Association of increased frequencies of HLA-DPB1*05:01 with the presence of anti-Ro/SS-A and anti-La/SS-B antibodies in Japanese rheumatoid arthritis and systemic lupus erythematosus patients.

INTRODUCTION

Autoantibodies to ribonucleoprotein are associated with a variety of autoimmune diseases, including rheumatoid arthritis (RA). Many studies on associations between human leukocyte antigen (HLA) alleles and RA have been reported, but few have been validated in RA subpopulations with anti-La/SS-B or anti-Ro/SS-A antibodies. Here, we investigated associations of HLA class II alleles with the presence of anti-Ro/SS-A or anti-La/SS-B antibodies in RA.

METHODS

An association study was conducted for HLA-DRB1, DQB1, and DPB1 in Japanese RA and systemic lupus erythematosus (SLE) patients that were positive or negative for anti-Ro/SS-A and/or anti-La/SS-B antibodies.

RESULTS

An increased prevalence of certain class II alleles was associated with the presence of anti-Ro/SS-A antibodies as follows: DRB1*08:03 (Pc = 3.79×10(-5), odds ratio [OR] 3.06, 95% confidence interval [CI] 1.98-4.73), DQB1*06:01 (Pc = 0.0106, OR 1.70, 95%CI 1.26-2.31), and DPB1*05:01 (Pc = 0.0040, OR 1.55, 95%CI 1.23-1.96). On the other hand, DRB1*15:01 (Pc = 0.0470, OR 3.14, 95%CI 1.63-6.05), DQB1*06:02 (Pc = 0.0252, OR 3.14, 95%CI 1.63-6.05), and DPB1*05:01 (Pc = 0.0069, OR 2.27, 95% CI 1.44-3.57) were associated with anti-La/SS-B antibodies. The DPB1*05:01 allele was associated with anti-Ro/SS-A (Pc = 0.0408, OR 1.69, 95% CI 1.19-2.41) and anti-La/SS-B antibodies (Pc = 2.48×10(-5), OR 3.31, 95%CI 2.02-5.43) in SLE patients.

CONCLUSION

HLA-DPB1*05:01 was the only allele associated with the presence of both anti-Ro/SS-A and anti-La/SS-B antibodies in Japanese RA and SLE patients.