Specific interleukin-1 gene polymorphisms in Turkish patients with Behcet's disease

Vascular Involvement in Behcet's Disease: An Evaluation of 147 Cases and Literature Review

Objectives

Behcet's disease (BD) is characterized by systemic vasculitis with inflammation that can affect various body organs. In BD, vasculitis primarily manifests with venous involvement, distinguishing it from other forms of systemic vasculitis.

Methods

We retrospectively analyzed the demographic and clinical characteristics of 147 patients diagnosed with vascular BD in our center.

Results

Vascular BD cases accounted for 25.0% (147 out of 589) of all BD patients. A statistically significant correlation was found between gender and vascular involvement that was seen predominantly in males (76.9%). In 71 patients, a vascular event developed during follow-up for BD, while in 76 patients the disease was diagnosed after the occurrence of a vascular event (51.7%). The most common vascular event was deep vein thrombosis in the lower extremities (69.4%). Arterial involvement was primarily observed in the pulmonary arteries (12.9%). Patients with lower extremity deep vein thrombosis tended to be younger, while those with pulmonary artery involvement were typically older. Overall, veins were affected 4.5 times more frequently than arteries.

Conclusion

The prevalent type of venous involvement was deep vein thrombosis in the lower extremities. Thrombotic events in BD cannot be solely attributed to abnormalities in thrombotic factors. The treatment of thrombotic events in BD remains contentious, with anticoagulant efficacy being debated and immunosuppressive therapy representing the primary treatment approach. Behcet's disease should be considered when a young male patient presents with an arterial or venous vascular event, especially if it is recurrent.

Interleukin-1 gene (IL-1) polymorphism in patients with Behçet’s Disease, and its relationship with disease manifestations

Objective

The objective of this study was to investigate whether interleukin-1 (IL-1) gene polymorphisms are associated with susceptibility to Behçet’s disease (BD) and clinical manifestations of the disease.

Methods

In this cross-sectional study, we enrolled 110 patients with BD and age-and gender-matched 120 healthy controls. Five polymorphic regions of the IL-1 gene including rs 1800587 (IL1A-889 C/T), rs 2234650 (IL1R1), rs 16944 (IL1B-511 C/T), rs 315952 (IL1RN), and rs1143634 (IL1B-3954 C/T) were analyzed by using the real-time polymerase chain reaction system. Allele frequencies and genotypes were compared between groups. p ≤ 0.05 was accepted as statistically significant.

Results

The mean age of the patients with BD was 41 ± 12.4 years. The two groups were similar in terms of the age and gender distribution. The vast majority of BD patients had mucocutaneous involvement. The mean disease duration was 83.7 ± 67.8 months among the patients. The frequencies of each polymorphism in the IL-1 gene were similar between patients with BD and healthy controls.

Conclusion

The frequencies of variable IL-1 gene polymorphisms were similar between patients with BD and healthy controls.

Association between IL1B -511C/T polymorphism and Behçet's disease: a meta-analysis

Background

Many studies have investigated the relationship between the interleukin-1β gene (IL1B) −511C/T polymorphism and the risk of Behçet’s disease (BD); however, the conclusions remain controversial.

Methods

In this study, we systemically retrieved relevant studies from the Chinese Biomedicine Database, China National Knowledge Infrastructure, Embase, Cochrane Library, and PubMed databases. We then calculated the odds ratios (ORs) and 95% confidence intervals (CIs) using the meta-package Stata version 12.0.

Results

The IL1B −511C/T polymorphism was not related to BD susceptibility using any of the tested models (C vs T: OR = 1.20, 95% CI = 0.97–1.49; CC vs TT: OR = 1.27, 95% CI = 0.95–1.70; CT vs TT: OR = 1.03, 95% CI = 0.781.36; dominant model: OR = 1.12, 95% CI = 0.87–1.46; recessive model: OR = 1.27, 95% CI = 0.89–1.82). Similarly, subgroup analysis including studies consistent with the Hardy–Weinberg equilibrium revealed no association between the IL1B polymorphism and BD susceptibility.

Conclusion

This meta-analysis indicates that the IL1B −511C/T polymorphism is unlikely to affect the risk of BD; however, further large-scale, carefully designed studies are needed to verify these results.

The role of the inflammasomes in the pathogenesis of uveitis

Uveitis is a diverse group of sight-threatening intraocular inflammatory diseases usually causing eye redness, pain, blurred vision, and sometimes blindness. Although the exact pathogenesis of uveitis is not yet clear, accumulating evidences have shown that an imbalanced regulation of immune responses caused by a combination of genetic and environmental factors are implicated in the pathogenesis of this disease. As critical regulators of inflammation, inflammasomes have been assumed to play a role in the pathogenesis of uveitis. Recent studies have reported the association between a number of genetic variants in inflammasome related genes (such as NLRP3, NLRP1, NLRC4 and AIM2) with increased risk to uveitis. Mounting evidence have shown an aberrant activation of the NLRP3 inflammasome in both uveitis patients and murine models of uveitis. Some studies explored the intervention of uveitis via modulating inflammasome activity in the eye. This review aims at summarizing the main findings of these studies, proposing the possible mechanism whereby inflammasomes affect the susceptibility to develop uveitis, and giving a perspective for future studies, which may further improve our understanding about the role of inflammasomes and related cytokines in the pathogenesis of uveitis, and may hopefully lead to new therapeutics by targeting inflammasomes.

Investigation of the role of interleukin-1 receptor antagonist VNTR variant on the Behçet's disease

Objective

Behçet's disease (BD), a chronic multisystem inflammatory disorder, is mainly characterized by relapsing periods of a wide range of clinical symptoms. Several cytokine genes may play important roles in the pathogenesis of BD. Therefore, interleukin-1 receptor antagonist (IL-1Ra) gene 86bp variable number tandem repeat (VNTR) variant was investigated in patients with BD in a Turkish population.

Methods

One hundred nine patients (60 females, 49 males; the mean age±standard deviation [SD] was 36.56±9.571 years) with BD and one hundred healthy individuals (54 females, 46 males; the mean age±SD was 36.64±2.294 years) were examined in the study. For genotyping, polymerase chain reaction-restriction fragment length polymorphism analysis was employed. Data were analyzed using Statistical Package for Social Sciences (SPSS) 22.0 (IBM Corp.; Armonk, NY, USA) (p<0.05).

