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Significance of the IL-6 pathway in nasal polyposis in Chinese patients
Abstract
Background:
The interleukin-6 (IL-6) pathway is known to be important in Th17 cell differentiation and in the pathology of many inflammatory disorders. However, the significance of the IL-6 pathway in nasal polyposis (NP) in Chinese patients remains unclear.
Objective:
The aim of this study was to evaluate the functions of the IL-6 pathway in NP in Chinese patients.
Methods:
The levels of IL-6 pathway components, including IL-6, soluble IL-6 receptor (sIL-6R), phosphoSTAT3 (pSTAT3), and suppressor of cytokine signalling 3 (SOCS3), were assessed. The Th17 milieu was examined by measuring the levels of retinoid acid-related orphan receptor C (RORc) and IL-17A.
Results:
Levels of IL-6 pathway components, RORc, and IL-17A were significantly higher in both NP groups than in the control(p<0.05). Furthermore, significantly higher levels of pSTAT3, RORc, and IL-17A, and significantly lower levels of SOCS3 were found in the atopic group than in the non-atopic group(P<0.05). IL-6 and sIL-6R levels were not significantly different between the 2 NP groups(P>0.05). pSTAT3 exhibited significantly positive correlations with RORc and IL-17A(P<0.01).
Conclusions:
The expression levels of the IL-6 pathway components were significantly higher in NP patients. Moreover, p-STAT3 levels were much higher in the atopic group, and were associated with a more severe Th17 response. These results suggest that the IL-6 pathway may play a crucial role in the pathology of NP in Chinese patients, and atopy may contribute to NP by affecting the IL-6 pathway.
... Nazal polipozis nazal kavite mukozası ve paranazal sinüs mukozasında eozinofil, T hücre ve nötrofil hücrelerinin rol aldığı enflamasyon ile karakterize bir hastalıktır. [1] Sıklıkla kronik sinüzit ile beraber seyretmekle birlikte toplumda görülme oranı %1-4 arasındadır. [2] Burun tıkanıklığı, koku alma bozukluğu, burun akıntısı ve hapşırma bu hastalarda görülen başlıca şikayetlerdir. ...
... Nazal polip (NP) nazal mukoza ve paranazal mukozada eozinofil, T hücre, nötrofil ve plazma hücrelerinin görüldüğü ilerleyici enflamasyon ile karakterize bir hastalıktır. [1] Nazal polip toplumda %1-4 oranında görülür ve sıklıkla kronik rinosinüzit ile beraberdir. [2] Astım, aspirin hipersensivitesi, kistik fibrozis ve Churg-Strauss sendromu ile NP daha sık görülmektedir. ...
This study aims to investigate the correlations between nasal polyposis (NP) and NP density with neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR).
The study included 105 patients (72 males, 33 females; mean age 41.33±12.85 years; range 16 to 63 years) diagnosed as NP (NP group) and 83 healthy individuals (54 males, 29 females; mean age 44.01±8.50 years; range 18 to 62 years) (control group). Nasal polyposis density score was calculated with preoperative Lund-Mackay computed tomography grading system. Neutrophil to lymphocyte and PLR ratio values of NP and control groups were calculated and statistically compared. Neutrophil to lymphocyte and PLR values were statistically compared in terms of NP density in the NP group.
Mean NLR value was 2.26 in the NP group and 1.75 in the control group with a statistically significant difference (p=0.001). Mean PLR value was 120.79 in the NP group and 109.84 in the control group with a statistically insignificant difference (p=0.073).
Neutrophil to lymphocyte ratio value may be used as a novel marker that is easily administered in patients with nasal polyps and obtained with low-cost tests. New studies with larger patient series are needed for the value of PLR.
... IL-6, a proinflammatory cytokine, is known to be important in the pathogenesis of many inflammatory disorders, including allergic asthma. Recent studies suggest that atopy may influence the IL-6 pathways to induce a more severe Th1 response [29]. IL-10 is an anti-inflammatory cytokine that has been found to be increased in atopic asthmatics [19] and decreased in nonatopic asthma [20]. ...
Purpose:
Fractional exhaled nitric oxide (FeNO) has emerged as an important biomarker in asthma. Increasing evidence points to atopy as a confounding factor in the interpretation of elevated FeNO. We conducted a longitudinal study to understand the clinical significance of FeNO as an inflammatory biomarker.
Methods:
We identified 19 children aged 13-15 years at baseline with a significant elevation in FeNO ≥ 80 parts per billion (ppb) and randomly selected a group of children of similar age with a moderate elevation (40-79 ppb) and normal-to-low FeNO (<40 ppb). Between November 2010 and July 2011, three additional study visits were conducted.
