Association Study of IL-12B Polymorphisms Susceptibility with Ankylosing Spondylitis in Mainland Han Population

Aberrant Methylation of miR-34b and IL-12B mRNA Promoters Contributes to the Reduced Severity of Ankylosing Spondylitis

DNA methylation of Interleukin-12B (IL-12B) and miR-34b was proved to affect the expression of IL-12B and miR-34b, which were found to be involved in the pathogenesis of ankylosing spondylitis (AS). However, the molecular mechanisms underlying the role of IL-12B and miR-34b in AS remain to be explored. AS patients were divided into four groups according to their status of DNA methylation of miR-34b and IL-12B by bisulfite sequencing: HYPER-miR-34b + HYPO-IL-12B, HYPER-miR-34b + HYPER-IL-12B, HYPO-miR-34b + HYPER-IL-12B and HYPO-miR-34b + HYPO-IL-12B groups. Functional indicators were examined for patients with different status of DNA methylation in their miR-34b and IL-12B promoters. QPCR was performed to examine the expression of miR-34b and IL-12B mRNA under different conditions. ELISA was used to measure the expression of IL-12B p40 in the peripheral blood. Western blot was used to analyze the expression of IL-12B proteins. Luciferase assay was carried out to explore the suppressive role of miR-34b in IL-12B expression. The level of Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP) was gradually increased in HYPER-miR-34b + HYPO-IL-12B,HYPER-miR-34b + HYPER-IL-12B,HYPO-miR-34b + HYPER-IL-12B and HYPO-miR-34b + HYPO-IL-12B groups, whereas the levels of Bath Ankylosing Spondylitis Functional Index (BASFI) and Bath Ankylosing Spondylitis Metrology Index (BASMI) were significantly elevated in the HYPO-miR-34b + HYPO-IL-12B group and diminished in the HYPER-miR-34b + HYPO-IL-12B group. The expression of miR-34b in the PBMCs and peripheral blood was remarkably higher in the HYPER-miR-34b + HYPO-IL-12B and HYPER-miR-34b + HYPER-IL-12B groups, whereas the expression of IL-12B was gradually decreased in the HYPER-miR-34b + HYPO-IL-12B, HYPER-miR-34b + HYPER-IL-12B, HYPO-miR-34b + HYPER-IL-12B and HYPO-miR-34b + HYPO-IL-12B groups. Luciferase assays with the transfection of miR-34b precursors suggested that miR-34b strongly suppressed the expression of IL-12B in THP-1 cells. In conclusion, our study demonstrated that hypermethylated miR-34b promoter led to evident upregulation of miR-34b, thus inhibiting the expression of IL-12B and alleviated the severity of ankylosing spondylitis by reducing the levels of factors including ASDAS-CRP, BASFI and BASMI.

Gut Microbiome and Its Interaction with Immune System in Spondyloarthritis

Emerging evidence suggests there is a gut-joint axis in spondyloarthritis (SpA). In a study, subclinical gut inflammation occurred in nearly 50% of SpA. Chronic gut inflammation also correlated with disease activity in SpA. Trillions of microorganisms reside in the human gut and interact with the human immune system. Dysbiosis affects gut immune homeostasis and triggers different autoimmune diseases including SpA. The absence of arthritis in HLA-B27 germ-free mice and the development of arthritis after the introduction of commensal bacteria to HLA-B27 germ-free mice proved to be the important role of gut bacteria in shaping SpA, other than the genetic factor. The recent advance in gene sequencing technology promotes the identification of microorganisms. In this review, we highlighted current evidence supporting the link between gut and axial SpA (axSpA). We also summarized available findings of gut microbiota and its interaction with the immune system in axSpA. Future research may explore the way to modulate gut microorganisms in axSpA and bring gut microbiome discoveries towards application.

