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T Kuparinen,
I Seppälä,
J Jylhävä,
S Marttila, J Aittoniemi,
J Kettunen,
J Viikari,
M Kähönen,
O Raitakari,
T Lehtimäki,
M Hurme
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ABSTRACT: Cytomegalovirus (CMV) causes an infection, which is followed by a lifelong latency. CMV has received much attention in clinical studies, but little is known about the genetic basis of this common infection. To identify genetic polymorphisms associated with the susceptibility to and strength of anti-CMV immunoglobulin G (IgG) response to CMV infection, we conducted a genome-wide association study (GWAS) using an Illumina BeadChip containing 670 000 probes and participants from the Cardiovascular Risk in Young Finns Study, including 1486 anti-CMV IgG seropositive and 648 seronegative individuals. Statistical analyses were performed using logistic (for susceptibility) and linear regression (for strength of antibody response). None of single-nucleotide polymorphisms (SNPs) was found to be associated with susceptibility to CMV infection at the level of genome-wide significance (P<5 × 10(-8)). Also, none of the association signals identified reached genome-wide levels of statistical significance in the study of the strength of the antibody response to CMV although five SNPs in AGBL1 gene region displayed a suggestive association (lowest P-value=1.86 × 10(-6)). The results indicate that there is no strong evidence of major host genetic factors involved in either susceptibility to or the strength of antibody response to human CMV infection.
Genes and immunity 02/2012; 13(2):184-90. · 4.22 Impact Factor
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A Haarala,
M Kähönen,
T Lehtimäki, J Aittoniemi,
J Jylhävä,
N Hutri-Kähönen,
L Taittonen,
T Laitinen,
M Juonala,
J Viikari,
O T Raitakari,
M Hurme
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ABSTRACT: Human cytomegalovirus (CMV) infection is associated with a higher risk of cardiovascular disease in immunocompromised organ transplant patients. It has been linked with the pathogenesis of elevated arterial blood pressure. However, controversy exists as to whether CMV infection is associated with endothelial function, and little is known about its role as a potential risk factor for early atherosclerosis development at a young age. We aimed to discover if CMV antibody titres are associated with early vascular changes (carotid intima-media thickness, carotid artery distensibility and brachial artery flow-mediated dilation), blood pressure elevation or other traditional cardiovascular risk factors. CMV antibody titres were measured in 1074 women and 857 men (aged 24-39 years) taking part in the Cardiovascular Risk in Young Finns study. CMV antibody titres were significantly higher in women compared to men. In men, high CMV antibody titres were associated directly with age (P < 0·001) and systolic (P = 0·053) and diastolic (P = 0·002) blood pressure elevation, and associated inversely with flow-mediated dilation (P = 0·014). In women, CMV antibody titres did not associate with any of the analysed parameters. In a multivariate regression model, which included traditional atherosclerotic risk factors, CMV antibody titres were independent determinants for systolic (P = 0·029) and diastolic (P = 0·004) blood pressure elevation and flow-mediated dilation (P = 0·014) in men. High CMV antibody titres are associated independently with blood pressure and brachial artery flow-mediated dilation in young men. This association supports the hypothesis that common CMV infection and/or an immune response to CMV may lead to impaired vascular function at a young age.