Results:
Ninety-three children participated in the study. There were 16, 24, and 53 participants in the high, mid, and low FeNO groups. During 1.5 years of follow-up, mean FeNO levels were 82.6 ppb (standard deviation [SD] = 65.9) for atopic asthmatics, 50.6 ppb (SD = 42.6) for nonasthmatic atopics, 17.0 ppb (SD = 10.8) for nonatopic asthmatics, and 17.8 ppb (SD = 13.9) for nonatopic nonasthmatics (p < 0.001). FeNO levels remained stable: 63 % of the high FeNO group had a FeNO ≥ 80 across all 4 measurements and 87 % of the normal-to-low FeNO group had a FeNO of <40 across all 4 measurements. The high FeNO group also was found to have an elevation in IL-5 (p = 0.04), IL-6 (p = 0.003), IL-10 (p = 0.002), and total serum IgE (p < 0.001), after adjustment by age, sex, height, body mass index, and atopy and asthma status.
Conclusions:
An elevation of FeNO appears to indicate an atopic phenotype regardless of an asthma diagnosis, clinical symptoms, or corticosteroid use. An elevation of FeNO also is associated with a systemic elevation in inflammatory cytokines.
... IL-6, a pro-inflammatory cytokine, activator of transcription 3 (STAT3) leading to Th17 differentiation may involve in pathogenesis of several diseases such as RA, Crohn's disease and asthma. 6-7 Wang et al. 8 from the first Affiliated Hospital of Chongqing Medical University in China, reported in this issue using immunohistochemistry and western blot analysis showed that significantly higher numbers of pSTAT3+ cells and pSTAT3 proteins level were detected in the NP patients compared to control and non-atopic groups. When IL-6,sIL-6R, and IL-17A levels were determined by ELISA, they were all significantly higher in NP. ...
IL-17-secreting CD4(+) T cells are critically involved in inflammatory immune responses. Development of these cells is promoted in vivo and in vitro by IL-23 or TGFbeta1 plus IL-6. Despite growing interest in this inflammatory Th subset, little is known about the transcription factors that are required for their development. We demonstrate that Stat3 is required for programming the TGFbeta1 plus IL-6 and IL-23-stimulated IL-17-secreting phenotype, as well as for RORgammat expression in TGFbeta1 plus IL-6-primed cells. Moreover, retroviral transduction of a constitutively active Stat3 into differentiating T cell cultures enhances IL-17 production from these cells. We further show that Stat4 is partially required for the development of IL-23-, but not TGFbeta1 plus IL-6-primed IL-17-secreting cells, and is absolutely required for IL-17 production in response to IL-23 plus IL-18. The requirements for Stat3 and Stat4 in the development of these IL-17-secreting subsets reveal additional mechanisms in Th cell fate decisions during the generation of proinflammatory cell types.
The pro-inflammatory cytokine interleukin (IL)-6 (refs. 1-5) can bind to cells lacking the IL-6 receptor (IL-6R) when it forms a complex with the soluble IL-6R (sIL-6R) (trans signaling). Here, we have assessed the contribution of this system to the increased resistance of mucosal T cells against apoptosis in Crohn disease (CD), a chronic inflammatory disease of the gastrointestinal tract. A neutralizing antibody against IL-6R suppressed established experimental colitis in various animal models of CD mediated by type 1 T-helper cells, by inducing apoptosis of lamina propria T cells. Similarly, specific neutralization of sIL-6R in vivo by a newly designed gp130-Fc fusion protein caused suppression of colitis activity and induction of apoptosis, indicating that sIL-6R prevents mucosal T-cell apoptosis. In patients with CD, mucosal T cells showed strong evidence for IL-6 trans signaling, with activation of signal transducer and activator of transcription 3, bcl-2 and bcl-xl. Blockade of IL-6 trans signaling caused T-cell apoptosis, indicating that the IL-6-sIL-6R system mediates the resistance of T cells to apoptosis in CD. These data indicate that a pathway of T-cell activation driven by IL-6-sIL-6R contributes to the perpetuation of chronic intestinal inflammation. Specific targeting of this pathway may be a promising new approach for the treatment of CD.
IL-6 is a pleiotropic cytokine involved in the physiology of virtually every organ system. Recent studies have demonstrated that IL-6 has a very important role in regulating the balance between IL-17-producing Th17 cells and regulatory T cells (Treg). The two T-cell subsets play prominent roles in immune functions: Th17 cell is a key player in the pathogenesis of autoimmune diseases and protection against bacterial infections, while Treg functions to restrain excessive effector T-cell responses. IL-6 induces the development of Th17 cells from naïve T cells together with TGF-beta; in contrast, IL-6 inhibits TGF-beta-induced Treg differentiation. Dysregulation or overproduction of IL-6 leads to autoimmune diseases such as multiple sclerosis (MS) and rheumatoid arthritis (RA), in which Th17 cells are considered to be the primary cause of pathology. Given the critical role of IL-6 in altering the balance between Treg and Th17 cells, controlling IL-6 activities is potentially an effective approach in the treatment of various autoimmune and inflammatory diseases. Here, we review the role of IL-6 in regulating Th17/Treg balance and describe the critical functions of IL-6 and Th17 in immunity and immune-pathology.