Results

The genotype distribution and allele frequencies of the IL-1Ra VNTR variant did not differ significantly between the patients and the controls (p>0.05). The frequency of the a1/a1, a1/a2 genotypes and a1, a2 alleles were the most common both in patients and healthy controls (p=0.37, p=0.26, and p=0.53, respectively). Also, no statistically significant difference was found between the IL-1Ra VNTR variant genotypes and clinical characteristics (p>0.05).

Conclusion

The results of this study do not support an association between the IL-1Ra VNTR variant and the risk of BD in a Turkish population. However, further studies of this variant with larger sample sizes and different ethnicities are required for confirmation.

Cytokine, C-Reactive Protein, and Heat Shock Protein mRNA Expression Levels in Patients with Active Behçet's Uveitis

Background

To investigate the gene expression levels of interleukin 10 (IL10), IL18, interferon gamma (IFNG), IFN-gamma receptor (IFNGR), C-reactive protein (CRP), and heat shock protein 70 (HSP70) in patients with active Behçet’s uveitis.

Material/Methods

Forty patients with Behçet’s disease diagnosed according to the International Study Group criteria and 30 healthy individuals were included in the study. IL10, IL18, IFNG, IFNGR, CRP, and HSP70 gene expression levels were compared.

Results

Expression levels of IL18, IFNG, IFNGR, and CRP were significantly higher in patients with active Behçet’s uveitis than in control subjects (P<0.01 for all), whereas no significant differences were found in IL10 and HSP70 gene expression levels (P>0.01 for both).

Conclusions

IL18, IFNG, IFNGR, and CRP gene expression is significantly increased in active Behçet’s uveitis. There was no significant difference between active Behçet’s uveitis patients and controls in terms of IL10 and HSP70 gene expression levels. We conclude that drugs prescribed to Behçet’s patients with active uveitis downregulate gene expression.

The absence of an association between Interleukin 1β gene polymorphisms and recurrent aphthous stomatitis (RAS)

OBJECTIVES

Recurrent aphthous stomatitis (RAS) is a chronic, ulcerative disease with a probable polygenic mode of inheritance and complex etiology with a strong immunological background. The aim of the present study was to determine the possible association between two single nucleotide polymorphisms (SNPs) of the IL-1β gene: IL-1β-511 T>C (rs16944) and IL-1β+3954C>T (rs1143634) and RAS susceptibility in a moderately large group of patients.

DESIGN

One hundred and four patients with minor, major and herpetiform RAS and 75 healthy volunteers were genotyped at IL-1β-511 T>C (rs16944) and IL-1β+3954C>T (rs1143634) using the PCR-RFLP approach. The results were statistically analysed with chi-square test and test of difference between two rates of structure, with p<0.05 assumed to be a statistically significance level (Statistica 10, StatSoft^®, Kraków, Poland).

RESULTS

There were no statistically significant differences in the genotype distribution for the IL-1β C[+3954]T polymorphism between the RAS and control groups. The frequency of IL-1β*T[-511]/*T[-511] homozygotes among the patients was significantly higher when compared to our study control (p<0.0347). The results after stratification into carriers and non-carriers of C and T alleles did not clearly indicate which SNP may be considered a risk factor for RAS.

CONCLUSIONS

The genetic association between the studied SNPs of the IL-1β gene and RAS remains controversial and requires further investigation.

The potential of genetically guided treatment in Behçet's disease

Continuous identification of specific targets and candidate genes together with novel approaches offers new promises for the future of gene therapy design in Behçet's disease (BD). Personalized medicine based on pharmacogenomics is being developed at the clinical stage to improve treatment response. Screening the whole gene and regulatory regions is important when searching for novel variants associated with such complex diseases. Different host genetic factors play significant roles in susceptibility to BD. Thus, identifying these genes responsible for susceptibility and resistance to BD may offer a notable contribution toward understanding its pathogenesis, and may lead to the development of novel prophylactic and treatment strategies. Evidenced-based treatment strategy is recommended for the management in BD patients. This review sheds light on the immunopathogenesis and pharmacogenetics of BD with special attention to the treatment targeting gene polymorphisms. In conclusion, the potential of genetically guided treatment in BD takes us back to the future for an accurate management strategy of this serious rheumatic disease. The ongoing discovery of pivotal genes related to the susceptibility, manifestations, disease activity and treatment options provide substantial hope to the reduced frequency of BD, effective control and improvement in the prognosis. Targeted gene therapy could be a leading option in the treatment armamentarium of BD.

mRNA Expression Level of Interleukin Genes in the Determining Phases of Behçet's Disease

Background

Behçet's disease (BD), first described in 1937 as a triadic complex of symptoms (oral aphthae, genital ulcers, and hypopyon uveitis), is a chronic, relapsing, multisystemic idiopathic inflammatory disease.

Objective

The objective of this study was to investigate the usability of messenger RNA (mRNA) expression of cytokine genes for following up patients with BD and also assess polymorphisms in these genes as to how they influence mRNA expression.

Methods

This study investigated the role of the IL1A -889(C/T), IL1B -511(C/T), and IL2 -330(T/G) polymorphisms by polymerase chain reaction (PCR)-restriction fragment length polymorphisms and the expression levels of the genes by real-time PCR in BD.

Results

The frequency of the IL2 -330 G allele was found to be significantly higher in patients with BD. A decreased level of IL1A gene expression was found in the patient group with clinically active BD compared to controls. Increased IL1B gene expression levels werefound in patient groups with active, inactive, or ocular BD (p<0.001). IL2 gene expression level manifested no significant change compared to controls in the patient group with clinically active BD; it increased in the groups with clinically inactive BD or ocular involvement.

Conclusion

IL1A, IL1B, and IL2 gene expression, and IL2 promoter polymorphisms, may be valuable markers for predicting risk in the development of BD. We believe that the results reveal the importance of achieving a better understanding of BD and the prospects of developing future therapeutic strategies.

The roles of genetic factors in uveitis and their clinical significance

BACKGROUND

Uveitis is a diverse group of intraocular inflammatory disease and is a significant cause of visual loss worldwide. Recent studies have identified various endogenous immune mechanisms and genetic factors that are involved in the pathogenesis of uveitis. This review provides an overview on the role of genetics in the development and clinical course of uveitis.

