Meta-Analysis of Associations Between Interleukin-10 Polymorphisms and Susceptibility to Vasculitis

Genetic and Non-Genetic Contributions to Eosinophilic Granulomatosis with Polyangiitis: Current Knowledge and Future Perspectives

In this work, we present a comprehensive overview of the genetic and non-genetic complexity of eosinophilic granulomatosis with polyangiitis (EGPA). EGPA is a rare complex systemic disease that occurs in people presenting with severe asthma and high eosinophilia. After briefly introducing EGPA and its relationship with the anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAVs), we delve into the complexity of this disease. At first, the two main biological actors, ANCA and eosinophils, are presented. Biological and clinical phenotypes related to ANCA positivity or negativity are explained, as well as the role of eosinophils and their pathological subtypes, pointing out their intricate relations with EGPA. Then, the genetics of EGPA are described, providing an overview of the research effort to unravel them. Candidate gene studies have investigated biologically relevant candidate genes; the more recent genome-wide association studies and meta-analyses, able to analyze the whole genome, have confirmed previous associations and discovered novel risk loci; in the end, family-based studies have dissected the contribution of rare variants and the heritability of EGPA. Then, we briefly present the environmental contribution to EGPA, reporting seasonal events and pollutants as triggering factors. In the end, the latest omic research is discussed and the most recent epigenomic, transcriptomic and microbiome studies are presented, highlighting the current challenges, open questions and suggesting approaches to unraveling this complex disease.

Regulatory T cells and systemic vasculitis

PURPOSE OF THE REVIEW

Emerging data suggest that regulatory T-cells (Treg) alterations play a major role in systemic vasculitis pathophysiology. We performed a systematic review of recent advances in the role of Treg and interleukin (IL)-10 in the pathogenesis and treatment of systemic vasculitis, including giant cell arteritis (GCA), Takayasu arteritis, Behçet's disease, antineutrophil cytoplasm antibodies (ANCA) associated vasculitis (AAV), and cryoglobulinemia associated vasculitis.

RECENT FINDINGS

Emerging data suggest that Treg deficiencies are disease-specific, affecting distinct pathways in distinct vasculitides. Decreased peripheral blood frequencies of Treg are described in all vasculitis when compared to healthy donors. Altered Treg functions are reported in GCA, Takayasu arteritis, AAV, and Behçet's disease with different mechanisms proposed. Treatment with biologics, and sometimes other immunosuppressants, may restore Treg frequencies and/or immune activity with significant differences in active disease or disease in remission in several systemic vasculitis. IL-10 is elevated in GCA, AAV, cryoglobulinemia associated vasculitis. In Behçet's disease, IL-10 is decreased in peripheral blood and elevated in saliva. In Takayasu arteritis, IL-10 levels were essentially elevated in patients' vessel wall. Several new therapeutic approaches targeting Treg and Il-10 (low dose IL-2, CAR Treg…) are developed to treat patients with systemic vasculitis.

SUMMARY

Treg and IL-10 play a central role in the regulation of inflammation in vasculitis and new targeting approaches are emerging.

Association between interleukin 12B and interleukin 23R gene polymorphisms and systemic lupus erythematosus: a meta-analysis

OBJECTIVE

To determine whether polymorphisms of interleukin 12B (IL12B) and IL23 receptor genes (IL23R) confer susceptibility to systemic lupus erythematosus (SLE).

METHODS

A meta-analysis was conducted to analyze the associations between SLE and IL12B rs3212227 and rs17860508 and IL23R rs7517847, rs10489629, rs10889677, rs1004819, rs11209026, rs11209032, rs1343151, and rs1884444 polymorphisms using allele contrast, dominant, recessive, heterozygote, and homozygote models. Ten studies involving 1989 patients with SLE and 2394 controls were considered for the meta-analysis.

RESULTS

The meta-analysis using the homozygote model revealed that IL23R rs10889677 was significantly associated with SLE susceptibility in the overall population (AA vs. CC) (odds ratio = 0.70, 95% confidence interval = 0.50-0.98) but not in the Asian population. Other polymorphisms of IL12B and IL23R were not significantly associated with SLE protection.

CONCLUSIONS

These findings suggest that the IL23R rs10889677 polymorphism confers SLE susceptibility to individuals of certain ethnicities. (Research Registry number: 1268).

A Darwinian View of Behçet's Disease

Behçet's disease (BD) is a multisystem inflammatory disorder of unknown etiology, characterized by oral and genital ulceration, with other complications including eye, skin, joint, and central nervous system (CNS) lesions. Diagnosis is based on clinical findings, which may differ between patients. There is a strong genetic basis for BD; however, only a few genes have been associated with the disease across the geographical spread of BD. In this article, we discuss the history and combination of genes involved in this complex disease in relation to the geographical range and present our view that the disease has developed from a Darwinian perspective, with different gene polymorphisms that affect the same biological pathway. Moreover, these mutations individually are protective mechanisms against the disease relevant to each region, which affected both archaic and modern humans.