TGF-beta, together with IL-6 and IL-21, promotes Th17 cell development. IL-6 and IL-21 induce activation of STAT3, which is crucial for Th17 cell differentiation, as well as the expression of suppressor of cytokine signaling (SOCS)3, a major negative feedback regulator of STAT3-activating cytokines that negatively regulates Th17 cells. However, it is still largely unclear how TGF-beta regulates Th17 cell development and which TGF-beta signaling pathway is involved in Th17 cell development. In this report, we demonstrate that TGF-beta inhibits IL-6- and IL-21-induced SOCS3 expression, thus enhancing as well as prolonging STAT3 activation in naive CD4(+)CD25(-) T cells. TGF-beta inhibits IL-6-induced SOCS3 promoter activity in T cells. Also, SOCS3 small interfering RNA knockdown partially compensates for the action of TGF-beta on Th17 cell development. In mice with a dominant-negative form of TGF-beta receptor II and impaired TGF-beta signaling, IL-6-induced CD4(+) T cell expression of SOCS3 is higher whereas STAT3 activation is lower compared with wild-type B6 CD4(+) T cells. The addition of a TGF-beta receptor I kinase inhibitor that blocks Smad-dependent TGF-beta signaling greatly, but not completely, abrogates the effect of TGF-beta on Th17 cell differentiation. Our data indicate that inhibition of SOCS3 and, thus, enhancement of STAT3 activation is at least one of the mechanisms of TGF-beta promotion of Th17 cell development.
Nasal polyposis is highly prevalent in the general population. Its exact origin is unknown, although several factors are involved in the etiology and development of this condition. Clinical patterns, a history of atopy, environmental exposure, eosinophil-mediated inflammation, the presence of inflammatory mediators, and sensitization to some allergens indicate that nasal polyposis is associated with allergic phenomena. The aim of this study was to identify the association between nasal polyposis and allergic factors by examining hypersensitivity reactions to common allergens and environmental exposure that could lead to the development of atopy.
We conducted a comparative study of 190 patients with nasal polyposis and 190 healthy individuals. The study included clinical and epidemiological variables, environmental exposure factors, and an allergology workup using skin prick tests with 18 inhaled allergens.
A total of 121 patients (63.7%) of the 190 were male; 62.1% had a family history of allergy. The incidence of asthma was 48.9% among the patients and only 2.3% among the controls (P < .001). The factor most frequently involved in the patients' symptoms was weather changes (67.4%). Skin prick tests were positive in 63.2% of the patients and 31.1% of the controls. The allergens that most frequently elicited a reaction from the patients in the prick tests were Dermatophagoides pteronyssinus (27.7%), Dermatophagoides farinae (21.3%), and Olea europaea (21.1%). The difference between these results and those of the controls was statistically significant.
Patients with nasal polyposis are sensitive to the most common allergens in our environment and exhibit a clear-cut correlation with other allergic factors, as confirmed by personal and family histories, the presence of chronic rhinitis, and the results of in vivo tests.
Interest in the surgical treatment of chronic rhinosinusitis has increased, primarily because rigid endoscopy and, more particularly, computed tomographic scanning have facilitated the visualization of disease. At the same time it has become both scientifically and financially imperative to audit therapeutic outcome. Consequently, a staging system for nonneoplastic sinus disease is needed. It is clear that any assessment of medical or surgical therapeutic response requires a method of quantifying disease severity that will be widely accepted by practitioners in the field. This acceptance will largely depend on how easy the method is to apply. With computed tomographic scanning it is possible to more accurately determine the extent of the pathologic condition in rhinosinusitis, a disease in which the severity of symptoms and the appearances on nasal endoscopy have a significantly more unpredictable correlation with the extent of disease. One goal of the Task Force on Rhinosinusitis of the American Academy of Otolaryngology-Head and Neck Surgery was to recommend a system for outcomes research that combines quantification with ease of application.
Nasal polyps in adults, characterized by abundant eosinophils, local overproduction of immunoglobulin E, and often associated with asthma, have been appreciated as an eosinophilic inflammation, potentially of allergic origin, but unrelated to a bacterial impact. Evidence accumulates, however, that Staphylococcus aureus colonizes chronic rhinosinusitis with, but not without polyps, with significantly increased prevalence. The germs release enterotoxins, which act as superantigens and induce a topical multiclonal IgE-formation as well as a severe, possibly steroid-insensitive eosinophilic inflammation. Recently, S. aureus could be demonstrated to reside intraepithelially, and potentially to release superantigens into the tissue from within the epithelial cells. An immune defect, either in the innate or adaptive immunity, might be responsible for this phenomenon. Follicle-like structures and lymphocyte accumulations, specifically binding enterotoxins, can be found within the polyp tissues, giving rise to local IgE formation.
The superantigen-induced immune response also leads to a modulation of the severity of the eosinophilic inflammation, and may be linked to lower airway co-morbidity in polyp patients. Interestingly, IgE antibodies to enterotoxins can be found in the majority of aspirin-sensitive polyp tissues, associated with a substantial increase in ECP and IL-5. The possible role of S. aureus enterotoxins in polyp disease in Europe, the US and Asia has meanwhile been supported by several studies, demonstrating the presence of IgE antibodies to enterotoxins and inflammatory consequences in nasal polyp tissue.