Targeting inflammatory pathways in axial spondyloarthritis

The triggers and pathogenesis of axial spondyloarthritis (axSpA) are not yet completely understood. However, therapeutic agents targeting tumor necrosis factor-α and interleukin-17 inflammatory pathways have proven successful in suppressing many of the clinical symptoms and signs of axSpA, giving us an indication of which pathways are responsible for initiating and maintaining the inflammation. The mechanisms that eventuate in syndesmophytes and ankyloses are less clear. This review addresses these two critical pathways of inflammation, discussing their nature and these factors that may activate or enhance the pathways in patients with axSpA. In addition, genetic and other markers important to the inflammatory pathways implicated in axSpA are explored, and prognostic biomarkers are discussed. Treatment options available for the management of axSpA and their associated targets are highlighted.

Ankylosing spondylitis: analysis of gene-gene interactions between IL-12β, JAK2, and STAT3 in Han Chinese and Algerian cohorts

Introduction

Association studies have recently identified the importance of new genetic variants for ankylosing spondylitis (AS) in several populations. Our aim was to confirm associations of variants within genes involved in the IL-23 signalling pathway with AS in two ethnically different populations: Han Chinese and Algerian.

Material and methods

Two case-control studies were performed in separate cohorts: Han Chinese (430 AS patients and 580 controls) and Algerian (130 AS patients and 120 controls). We genotyped four single nucleotide polymorphisms (SNPs): rs3212227 (or +1188A/C) and rs6887695 in IL-12β, rs7857730 in JAK2, and rs2293152 in STAT3, using TaqMan SNP genotyping assays. Gene-gene interaction analyses were also tested by logistic regression and multifactor dimensionality reduction (MDR).

Results

Statistical analysis revealed a difference in allele frequencies between AS patients and controls for rs321222 in the IL-12β gene in both the Han Chinese (p = 0.005) and the Algerian (p = 0.031) cohorts. Two other associations were reported with JAK2 rs7857730 in the Han Chinese (allelic p = 0.014) cohort and STAT3 rs2293152 in the Algerian (allelic p = 0.006) cohort. Moreover, logistic regression analyses showed a number of significant combinations within the two populations, and the gene-gene epistasis effects in AS were also confirmed by MDR.

Conclusions

Our findings have confirmed the association between genes in IL-23 signalling pathway and the pathogenesis of AS. This association was particularly novel in both Han Chinese and Algerian populations with the 3’ untranslated region (3’UTR) variant rs3212227 (or +1188A/C) of IL-12β. The gene-gene interaction models in this pathway may thus increase the risk of AS in these populations.

Association of TNF, IL12, and IL23 gene polymorphisms and psoriatic arthritis: meta-analysis

BACKGROUND

Psoriatic arthritis (PsA) is a chronic skin and joint condition that considerably affects patient quality of life. Several studies have demonstrated different associations of genetic polymorphisms in the pathogenic process of PsA. Therefore, we conducted a meta-analysis to estimate the effect of polymorphisms in the cytokines TNF, IL12B, IL23A, and IL23R on PsA risk.

METHODS

We screened 1,097 abstracts and identified 14 relevant studies published between January 2007 and December 2017. A systematic search was conducted in PubMed, Web of Knowledge and Scopus databases. Meta-analyses were performed for the comparisons of alleles and multiple genetic models.

RESULTS

Among the cytokines studied, we found 17 polymorphisms that were the most investigated. The association to PsA was observed in the presence of polymorphisms: TNF-238 G > A (rs361525), -308 G > A (rs1800629), and -857 C > T (rs1799724); IL12B C > G (rs6887695) and A > C (rs3212227); IL23A A > G (rs2066808) and IL23R G > A (rs11209026).

CONCLUSION

Our findings suggest that these variant cytokine genes may strongly influence the immunological response of PsA.

Genetic variations in the IL-12B gene in association with IL-23 and IL-12p40 serum levels in ankylosing spondylitis

