Association of HLA-G 3'UTR Polymorphisms with Soluble HLA-G Levels and Disease Activity in Patients with Rheumatoid Arthritis: A Case-Control Study

Background: Human leukocyte antigen (HLA)-G antigens are inducible non-classical major histocompatibility complex class Ib molecules which play an important role in the regulation of inflammatory processes and immunomodulation in autoimmune diseases. There are controversial reports on the impact of HLA-G gene polymorphisms on rheumatoid arthritis (RA). This study aimed at examining the impact of 14 base pair (bp) ins/del (rs66554220) and +3142G>C (rs1063320) polymorphisms and correlating these with soluble HLA-G (sHLA-G) levels to understand the susceptibility to RA in our sample cohort. Methods: Genomic DNA from 140 RA patients and 125 healthy controls was isolated using the salting out method. The genotyping of two polymorphisms of HLA-G (+3142G>C and 14 bp ins/del) was done by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and PCR method, respectively. Levels of sHLA-G were estimated by ELISA and disease activity was calculated by disease activity score (DAS28-ESR). Results: The HLA-G +3142G>C polymorphism was found to be associated with a decreased risk of RA as attributed to recessive inheritance tested model results (OR = 0.4, 95%C.I. = 0.2-0.9, p = .0313*, GG + GC versus CC). Our finding did not support an association between HLA-G 14 bp ins/del variant and risk/protection of RA. The sHLA-G levels were significantly lower in +3142GG and +3142GC RA patients as compared to healthy controls. Conclusion: HLA-G +3142G>C gene polymorphism might decrease the risk of occurrence of RA in our sample cohort as +3142CC genotype is associated with increased sHLA-G levels. Abbreviations: HLA-G: human leukocyte antigen-G; RA: rheumatoid arthritis; MHC: major histocompatibility complex; UTR: untranslated region; URR: upstream regulatory region; SLE: systemic lupus erythematous; PCR-RFLP: polymerase chain reaction restriction fragment length polymorphism; sHLA-G: soluble HLA-G; bp: base pair; ACR/EULAR: American College of Rheumatology/European League against Rheumatism; RF: rheumatoid factor; Anti-CCP: anti-cyclic citrullinated peptide; DAS28-ESR: Disease Activity Score 28- Erythrocyte Sedimentation Rate; TJC: tender joint count; SJC: swollen joint count; ESR: erythrocyte sedimentation rate; PGA: patient global assessment; HTN: hypertension; DM: diabetes mellitus; TB: tuberculosis; IEC: Institute Ethics Committee; ELISA: enzyme linked immunosorbent assay; ROC: receiver operating characteristics; AUC: area under curve; SNP: single nucleotide polymorphism; MTX: methotrexate; DMARDs: disease modifying anti-rheumatic drugs; Treg: regulatory T cells; IL: interleukin Units: soluble HLA-G: Units/mL {U/mL

Immunogenetics of autoimmune diseases in Asian Indians

The HLA class II molecules play a critical role in the processing and presentation of specific peptides derived from autoantigens of pancreatic beta cells or gluten for T cell scrutiny in IDDM and CD. In the present study, extended DR3-positive haplotypes associated with autoimmunity in northern Indian patients have been reported. The haplotype A26-B8-DR3 was the most common autoimmunity-favoring haplotype encountered among these patients. This association is, indeed, unique to Indian autoimmune patients, as it replaces the otherwise most commonly associated Caucasian haplotype A1-B8-DR3 (AH8.1) in this population. Further, CD patients revealed 100% association with DQB1*0201 along with DQA*0501 (97%) either in cis or trans configuration