First studies also point to an involvement of S. aureus derived enterotoxins in lower airway disease, such as severe asthma and exacerbated COPD, clearly suggesting a clinical need for diagnosis and treatment of the germ and its related effects. Therapeutic approaches are so far empirical, and need further study, also serving to proof the clinical relevance of the concept.
Recent studies suggest that human regulatory T (T reg) cells protect against the development of allergic and asthmatic disease and that their function is impaired during active disease. Two new studies contribute to our understanding of the role that T reg cells play in the control of allergic airway disease in mice. However, these studies also highlight several outstanding questions in the field.
Suppressor of cytokine signaling (Socs) 3 is a cytokine-inducible inhibitor with critical but selective cell-specific effects. We show that deficiency of Socs3 in T cells had minimal effects on differentiation of T cells to the T helper (Th) 1 or Th2 subsets; accordingly, Socs3 had no effect on IL-12-dependent signal transducer and activator of transcription (Stat) 4 phosphorylation or IL-4-dependent Stat6 phosphorylation. By contrast, Socs3 was found to be a major regulator of IL-23-mediated Stat3 phosphorylation and Th17 generation, and Stat3 directly binds to the IL-17A and IL-17F promoters. We conclude that Socs3 is an essential negative regulator of IL-23 signaling, inhibition of which constrains the generation of Th17 differentiation.
• signal transducer and activator of transcription 3
• T lymphocytes
RA is an autoimmune disease characterized by sustained imbalance between pro- and antiinflammatory immune mechanisms. The SOCS proteins are negative regulators of cytokine signaling, but to date there has been little information on their function in disease. The generation of Socs3(-/Delta vav) mice, which lack SOCS-3 in the hematopoietic and endothelial cell compartment, allowed us to explore the role of endogenous SOCS-3 during acute inflammatory arthritis. Joint inflammation in Socs3(-/Delta vav) mice was particularly severe and was characterized by increased numbers of neutrophils in the inflamed synovium, bone marrow, peripheral blood, and spleen. These features were most likely due to increased production of and enhanced responsiveness to G-CSF and IL-6 during arthritis in these mice. Local osteoclast generation and bone destruction were also dramatically increased in the absence of SOCS-3, as was macrophage activation. Finally, SOCS-3 was found to negatively regulate CD4+ T lymphocyte activation, including production of the pleiotropic cytokine IL-17. The absence of SOCS-3 therefore had dramatic effects in this disease model, with a broader impact on cellular responses than SOCS-1 deficiency. These findings provide direct in vivo evidence that endogenous SOCS-3 is a critical negative regulator of multiple cell types orchestrating inflammatory joint disease.
Chronic rhinosinusitis (CRS) clinically is a heterogeneous group of sinus diseases, which may cover different disease entities, or may represent a disease continuum. Studying inflammatory cells and mediators in clearly defined disease subgroups may lead to a better differentiation of chronic sinus diseases.
Sinonasal mucosal tissue from 10 nasal polyp (NP) patients, 13 cystic fibrosis patients (CF-NP), eight CRS subjects without polyps, and nine control patients were stained for CD3, CD25, CD68, CD20, myeloperoxidase (MPO), CD138 and tissue homogenates were assayed for eotaxin, interleukin (IL)-1beta, IL-2sRalpha, IL-5, interferon (IFN)-gamma, IL-8, transforming growth factor (TGF)-beta1, tumor necrosis factor-alpha, and MPO by enzyme-linked immunosorbent assay or UNICAP system.
Nasal polyp and CF-NP showed increased numbers and activation of T cells, while only NP displayed an increase in plasma cells. Nasal polyp had significantly higher levels of eosinophilic markers [eosinophils, eotaxin, and eosinophil cationic protein (ECP)] compared with CRS, controls and CF-NP. Chronic rhinosinusitis was characterized by a Th1 polarization with high levels of IFN-gamma and TGF-beta, while NP showed a Th2 polarization with high IL-5 and immunoglobulin (Ig) E concentrations. Nasal polyp and CF-NP were discriminated by edema from CRS and controls, with CF-NP displaying a very prominent neutrophilic inflammation.
Based on cellular and mediator profiles, we suggest that CRS, NP, and CF-NP are distinct disease entities within the group of chronic sinus diseases.
Interleukin-17 (IL-17)-producing helper T (TH) cells, named as TH(IL-17), TH17, or inflammatory TH (THi), have been recently identified as a novel effector lineage. However, how cytokine signals mediate THi differentiation is unclear. We found that IL-6 functioned to up-regulate IL-23R and that IL-23 synergized with IL-6 in promoting THi generation. STAT3, activated by both IL-6 and IL-23, plays a critical role in THi development. A hyperactive form of STAT3 promoted THi development, whereas this differentiation process was greatly impaired in STAT3-deficient T cells. Moreover, STAT3 regulated the expression of retinoic acid receptor-related orphan receptor gamma-T (RORgamma t), a THi-specific transcriptional regulator; STAT3 deficiency impaired RORgamma t expression and led to elevated expression of T-box expressed in T cells (T-bet) and Forkhead box P3 (Foxp3). Our data thus demonstrate a pathway whereby cytokines regulate THi differentiation through a selective STAT transcription factor that functions to regulate lineage-specific gene expression.