Associations between interleukin 18 gene polymorphisms and susceptibility to vasculitis: A meta-analysis

Interleukin 18 (IL18), a pro-inflammatory cytokine, affects the development and progress of vasculitis. The production, expression, and function of this cytokine are affected by polymorphisms of promoter region of the IL18 gene. In this study, a meta-analysis of the associations between several IL18 polymorphisms and susceptibility to vasculitis was performed. Published literature from PubMed and Embase were retrieved. In total, nine studies comprising 1006 patients with vasculitis and 1499 controls combined, and the investigating the rs187238, rs194618, and rs360719 polymorphisms of the promoter region of the IL18 gene, were included in the meta-analysis. Pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated with fixed-effects model or random-effects model. The recessive model of the rs194618 polymorphism was found to be significantly associated with a high susceptibility to vasculitis (OR = 1.54, 95% CI = 1.02–2.33, P = 0.04), especially in the Mongoloid race, where the A allele of rs194618 was associated with a low risk of the disease (OR = 0.77, 95% CI = 0.62–0.95, P = 0.01). By contrast, the rs187238 and rs360719 polymorphisms were not associated with this inflammatory condition. This meta-analysis showed that some IL18 polymorphisms are associated with susceptibility to vasculitis. (Sarcoidosis Vasc Diffuse Lung Dis 2020; 37 (2): 203-211)

The associations between interleukin 10 polymorphisms and susceptibility to autoimmune uveitis - a meta-analysis

Autoimmune uveitis is an ocular inflammatory disease that is associated with genetic factors. Interleukin 10 (IL-10) is an immune-regulatory cytokine of autoimmune diseases. IL-10 is considered a candidate gene for uveitis. We evaluate the association of IL-10 with susceptibility to autoimmune uveitis. The results from seven studies were pooled in the meta-analysis, covering a total of 2893 cases of uveitis and 4873 controls. Published literature from MEDLINE and Embase was retrieved. Meta-analyses were conducted on the associations between autoimmune uveitis and the -1082 A/G and -819 C/T polymorphisms of the IL-10 gene. The meta-analysis revealed no association between uveitis and the IL-10 -1082 A allele (OR = 0.91, 95% CI = 0.64-1.30, p = 0.62). The recessive, dominant, and homozygous models of the IL-10 -1082 A/G allele also suggested no association between autoimmune uveitis and each genotype. The meta-analysis revealed significant association between uveitis and the -892 C allele (OR = 0.81, 95% CI = 0.67-0.98, p = 0.03). In addition, significant association was found in homozygous models (OR = 0.58, 95% CI = 0.36-0.92, p = 0.02). However, the dominant and recessive models of the IL-10 -819 C/T polymorphisms showed no association between uveitis and each genotype. This meta-analysis showed that the -1082 A/G polymorphisms of IL-10 were not associated with autoimmune uveitis, but the -819 C/T polymorphisms were significantly associated with uveitis.

Association of the TNF-α gene promoter polymorphisms at nucleotide -238 and -308 with acne susceptibility: a meta-analysis

BACKGROUND

The tumour necrosis factor (TNF)-α -238 and -308 polymorphisms are potential candidate genes that may serve as modulators in susceptibility to acne.

AIM

We performed a meta-analysis of case-control studies to assess the association of the TNF-α -238 and -308 polymorphisms with acne susceptibility.

METHODS

The PubMed, EMBASE, Scopus, SinoMed and China National Knowledge Infrastructure databases were systematically searched to identify eligible studies. OR and 95% CI were calculated to evaluate the association.

RESULTS

We identified seven independent case-control studies up to September 2017. The results revealed an association between the A allele of the TNF-α -238 polymorphism and increased susceptibility to acne in Asian (OR = 1.61, 95% CI 1.08-2.40) but not in European (OR = 1.10, 95% CI 0.63-1.93) populations. For the TNF-α -308 polymorphism, the minor A allele was associated with increased acne susceptibility in Asian (OR = 1.93, 95% CI 1.15-3.24) and Turkish (OR = 4.14, 95% CI 2.25-7.61) populations, but not in European (OR = 1.17, 95% CI 0.66-2.06) or Arab (OR = 0.88, 95% CI 0.64-1.22) populations. Egger test found no evidence of publication bias.

CONCLUSION

Our findings suggest that the TNF-α -238 A allele is associated with increased susceptibility to acne in Asian but not in European populations, while the TNF-α -308 A allele is associated with increased susceptibility to acne in Asian and Turkish populations but not in European or Arab populations.

