系统性红斑狼疮患者Fas和CD40L表达的初步研究
作者：徐红星, 邱德华,王慧娟 ,杨晓帆,季晓辉
【摘要】 目的 探讨系统性红斑狼疮(SLE)患者凋亡调节蛋白受体Fas及共刺激分子CD40L的表达情况及其相互之间的调节。方法 采用酶联免疫吸附试验(ELISA)检测SLE患者和正常人血清sFas和sCD40L的水平并分析两者之间的相关性;同时分离10例SLE患者和10例正常对照的外周血淋巴细胞：①将细胞培养48 h后，采用流式细胞仪检测T细胞亚群表面Fas及CD40L的表达情况;②在培养过程中分别加入抗FasL抗体阻断Fas信号及抗CD40L抗体阻断CD40L信号后，观察T细胞亚群表面CD40L及Fas的表达。结果 ①SLE患者血清sFas和sCD40L平均水平分别为4.18 μg/L和5.87 μg/L，显著高于正常对照组2.27 μg/L和2.31 μg/L,且SLE患者血清sFas活动期高于稳定期(P<0.01或P<0.05);sFas、sCD40L水平与SLEDAI(疾病活动指数)之间存在一定的正相关性(r=0.688,r=0.253，P均<0.05),但sFas与sCD40L水平之间未显示明显相关(r=0.201，P>0.05)。②经细胞培养后，SLE患者CD4(+)和CD8(+) T细胞表面Fas表达增加，与正常对照组比较，差异有显著性(P<0.01或P<0.05);SLE患者CD4(+)和CD8(+) T细胞表面CD40L表达增加，与正常对照组比较，差异有显著性(P均<0.05)。③SLE患者CD4(+)及CD8(+) T细胞上Fas与CD40L表达均呈正相关关系(r=0.311和r=0.517，P均<0.05)。④加入抗FasL抗体阻断后，CD4(+)和CD8(+) T细胞表面CD40L表达下降，与阻断前比较，差异有显著性(P<0.05);加入抗CD40L抗体阻断后，CD4(+)和CD8(+) T细胞表面Fas表达与阻断前比较差异无显著性(P>0.05)。结论 SLE患者血清sFas和sCD40L水平升高且呈正相关关系;T细胞亚群表面Fas及CD40L高表达且呈正相关关系;T细胞上Fas的表达调控CD40L的表达。说明凋亡调节蛋白Fas及共刺激分子CD40L可能共同参与SLE的发病过程。
【关键词】 系统性红斑狼疮;Fas;CD40L
Abstract: Objective To investigate the expressions of Fas and CD40L in patients with systemic lupus erythematosus (SLE). Methods Serum sFas, sCD40L levels in patients with SLE and healthy controls were determined using a commercially available ELISA system and the correlation between the levels of sFas and sCD40L was analyzed. Meanwhile, peripheral blood mononuclear cells (PBMC) of patients with SLE and health controls were isolated by gradient centrifugation of heparinized blood. The expressions of Fas and CD40L on CD4(+) and CD8(+) T lymphocytes in patients with SLE and controls were determined by flow cytometry (FCM) after cultivation for 48 h. The antibodies of FasL and CD40L were add in the process of cultivation, and then the expressions of CD40L and Fas of peripheral blood T lymphocytes were determined. Results ①The average levels of sFas and sCD40L in SLE patients were 4.18 μg/L and 5.87 μg/L, respectively, which were markedly higher than those of 2.27 μg/L and 2.31 μg/L in the healthy controls; the serum levels of sFas and sCD40L were significantly higher in active SLE patients than those inactive patients (P<0.01, P<0.05); the serum levels of sFas and sCD40L were shown to have a positive correlation with SLEDAI scores (r=0.688, r=0.253,P<0.05), while no positive correlation was revealed between the levels of sFas and sCD40L (r=0.201,P>0.05). ②The expressions of Fas on CD4(+) and CD8(+) T lymphocytes in patients with SLE were significantly higher than those of the healthy controls (P<0.01 and P<0.05); the expressions of CD40L on CD4(+) and CD8(+) T lymphocytes in patients with SLE were significantly higher than that of the healthy controls (P<0.05). ③There was no correlations between the expressions of Fas on CD4(+) and CD8(+) T lymphocytes and those of CD40L (r=0.311, r=0.517). ④The expressions of CD40L on CD4(+) and CD8(+) T lymphocytes in patients with SLE significantly decreased after blockage by the antibody of FasL (P<0.05); there was no difference in the expression of Fas in patients with SLE after blockage by the antibody of CD40L (P>0.05). Conclusion The levels of sFas and sCD40L in SLE patients were higher than those of healthy controls and there was a positive correlation between them. The expressions of Fas and CD40L on CD4(+) and CD8(+) T lymphocytes in patients with SLE increased; and the expression of Fas had a positive correlation with that of CD40L; meanwhile, the expression of Fas regulated that of CD40L, which suggests that both Fas and CD40L are involed in the process of SLE.
Key words：systemic lupus erythematosus; Fas; CD40L