In the present study, we evaluated the implication of IL12Bpro (rs17860508) and IL12B 3' UTR A/C single nucleotide polymorphisms (SNPs) (rs3212227) for the ankylosing spondylitis (AS) development and the impact of IL12B genetic variations on IL-23 and IL-12p40 production and musculoskeletal disease characteristics. 80 patients with AS and 242 healthy controls were studied. Genotyping for the rs3212227 was performed by restriction fragment length polymorphisms-polymerase chain reaction (PCR) and for the rs17860508 by allele-specific PCR. Cytokines were measured by an enzyme-linked immunosorbent assay (ELISA). Clinical status was evaluated by calculation of the Ankylosing Spondylitis Disease Activity Score (ASDAS) using the C-reactive protein (CRP) level, the Bath Ankylosing Spondylitis Functional Index (BASFI) and the Bath Ankylosing Spondylitis Metrology Index (BASMI). An association was found for the rs17860508 polymorphism with AS under the allelic, the dominant, and the co-dominant models. Rs3212227 was not attributable to AS susceptibility by itself, but the carriage of C allele in the genotype amplifies the genetic risk for AS in the carriers of the high-risk IL12Bpro 2-allele, especially in homozygosity. Circulating IL-23 and IL-12p40 were raised among AS patients, as some of the genotypes of both IL12B polymorphisms positively regulate their expression. Carriage of the IL12Bpro genotype 2.2 has been linked to a worsened functional disability, while 3' UTR CC genotype-with severe disease activity. IL12B polymorphisms can impact AS susceptibility and modulate IL-23 and IL-12p40 production levels, and have a contribution to the disease phenotype.

The Diagnostic and Prognostic Role of Interleukin 12B and Interleukin 6R Gene Polymorphism in Patients With Ankylosing Spondylitis

OBJECTIVES

Interleukin 23 (IL-23) pathway and IL-1 cluster genes play prominent role in the etiopathology of ankylosing spondylitis (AS). The aim of this study was to investigate the diagnostic and prognostic role of 5 single-nucleotide polymorphisms related to IL-23 pathway and IL-1 cluster genes in AS patients.

METHODS

Four hundred thirty-one patients with AS and 206 age- and sex-matched healthy controls were recruited in this prospective cohort study. Five potential single-nucleotide polymorphisms (IL-23R [rs11209026], IL-12B [rs6871626], TYK2 [rs6511701], IL-6R [rs4129267], and IL-1R2 [rs2192752]) related to IL-23 pathway and IL-1 cluster genes by analyzing previous studies were genotyped. Among 431 total AS patients, 198 active cases were treated and followed up for 24 weeks.

RESULTS

Frequencies of IL-12B AA (rs6871626) and IL-6R TT (rs4129267) genotypes were increased in AS patients compared with healthy controls (both P < 0.001), and IL-12B A (rs6871626) as well as IL-6R T (rs4129267) allele increased the risk of AS independently (both P < 0.001). The Bath Ankylosing Spondylitis Disease Activity Index score was found to be elevated in AS patients with IL-12B AA (rs6871626) compared with patients with the CA and CC genotypes (P = 0.002 and P < 0.001, respectively), and the Bath Ankylosing Spondylitis Functional Index score was also increased in AS patents with IL-12B AA (rs6871626) than in those with the CA and CC genotypes (P = 0.001 and P < 0.001). In addition, IL-6R T (rs4129267) allele could predict a worse ASAS-20 (Assessment of SpondyloArthritis international Society) response at week 24 as an independent factor by multivariate logistic regression analysis with additive model (P = 0.011).

CONCLUSIONS

Interleukin 12B (rs6871626) and IL-6R (rs4129267) gene polymorphisms could serve as promising biomarkers for diagnosis and prognosis in AS patients.

IL1R1 polymorphisms are associated with ankylosing spondylitis in the Han Chinese population: a case-control study

Several studies have demonstrated that polymorphisms within the IL-1 gene cluster are associated with the risk of ankylosing spondylitis (AS) in different populations. In this study, we desired to know whether IL1R1, a gene located in the IL-1 gene cluster, is a susceptible gene for AS in a Northwest Chinese Han population. The Sequenom MassARRAY assay technique was used to determine the genotype of 267 AS patients and 297 controls from Northwest China. Genotype and allele distributions of the investigated IL1R1 variants (rs10490571, rs12712127, rs956730, rs3917225, and rs3917318) were compared among the cases and controls using Chi-square/Fisher's exact tests. In addition, the associations of these polymorphisms with AS risk were also assessed under dominant, recessive, and additive genetic models using PLINK software. We found the minor G allele of rs3917225 was associated with an increased risk of AS (OR=1.39, 95% CI: 1.09-1.77, P=0.007). Significant association was also detected for rs956730 under the dominant model (OR=0.54, 95% CI: 0.30-0.96, P=0.032) and the additive model (OR=0.55, 95% CI: 0.34-0.90, P=0.016), adjusting for age and gender. This study is the first to demonstrate the significant association between IL1R1 polymorphisms and AS susceptibility in a Northwest Chinese Han population.

