类风湿关节炎患者外周血CD4+T细胞凋亡及其相关信号蛋白表达的检测和临床意义

目的探讨CD4~＋T细胞凋亡在类风湿关节炎（rheumatoid arthritis,RA）发病机制中的作用及其凋亡机制。方法应用流式细胞术分析类风湿关节炎患者及健康对照组外周血CD4~＋T细胞凋亡指标AnnexinV水平及凋亡相关信号蛋白Caspase-3,Caspase-8,促凋亡基因Fas和抑凋亡基因Bcl-2表达水平;同时对CD4~＋T细胞凋亡相关信号蛋白ESR、RF和DAS 28水平与临床活动相关指标进行相关性分析。结果与健康对照组相比,RA活动期患者CD4~＋T细胞数增加（40.91±2.73）%vs（31.40±2.71）%,P〈0.05],CD4~＋T cell凋亡指标AnnexinV水平减少（2.27±1.43）%vs（8.10±2.06）%,P〈0.05];RA患者外周血中CD4~＋T细胞促凋亡基因Fas表达较健康对照组降低差异无统计学意义（63.12±4.61）%vs（84.13±1.72）%,P〈0.01],抑凋亡基因Bcl-2表达增加（93.58±2.36）%vs（75.14±5.70）%,P〈0.05],Caspase-8减少（18.54±15.23）%vs（3.02±1.39）%,P〈0.05],Caspase-3表达无差异无统计学意义（2.17±1.19）%vs（2.53±1.46）%,P〉0.05];CD4~＋T细胞促凋亡基因Fas表达与DAS28评分呈负相关（r=-0.89,P=0.04,P〈0.05）,Bcl-2与DAS28评分呈正相关（r=-0.97,P=0.00,P〈0.01）。结论RA患者CD4~＋T细胞数量增多与其凋亡减少有关,这可能是导致该病自身免疫反应不能控制的重要原因之一。RA患者外周血CD4~＋T细胞凋亡减少与促凋亡基因Fas表达降低、凋亡相关蛋白Caspase-8表达下降及抑凋亡基因Bcl-2表达增高有关。Fas和Bcl-2的表达可作为评价临床活动性的敏感指标。

Reduced apoptosis of CD4+T cells and expression of apoptosis-related signal proteins in patients with rheumatoid arthritis

Objective To investigate the apoptosis of CD4~+T cells and the expression of apoptosis-related signal proteins in patients with rheumatoid arthritis(RA).Methods The expression levels of Annexin V,Caspase-3,Caspase-8,Fas and Bcl-2 of CD4~+T lymphocytes in patients with RA and control individuals were measured by using flow cytometry.The correlation between the expression of apoptosis signaling proteins and clinical activity parameters ESR,CPR,RF and DAS28 were analyzed. Results The level of CD4~+T lymphocytes in RA patients was significantly higher than that in control individuals(40.91±2.73)%vs(31.40±2.71)%,P<0.05],while the value of AnnexinⅤ/ CD4~+T was lower(2.27±1.43)%vs(8.10±2.06)%,P<0.05]that of control individuals. Compared with the control individuals,the expression rate of Fas in CD4~+T cells of RA patients was significantly decreased in the active phases(63.12±4.61)%vs(84.13±1.72)%,P<0.01],the expression of Bcl-2 was significantly increased(93.58±2.36)%vs(75.14±5.70)%,P<0.05], the expression of Caspase-8 was decreased(18.54±15.23)%vs(3.02±1.39)%,P<0.05],but there was no statistical significance in Caspase3 expression between two groups(2.17±1.19)%vs (2.53±1.46)%,P>0.05].The expression of Fas on CD4~+T cells was negatively correlated with DAS28 parameter(r=-0.89,P=0.04,P<0.05),whereas Bcl-2 was positively correlated with DAS28 parameter(r=-0.97,P=0.00,P<0.01).Conclusion In RA patients,the increased expression of CD4~+T cells and the decreased expression of AnnexinⅤmight be associated with the decreased apoptosis rate,which may be involved in the pathogenesis of RA.The expression of Fas and Bcl-2 in CD4~+T cells of RA patients might be a sensitive indicator for the clinical activity of RA.