There is a need for more research on all forms of rhinosinusitis. Progress in this area has been hampered by a lack of consensus definitions and the limited number of published clinical trials.Objectives
To develop consensus definitions for rhinosinusitis and outline strategies useful in clinical trials.Study designFive national societies, The American Academy of Allergy, Asthma and Immunology; The American Academy of Otolaryngic Allergy; The American Academy of Otolaryngology Head and Neck Surgery; The American College of Allergy, Asthma and Immunology; and the American Rhinologic Society formed an expert panel from multiple disciplines. Over two days, the panel developed definitions for rhinosinusitis and outlined strategies for design of clinical trials.ResultsCommittee members agreed to adopt the term “rhinosinusitis” and reached consensus on definitions and strategies for clinical research on acute presumed bacterial rhinosinusitis, chronic rhinosinusitis without polyposis, chronic rhinosinusitis with polyposis, and classic allergic fungal rhinosinusitis. Symptom and objective criteria, measures for monitoring research progress, and use of symptom scoring tools, quality-of-life instruments, radiologic studies, and rhinoscopic assessment were outlined for each condition.Conclusions
The recommendations from this conference should improve accuracy of clinical diagnosis and serve as a starting point for design of rhinosinusitis clinical trials.
Interleukin-17A (IL-17A) is a key inflammatory cytokine in many disorders, while the significance of IL-17A in nasal polyposis (NP) is still obscure. This study aimed to investigate the expression of IL-17A in nasal polyps from both atopic and nonatopic patients and its associations with clinical and histological features.
In all, 30 patients with NP were included, and were grouped into atopic and nonatopic patients according to skin prick test (SPT). Disease severity was evaluated by symptom score, endoscopy score and CT score. Histological characteristics were assessed by eosinophilic infiltration, basement membrane (BM) thickness, epithelial damage, squamous metaplasia, and goblet cell hyperplasia. IL-17A expression in polyps was detected by ELISA and immunohistochemistry.
Endoscopy score and CT score were significantly higher in atopic NP patients than in nonatopic NP patients (p < 0.05). IL-17A levels were significantly upregulated in both atopic (p < 0.01) and nonatopic (p < 0.05) patients versus controls. Furthermore, IL-17A levels were significantly higher in the atopic group versus nonatopic group. Significantly positive correlations were found between IL-17A levels and CT scores, eosinophilic infiltration and BM thicknesses.
These results indicated that expression of IL-17A was significantly upregulated in NP patients and was more severe in atopic NP patients, suggesting that IL-17A may play an important role in the pathology of NP and atopy may contribute to NP by stimulating the production of IL-17A.
Nasal polyposis (NP) is a chronic inflammatory disease of the nasal cavity and sinuses that is regulated by T lymphocyte subsets. Imbalance of Th17/Treg has been considered critical in the development of inflammation and atopic reactions. To assess whether the balance of Th17/Treg is disrupted in patients with NP, we evaluated the distribution of Th17 and Treg cells among peripheral blood mononuclear cells (PBMCs) in atopic patients with NP, non-atopic patients with NP and controls. We then determined mRNA levels of RORc and Foxp3 and protein levels of IL-17, TGF-β and IL-10 in polyp tissue among the three groups. Finally, we investigated the correlation between Th17-, Treg- and Th1-, Th2-related cytokines (INF-γ, IL-4, IL-5). The results demonstrated that both atopic and non-atopic patients with NP revealed significantly increased Th17 proportion and decreased Treg proportion in PBMCs, as well as significantly increased RORc and IL-17 levels and decreased Foxp3 and TGF-β levels in polyp tissue. Furthermore, these differences were significant between atopic and non-atopic groups. The frequency of Treg in PBMCs was found to be negatively correlated with Th1 and Th2 cytokines in polyps. These results indicated that an impaired balance of Th17/Treg existed in patients with NP and was more severe in atopic patients, suggesting that the imbalance of Treg/Th17 may play an important role in the development of NP and that atopy may aggravate NP by promoting the imbalance of Th17/Treg.
STAT3, an essential transcription factor with pleiotropic functions, plays critical roles in the pathogenesis of autoimmunity. Despite recent data linking STAT3 with inflammatory bowel disease, exactly how it contributes to chronic intestinal inflammation is not known. Using a T cell transfer model of colitis, we found that STAT3 expression in T cells was essential for the induction of both colitis and systemic inflammation. STAT3 was critical in modulating the balance of T helper 17 (Th17) and regulatory T (Treg) cells, as well as in promoting CD4(+) T cell proliferation. We used chromatin immunoprecipitation and massive parallel sequencing (ChIP-Seq) to define the genome-wide targets of STAT3 in CD4(+) T cells. We found that STAT3 bound to multiple genes involved in Th17 cell differentiation, cell activation, proliferation, and survival, regulating both expression and epigenetic modifications. Thus, STAT3 orchestrates multiple critical aspects of T cell function in inflammation and homeostasis.