Clinical & Experimental Immunology 02/2012; 167(2):309-16. · 3.36 Impact Factor
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ABSTRACT: Mannose-binding lectin (MBL) insufficiency caused by point mutations in the MBL2 gene has been associated with increased susceptibility to bacteraemic infections. We here investigated the effect of MBL2 polymorphisms on the susceptibility and clinical course of bacteraemia. The study cohort comprised 145 patients with bacteraemia and 400 controls. In the case of patients with bacteraemia, laboratory findings and clinical data were registered on admission and during six consecutive days. MBL2 structural polymorphisms at codons 52 (CGT-->TGT; designated D or O), 54 (GGC-->GAC; B or O) and 57 (GGA-->GAA; C or O) in exon 1 of the MBL2 gene and promoter region polymorphisms at position -221 (G-->C, designated Y or X alleles) were determined. No difference in MBL2 genotype frequencies between the bacteraemic patients and controls was detected, and MBL2 genotype had no independent effect on mortality, nor disease severity. However, smoking proved a significant risk factor for Gram-positive (Staphylococcus aureus, Streptococcus pneumoniae or beta-haemolytic streptococci) bacteraemia in patients carrying the variant O allele (53% current smokers in Gram-positive bacteraemia patients compared with only 21% in controls, odds ratios 4.2, 95% confidence intervals 2.0-9.0; P < 0.001), while it did not have an effect in those homozygous for the A allele. The same effect was not detected in Escherichia coli bacteraemia. In conclusion, MBL2 genotypes representing MBL insufficiency were not associated with the overall risk of bacteraemia or disease severity, but smoking in carriers of the structural variant O allele may have a deleterious effect increasing the risk of Gram-positive bacteraemia.
Scandinavian Journal of Immunology 10/2008; 68(4):438-44. · 2.23 Impact Factor
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ABSTRACT: Mannose-binding lectin (MBL) is a key mediator of innate immunity, the insufficiency of which is caused by point mutations in the MBL2 gene. MBL insufficiency is associated with increased susceptibility to infections and certain autoimmune diseases, but its impact in the pathogenesis and risk of type 1 diabetes (T1D) is controversial. We investigated the significance of the MBL2 genotype on the risk of T1D in a Finnish study population comprising 470 diabetic children and 501 controls. Furthermore, the effect of MBL2 gene polymorphism on the emergence of beta-cell autoantibodies in 289 unaffected children with human leukocyte antigen-conferred susceptibility to T1D was assessed. MBL genotype had no significant effect on the risk or onset age of T1D. However, children with the biallelic variant genotype reflecting total MBL deficiency tested positive more frequently for > or =3 autoantibodies compared with children with another genotype (odds ratio = 6.0, 95% confidence interval 1.3-28; p = 0.013). In conclusion, the MBL2 genotype did not affect susceptibility to T1D in children, and this finding does not support previous reports implicating a role of the MBL2 genotype as a factor predisposing to T1D. The association of the biallelic variant genotype with positivity for multiple autoantibodies suggests that intermolecular epitope spreading may be linked with impaired clearance of autoantigens as a result of MBL deficiency.
Human Immunology 03/2008; 69(2):108-11. · 2.84 Impact Factor
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ABSTRACT: The aim of this study was to investigate whether polymorphism of the mannose-binding lectin 2 (MBL2) gene is related to the occurrence of systemic AA amyloidosis in patients with rheumatoid arthritis (RA).
MBL2 structural gene polymorphisms at codon 52 (CGT-->TGT, Arg-->Cys; D), codon 54 (GGC-->GAC, Gly-->Asp; B) and codon 57 (GGA-->GAA, Gly--> Glu; C), and MBL2 promoter region polymorphism at position -221 (G-->C) were examined in 57 patients with RA complicated by biopsy-proven reactive amyloidosis and 51 control RA patients without amyloid.
A strong association was found between the presence of a structural MBL2 gene variant O (B, D or C) and the occurrence of amyloidosis in RA patients: 29 of 57 (50.9%) of the RA patients with amyloid had a variant allele compared with 12 of 51 (23.5%) of the RA patients without amyloid (OR 3.37, 95% CI 1.47-7.72; P = 0.004).
We conclude that variant MBL2 structural genotype constitutes a significant risk factor for reactive amyloidosis in RA and that the increased risk is probably related to MBL-mediated impairment of mononuclear phagocyte function.