Association of CD14 and macrophage migration inhibitory factor gene polymorphisms with inflammatory microRNAs expression levels in ankylosing spondylitis and polyarthralgia

This study aimed to investigate the genetic basis of ankylosing spondylitis (AS) and polyarthralgia (PA) conditions among Indian subjects through genotyping two immune regulatory genes CD14 (-159C>T) and MIF (-173G>C) and find their association with the expression levels of three circulating inflammatory miRNAs. This investigation may provide early genetic cause of these two forms of arthritis and more optimal biological targets to predict early therapeutic outcomes. A total of 140 patients (AS: 70 and PA: 70) and 156 controls were recruited from Indian population. CD14 and MIF genotyping was performed using ARMS-PCR. Expression level of three inflammatory miRNAs (miRNA-146a, miRNA-155 and miRNA-181) was quantified using RT-qPCR. C/T genotype of CD14 gene was found to cause 2.06-fold risk of developing AS (CI 1.06-5.98, p = .04) as compared to others and G/C genotype in MIF also shown significant variation between AS and control subjects. In PA subjects, CD14 genotypes (C/T) was found to be associated with disease susceptibility and G/C genotype of MIF gene polymorphism showed 4.71-fold risk of developing PA (CI 2.58-8.62, p = .0001). The study also revealed significant upregulation of miRNA-155 expression in AS subjects (p = .0001) with more than 1.3-fold difference between AS and PA as compared to the control subjects. miRNA-155 had strong association with AS patients with CD14 genotypes (p < .05) than PA and control subjects. This study provides better understanding of the mechanisms and disease susceptibility for MIF and CD14 genetic variants and inflammatory miRNAs networks involved in AS and PA.

INPP5D rs35349669 polymorphism with late-onset Alzheimer's disease: A replication study and meta-analysis

Inositol polyphosphate-5-phosphatase (INPP5D) was reported to be associated with Alzheimer's disease (AD) through modulating the inflammatory process and immune response. A recent genome-wide association study discovered a new locus single nucleotide polymorphism (SNP, rs35349669) of INPP5D which was significantly associated with susceptibility to late-onset Alzheimer's disease (LOAD) in Caucasians. In this study, we investigated the relations between the INPP5D polymorphism rs35349669 and LOAD in Han Chinese population comprising 984 LOAD cases and 1352 healthy controls being matched for age and gender. Our results showed no obvious differences in the genotypic or allelic distributions of rs35349669 polymorphism between LOAD cases and healthy controls (genotype: p = 0.167; allele: p = 0.094). Additionally, when these data were stratified by APOEε4 status, there are still no evident differences in the genotypic or allelic distributions in APOEε4 carriers (p > 0.05). Furthermore, meta-analysis of 81964 individuals confirmed that rs35349669 was significantly associated with the risk for LOAD (OR=1.08, 95%CI=1.06-1.11), but the results remained negative in Chinese subgroup (OR=0.77, 95%CI=0.53-1.13). Overall, the current evidence did not indicate that INPP5D rs35349669 polymorphism play a role in the genetic predisposition to LOAD in Chinese population.