IL-6 activates T(H)17 cells and regulates the response of B lymphocytes and regulatory T cells. The IL-6 receptor and the membrane protein, glycoprotein 130 (gp130), form an active signaling complex that signals through signal transducer and activator of transcription 3 (STAT3) and other signaling molecules. Both the IL-6 receptor (IL-6R) and gp130 can be found in soluble forms that regulate the pathway.
We measured IL-6 signaling components and IL-17 in chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP), CRS without nasal polyps (CRSsNP), and controls to assess the IL-6 pathway in CRS.
IL-6, soluble IL-6R, soluble gp130 (sgp130), and IL-17 were measured in sinus tissue extracts and in nasal lavage fluid by either cytokine bead array or ELISA. phosphoSTAT3 (p-STAT3) was determined by Western blot and by immunohistochemistry.
IL-6 protein was significantly (P < .001) increased in CRSwNP compared with CRSsNP and controls. Soluble IL-6R was also increased in nasal polyp compared with control tissue (P < .01). Despite elevated IL-6 and sIL-6R, IL-17A, E, and F were undetectable in the sinus tissue from most of the patients with CRS and controls. p-STAT3 levels were reduced in the polyp tissue, possibly indicating reduced activity of IL-6 in the tissue. sgp130 was elevated in CRSwNP compared with CRSsNP and controls.
p-STAT3 levels are decreased in CRSwNP despite increased levels of IL-6 and sIL-6R and are associated with the absence of an IL-17 response. This may be a response to elevated levels of sgp130, a known inhibitor of IL-6 signaling. These results indicate that IL-6 and its signaling pathway may be altered in CRSwNP.
Chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP) is reported to be different in inflammatory patterns of the sinonasal mucosa in white patients. Studies in nonwhite populations may further be helpful to understand the pathogenic mechanisms of CRS.
To investigate the immunopathologic profiles of CRSwNP and CRSsNP in adult Chinese.
Histologic characteristics of surgical samples were analyzed in 50 controls, 94 CRSsNP patients, and 151 CRSwNP patients. Tissue samples from 17 controls, 36 CRSsNP patients, and 45 CRSwNP patients were stained for CD3, CD4, CD8, CD20, CD68, myeloperoxidase, and dendritic cell lysosome-associated membrane protein. Expression profiles of transcription factors of T-cell subsets in relation to cytokines and a marker of natural killer T cell (Valpha24) were examined by means of quantitative RT-PCR.
Over half of CRSwNP patients presented noneosinophilic inflammation. CRSwNP had a higher number of eosinophils, plasma cells, and CD3(+), CD8(+), CD20(+), and CD68(+) cells and a lower myeloperoxidase expression rate than CRSsNP. Expression levels of transcription factors and cytokines of T(H)1/T(H)2/T(H)17 were increased, whereas the expression rate of Forkhead box p3 and TGF-beta1 was decreased in both CRSsNP and CRSwNP compared with controls. Comparing CRSsNP and CRSwNP, CRSsNP had higher levels of IFN-gamma expression, whereas only eosinophilic CRSwNP demonstrated an enhanced expression of GATA-3 and IL-5. Compared with noneosinophilic CRSwNP, an exaggerated T(H)2/T(H)17 reaction and Valpha24 expression were found in eosinophilic CRSwNP.
Both Chinese CRSsNP and CRSwNP patients demonstrate impaired regulatory T cell function and enhanced T(H)1/T(H)2/T(H)17 responses. CRSsNP is confirmed to be a predominant T(H)1 milieu, whereas T(H)2 skewed inflammation with predominant T(H)17 reactions, and infiltration of natural killer T cells can be demonstrated only in eosinophilic CRSwNP, but not in noneosinophilic CRSwNP.
Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by the accumulation of inflammatory cells; however, an eosinophil predominance is seen in white (Belgian), but not Asian (south Chinese), patients with polyps.
We sought to investigate the association of inflammatory cell predominance with regulatory T-cell and T-effector cell patterns.
Nasal mucosal tissue was obtained from 26 consecutive Belgian patients with CRSwNP and 21 Belgian control subjects and 29 south Chinese patients with CRSwNP and 29 south Chinese control subjects, who all underwent phenotyping, including nasal endoscopy and computed tomographic scanning. Tissues were investigated for granulocytes and their products and T-effector/regulatory T cells and related cytokines.