Journal of Internal Medicine 10/2007; 262(4):466-9. · 5.48 Impact Factor
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T Seiskari,
A Kondrashova,
H Viskari,
M Kaila,
A-M Haapala, J Aittoniemi,
M Virta,
M Hurme,
R Uibo,
M Knip,
H Hyöty
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ABSTRACT: Epidemiological data have indicated that some infections are associated with a low risk of allergic diseases, thus supporting the idea (hygiene hypothesis) that the microbial load is an important environmental factor conferring protection against the development of allergies. We set out to test the hygiene hypothesis in a unique epidemiological setting in two socio-economically and culturally markedly different, although genetically related, populations living in geographically adjacent areas. The study cohorts included 266 schoolchildren from the Karelian Republic in Russia and 266 schoolchildren from Finland. The levels of total IgE and allergen-specific IgE for birch, cat and egg albumen were measured. Microbial antibodies were analysed against enteroviruses (coxsackievirus B4), hepatitis A virus, Helicobacter pylori and Toxoplasma gondii. Although total IgE level was higher in Russian Karelian children compared to their Finnish peers, the prevalence of allergen-specific IgE was lower among Russian Karelian children. The prevalence of microbial antibodies was, in turn, significantly more frequent in the Karelian children, reflecting the conspicuous difference in socio-economic background factors. Microbial infections were associated with lower risk of allergic sensitization in Russian Karelian children, enterovirus showing the strongest protective effect in a multivariate model. The present findings support the idea that exposure to certain infections, particularly in childhood, may protect from the development of atopy. Enterovirus infections represent a new candidate to the list of markers of such a protective environment. However, possible causal relationship needs to be confirmed in further studies.
Clinical & Experimental Immunology 05/2007; 148(1):47-52. · 3.36 Impact Factor
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ABSTRACT: The primary results after coronary artery bypass grafting are good, but early clinical events as a result of graft occlusion are still a problem. Early occlusions are thought to be due to thrombosis or fibrointimal hyperplasia superimposed by thrombosis, but the etiology of these phenomena is not fully understood. Matrix metalloproteinase-9 has been suggested to have a role in graft occlusion ex vivo.
We investigated whether the level of serum matrix metalloproteinase-9 reflects its proposed role in occlusion of vein grafts. The study population consisted of 30 men with a history of myocardial infarction and 31 men without myocardial infarction who had undergone coronary artery bypass grafting. All the men were asymptomatic.
Among the patients with no previous myocardial infarction, serum matrix metalloproteinase-9 level was significantly higher in those with graft occlusion than in those without occlusion (54.0+/-11.0 microg/L and 41.7+/-10.4 microg/L, respectively, p = 0.006), and it correlated positively with the number of occluded grafts (R = 0.55, p = 0.001). In the patients with myocardial infarction, this effect was not detected.
Serum matrix metalloproteinase-9 reflected the occurrence of vein graft occlusion in subjects with no previous history of myocardial infarction.
Scandinavian Journal of Clinical and Laboratory Investigation 02/2006; 66(1):7-14. · 1.38 Impact Factor
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ABSTRACT: Mannose-binding lectin (MBL) insufficiency due to polymorphisms in the MBL2 gene causes an opsonization defect, which has been connected to infections and atopy. We investigated the significance of MBL2 genotypes with regard to persistent asthma and atopy among adults. The genotypes were determined in 243 adults with persistent asthma and 400 controls. Atopy was determined by skin-prick test. As a result, the carriage of -221 base pairs (bp) promoter region variant allele X (nucleotide change G-->C; alleles Y-->X, respectively) causing low MBL expression proved to be a significant risk factor for asthma in non-atopic males [odds ratio (OR) = 2.52, 95% confidence interval (CI) = 1.23-5.15; P = 0.01]. Furthermore, the X-allele carriage was associated with the decrease in lung function (forced expiratory volume at 1 s, FEV(1)) during follow-up in the patients with asthma (P = 0.033), the effect being strongest for non-atopic asthmatics (P = 0.042). The MBL2 genotype had no clear effect on the occurrence of atopy in adults. In conclusion, our results abrogate the previously suggested predisposing effect of MBL insufficiency on atopy at least in adults. However, as MBL is a complement component participating in immune defence against microbes, and as in the pathogenesis of non-atopic asthma infectious agents are probably involved, the gene-environment interactions between MBL and infections should be assessed further with regard to asthma.