METHODS

PUBMED was used for literature search, and articles published from 1970 to 2012 that evaluated the genetic associations and mechanisms involved in the development and clinical features of uveitis were included.

RESULTS

Studies have demonstrated associations between various genetic factors and the development and clinical course of intraocular inflammatory conditions. Genes involved included genes expressing interleukins, chemokines, chemokine receptors, and tumor necrosis factor and genes involved in complement system, oxidation, and other intracellular molecular pathways.

CONCLUSION

Multiple genetic factors play important roles in the pathogenesis of uveitis and may influence the clinical course of uveitis. Further studies to investigate the genetic mechanisms of uveitis might identify additional genetic associations and might have the potential for identifying novel therapeutic targets in the treatment of intraocular inflammation.

Interleukin-1-related genes polymorphisms in Turkish patients with Behçet disease: a meta-analysis

OBJECTIVES

Polymorphisms in the Interleukin (IL)-1-related genes at the locations -889, -511, + 3962 and mspa1l 1100 have been investigated for possible association with Behçet's disease (BD).

METHODS

A literature-based search was conducted to identify all relevant studies. Five independent studies from Turkish population met the included criteria.

RESULTS

IL-1α -889 CT [odds ratio (OR) = 0.72, 95% confidence interval (CI) = 0.55-0.95], IL-1α -889 TT (OR = 0.61, 95% CI = 0.40-0.93), IL-1β + 3962 C (OR = 1.41, 95% CI = 1.07-1.88), IL-1β + 3962 T (OR = 0.71, 95% CI = 0.53-0.94) IL-1β + 3962 CC (OR = 2.08, 95% CI = 1.08-3.99), IL-1β + 3962 CT (OR = 0.58, 95% CI = 0.38-0.88), IL-1 receptor antagonist (IL-1 Ra) mspa1l 1100 CT (OR = 0.69, 95% CI = 0.49-0.96), IL-1 Ra mspa1l 1100 TT (OR = 1.50, 95% CI = 1.08-2.08) had a significant association with BD. The pooled estimates for IL-1α -889 C, IL-1α -889 CC, IL-1α -889 T had a non-significant association with BD.

CONCLUSIONS

IL-1α -889 CT, IL-1α -889 TT, IL-1β + 3962 C, IL-1β + 3962 T, IL-1β + 3962 CC, IL-1β + 3962 CT, IL-1 Ra mspa1l 1100 CT, IL-1Ra mspa1l 1100 TT promoter polymorphisms may confer susceptibility to BD in Turkish population.

Association of IL-1β +3954 C/T and IL-10-1082 G/A cytokine gene polymorphisms with susceptibility to tuberculosis

Tuberculosis (TB) constitutes the major cause of death due to infectious diseases. Cytokines play a major role in defence against Mycobacterium tuberculosis infection. Polymorphisms in the genes encoding various cytokines have been associated with tuberculosis susceptibility. Household contacts (HHC) are at increased risk of developing the disease. In this study, we examined the association of IL-1β and IL-10 cytokine gene polymorphisms with risk of developing tuberculosis in TB patients, their HHC and healthy controls (HC) using JavaStat and SPSS. Multifactor dimensionality reduction (MDR) analyses were performed to explore the potential gene-gene interactions. The genotype and allele frequencies of IL-1β +3954C/T polymorphism did not vary significantly between TB patients and HC. GG (P < 0.005, OR = 0.219 and 95% CI = 0.059-0.735) and GA (P < 0.0001, OR = 2.938 and 95% CI = 1.526-5.696) genotypes of IL-10-1082 G/A polymorphism were found to be significantly associated with patients versus HC. HHC with CC (P < 0.03, OR = 1.833 and 95% CI = 1.1-3.35) genotype in IL-1β and GA (P < 0.0001, OR = 4.612 and 95% CI = 2.225-9.702) genotype in IL-10 were at increased risk of developing tuberculosis. MDR tests revealed high-risk genotypes in IL-1β and IL-10 based on the association model. Our results demonstrate that the polymorphisms of IL-1β and IL-10 genes may be valuable markers to predict the risk for the development of TB in household contacts.

Interleukin-1 receptor antagonist gene polymorphism and hepcidin in rheumatoid arthritis: Correlations with clinical and laboratory indices of disease activity

Rheumatoid arthritis (RA) is a systemic autoimmune disease, which is manifested as an inflammatory polyarthritis. Authors aimed to analyze the relationship between serum hepcidin, 25 amino acid protein, concentration and the anemia profiles of RA and to estimate whether it could reflect the disease activity of RA. Also, this study was conducted to explore the linkage between interleukin-1 (IL-1) receptor antagonist gene (IL-1RN) polymorphism, proinflammatory cytokine, and RA. One hundred and eighty five RA patients were enrolled in the study. For all, the following criteria were measured: RA disease activities, anemia profiles, serum concentration of hepcidin using enzyme-linked immunosorbent assay, and DNA samples were used to study genotypes of IL-1RN gene by polymerase chain reaction. Mean concentration of serum pro-hepcidin was (93.6 ± 31.5 ng/mL) in 185 RA patients. An increased frequency of the IL-1RN*1 and IL-1RN*2 alleles was relative to active RA (DAS28 > 5.1) than those with inactive to moderate RA (DAS28 ≤ 5.1). Both hepcidin and IL-1RN gene showed significant correlation with each other as well with RA disease activity parameters and anemia profile. IL-1RN gene was significantly correlated with laboratory anemia profile apart from transferritin. There was a significant difference among pro-hepcidin concentration and IL-1RN frequency regarding patients with anemia of chronic disease and those without. In conclusion, both serum concentration of pro-hepcidin and IL-1RN genotypes frequency reflect the disease activity, regardless of the anemia states in RA patients, thus they may be another potential markers for disease activity of RA.

