B细胞激活因子与系统性红斑狼疮的相关性研究

目的从核酸(mRNA)和血清蛋白水平初步探讨B细胞激活因子(BlyS)在系统性红斑狼疮(SLE)发病中的作用机制。方法用自行建立的酶联免疫吸附测定法(ELISA)和荧光定量逆转录聚合酶链反应(FQRTPCR),对59例相对稳定期SLE患者和40名健康人血清BlyS含量、外周血单个核细胞(PBMC)中BlySmRNA含量进行检测;并比较SLE患者血清BlyS含量与外周血BlyS基因表达水平、免疫球蛋白(IgG、IgA、IgM)浓度和抗双链DNA(dsDNA)抗体滴度的相关性。结果59例相对稳定期SLE患者血清BlyS含量[(8.42±1.55)μg/L]明显高于健康对照组[(3.19±0.88)μg/L,P<0.001],并与IgG浓度、抗dsDNA抗体的滴度呈正相关性(分别r=0.442,r=0.850,均P<0.001)。与健康对照组相比,59例SLE患者中39例(66%)外周血BlyS基因水平明显升高(P<0.001),与血清BlyS含量呈明显正相关(r=0.652,P<0.001)。结论主要由BlyS基因异常表达所引发的高浓度BlyS血清蛋白是一明显的SLE免疫病理特征;BlyS作为SLE发病的重要调控因子,可能在自身反应性B细胞的活化和促进特异性自身抗体的产生中均发挥着重要作用。

Clinical preliminary assessment for B lymphocyte stimulator and systemic lupus erythematosus

Objective To investigate the relationship between B-lymphocyte stimulator (BlyS) and systemic lupus erythematosus (SLE) both at protein and mRNA level.Methods The circulating levels of BlyS and the specific gene expression of BlyS in 59 SLE patients were examined with the previous ELISA and FQ-RT-PCR assay.Serum samples from 59 patients with SLE were also assayed for quantitative immunoglobulins(IgG,IgA,IgM)and anti-double-stranded DNA(anti-dsDNA) antibody levels, and compared with samples from 40 healthy control subjects.Results Serum BlyS levels in 59 patients with SLE were significantly elevated (P<0.001) and correlated with the levels of IgG and the titers of anti-dsDNA antibody (r=0.442,r=0.85,P<0.001).More importantly, 66% (39/59) of these SLE patients had significantly higher level of blood BlyS mRNA, closely paralleled with serum BlyS levels (r=0.652,P<0.001).Conclusion Dysregulation of BlyS is relatively common in patients with SLE.Excessive serum BlyS production may result from overexpression of BlyS gene. BlyS might play an important part in activating specific autoreactive B cells and modulating the level of production of autoantibodies.