Clinical & Experimental Immunology 10/2005; 142(1):120-4. · 3.36 Impact Factor
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The American Journal of Gastroenterology 01/2004; 98(12):2808-9. · 7.28 Impact Factor
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ABSTRACT: To investigate the significance or mannan-binding lectin (MBL) gene alleles in patients with primary Sjogren's syndrome (pSS). Genotypes were determined in 65 pSS patients and 138 controls.
No difference in MBL genotype or allele frequencies was detected between the pSS patients and controls. However, when the effect of MBL genotypes on the diagnostic findings in pSS patients was assessed, none of the eight patients with 52/w genotype fulfilled four (definite) Californian criteria (P = 0.007). Among these eight the Chisholm-Mason histological grade was > or = 3 in only three (P = 0.017). Furthermore, the MBL concentration was lower in patients with 52/w genotype compared to those with wild-type (w/w) genotype (P = 0.035).
Our findings suggest that MBL structural gene polymorphisms do not influence on susceptibility to pSS. However, MBL may be associated with salivary gland destruction in pSS, and its concentration may be comparable with the intensity of inflammatory reaction. Further studies are warranted to clarify the possible mechanisms involved.
Scandinavian Journal of Rheumatology 02/2002; 31(6):362-5. · 2.47 Impact Factor
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ABSTRACT: We investigated responses to vaccination against pneumococcal polysaccharide, Haemophilus influenzae b (Hib) conjugate and tetanus toxoid antigens in 31 patients with chronic lymphocytic leukaemia (CLL) and 25 controls. While in the control group all antibody responses against different antigens were highly significant, in the patient group clear evidence for responsiveness was detected only in the case of Hib polysaccharide antigen. Certain CLL patient subgroups showed low reactivity against tetanus toxoid antigen. In conclusion, plain polysaccharide vaccines seem to be ineffective in patients with CLL. Conjugate vaccines, in turn, are immunogenic and may offer protection against infections caused by encapsulated bacteria in these patients. Further studies concerning an optimal vaccination scheme and clinical efficiency are warranted.
British Journal of Haematology 08/2001; 114(1):107-10. · 4.94 Impact Factor
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ABSTRACT: The use of fecal alpha1-antitrypsin in the monitoring of intestinal inflammation in infants with atopic eczema and food allergy was evaluated.
The study material comprised 26 atopic infants with confirmed food allergy. Fecal samples were collected before an elimination diet and 3 months later for the determination of alpha1-antitrypsin.
Nine (35%) of the 26 patients demonstrated an increased fecal concentration of alpha1-antitrypsin (median 3 mg/g; range 2.8-6.4 mg/g). In all nine patients (100%) the oral cow's milk challenge was positive as opposed to only six (35%) in those with normal alpha1-antitrypsin concentration (P = 0.0024). No further connections between alpha1-antitrypsin and other food allergies were detected. As a result of an adequate elimination diet, the fecal concentration of alpha1-antitrypsin was normalized in seven patients, with a favourable clinical response in atopic eczema in six and no improvement in one patient.
Our results indicate that serial determinations of fecal alpha1-antitrypsin provide a useful non-invasive tool for the detection and follow-up of intestinal inflammation in a certain group of atopic infants with cow's milk allergy and severe inflammation of the gut.
Clinical & Experimental Allergy 05/2001; 31(4):590-2. · 5.03 Impact Factor
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ABSTRACT: Group II phospholipase A2 (PLA2-II), procalcitonin (PCT) and C-reactive protein (CRP) are useful indicators of the severity of inflammation in various infections. To compare their discriminatory abilities at an early phase of bacteremia, PLA2-II, PCT and CRP were measured upon admission and 24-48 h thereafter in 29 patients with bacteremia, non-bacteremic bacterial or viral infections. The levels of PLA2-II and PCT were higher in bacteremia than in non-bacteremic bacterial or viral infections. PCT was highest upon admission, PLA2-II peaked at 12-24h, whereas CRP peaked one day later. At < or =24h, the AUC(ROC)s of PLA2-II and PCT were superior to those of CRP. Thereafter, the AUC(ROC)s of PLA2-II and PCT decreased and those of CRP increased. PLA2-II at cut-off level of 150 microg/L and PCT at 2-6 microg/L showed high sensitivity and specificity for bacteremia within the first 24h. In conclusion, PLA2-II and PCT are useful markers for early diagnosis of bacteremia. Devising analytical methods suitable for point-of-care testing would further enhance the clinical utility of the measurement of serum PLA2-II and PCT.