Common MEFV gene mutations in Turkish patients with Behcet's disease

Behcet's disease (BD) is a chronic systemic inflammatory disorder whose etiology has not been fully established yet. The MEditerranean FeVer (MEFV) gene has been identified as the cause of Familial Mediterranean Fever (FMF). BD shows similarities with FMF, in terms of clinical findings and treatments, as well as their geographical and ethnic co-occurrence. In this study we investigated common MEFV gene mutation frequencies in Turkish patients with BD in an area of Turkey where both diseases are frequently encountered. We screened 207 BD patients who had no symptoms and family history for FMF and 200 healthy subjects for five common MEFV gene mutations (E148Q, M680I, M694V, V726A, P369S) and clinical features. Seventy-five patients were found to carry a single MEFV mutation, and six patients were compound heterozygous. The difference in the frequency of the MEFV mutation between the BD and control groups was statistically significant (p<0.001, odds ratio [OR] 2.74, 95% confidence interval [CI] 1.75-4.29). The frequencies of E148Q and M680I mutations were significantly higher in the BD group (p=0.001, p=0.046, respectively). The frequency of uveitis was significantly lower in patients with the mutation than in patients without the mutation (p=0.029, OR 0.54, 95% CI 0.30-0.98). There was no statistical significance between carriers and non-carriers with respect to gender and other manifestations of BD. The frequency of the MEFV mutation was significantly higher in patients with BD compared to the healthy control group. Based on our results, MEFV mutations appear to have a role in the pathogenesis of BD.

The NLRP3 inflammasome is active but not essential in endotoxin-induced uveitis

OBJECTIVE

The inflammasome complex involving caspase-1 and nucleotide-binding domain, leucine-rich repeat containing protein (NLRP)3, also known as NALP3 or cryopyrin is important for host responses to microbial pathogens and several autoinflammatory diseases. We investigated the extent to which NLRP3 and caspase-1 control ocular interleukin (IL)-1β production and severity of uveitis (intraocular inflammatory disease) in an established, acute inflammatory uveitis model, endotoxin-induced uveitis (EIU).

METHODS

Expression of NLRP3, its adaptor molecule ASC, also known as PYCARD (PYD and CARD domain containing), and caspase-1 were examined by immunoblotting. IL-1β production was measured by enzyme-linked immunosorbent assay (ELISA). Using knockout mice, roles for caspase-1 and NLRP3 were examined in uveitis induced by intraocular injection of Escherichia coli lipopolysaccharide (LPS).

RESULTS

NLRP3, ASC, and caspase-1 proteins are constitutively expressed in eye tissue. During EIU, IL-1β protein production increases; this requires the presence of both caspase-1 and NLRP3. However, severity of EIU is not altered by deficiency in either caspase-1 or NLRP3, as assessed by both intravital microscopy and histology.

CONCLUSIONS

These data identify the importance of the NLRP3 inflammasome for IL-1β production in the eye, yet indicate that its participation in EIU is nonessential.

Impact of IL-1 signalling on experimental uveitis and arthritis

BACKGROUND

Uveitis, or inflammatory eye disease, is a common extra-articular manifestation of many systemic autoinflammatory diseases involving the joints. Anakinra (recombinant interleukin (IL)-1 receptor antagonist (Ra)) is an effective therapy in several arthritic diseases; yet, few studies have investigated the extent to which IL-1 signalling or IL-1Ra influences the onset and/or severity of uveitis.

OBJECTIVE

To seek possible links between arthritis and uveitis pathogenesis related to IL-1 signalling.

METHODS

The eyes of IL-1Ra-deficient BALB/c mice were monitored histologically and by intravital videomicroscopy to determine if uveitis developed along with the expected spontaneous arthritis in ankles and knees. Expression levels of IL-1R and its negative regulators (IL-1Ra, IL-1RII, IL-1RAcP and single Ig IL-1R-related molecule) in eye and joint tissues were compared. Differences in uveitis induced by intraocular injection of lipopolysaccharide (LPS) in mice lacking IL-1R or IL-1Ra were assessed.

RESULTS

Deficiency in IL-1Ra predisposes to spontaneous arthritis, which is exacerbated by previous systemic LPS exposure. The eye, however, does not develop inflammatory disease despite the progressive arthritis or LPS exposure. Organ-specific expression patterns for IL-1Ra and negative regulators of IL-1 activity were observed that appear to predict predisposition to inflammation in each location in IL-1Ra knockout mice. The eye is extremely sensitive to locally administered LPS, and IL-1Ra deficiency markedly exacerbates the resulting uveitis.

CONCLUSION

This study demonstrates that IL-1Ra plays an important role in suppressing local responses in eyes injected with LPS and that there is discordance between murine eyes and joints in the extent to which IL-1Ra protects against spontaneous inflammation.

Ocular Behçet disease: current therapeutic approaches

PURPOSE OF REVIEW

To alert physician to timely recognition and current treatment of recurrent hypopyon iridocyclitis or panuveitis in ocular Behçet disease (OBD).

RECENT FINDINGS

Interferon-α, rituximab, intravitreal triamcinolone, and biological response modifiers by tumor necrosis factor inhibitors such as infliximab and adalimumab are being used increasingly for the treatment of severe sight-threatening ocular inflammation including retinal vasculitis and cystoid macular edema (CME).

SUMMARY

Biological agents offer tremendous potential in the treatment of OBD. Given that OBD predominantly afflicts the younger adults in their most productive years, dermatologist, rheumatologist, internist, or general practitioners supervising patients with oculo-articulo-oromucocutaneous syndromes should be aware of systemic Behçet disease. Early recognition of ocular involvement is important and such patients should strongly be instructed to visit immediately an ophthalmologist, as uveitis management differs from extraocular involvements with high ocular morbidity from sight-threatening complications due to relapsing inflammatory attacks in the posterior segment of the eye. A single infliximab infusion should be considered for the control of acute panuveitis, whereas repeated long-term infliximab infusions were proved to be more effective in reducing the number of episodes in refractory uveoretinitis with faster regression and complete remission of CME.

