are discussed; and these findings should be borne in mind in basic studies of lymphocytes.
Immunotoxicity is defined as the adverse effects of foreign substances (xenobiotics) on the immune system. Two types of effects are possible: immunosuppression (which may result in an increased susceptibility to infection or to the development of tumours) and immunopotentiation (which may manifest as an allergy or as autoimmunity). There is, as yet, little evidence that well controlled occupational exposure to industrial chemicals has led to clinically significant immunosuppression. In contrast, a number of industrial chemicals have been shown to cause immunopotentiation in exposed populations, producing occupational asthma and contact dermatitis and possibly autoimmunity. In experimental models, immunosuppression (usually assessed by in vivo or in vitro immune function tests) has been induced by a wide range of chemicals but there are a few reports of the immunosuppression leading directly to an increased susceptibility to infection or to the development of tumours. Predictive experimental models are available for type IV allergic reactions, but the identification of chemicals that have a potential to cause other types of allergy or autoimmune reactions requires further research and the development and validation of new animal models. It is considered that routine subacute and chronic toxicity studies should include a full gross and histopathological assessment of the lymphoid organs to more accurately detect the potential of a chemical to cause immunotoxicity. Should such studies indicate that a substance has affected the immune system directly, an assessment of overall immune competence and function tests may be necessary using dose levels below those which cause frank toxicity. However, precise interpretation of immune function tests in terms of their relevance to human health requires an improved understanding of the extent of the functional reserve of the immune system. A strategy for assessing immunotoxicity in exposed human populations demonstrates a need for reliable clinical assessment, accurate medical record-keeping, an environmental and biological monitoring for levels of contaminating chemicals and the judicious use of well-validated immune function tests.
To evaluate the activation of alveolar macrophages from smoking, we studied interleukin-1 (IL-1) activity released from alveolar macrophages in eight healthy smokers, compared to 12 healthy nonsmokers. We used 24-hour culture supernatants containing IL-1 of bronchoalveolar lavage fluid (BALF) macrophages/blood monocytes with or without LPS stimulation. Using C3H/HeJ thymocyte PHA costimulation assay, we found that IL-1 activity released from LPS stimulated BALF macrophages was significantly higher in smokers (2.39 +/- 0.33 U/ml) than in nonsmokers (1.47 +/- 0.19 U/ml, p less than 0.05). We also detected IL-1 inhibitory activity in supernatants by using IL-1 inhibitory assay. The inhibitory activity was higher in nonsmokers than in smokers especially under LPS stimulation. The presence of inhibitory factors other than prostaglandin-E2 was suggested from the differential response to the addition of indomethacin into cultures from nonstimulated and LPS-stimulated supernatants of BALF macrophages.
We investigated the effect of smoking on natural killer (NK) cell activity and distribution in bronchoalveolar lavage fluid (BALF) and blood. Initially, BALF NK cell activity was lower than the blood NK cell activity both in non-smokers (NS) and smokers (S). Following 24 hour culture, NK cell activity markedly increased in NS but not in S. Percentage distribution of Leu-7+ cells and Leu-11+ cells in BALF was similar in NS and S. But the BALF NK cell activity was significantly augmented by IL-2 or OK-432 (a streptococcal preparation) in NS. It appears that smoking reduces NK cell activity in BALF. It is conceivable that the low NK cell activity in BALF in S might contribute to increased incidence of infection and malignancy in smokers.
In order to evaluate the effects of cigarette smoking and asbestos exposure on cellular immunity, we tested a group of cigarette smokers and asbestos workers for natural killer (NK) activity in the peripheral blood. The mean NK activity in cigarette smokers was lower than in normal subjects (13.7 +/- 1.6 versus 29.0 +/- 3%; p less than 0.05). As a group, the mean NK activity for the asbestos-exposed group was also reduced compared with that of the nonsmoking control group (22.6 +/- 3.2%; p less than 0.05). When divided according to the smoking status, the asbestos workers who were nonsmokers or ex-smokers showed similar decreases in NK activity compared with normal subjects (19.5 +/- 6.2 and 21.2 +/- 4.5%, respectively; p less than 0.05). A subgroup of asbestos-exposed subjects who currently smoked showed no decrease in NK activity. The data show that NK activity is reduced in the peripheral blood of cigarette smokers and asbestos workers. The relatively normal NK activity found in asbestos workers who also smoked is unexplained. Impairment of NK activity is a potential mechanism for the increased incidence of infection and cancer in smokers and neoplasia in asbestos workers.