Genetic Variants in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Bayesian Approach and Systematic Review

A number of genome-wide association studies (GWASs) and meta-analyses of genetic variants have been performed in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. We reinterpreted previous studies using false-positive report probability (FPRP) and Bayesian false discovery probability (BFDP). This study searched publications in PubMed and Excerpta Medica Database (EMBASE) up to February 2018. Identification of noteworthy associations were analyzed using FPRP and BFDP, and data (i.e., odds ratio (OR), 95% confidence interval (CI), p-value) related to significant associations were separately extracted. Using filtered gene variants, gene ontology (GO) enrichment analysis and protein⁻protein interaction (PPI) networks were performed. Overall, 241 articles were identified, and 7 were selected for analysis. Single nucleotide polymorphisms (SNPs) discovered by GWASs were shown to be noteworthy, whereas only 27% of significant results from meta-analyses of observational studies were noteworthy. Eighty-five percent of SNPs with borderline p-values (5.0 × 10-8 < p < 0.05) in GWASs were found to be noteworthy. No overlapping SNPs were found between PR3-ANCA and MPO-ANCA vasculitis. GO analysis revealed immune-related GO terms, including "antigen processing and presentation of peptide or polysaccharide antigen via major histocompatibility complex (MHC) class II", "interferon-gamma-mediated (IFN-γ) signaling pathway". By using FPRP and BFDP, network analysis of noteworthy genetic variants discovered genetic risk factors associated with the IFN-γ pathway as novel mechanisms potentially implicated in the complex pathogenesis of ANCA-associated vasculitis.

Association between interleukin-10 polymorphisms and juvenile idiopathic arthritis: a meta-analysis

INTRODUCTION

The aim of this review is to investigate IL-10 polymorphisms (-1082 G/A, -819 C/T, and -592 C/A) and their association with susceptibility to JIA.

EVIDENCE ACQUISITION

A meta-analysis was conducted after database search for relevant articles (MEDLINE and EMBASE).

EVIDENCE SYNTHESIS

A total of seven studies involving 1495 patients and 1670 controls were considered in the meta-analysis. There was no association between the IL-10 -1082 G/A, -819 C/T, and -592 C/A polymorphisms and JIA in allele contrast and any of the genetic models (allele contrast: odds ratio [OR] 0.90, 95% confidence interval [CI] 0.79-1.02, P=0.09; OR=0.97, 95% CI 0.83-1.13, P=0.68; OR=0.92, 95% CI 0.81-1.06, P=0.24, respectively). In subgroup analysis, none of the subtypes of JIA including systemic, rheumatoid factor (RF)-positive polyarticular, RF-negative polyarticular, and oligoarticular was not significantly associated with IL-10 polymorphism. Meta-analysis of the IL-10 haplotype revealed no association between GCC, ACC, and ATA haplotypes and JIA.

CONCLUSIONS

This meta-analysis showed that IL-10 polymorphisms were not associated with risk of JIA.

High Interleukin-10 Expression in Type 2 T Helper Cells in Septic Patients

Interleukin (IL)-10 response is associated with mortality in patients with sepsis. IL-10 is primarily produced by monocytes and type 2 T helper (Th2) cells. The aim of this study was to investigate differences in IL-10 production between monocytes and Th2 cells in patients with sepsis. Forty patients with sepsis and 35 healthy controls were enrolled. Cytokine expressions in peripheral blood mononuclear cells (PBMCs) were measured by flow cytometry. The IL-10 expression in the Th2 cells of the septic patients was higher than in the healthy controls, but the expression of IL-10 in the monocytes of the septic patients was lower than in the healthy controls. After regression analysis, IL-10 expression in Th2 cells was positively associated with sepsis, but IL-10 expression in monocytes was not associated with sepsis or shock. In conclusion, the production of IL-10 in Th2 cells was higher in the patients with sepsis.

Genetic association between TNF-α -857 C/T polymorphism and ankylosing spondylitis susceptibility: evidence from a meta-analysis

Certain studies have suggested that the tumor necrosis factor-α (TNF-α) −857 C/T polymorphism is associated with risk of ankylosing spondylitis. However, the conclusions remain controversial. Therefore, we performed a meta-analysis to provide a more precise conclusion. Such databases as PubMed, Embase, CBM, CNKI, and Wanfang Data were searched to identify relevant studies up to August 26, 2015. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the association between TNF-α −857 C/T polymorphism and ankylosing spondylitis susceptibility. A total of 10 studies were included in the meta-analysis. Overall, an elevated risk between TNF-α −857 C/T polymorphism and ankylosing spondylitis was observed in three genetic model (T vs. C: OR 1.86, 95% CI 1.19–2.92; CT vs. CC: OR 2.51, 95% CI 1.49–4.23; TT + CT vs. CC: OR 2.46, 95% CI 1.40–4.30), except in homozygote model (TT vs. CC: OR 2.41, 95% CI 0.96–6.06) and recessive model (TT vs. CT + CC: OR 1.54, 95% CI 0.71–3.35). Sensitivity analysis showed the overall results were robust. Subgroup analyses according to Hardy–Weinberg equilibrium and ethnicity showed that the increased risk of ankylosing spondylitis were predominant in Asian population. This meta-analysis indicated that TNF-α −857 C/T polymorphism might increase the susceptibility of ankylosing spondylitis, especially in Asians. Further studies were needed to verify the conclusion.