Cytokines and Behcet's disease

Behcet's Disease (BD) is a systemic vasculitis of unknown etiology. Increasing studies find that a sophisticated interlacing cytokine network is closely implicated in the onset, evolution and even organ damages of the disease. Cytokines involved can be categorized as Th1 type, Th2 type, Th17 type, chemokines and other proinflammatory cytokines, etc. The vicious cycle of cytokine network plays a substantial role in the disease pathogenesis and even in organ lesions, and might be disorganized by blocking one of the key links of the cytokines, which in turn may provide essential clues to outlook the target therapy regimen of cytokine agents in BD. There have been a number of case reports of the positive efficacies of cytokine (and cytokine blocker) agents including Infiximab (Human murine chimeric Anti-TNF α monoclonal antibody), Anakinra (recombinant, non-glycosylated human IL1 receptor antagonist) etc in BD. IFN-α had been used clinically in treating BD with uveitis with beneficial efficacy ever since the 1980s. The studies to date suggested that IL6, IP10 are involved in BD with nervous system lesions, IL17, IL18 are relevant to the superimposed uveitis in patients with BD. Some cytokines i.e. IL8, RANTES, MIP-1α are associated with the disease activity, whereas others are exemplified by that of IL10, whose level shows negative relevance to the disease activity, might be potentially cytokine of protecting effect. According to the related genetic study, the SNPs of numerous cytokines including IL1, TNFα, IFNγ, IL12, and IL18 are pertinent to BD. The recent GWAS (Genome Wide Association Studies) demonstrated that SNPs in the IL10 and IL23R-IL12RB2 region are associated with the disease. Most studies nowadays are confined within the cytokines in the peripheral blood levels, owing to the potentially significant roles of certain cytokines in local lesions. It warrants further in-depth study to address this issue. Moreover, it deserves multi-centre study considering the unique geographical "silk road" display picture of the disease.

New insights into the pathogenesis of Behçet's disease

Behçet's disease (BD) is a recurrent systemic inflammatory disorder of unknown origin characterized by oral and genital mucous ulcer, uveitis, and skin lesions. Involvement of large vessels, central nervous system (CNS), gastrointestinal tract and thrombotic events are less frequent but can be life threatening. The aim of this review is to provide new insights into the pathogenesis of BD. Over the past year substantial advances have been done in the understanding of the genetic [1,2] and immunology [3] of BD. BD is at the crossroad between autoimmune and autoinflammatory syndromes. In common with autoimmune diseases BD shares class I MHC association. However, in contrast to autoimmune disorders, BD has clinical features that seem to be mostly autoinflammatory. The pathogenesis of BD is still unknown, but major determinants of the genetic and immune system abnormalities have been reported recently. Triggering infectious factors are supposed to participate in the outbreak of BD in genetically predisposed patients. Two recent large genome-wide association study (GWAS) conducted in Turkey and Japan reported association between single nucleotide polymorphism (SNP) of interleukin (IL)-10 and IL-23R/IL-12RB2 genes and BD. New insights into the perturbations of T cell homeostasis of BD recently emerged. We have recently demonstrated the promotion of Th17 responses and the suppression of regulatory T cells (Tregs) that were driven by interleukin (IL)-21 production and that correlates with BD activity. Inflammatory cells within BD inflammatory lesions included mostly neutrophils, Th1 and Th17 cells, and cytotoxic CD8+ and γδ T cells. Altogether, the recent progresses in the knowledge of BD pathogenesis pave the way for innovative therapy.

The skin pathergy test: innately useful?

Pathergy is the term used to describe hyper-reactivity of the skin that occurs in response to minimal trauma. A positive skin pathergy test (SPT), characterised by erythematous induration at the site of the needle stick with a small pustule containing sterile pus at its centre, is among the criteria required for a diagnosis of Behçet's disease (BD) and in certain population has been shown to be highly specific for this condition. Problems with standardising the induction manoeuvre for the SPT as well as the method of assessment of the response have limited the usefulness of the SPT in the clinical setting. Extensive investigation into histopathological and immunological aspects of pathergy has led to a number of hypotheses relating to the aetiology of the skin pathergy reaction and the disease itself, but the cause is considered to be unknown. Pathergy lesions, the development of new skin lesions or the aggravation of existing ones following trivial trauma, are also reported in pyoderma gangrenosum and has been noted in other neutrophilic dermatoses such as Sweet's syndrome. The response of such patient groups to the systematic application of the SPT has not been described. We propose that a new way of considering the pathergy reaction is to see it as an aberration of the skin's innate reactivity from a homeostatic reactive mode closely coupled to tissue healing to an abnormal destructive/inflammatory mode. Our understanding of BD and other similar conditions would profit by more detailed mechanistic knowledge of skin homeostasis to minimal trauma in both health and disease through a more structured and systematic use of the SPT.

Common FMF alleles may predispose to development of Behcet's disease with increased risk for venous thrombosis

BACKGROUND

Behcet's disease (BD) is an inflammatory disorder of unknown cause, associated with vasculitis. Arterial or venous thrombosis occurs in about 25% of BD patients. Familial Mediterranean fever (FMF) is another inflammatory disorder, which stems from mutations in the FMF gene (MEFV) and shares a number of features with BD.

OBJECTIVE

MEFV analysis in patients with BD suggests that mutated MEFV may act as a susceptibility gene in BD. We studied the rate and the clinical correlates of MEFV mutations in Israeli BD patients.

METHODS

Included were 54 BD patients who satisfied the International Study Group criteria for BD. All BD patients were genotyped using polymerase chain reaction (PCR) and restriction enzyme analysis for the three most common MEFV mutations (M694V, V726A, and E148Q). The association between BD manifestations and MEFV alleles was analysed.

RESULTS

Twenty-one BD patients were found to carry a single MEFV mutation and three additional patients were compound heterozygotes, a frequency significantly higher than that expected for ethnically matched healthy individuals. There were no statistically significant differences between carriers and non-carriers with respect to gender, frequency of HLA B5 antigen, cutaneous lesions, joint disease, and severity score. However, carriers did experience thrombosis more often [54% vs. 17%, p<0.005, odds ratio (OR) = 6.9, 95% confidence interval (CI) 1.75-26.9] and uveitis less often (20% vs. 40%, p<0.05, OR = 0.2, 95% CI 0.04-0.92).

CONCLUSIONS

MEFV appears to be a susceptibility and modifier gene in BD.

Behçet's disease--a contemporary review

Behçet's disease (BD) is a systemic vasculitis disorder of unknown etiology, characterized by relapsing episodes of oral aphthous ulcers, genital ulcers, skin lesions and ocular lesions. It can affect other systems including vascular, gastrointestinal and neurological systems. It occurs most frequently in an area that coincides with the Old Silk Route (between latitudes 30 degrees and 45 degrees north in Asia and Europe). BD is slightly more frequent and has a worse clinical course in men. It is believed to be due to an auto-immune process triggered by an infectious or environmental agent in a genetically predisposed individual. HLA-B51 is the most strongly associated risk factor. The International Study Group (ISG) for Behçet's Disease created a set of criteria for the diagnosis of BD. Available treatments include corticosteroids, azathioprine, cychlophosphamide, cyclosporine A, interferon-alpha, anti-tumour necrosis factor alpha agents, among others. BD has a variable course characterized by relapses and remissions. Prognosis depends on the clinical involvement. Loss of visual acuity and neurological disease are major causes of morbidity and disability.

