汉族类风湿关节炎患者HLA-DM和-DR基因的表达

Expression of HLA-DM and-DR gene in rheumatoid arthritis patients in the Han nationality

目的 探讨我国汉族类风湿关节炎 (RA)患者的人类白细胞抗原 (HLA) DM (DMA和DMB)基因的表达。方法 以 3 3名正常献血者及 2 6例强直性脊柱炎 (AS)患者为对照 ,应用半定量和竞争性逆转录 多聚酶链式反应 (RT PCR)检测 3 6例RA患者 ,用抗CD19单克隆抗体包被的磁珠从外周血中分离出B细胞的HLA DMA、 DMB及 DRB基因转录物的量。并应用Westernblot分析HLA DM和 DR的蛋白表达量。结果 与正常对照组或AS组相比 ,RA患者的HLA DMA和 DMB转录物的表达均明显降低 (P均 <0 0 1)。而与正常对照组相比 ,RA患者的DRB转录物的表达差异无显著性 (P >0 0 5 )。RA组的HLA DM/DR平均比值明显低于正常对照组 (P <0 0 1)。从蛋白质水平看 ,与正常对照组相比 ,RA患者的DMA/ β actin比值明显降低 (P <0 0 1) ,而DRA/ β actin 比值在两组间差异无显著性 (P >0 0 5 )。结论 RA患者的HLA DM基因的转录水平和蛋白质水平均有明显下降 。

Objective To investigate the expression of HLA DM (DMA and DMB) gene in patients with rheumatoid arthritis (RA) in the Han nationality.Methods HLA DMA, DMB and DRB transcripts in purified peripheral blood B cells with anti CD19 mAb coated magnetic beads from 36 RA patients,26 ankylosing spondylitis (AS) and 33 matched normal control subjects were analyzed by semiquantitative and competitive RT PCR.Meanwhile,the expression of HLA DM and DR proteins was also quantified by Western blot.Results Compared with normal controls or AS patients,only the transcription of HLA DMA and DMB from RA patients was significantly decreased ( P <0 01),but no difference in HLA DRB ( P >0 05).An mean DM∶DR ratio in RA patients was significantly lower than that in normal controls ( P <0 01).The mean ratio of DMA/β actin in RA patients was dramatically decreased compared with that in normal controls at protein level ( P <0 01),but DRA/β actin showed no significant difference between the two groups ( P >0 05).Conclusion This specific HLA DM down regulation might play an important role in the processes of antigen presentation and autoimmune in RA.