Analysis of Gene Expression of Human Leukocyte Antigen B27 in Patients with Ankylosing Spondylitis and Correlation with Related Indicators

Abstract

The aim of this study was to investigate the potential correlation between the human leukocyte antigen (HLA)-B*27 subtypes in patients with ankylosing spondylitis (AS) and the clinical features of AS. The prevalence of HLA-B*27 subtypes was investigated in 132 healthy donors recruited from our center and in 143 patients with AS. We investigated the differences in HLA-B27 subtype status for the patients and healthy donors by using a PCR-SSP (polymerase chain reaction with sequence-specific primer) method. The clinical outcomes of the patients, including lower back pain, uveitis, peripheral arthritis, stiffness, joints, erythrocyte sedimentation rate (ESR), Anti-streptolysin O (ASO) and C-reactive protein (CRP), were recorded. The male-to-female ratio was 2.5, and the mean age at diagnosis was 29.3 years. HLA-B*27 positivity was detected in 111 patients (77.6%) of patients with AS. The rate of HLA-B*27 positivity was significantly higher in the AS group than patients without AS. The subtypes observed in patients with AS were HLA-B*2704 (55.9%, 62/111), HLA-B*2705 (39.6%, 44/111), HLA-B*2702 (1.80%, 2/111), HLA-B*2707 (0.90%, 1/111), and HLA-B*2704/05(1.80%, 2/111). The main genotypes were HLA-B*2704 and HLA-B*2705. There were no significant differences in clinical manifestations. Multivariate analysis showed statistically significant differences in sex (P=0.01), disease duration (P=0.023), hematocrit (P=0.01), and CRP (P=0.01) between patients in the HLA-B*27(+) AS group and the HLA-B*27(-) AS group. In addition, HLA-B*15, HLA-B*40, HLA-B*13, and HLA-B*46 were the major alleles with associated HLA-B types in patients with HLA-B*27(+) AS. Therefore, we conclude that HLA-B*27 is highly correlated with AS and can be used as an early predictor of AS. In addition, sex, disease duration, ESR, and CRP were significantly different in the HLA-B*27(+) AS group and HLA-B*27(-) AS group. Finally, our study also found a correlation between HLA-B*15, HLA-B*40, HLA-B*13, and HLA-B*46 subtypes and the development of AS.