Molecular genetic analysis of interleukin-1 promoter and receptor antagonist tandem repeat polymorphisms among HLA-identical renal transplant recipient and donor pairs

The cytokine gene polymorphisms as well as the minor histocompatibility antigen (mHAg) disparities have been thought to result in transplant graft rejection and graft-versus-host reaction between HLA-identical donor/recipient pairs. We detected interleukin (IL)-1 promoter and receptor antagonist tandem repeat polymorphisms among 21 HLA identical renal transplant recipient and donor pairs; of 21 pairs, 15 (71%) showed at least one locus difference between donor and recipient, and 73% of the pairs with the disparities at these loci showed either recipient to donor (R-->D) or donor to recipient (D-->R) positive CD4+ cell response measured by a modified Cylex assay developed in our laboratory. Allele 2 of IL-1 receptor antagonist genotype (IL-1ra VNTR), a gene associated with an increasing IL-1beta production, was detected in the three recipients who developed rejections. One HLA-identical pair that had variations on all four loci of IL-1 gene cluster consistently showed positive CD4+ cell immune responses between the donor and the recipient. This study may provide information of the role of non-HLA genes participating in allograft rejection; this demonstrates that in addition to the disparities of the mHAgs, the non-HLA antigens have to be considered as risk factors in HLA-identical solid organ transplantation.

Interleukin 1 beta gene polymorphism and risk of cervical cancer

OBJECTIVE

To determine whether a polymorphism at position +3953 in exon 5 of the lL-1beta gene (IL-1beta +3953), a condition associated with an increased risk for a number of inflammatory diseases, is also involved in the development of cervical cancer.

METHOD

We isolated DNA from peripheral blood in 150 women with cervical cancer and 200 healthy controls, and IL-1beta +3953 allele polymorphism was determined by polymerase chain reaction.

RESULTS

Genotypes A1/A2 and A2/A2+A1/A2 were associated with increased risk of cervical cancer (odds ratio [OR], 2.88; 95% confidence interval [CI], 1.78-4.67; P<0.001 and OR, 2.85; 95% CI, 1.77-4.6; P<0.001, respectively). The risk in a passive smoker with A2/A2 or A1/A2 genotype was increased more than 5-fold (OR, 5.69; 95% CI, 2.61-12.50; P<0.001) compared with a nonsmoker with the A1/A1 genotype.

CONCLUSION

This study provides evidence of an association between lL-1beta +3953 polymorphism and risk of cervical cancer.

A method of oligochip for single nucleotide polymorphism genotyping in the promoter region of the interleukin-1 beta gene and its clinical application

Single nucleotide polymorphisms (SNPs) can contribute to genetic predispositions or serve as genetic markers that are associated with complex diseases. So far, a few SNP arrays containing a limited number of SNPs have been used in routine genetic testing. This study described an oligochip-based method that genotypes two SNPs (-511 and -31) in the promoter region of the interleukin (IL)-1 beta gene. The sensitivity of this SNP genotyping method is derived from polymerase chain reaction (PCR)-amplified allele-specific primer-probes with a biotin label incorporated from the reverse primers. The amplified primer-probes can specifically hybridize with the oligonucleotides that are spotted on the oligochip. This oligochip-based method successfully discriminated the two biallelic SNPs with 9 different genotypes and all the genotyping results are in concordance with those from PCR restriction fragment length polymorphism (RFLP) analysis. Selective samples with various genotypes were also confirmed by direct sequencing. This method was applied in the genotyping of the patients with tuberculosis or gastric cancer and healthy controls. In the case control study, our genotyping data supported the reported association between gastric cancer and the genotypes of IL-1 beta -31 TT and -511 CC (p < 0.05). We also found that there is a significant difference of IL-1 beta -31 genotypes between 98 tuberculosis patients and healthy controls (p < 0.002). All of our results demonstrated that the oligochip can effectively and accurately identify SNP genotypes in the IL-1 beta promoter region.

Relationship between periodontal findings and specific polymorphisms of interleukin-1alpha and -1beta in Turkish patients with Behçet's disease

Genetic factors predispose individuals to Behçet's disease (BD) and periodontal disease. IL-1 has been implicated in the pathogenesis of both BD and periodontal disease. The relationship between periodontitis and pathogenesis of BD has not yet been determined. Since IL-1 has been implicated in the pathogenesis of both BD and periodontal disease, we aimed to investigate the possible relation of the periodontal scores and SNPs of IL-1alpha-889C/T, IL-1beta-511C/T, and IL-1beta+3962T/C with BD compared to healthy controls (HC) and recurrent aphtous stomatitis (RAS). A total of 155 Turkish individuals were enrolled in this study. The periodontal status of all subjects was evaluated according to the WHO community periodontal index of treatment needs. For genotyping, CTS-PCR-SSP was employed. IL-1alpha-889C allele was significantly higher in BD patients (p = 0.03) and RAS (p = 0.02) compared to HC. The frequency of IL-1beta+3962T allele was significantly higher in RAS patients compared to HC (p = 0.015). Male gender (p = 0.04), age (p = 0.02) and carrying IL-1beta-511T allele (p = 0.01) were found to be a significant risk factors for higher periodontal scores in Turkish population. We can speculate that susceptibility to the development of periodontal disease could be influenced by IL-1 SNPs. Periodontitis-induced autoinflammatory response also may play a role in the development/severity of BD and RAS via IL-1 gene alteration.

From inflammasomes to fevers, crystals and hypertension: how basic research explains inflammatory diseases

Pattern-recognition receptors, such as Toll-like receptors and NOD-like receptors (NLRs), are able through the recognition of pathogen-associated molecular patterns and danger-associated molecular patterns to sense microbe-dependent and microbe-independent danger and thereby initiate innate immune responses. In some autoinflammatory conditions, abnormalities in NLR signaling pathways are involved in pathogenesis, as exemplified by NOD2 mutations associated with Crohn's disease. Some other NLRs are components of the inflammasome, a caspase-1- and prointerleukin-1beta-activating complex. Clinical and experimental studies are beginning to reveal the central role of the inflammasome in innate immunity. Here, we focus on monogenic hereditary inflammatory diseases, such as Muckle-Wells syndrome, which are associated with mutations in proteins that modulate the activity of the inflammasome, and on some multifactorial disorders, such as Type 2 diabetes and hypertension.