Both CRSwNP groups were comparable in terms of symptoms, computed tomographic scan results, and nasal endoscopy results, but asthma comorbidity was significantly higher in white patients. Tissue from white patients with CRSwNP was characterized by eosinophilic inflammation (eosinophil cationic protein/myeloperoxidase ratio > 2), whereas samples from Asian patients were biased toward neutrophilic inflammation (eosinophil cationic protein/myeloperoxidase ratio = 0.25). Both CRSwNP groups demonstrated significant upregulation of the T-cell activation marker soluble IL-2 receptor alpha and significant downregulation of Foxp3 expression and TGF-beta1 protein content versus their respective control groups. However, whereas white patients displayed a significant increase in T(H)2 cytokine and related marker levels versus control subjects and versus Asian patients, the latter showed a T(H)1/T(H)17 cell pattern versus control tissue.
Nasal polyps (CRSwNP) from white and Asian patients are both characterized by T-cell activation and impaired regulatory T-cell function; however, T-effector cells in the samples from white patients were T(H)2-biased, whereas samples from their Asian counterparts demonstrated a T(H)1/T(H)17 polarization.
T cell development and differentiation is carefully orchestrated by a series of cytokines. The importance of STAT family proteins in mediating signals by these cytokines is well-known, but new information on the role of STATs in novel aspects of T cell function and T cell subsets continues to accumulate. Recent studies have placed Stat5a/b and Stat3 center stage in T cell development and differentiation. Stat5a/b are indispensable in T regulatory (Treg) cell development and maintenance, and negatively regulate T helper 17 (Th17) cell differentiation. Conversely, Stat3 is essential for Th17 differentiation and inhibits Treg cells. The balance of Treg and Th17 cells is thought to be critical in maintaining immune tolerance, while preserving effective host defense. Therefore, Stat5a/b and Stat3 are emerging to be key players in T cell differentiation and homeostasis.
Rhinosinusitis is a significant and increasing health problem which results in a large financial burden on society. This evidence based position paper describes what is known about rhinosinusitis and nasal polyps, offers evidence based recommendations on diagnosis and treatment, and considers how we can make progress with research in this area. Rhinitis and sinusitis usually coexist and are concurrent in most individuals; thus, the correct terminology is now rhinosinusitis. Rhinosinusitis (including nasal polyps) is defined as inflammation of the nose and the paranasal sinuses characterised by two or more symptoms, one of which should be either nasal blockage/obstruction/congestion or nasal discharge (anterior/posterior nasal drip), facial pain/pressure, +/- reduction or loss of smell; and either endoscopic signs of polyps and/or mucopurulent discharge primarily from middle meatus and/or; oedema/mucosal obstruction primarily in middle meatus, and/or CT changes showing mucosal changes within the ostiomeatal complex and/or sinuses. The paper gives different definitions for epidemiology, first line and second line treatment and for research. Furthermore the paper describes the anatomy and (patho)physiology, epidemiology and predisposing factors, inflammatory mechanisms, evidence based diagnosis, medical and surgical treatment in acute and chronic rhinosinusitis and nasal polyposis in adults and children. Evidence based schemes for diagnosis and treatment are given for the first and second line clinicians. Moreover attention is given to complications and socio-economic cost of chronic rhinosinusitis and nasal polyps. Last but not least the relation to the lower airways is discussed.
Considerable clinical success has been claimed for functional endoscopic sinus surgery but objective assessment of prospective series is lacking in the literature. Twenty-four patients with chronic rhino-sinusitis underwent assessment of symptoms by visual analogue scoring, nasomucociliary function by ciliary beat frequency, olfaction by qualitative olfactometry and nasal airway resistance by anterior rhinomanometry pre- and post-operatively. This demonstrated a significant improvement in all symptoms examined and in ciliary beat frequency. Quantitative olfaction and anterior rhinomanometry were not improved despite diminished symptoms. These results offer quantitative evidence of clinical improvement following functional endoscopic sinus surgery which supports the pathophysiological concepts on which the technique is based.
High levels of interleukin 6 (IL 6/B cell stimulatory factor-2) were detected in synovial fluids from the joints of patients with active rheumatoid arthritis (RA). The cells found in freshly isolated synovial fluid constitutively expressed IL 6 mRNA. The synovial tissues obtained by joint biopsy were also found to produce IL 6 in vitro. Immunohistochemical analysis demonstrated that CD2+ T cells as well as CD20+ blastoid B cells in the synovial tissues produce IL 6. The data indicate that IL 6 is generated constitutively in RA and its overproduction may explain the local as well as the generalized symptoms of RA, since IL 6 can function as B cell growth and differentiation factor as well as hepatocyte-stimulating factor.
The origin of the Toll-like family of receptors pre-dates the evolutionary split between the plant and animal kingdoms. These receptors are remarkably conserved across the taxonomic kingdoms and have fundamental roles in triggering immune responses. How they trigger such responses, and how these mechanisms arose in evolution, is a topic of extensive debate. We postulate a surveillance model: these receptors "keep watch" for both endogenous and exogenous molecules that indicate tissue inquiry, infection and remodeling. Furthermore, we suggest that the first Toll-like family receptors that arose in evolution might have acted in both development and immunity by recognizing the degradation of endogenous macromolecules.