A Variant in RUNX3 Is Associated with the Risk of Ankylosing Spondylitis in Koreans

Ankylosing spondylitis (AS) is a chronic autoinflammatory disease that affects the spine and sacroiliac joints. Regarding its etiology, although HLA-B27 is known to be the strongest genetic factor of AS, much evidence suggests the potential contribution of non-MHC genes to the susceptibility to AS. Most of these non-MHC genes have been discovered in non-Asian populations; however, just some of them have been validated in Koreans. In this study, we aimed to identify additional AS-associated single-nucleotide polymorphism (SNP) candidates by replicating the candidate SNPs in Korean AS patients and healthy controls. For this, we selected three SNPs (rs11249215 in RUNX3, rs6556416 in IL12B, and rs8070463 in TBKBP1), which were previously reported as risk factors of AS but have not been studied in Koreans, and performed genotyping assays using a total of 1138 Korean samples (572 AS patients and 566 healthy controls). Of the three SNP candidates, one SNP in RUNX3 (rs11249215) was significantly associated with the risk of AS (odds ratio, 1.31; 95% confidence interval, 1.02 to 1.68, p = 0.03). These results will be helpful in elucidating the pathogenesis of AS and may be useful for developing AS risk prediction models in Koreans.

Pathogenic variants screening in seventeen candidate genes on 2p15 for association with ankylosing spondylitis in a Han Chinese population

OBJECTIVES

Previous studies have found the association between rs10865331 in 2p15 area and ankylosing spondylitis (AS). This study aimed to identify additional functional genetic variants in 2p15 region associated with AS susceptibility.

METHODS

We used next generation sequencing (NGS) in 100 AS cases and 100 healthy controls to screen AS susceptible genetic variants, and validated these variants in 620 cases and 620 controls by using imLDRTM technique for single nucleotide polymorphism (SNP) genotyping.

RESULTS

Totally, we identified 12 SNPs that might confer susceptibility to AS. Of those SNPs, three (rs14170, rs2123111 and rs1729674) were nominally associated (P<0.05) with AS, but were no longer statistically significant after Bonferroni correction. After stratified by gender, another two SNPs (rs11428092 and rs10208769 in USP34) were associated with AS in males but not females, though this was not statistically significant after Bonferroni correction. In addition, rs1729674, rs14170, rs2123111 and rs10208769 were in strong linkage disequilibrium (LD) and were further enrolled in haplotype analysis. A novel haplotype TAGA was found to be associated with a decreased risk of AS (odds ratio (OR) (95% confidence interval (CI)) = 0.832 (0.705-0.982)). Beyond that, we also demonstrated a strong relationship between rs10865331 and AS susceptibility (OR (95% CI) = 1.303(1.111-1.526)).

CONCLUSIONS

rs14170 and rs2123111 inUSP34 and rs1729674 in C2orf74 may be associated with AS susceptibility in Han Chinese population. USP34 and C2orf74 in 2p15 region may be AS novel susceptibility genes.

Analysis of the common genetic component of large-vessel vasculitides through a meta-Immunochip strategy

Giant cell arteritis (GCA) and Takayasu’s arteritis (TAK) are major forms of large-vessel vasculitis (LVV) that share clinical features. To evaluate their genetic similarities, we analysed Immunochip genotyping data from 1,434 LVV patients and 3,814 unaffected controls. Genetic pleiotropy was also estimated. The HLA region harboured the main disease-specific associations. GCA was mostly associated with class II genes (HLA-DRB1/HLA-DQA1) whereas TAK was mostly associated with class I genes (HLA-B/MICA). Both the statistical significance and effect size of the HLA signals were considerably reduced in the cross-disease meta-analysis in comparison with the analysis of GCA and TAK separately. Consequently, no significant genetic correlation between these two diseases was observed when HLA variants were tested. Outside the HLA region, only one polymorphism located nearby the IL12B gene surpassed the study-wide significance threshold in the meta-analysis of the discovery datasets (rs755374, P = 7.54E-07; OR_GCA = 1.19, OR_TAK = 1.50). This marker was confirmed as novel GCA risk factor using four additional cohorts (P_GCA = 5.52E-04, OR_GCA = 1.16). Taken together, our results provide evidence of strong genetic differences between GCA and TAK in the HLA. Outside this region, common susceptibility factors were suggested, especially within the IL12B locus.