Behcet disease in adult Druzes in north Israel: the influence of ethnic origin on disease expression and severity

BACKGROUND

Behcet's disease (BD) is known to vary in severity and manifestations in different populations.

OBJECTIVE

In an attempt to sort out genetic and environmental influences on disease expression, we carried out a study to assess the clinical features of BD in the adult Druze and Arab populations in north Israel, comparing 2 disparate ethnic groups of similar genetic background inhabiting the same geographic region.

METHODS

We compared 23 Druze and 30 Arab patients with BD. All patients fulfilled the classification criteria of the International Study Group for BD.

RESULTS

Manifestations were similar in 2 groups. The most frequent BD manifestations among the Druzes were recurrent oral aphthae (100%) and genital aphthae (61%) versus 100% and 53% in Arab patients, followed by inflammatory ocular involvement, 65% versus 53%, respectively. Arthritis was noted in 39% of Druze, with 27% in Arabs. Anterior uveitis occurred in 9 Druze patients (48%) and panuveitis in 4, with no case of blindness when compared with 30% with anterior uveitis, 4 with panuveitis, and 4 cases of blindness (P < 0.04) among the Arabs. One Druze BD patient had deep vein thrombosis versus 8 Arab patients (P < 0.017). No pulmonary embolism, aortic aneurysm, nor valvular involvement was documented in the Druze versus 1 case of each in Arabs. No case of neuro-Behcet was reported in Druzes versus 6 cases of neuro-Behcet among Arabs (P < 0.023). The severity score was 4.0 (SD, 1.2) in Druze and 5.8 (SD, 1.9) in Arabs (P = 0.0004). The prevalence of HLA B51 did not differ significantly between the groups.

CONCLUSION

Druze BD patients in Israel have a milder disease than do Arabs, similar to observations in familial Mediterranean fever. Druze BD patients had significantly less severe ocular disease and neurologic manifestations. Our results suggest an ethnic influence on expression of BD not related to HLA B 51.

HLA-B51 gene and its expression in association with Behçet’s Disease in Denizli Province of Turkey

Behçet's Disease (BD) is a multisystemic inflammatory disorder as a triad of symptoms including recurrent oral and genital aphthous ulceration, and uveitis with unknown pathogenesis. Many researchers have tried to investigate the association of HLA-B51 gene with the BD. We aimed to investigate the association of the HLA-B51 gene and its expression, also polymorphic structure by PCR, RT-PCR and sequence specific oligonucleotide primers and probes in BD patients (n: 35) and control group (n: 50). According to our results, we did not observe any association in between HLA-B51 gene, its polymorphism, expression and BD patients.

Relationship between periodontal findings and Behçet's disease: a controlled study

BACKGROUND

Behçet's disease (BD) is a chronic, relapsing, systemic vasculitis of unknown aetiology. The involvement of oral mucosal surfaces represents the onset feature of the disease in the majority of patients.

OBJECTIVE

The aim of this study was to evaluate the periodontal status of BD patients and then compare with recurrent aphthous stomatitis (RAS) patients and healthy controls. We also determined the relationship between the periodontal condition and the clinical severity of the disease in BD patients.

METHODS

Eighty-six patients with BD, 63 patients with RAS and 82 healthy subjects were included in the study. The periodontal status of all subjects was evaluated according to the community periodontal index of treatment needs (CPITN). BD patients were also assessed for clinical severity score (CSS) as described previously.

RESULTS

The mean CPITN were observed to be higher in BD patients (1.79 +/- 0.96) compared with RAS patients (1.22 +/- 0.87) and healthy controls (1.18 +/- 0.98) (p<0.001). There was a positive association between CSS and CPITN (p=0.017) in BD patients.

CONCLUSION

Our results showed that periodondal status is worse in BD patients and associated with disease severity. We can speculate that periodontitis may induce a systemic inflammatory process that may contribute to the development and/or progression of BD.

T helper 1 type cytokines polymorphisms: association with susceptibility to Behçet’s disease

The pathogenesis of Behçet's disease (BD) is not fully understood and immunological abnormalities and genetic factors have been investigated. Because serum concentrations of mainly T helper 1 (Th1) type cells have been reported to be increased in BD, we aimed to investigate whether certain cytokine polymorphisms might represent a risk factor for developing BD. We genotyped 80 patients with BD and 105 healthy controls for interleukin (IL)-1 alpha (T/C -889), IL-1 beta (C/T -511, T/C +3962), IL-1R (C/T pst11970), IL-1RA (T/C mspa111100), IL-2 (T/G -330), IL-12 (C/A -1188), interferon (IFN)-gamma (A/T UTR 5644), and TNF-alpha (G/A -238) polymorphisms. Analyses of cytokine polymorphisms were performed with PCR-SSP. The genotype and allele frequencies of the patients and controls were compared and the association between the polymorphisms of the cytokines with the clinical findings was investigated. Genotype distribution showed significant differences between the patients and the controls for the IL-1 alpha -889, IL-1 beta -511, IL-1 beta +3962, IL-1R, IL-12, IFN- gamma, and TNF-alpha cytokines. We didn't observe significant difference in genotypic frequencies of IL-1RA and IL-2 in our study. Comparison of the IL-1 alpha -889, IL 1 beta -511, and IL 1 beta +3962 genotype frequencies showed significant increase in CC genotype between the patients and the controls. The individuals with IL-1R TT polymorphism had a higher risk for BD compared to patients with CT/CC polymorphism. Comparison of IL-12, IFN- gamma, and TNF-alpha, genotype frequencies showed significant increase in CA, AA, and AA genotypes between the patients and controls, respectively. The frequencies of genotypes according to the clinical features of the patients with BD did not show a significant difference (p>0.05). Our study suggests that development of BD might be determined by various cytokine gene polymorphisms. However, further studies on larger numbers of cases are needed before definite conclusions can be drawn.

Cytokines and chemokines in uveitis: is there a correlation with clinical phenotype?