Natural killer (NK) cells play a central role in immune surveillance against tumors and viral infections. NK activity is depressed in patients who have a wide range of carcinomas, including carcinomas of the lung. Peripheral blood NK activity was measured in 22 nonsmokers, 15 light/moderate smokers, 12 heavy smokers, and 19 patients with carcinoma of the lung. Patients with carcinoma of the lung had marked depression in NK activity compared with nonsmokers. Light/moderate smokers had NK activity comparable to that of nonsmokers, whereas heavy smokers had marked depression in NK activity that was comparable to that of patients with carcinoma of the lung. These results suggest that smoking-induced alterations in NK activity may have a role in the pathogenesis of smoking-associated carcinoma of the lung.
In 86,488 multiphasic examinations, mean leukocyte counts were highest in cigarette smokers, intermediate in ex-cigarette and cigar or pipe smokers, and lowest in nonsmokers. Among the races, whites had the highest, yellows next, and blacks the lowest leukocyte counts. The leukocyte count was related to quantity smoked, inhalation, and smoking duration. Most groups who changed smoking habits showed corresponding changes in leukocyte counts. Higher leukocyte counts in smokers appeared largely to be a direct effect of smoking, although a small part of the increase seemed attributable to chronic bronchitis. A contribution of genetic or constitutional differences between smokers and nonsmokers was not ruled out. “Normal” leukocyte count values should take into account age, sex, race, and smoking status.
Radioimmunoassays for nicotine and one of its major metabolites, cotinine, which permit estimation of these compounds in tissue extracts and physiological fluids at the picomole level, have been developed. The specificities of the antibodies are such that quantitative determination of nicotine and cotinine in the presence of each other and in the presence of other metabolites including cotinine N-oxide, desmethylcotinine, γ-(3-pyridyl)-γ-oxo-N-methylbutyramide, γ-(3-pyridyl)-γ-oxobutyric acid, nicotine N′-oxide, and nornicotine can be made. The radioimmunoassays have been used to monitor the oxidation of nicotine to cotinine by NADPH and oxygen-dependent oxidases present in rabbit liver extracts. The results obtained in the radioimmunoassays were confirmed by isolation and quantitation of cotinine and nicotine from the enzymatic reaction mixtures by high-pressure liquid chromatography. The levels of nicotine and cotinine in sera and urine of smokers were also determined.
Human peripheral lymphocytes were stimulated to grow with phytohemagglutinin (PHA). The addition of nicotine to the cultures resulted in significantly decreased growth (DNA synthesis) of the lymphocytes. Doses ranging from 0.004 to 122 μg/ml all produced about the same amount of depression (93% of control), ie, there was no dose-response relationship. The same range of depression resulted both when nicotine was present throughout the 3-day culture period and when it was added during harvest (4 hr prior to termination of the cultures). This suggests that the effect of nicotine is on DNA synthesis, not on PHA or the process of stimulation. Cell counts at the end of the culture period were not affected by up to 24.5 μg/ml nicotine in either PHA-stimulated or unstimulated cultures. The lack of a dose-response relationship suggests that even light smoking may have an effect on cellular immunity.
The nonspecific and specific arms of the immune response are described. The nonspecific components consist of three cell types - macrophages, natural killer and killer cells - and the specific components are antibody produced by B lymphocytes and regulatory and effector T lymphocytes. The evidence suggests that a surveillance system does operate, since at least some tumours are contained. Malignant lesions are more common in unselected autopsies and surgical biopsies of noncancer patients compared with the observed rate of clinical cases; and spontaneous cures of cancer do occur. There is general agreement that surveillance of all types of tumours by the specific components of the immune response does not occur; but there is direct evidence from some model systems and correlations from the incidence and class of tumours which arise in germ-free athymic mice, in immunosuppressed patients with transplants and in immunodeficient patients that the specific immune response, particularly by effector T cells, may control the expression of some tumours of lymphoreticular cells. Such surveillance may be superimposed on a more general system which is mediated by the nonspecific elements. One possible way of increasing the efficiency of the system would be to provide some of the soluble mediators of activated effector cells such as macrophages and T cells. Thus, administration of interferon has had some success, and there is a case for further purification of these and other lymphokines and monokines for administration to patients.