Single nucleotide polymorphisms of IL12B are associated with Takayasu arteritis in Chinese Han population

Takayasu arteritis (TA) is a rare autoimmune disease of unknown etiology. Genome-wide association studies (GWAS) have demonstrated association between genetic variants of IL12B and IL6 and TA. Since TA has been reported with ethnic heterogeneity, we sought to investigate whether the single-nucleotide-polymorphisms (SNPs) reported in these studies are associated with TA in the Chinese Han population. A multi-center study involving 412 patients with TA and 597 healthy controls was conducted. Sequenom MassArray iPLEX platform was used to determine the frequencies of SNPs in the IL12B and IL6 region. We demonstrated a allele association between the four SNPs of IL12B and TA (rs6871626: OR 1.52, 95% CI 1.26-1.83; rs4921492: OR 1.46, 95% CI 1.21-1.75; rs60689680: OR 1.41, 95% CI 1.17-1.69; rs4921493: OR 1.45, 95% CI 1.21-1.75, all P _c  < 10^- 3 ). A meta-analysis consist of four populations showed rs6871626 was a susceptible locus of TA. Its OR was 1.51, and 95% CI was 1.31-1.74. The four SNPs were in strong linkage disequilibrium and two haplotypes were significantly different between patients and controls. Conditional analysis shows that these SNPs were not independent factors contributing to TA. Nevertheless, neither genotype nor allele frequencies of rs2069837 in IL6 showed significant between-group differences. Thus SNP of IL12B may be considered a high-risk factor for TA in Chinese Han population and provide further clues for research into the pathogenesis of TA.

Genetic Variants in IL-12B and IL-27 in the Polish Patients with Systemic Lupus Erythematosus

To investigate the potential association between IL-12B and IL-27 gene polymorphisms and systemic lupus erythematosus (SLE), we performed a case-control study based on the Polish population. Patients with SLE and healthy individuals were examined for -6415 CTCTAA/GC (rs17860508) and +1188A/C (rs3212227) in IL-12B and -924A/G (rs153109) and 4730T/C (rs181206) in IL-27 gene polymorphisms using the high-resolution melting method, PCR-RFLP method and TaqMan SNP genotyping assay, respectively. An increased frequency of GC/GC genotype as well as GC allele of the IL-12B rs17860508 was found in patients with SLE, as compared with healthy subjects (P < 0.001). We did not find differences in genotype and allele frequencies of the IL-12B rs3212227 and IL-27 rs153109 and rs181206 variants between patients with SLE and controls. IL-27 haplotype rs181206C/rs153109G indicated higher risk for SLE (P = 0.002), whereas haplotype rs181206T/rs153109G indicated reduced risk for SLE (P = 0.005). The IL-12B rs3212227 A/C polymorphism was associated with the mean value of the platelets (PLT), urea and complement C3 level. Furthermore, IL-12B rs17860508 genetic variant showed correlation with PLT, prothrombin time, international normalized ratio and alkaline phosphatase. Our results revealed that IL-12B rs17860508 and IL-27 haplotype CG are genetic risk factors for SLE and that both IL-12B rs17860508 and rs3212227 predict disease phenotype.

Genetic analysis of TNFST15 variants in ankylosing spondylitis

AIMS

The purpose of this study was to explore the role of TNF-like ligand 1A (TL1A) gene (TNFST15) polymorphisms (rs3810936, rs7848647, and rs6478109) in the generation of ankylosing spondylitis (AS).

METHODS

Polymerase chain reaction (PCR) and sequencing were used to conduct the genotyping of TNFSF15 polymorphisms in 113 AS patients and 120 healthy persons as the case and control groups. The frequencies comparison was performed by chi-square or t test between the two groups. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated to represent the correlation between TNFSF15 polymorphism and AS. Besides, genotypes distribution of the former in controls was checked by Hardy-Weinberg equilibrium (HWE).

RESULTS

There was statistically significant difference in AS patients and controls based on family history. Among TNFSF15 polymorphisms, only TT genotype frequency of rs3810936 in cases was obviously high, compared with the controls (P=0.04), the results indicated that TT was a high-risk genotype (OR=2.31, 95% CI=1.03-5.20). However, both of rs6478109, rs7848647 polymorphisms didn't show any association with AS.

CONCLUSION

Rs3810936 of TNFSF15 were related to the risk of AS and we should pay more attention to the role of TNFSF15 polymorphisms in the pathogenesis of AS in the future.