Most studies on outcome after endoscopic sinus surgery (ESS) include patients with varying degrees of disease severity. Recurrence rates cited by those studies may not apply to the subset of patients with severe polyposis. Our aim is to provide reference information for recurrence rates and need for revision surgery in patients with severe disease.
Review of patients with severe polyposis with a minimum Lund-McKay score of 16 and with a Kennedy computed tomography stage 3 or 4. Data collection included demographics, presence of asthma or documented allergy, history of previous surgery, extent of surgery, preoperative and postoperative management, recurrence rates, revision surgery rates, and follow-up.
One hundred and eighteen records were reviewed. Fifty-nine (50%) patients had asthma, and 93 (79%) had documented allergy. All patients required extensive bilateral nasal polypectomy, complete anterior and posterior ethmoidectomy, and maxillary sinusotomy. One hundred (85%) also had frontal or sphenoid sinusotomy. Follow-up ranged from 12 to 168 (median 40) months. Seventy-one (60%) developed recurrent polyposis. Fifty-five (47%) were advised to undergo revision surgery, and 32 (27%) underwent surgery. History of previous sinus surgery or asthma predicted higher recurrence (P <.005, P <.001) and revision surgery rates (P =.02, P <.001). History of allergy also predicted recurrence and need for revision (P <.001, P <.001).
Recurrence rates after ESS for severe polyposis are significant. In our study, patients with asthma are at higher risk of recurrence.
The aim of this study was to determine whether atopy influences either clinical and radiological severity or surgical revision rates in patients with chronic rhinosinusitis (CRS).
Patients who had been scheduled for endoscopic sinus surgery were classified as having CRS or nasal polyposis. Their atopic status was determined by ImmunoCAP testing. Disease severity was assessed clinically by the Lund symptom and Sino-Nasal Outcome Test 20 (SNOT-20) quality-of-life scores and radiologically by the Lund-Mackay CT score.
One hundred ninety-three consecutive patients with rhinosinusitis were included in the study. The prevalence of atopy in this group was found to be 30%. No association was found between atopic status and Lund symptom scores. Analysis of the SNOT-20 scores indicated that atopic patients had higher sneezing scores (p < 0.03), reduced productivity (p < 0.01), and reduced concentration (p < 0.01). The mean CT score was significantly higher in the atopic patients than in nonatopic patients overall (14.2+/-1.6 versus 12.2+/-1.3; p = 0.05), although within each of the clinical subgroups no statistically significant relationship was observed between a patients' atopic status and their CT scores. The rate of revision surgery was not significantly different between atopic and nonatopic patients.
These results suggest that atopic status has minimal impact on the severity of CRS.
The mechanisms by which corticosteroids reduce airway inflammation are not completely understood. Traditionally, corticosteroids were thought to inhibit cytokines exclusively at the transcriptional level. Our recent evidence, obtained in airway smooth muscle (ASM), no longer supports this view. We have found that corticosteroids do not act at the transcriptional level to reduce TNF-alpha-induced IL-6 gene expression. Rather, corticosteroids inhibit TNF-alpha-induced IL-6 secretion by reducing the stability of the IL-6 mRNA transcript. TNF-alpha-induced IL-6 mRNA decays at a significantly faster rate in ASM cells pretreated with the corticosteroid dexamethasone (t(1/2) = 2.4 h), compared to vehicle (t(1/2) = 9.0 h; P < 0.05) (results are expressed as decay constants [k] [mean +/- SEM] and half-life [h]). Interestingly, the underlying mechanism of inhibition by corticosteroids is via the up-regulation of an endogenous mitogen-activated protein kinase (MAPK) inhibitor, MAPK phosphatase-1 (MKP-1). Corticosteroids rapidly up-regulate MKP-1 in a time-dependent manner (44.6 +/- 10.5-fold increase after 24 h treatment with dexamethasone; P < 0.05), and MKP-1 up-regulation was temporally related to the inhibition of TNF-alpha-induced p38 MAPK phosphorylation. Moreover, TNF-alpha acts via a p38 MAPK-dependent pathway to stabilize the IL-6 mRNA transcript (TNF-alpha, t(1/2) = 9.6 h; SB203580 + TNF-alpha, t(1/2) = 1.5 h), exogenous expression of MKP-1 significantly inhibits TNF-alpha-induced IL-6 secretion and MKP-1 siRNA reverses the inhibition of TNF-alpha-induced IL-6 secretion by dexamethasone. Taken together, these results suggest that corticosteroid-induced MKP-1 contributes to the repression of IL-6 secretion in ASM cells.
Selective regulatory function of Socs3 in the formation of IL-17-secreting T cells
- Z Chen
- A Laurence
- Y Kanno
- M Pacher-Zavisin
- Bm Zhu
- O Shea
Chen Z, Laurence A, Kanno Y, Pacher-Zavisin M, Zhu BM,
O'Shea JJ, et al. Selective regulatory function of Socs3 in the
formation of IL-17-secreting T cells. Proc Natl Acad Sci U S A.
2006;103:8137-42.