Genomic evaluation of HLA-DR3⁺haplotypes associated with type 1 diabetes

We have defined three sets of HLA-DR3+ haplotypes that provide maximum risk of type 1 disease development in Indians: (1) a diverse array of B8-DR3 haplotypes, (2) A33-B58-DR3 haplotype, and (3) A2-B50-DR3 occurring most predominantly in this population. Further analysis has revealed extensive diversity in B8-DR3 haplotypes, particularly at the HLA-A locus, in contrast to the single fixed HLA-A1-B8-DR3 haplotype (generally referred to as AH8.1) reported in Caucasians. However, the classical AH8.1 haplotype was rare and differed from the Caucasian counterpart at multiple loci. In our study, HLA-A26-B8-DR3 (AH8.2) was the most common B8-DR3 haplotype constituting >50% of the total B8-DR3 haplotypes. Further, A2-B8-DR3 contributed the maximum risk (RR = 48.7) of type 1 diabetes, followed by A2-B50-DR3 (RR = 9.4), A33-B58-DR3 (RR = 6.6), A24-B8-DR3 (RR = 4.5), and A26-B8-DR3 (RR = 4.2). Despite several differences, the disease-associated haplotypes in Indian and Caucasian populations share a frozen DR3-DQ2 block, suggesting a common ancestor from which multiple haplotypes evolved independently

Correction to: Improvements in cholesterol efux capacity of HDL and adiponectin contribute to mitigation in cardiovascular disease risk after bariatric surgery in a cohort with morbid obesity

An amendment to this paper has been published and can be accessed via the original article

HLA class II allele genetic propensity in Oral submucous fibrosis

Aim or Purpose: Oral Sub-Mucous Fibrosis (OSMF) is a premalignant condition that alters fibro elasticity of oral submucosa and predominantly confined to Southeast Asian region. Variability in clinical course is intriguing, a fraction of betel nut users develops OSMF (0.1-11%), while a majority show no signs and symptoms despite prolonged use; severe forms are associated with very short history of tobacco use. This inconsistency in disease association is indicative of genetic association, but specific role of genes in its susceptibility remains largely unidentified. The objective was to assess and compare HLA-DRB1, -DQB1, -DPB1 allele phenotype frequencies in OSMF patients and healthy controls. Materials and Methods: Patients aged 18-55 years were recruited and tobacco history was recorded followed by collection of blood sample for DNA extraction and quality check. HLA class II genotyping was performed using Next Generation Sequencing protocol for 154 samples with 119 OSMF patients and 35 controls. Data was analysed using sequencing software. Study was approved by Institute Ethics committee of AIIMS New Delhi and study duration was 18 months. Results: Mean age of patients was 42.23±11.98 years with mild (36.7%), moderate (36.7%) and severe (26.7%) OSMF patients. -DPB1*04 was observed as the most frequent allele (71.43%) followed by HLA-DQB1 *03 allele in 46.5% of the samples. HLA-DQB1 *04 was the least frequent allele present in 1.73% of the samples. Conclusions: Insights into potential predisposing or protective HLA allele help better characterize inter individual variations in immune responses in severity and progression of OSMF and develop potential genetic biomarker for screening and prognosis & reduce malignant transformation rate in OSMF

Synovial IL-9 facilitates neutrophil survival, function and differentiation of Th17 cells in rheumatoid arthritis

Abstract Background Role of Th9 cells and interleukin-9 (IL-9) in human autoimmune diseases such as psoriasis and ulcerative colitis has been explored only very recently. However, their involvement in human rheumatoid arthritis (RA) is not conclusive. Pathogenesis of RA is complex and involves various T cell subsets and neutrophils. Here, we aimed at understanding the impact of IL-9 on infiltrating immune cells and their eventual role in synovial inflammation in RA. Methods In vitro stimulation of T cells was performed by engagement of anti-CD3 and anti-CD28 monoclonal antibodies. Flow cytometry was employed for measuring intracellular cytokine, RORγt in T cells, evaluating apoptosis of neutrophils. ELISA was used for measuring soluble cytokine, Western blot analysis and confocal microscopy were used for STAT3 phosphorylation and nuclear translocation. Results We demonstrated synovial enrichment of Th9 cells and their positive correlation with disease activity (DAS28-ESR) in RA. Synovial IL-9 prolonged the survival of neutrophils, increased their matrix metalloprotienase-9 production and facilitated Th17 cell differentiation evidenced by induction of transcription factor RORγt and STAT3 phosphorylation. IL-9 also augmented the function of IFN-γ + and TNF-α + synovial T cells. Conclusions We provide evidences for critical role of IL-9 in disease pathogenesis and propose that targeting IL-9 may be an effective strategy to ameliorate synovial inflammation in RA. Inhibiting IL-9 may have wider impact on the production of pathogenic cytokines involved in autoimmune diseases including RA and may offer better control over the disease