Scandinavian Journal of Clinical and Laboratory Investigation 02/2001; 61(7):523-30. · 1.38 Impact Factor
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ABSTRACT: We investigated the influence of plasma concentrations of immunoglobulin G (IgG), IgA, IgM, IgG subclasses and mannan-binding lectin (MBL) on susceptibility to infection in patients with chronic lymphocytic leukemia (CLL). Of 28 patients with CLL, increased susceptibility to infection was recorded in nine. Four of them (44%) had hypogammaglobulinemia as opposed to only one (5%) of the 19 patients without increased susceptibility to infection (OR 14.4; 95% CI, 1.6-130). When the effect of IgG subclasses contributing to hypogammaglobulinemia was studied, only the decreased concentrations of IgG4 and IgG2 were associated with increased susceptibility to infection. They, in turn, were intercorrelated and also highly correlated with the concentration of IgA. In fact, when these parameters were studied by a multivariable model, only the decreased concentration of IgA was shown as an independent risk factor for infection (P = 0.03). The mean concentration of MBL was significantly higher in patients with infections than in those without (6.54 mg/l and 2.75 mg/l, respectively; P = 0.001). The monitoring of its concentrations might be useful in the follow-up of infectious morbidity in CLL.
Leukemia and Lymphoma 08/1999; 34(3-4):381-5. · 2.58 Impact Factor
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ABSTRACT: The aim of this study was to investigate the significance of IgG subclasses and MBL for susceptibility to infection in association with IgA deficiency. The study population consisted of 139 apparently healthy adult blood donors with IgA deficiency and normal serum levels of IgG and IgM, and an increased susceptibility to infection demonstrated at a population level. Additionally, 216 controls matched for age and sex were investigated. IgG4 deficiency was more common and the mean level of IgG4 lower in persons with IgA deficiency than in the controls. No significant associations could be demonstrated between overt IgG subclass deficiencies and increased susceptibility to infection. However, when the mean concentrations of IgG subclasses were analysed with regard to medical history, that of IgG1 was lower in persons who reported recurrent viral respiratory infections, that of IgG3 in persons who had episodes of severe infection in their history, and that of IgG4 in persons who had recurrent mild respiratory infections, compared with those who had no particular history of infections. In contrast, MBL deficiency-alone or combined with that of the IgG subclass-was not associated with increased susceptibility to infection in persons with IgA deficiency. The results indicate that the proneness to infections observed in a population of otherwise healthy persons with IgA deficiency can only for a small part be accounted for by concomitant deficiencies of IgG subclasses. Contrary to expectations, no synergism between the deficiencies of IgA and MBL could be demonstrated.
Clinical & Experimental Immunology 07/1999; 116(3):505-8. · 3.36 Impact Factor
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ABSTRACT: To determine the prevalence of a mannan binding lectin (MBL) deficiency in children with increased susceptibility to infections and to investigate whether other coexisting immunodeficiencies affecting opsonisation are needed to render MBL deficiency clinically significant.
343 serum samples were collected from 266 children with repeated infections, a single episode of severe infection, or prolonged symptoms relating to infection. The concentrations of MBL, immunoglobulin G (IgG), M (IgM), A (IgA), and IgG subclasses (IgG1-4) were analysed.
MBL deficiency was found in nine children (3.2%), seven of whom had repeated infections or a single episode of severe infection. In two, initial symptoms and signs suggestive of infection eventually led to the diagnosis of an autoimmune disease--Still's disease in one and pauciarticular juvenile rheumatoid arthritis in the other. Among the children with MBL deficiency and infections, concomitant IgG subclass deficiency was detected in five and a transient low level of one or two IgG subclasses in two. Prevalence of an IgG subclass deficiency in children with MBL deficiency was higher than in those without (56% and 22%, respectively).