Uveitis is a general term for intraocular inflammation and includes a large number of clinical phenotypes. As a group of disorders, it is responsible for 10% of all registered blind patients under the age of 65 years. Immune-mediated uveitis may be associated with a systemic disease or may be localized to the eye. The pro-inflammatory cytokines interleukin (IL)-1beta, IL-2, IL-6, interferon-gamma and tumor necrosis factor-alpha have all been detected within the ocular fluids or tissues in the inflamed eye together with others, such as IL-4, IL-5, IL-10 and transforming growth factor-beta. The chemokines IL-8, monocyte chemoattractant protein-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and fractalkine are also thought to be involved in the associated inflammatory response. There have been a number of studies in recent years investigating cytokine profiles in different forms of uveitis with a view to determining what cytokines are important in the inflamed eye. This review attempts to present the current state of knowledge from in vitro and in vivo research on the inflammatory cytokines in intraocular inflammatory diseases.

Physiopathologie de la maladie de Behçet

SUBJECT

Pathophysiology of Behçet's disease (BD) is complex. Recent experimental data shed new light on the mechanisms leading to organ lesions.

MAIN ISSUES

Neutrophils and cytotoxic lymphocytes are now recognized as key effector cells in BD. Genetic susceptibility, environmental factors (virus and/or bacterial infections), inflammatory response abnormalities (heat shock proteins, dysregulated NO production) and abnormal immune response play also a major role in BD pathogeny.

PERSPECTIVES

Better understanding of the BD pathophysiology will allow the development of new therapies more specific of BD.

Interleukin-18 Promoter Polymorphisms in Patients With Behçet’s Disease

Behçet's disease (BD) is an idiopathic systemic inflammatory disease and is considered to be a T helper 1 (Th1) type cytokine driven disorder. Moreover, levels of interleukin-18 (IL-18), a pivotal mediator of Th1 cytokine response, have been reported to be upregulated in BD. Therefore, we investigated the distribution of IL-18 promoter -607 C/A and -137 G/C polymorphisms in 103 BD patients (mean age 41.0 years; 48 male, 55 female) using allele-specific-polymerase chain reaction. As compared with healthy control subjects, BD patients had a significantly higher frequency of the -607 CC genotype (42.7% vs 23.3%, odds ratio [OR] = 2.455, 95% confidence interval [CI] = 1.350-4.461, p(c) = 0.021) and a higher frequency of the -607 C allele (60.7% vs 48.1%, OR = 1.668, 95% CI = 1.129-2.464, p = 0.0101). Haplotype analysis showed that BD patients had significantly less -607A/-137G haplotype (27.3% vs 44.2%, OR = 0.469, 95% CI = 0.268-0.820, p(c) = 0.032) and -607A/-137G haplotype homozygote (5.8% vs 20.4%, OR = 0.242, 95% CI = 0.096-0.612, p(c) = 0.014) than control subjects. In addition, the frequency of -607C/-137G haplotype homozygote was significantly higher in BD patients than control subjects (48.5% vs 20.4%, OR = 3.684, 95% CI = 1.997-6.791, p(c) = 0.0014). Although there were no associations between the polymorphisms and clinical manifestations or severity, patients with the -607 CC genotype or -607C/-137G haplotype homozygote showed significantly earlier symptom development (p = 0.034 by ANOVA; p = 0.009 by t-test, respectively) than those with other genotypes or diplotypes. These results suggest that the IL-18 promoter gene is a candidate susceptibility gene in BD patients.

Evaluation of leptin level and Ob gene polymorphism in patients with Behcet's disease

The present study was aimed to evaluate serum leptin level and the frequency of oligopolymorphic codon 25 (CAA/CAG) of Ob gene in Behcet's disease. Eighty-seven patients with Behcet's disease and 85 healthy controls with matched age, gender and body mass index were included in the study. Serum leptin level was determined and genotype of codon 25 of Ob gene was performed by using the PCR amplification after DNA extraction. Serum leptin concentration of the patients with Behcet's disease (23.8 +/- 22.8 ng/ml) was higher than that of the control groups (17.1 +/- 14.7 ng/ml). The patients with Behcet's disease and control subjects showed CAA/CAA genotype, indicating the presence of no polymorphism. Neither Behcet's disease nor serum leptin level was found to be related to codon 25 polymorphism. We concluded that leptin 25CAG polymorphism is not associated with Behcet's disease and serum leptin level.

CTLA-4 gene 49A/G polymorphism in Turkish patients with Behçet's disease

Genetic factors predisposing individuals to Behçet's disease (BD) are considered to play important roles in the development of the disease. Patients with BD exhibit elevated levels of pro-inflammatory cytokines, and affected organs show a significant neutrophil and lymphocyte infiltration. Current evidence suggests that the activated lymphocytes contribute to neutrophil and endothelial cell activation in these patients. The cytotoxic T lymphocyte-associated antigen (CTLA)-4 molecule plays an important role in immune regulation by downregulating T-cell activation, and the CTLA-4 49A/G polymorphism in the exon 1 has been shown to be associated with a number of autoimmune diseases. In an attempt to demonstrate whether there is an association of the CTLA-4 49A/G polymorphism with BD in the Turkish population, we genotyped 59 Turkish patients and 99 healthy individuals for single-nucleotide polymorphisms. For this purpose, genomic DNA was obtained from the peripheral blood of individuals and the region of interest was amplified using PCR. Genotyping was performed using the BbvI restriction endonuclease. It was shown that the distribution of the CTLA-4 exon 1 49A/G allele and genotype frequencies did not differ between patients with BD and healthy controls. However, allele and genotype frequencies of CTLA-4 49 A and A/A were significantly higher in patients with ocular involvement compared with patients without these symptoms (90.6% vs. 65.1%, odds ratio (OR) = 9.67, P = 0.011; and 81.25% vs. 39.5%, OR = 9.56, P = 0.015, respectively). A statistically significant difference in the A allele frequency was observed in patients with erythema nodosum-like lesions (86.1% vs. 65.8%, OR = 6.24, P = 0.04). There was also an increase in A/A genotype frequency, but the difference was not statistically significant (72.2% vs. 41.5%, OR = 6.5, P = 0.068). Our data suggest that BD patients with ocular involvement and erythema nodosum-like lesions have a higher frequency of both the A allele and the A/A genotype at position 49 of exon 1 of CTLA-4. These results may also indicate that CTLA-4 is a disease-modifying rather than a susceptibility gene for BD.