CD28/CTLA-4共刺激分子在实验性变态反应性脑脊髓炎发病机制中的作用

摘要

目的：研究CD28/CTLA-4共刺激分子在实验性变态反应性脑脊髓炎( EAE)发病机制中可能的免疫学作用。方法将60只成年雌性豚鼠随机分为3组各20只,分别为对照组、佐剂对照组及EAE模型组,流式细胞术检测各组外周血CD 4+T细胞膜上CD28、CTLA-4共刺激分子的表达,ELISA法检测外周血单个核细胞分泌INF-γ及IL-4的量,并评测两者比值的相关性。结果 EAE模型组豚鼠外周血CD 4+T细胞膜上CD28的表达率为(42．39±9．82)%,高于对照组及佐剂对照组,差异有统计学意义(P<0．05)；EAE模型组CTLA-4表达率为(2．31±1．27)%,低对照组及佐剂对照组,差异有统计学意义(P<0．05)；而对照组与佐剂对照组在CD28和CTLA-4两者的表达率上差异无统计学意义(P>0．05)。Pearson直线相关分析发现：CD28/CTLA-4比值与IFN-γ/IL-4比值呈正相关(r=0．645,P=0．000)。结论 EAE豚鼠外周血CD 4+T膜上CD28/CTLA-4共刺激分子表达失衡,并且影下游Th1/Th2的细胞因子分泌失衡,异常免疫反应持续增强,从而使EAE豚鼠发病。%Objective To study the CD28/CTLA-4 costimulatory molecules in the pathogenesis of experimental allergic encephalomyelitis( EAE) . Methods 60 adult female guinea pigs were randomly divided into 3 groups with 20 rats in each group, the normal control group,adjuvant control group and EAE model group were named. The percentage of CD28,CTLA-4 expressing on CD 4+T cells were detected by FACS and INF-γ,IL-4 secreted by PBMC were detected by ELISA. Results The percentage of CD28 in EAE model group was(42. 39 ± 9. 82)%,higher than that of normal control group and adjuvant control group,the differ-ence was statistically significant(P<0. 05);the percentage of CTLA-4 in EAE model group was(2. 31 ± 1. 27)%,lower than that of normal control group and adjuvant control group,the difference was statistically significant(P<0. 05);the normal control group and adjuvant control group in both the expression of CD28 and CTLA-4 rate were not statistically different(P>0. 05). Analysis of Pearson linear correlation discovery:CD28/CTLA-4 ratio and IFN-γ/IL-4 ratio was positively related(r=0. 645,P=0. 000). Con-clusion The imbalance of CD28/CTLA-4 costimulatory molecules and the downstream imbalance of Th1/Th2 were occurred in rats with EAE,Which results occurrence of the disease.