MBL deficiency alone is not an independent risk factor for infection but may be manifested in association with another humoral immunodeficiency affecting opsonisation. Among children with MBL deficiency, those with juvenile rheumatoid arthritis were overrepresented. This calls for further study.
Archives of Disease in Childhood 04/1998; 78(3):245-8. · 2.88 Impact Factor
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ABSTRACT: In this study, we determined the serum levels of mannan-binding lectin (MBL) in patients with suspected or documented infection to characterize the possible role of MBL in the susceptibility to infection. We also investigated the kinetics of MBL during the infection and correlated the concentrations of MBL with those of acute-phase reactants C-reactive protein (CRP) and group II phospholipase A2 (PLA2-II) and cytokines interleukin-1(IL-1). interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha). The frequency of MBL deficiency in the patients with signs of infection did not differ from that of controls. In four patients with MBL deficiency, the infections were caused by common pathogens and the outcome was normal. The mean MBL concentration in the patients with signs of infection was significantly higher than in the healthy controls (9.88 and 4.48 mg/l, respectively; p < 0.05). The highest mean MBL concentration was observed in patients with clinically or microbiologically documented bacterial infection. During follow-up, the MBL concentration altered individually in different patients, but no particular change in pattern in the MBL concentration could be demonstrated in any patient group. Of the acute-phase reactants in the circulation, only CRP and IL-1 showed a weak, albeit significant, negative correlation with the concentration of MBL. In conclusion, the deficiency of MBL was not shown to be an independent risk factor for infection in the adult population studied. The concentration of MBL did not follow the change in pattern of other acute-phase reactants and cytokines during the acute phase response. Therefore, measurement of the MBL concentration as an acute-phase reactant is not useful in the diagnosis or follow-up of infection. On the other hand, the deficiency of MBL can be detected reliably by serological methods even during an infection.
Apmis 08/1997; 105(8):617-22. · 1.99 Impact Factor
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ABSTRACT: Mannan-binding protein (MBP) is an acute phase reactant, and its deficiency is associated with the common opsonic defect and suspectibility to infections and atopic constitution. The aim of this study was to investigate the changes occurring in the serum level of MBP in infancy and during later childhood. We studied the serum concentration of MBP in 611 Finnish children of different ages and 110 adults by using an enzyme immunoassay. In an analysis of successive serum samples from infants at the day of birth and at the ages of 1 and 5 months, and at 1 and 2 years, the serum concentration of MBP increased significantly after birth, and was at its highest (the mean and median were 8.13 and 8.49 mgl-1, respectively) at the age of 1 month. After that, it declined to the initial level until the age of 5 months. The MBP concentration continued to decrease during childhood, and after the age of 12 years the MBP values reached the adult level. In Finnish adults the mean and median concentrations of MBP were 4.48 and 4.02 mgl-1, respectively, which seem to be higher than those reported previously in other populations. The high concentration of MBP in infants may best be explained by exposure to novel environmental antigens in early childhood, which suggests a protective role for MBP during the period of immaturity of the immunosystem. In older children the high level of MBP can probably be explained by childhood infections and the ensuing need of MBP.
Acta Paediatrica 09/1996; 85(8):906-9. · 2.07 Impact Factor
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ABSTRACT: The serum antibody response against listeriolysin O (LLO) was studied in goats experimentally infected with Listeria monocytogenes, using two sequential oral inoculations at 8 months interval. The serum IgG antibody response against LLO correlated closely with that against the whole bacterium, supporting the role of LLO as the major antigenic determinant of the humoral response against L. monocytogenes. However, only severe listeric infections were accompanied by a distinct anti-LLO antibody response, whereas milder, albeit bacteraemic infections remained only weakly responsive or totally non-responsive. Elevated anti-LLO IgG antibody levels persisted for several months after past infection and even high levels of anti-LLO IgG antibodies without evidence of past or ongoing listeriosis were found. Therefore, in the serodiagnosis of listeriosis, the determination of antiLLO antibody response may be applicable only in severe listeric infections and should always be based on IgG seroconversion.
Serodiagnosis and Immunotherapy in Infectious Disease.
