CD28+/CD152+:B7协同刺激分子在重症肺炎免疫紊乱发病机制中的作用研究

目的 研究CD28+/CD152+:B7协同刺激分子在重症肺炎免疫紊乱发病机制中的可能作用.方法 以流式细胞术分析22例重症肺炎外周血中CD3+T细胞上CD28+、CD152+表达及CD14+单核细胞上的CD86+、HLA-DR+表达.评价CD28+、CD152+、CD86+与HLA-DR+相关性;APACHE Ⅱ评分和CD28+、CD152+、CD86+、HLA-DR+表达的相关性.结果 重症肺炎病人入院24 h内CD3+T细胞及CD86+,HLA-DR+表达较正常对照组显著减少(P＜0.05);CD28+、CD152+表达较正常对照组显著增加(P＜0.05);CD8+CD3+、CD4+ CD3+阳性的T细胞无显著变化(P＞0.05).存活组重症肺炎入院第10天和第1天比较APACHE Ⅱ评分显著减少(P＜0.01);CD28+、CD152+、CD86+、HLA-DR+表达显著升高(P＜0.05);CD3++T细胞也显著增加(P＜0.05);CD8+ CD3+,CD4+ CD3+阳性的T细胞无显著变化(P＞0.05).重症肺炎协同刺激分子CD28+与HLA-DR+无显著相关(r=-0.12,P＞0.05),与APACHE Ⅱ评分无相关(r=-0.30,P＞0.05);协同刺激分子CD152+与HLA-DR+呈正相关(r=0.61,P＜0.01),与APACHE Ⅱ评分无相关(r=0.15,P＞0.05);协同刺激分子CD86+与HLA-DR+呈正相关(r=0.65,P＜0.01),与APACHE Ⅱ评分无相关(r=-0.38,P＞0.05).结论 重症肺炎患者外周血中T细胞协同刺激分子表达异常:CD86+下降,而CD28+、CD152+升高,重症肺炎患者外周血T细胞处于"无能"状态;重症肺炎患者恢复期CD28+、CD86+、CD86+、HLA-DR+升高,提示适度的特异性免疫有利于重症肺炎患者康复.CD86+、CTLA4与HLA-DR+相关,进一步说明CD28+/CD152+:B7协同刺激分子可能与重症肺炎的发生、发展有关.

Role of CD28+/CTLA-4:B7costimulators in immune pathophysiology of severe pneumonia

Objective To explore the possible role of CD28 +/CD152 +:B7 eostimulators in immune pathophysiology of severe pneumonia.Methods 22 severe pneumonia peripheral blood sample were used to analyze the expression of CD3+ T cell CD28+,CD152+,CD14++ on mononuelear cell CD86+,and HLA - DR + by FACS expression.The relationship between CD28+,CTLA4,CD86+ and the HLA-DR +,and the relationship between APACHE Ⅱ Grading,CD28+,CD152+,CD86+ and HLA-DR + were analyzed.Results Compared with the control group,the expression of CD3 + T cell,CD86+ and HLA - DR + were remarkably reduced while the expression of CD28+ and CD152+ were markedly increased in patients with severe pneumonia who were hospitalized in 24 h(P＜0.05).However,T cells with positive CD8+ CD3+ and CD4+ CD3+ had no significant change between two groups(P＞0.05).For patients with severe pneumonia who survived,the APACHE Ⅱ scores were significantly reduced while the expression of CD28+,CD152+,CD86+,HLA-DR + and CD3+ + cells were significantly increased after 10 days from admission(P＜0.05).By contrast,T cells with positive CD8+ CD3+ and CD4+CD3+ had no significant change between two groups(P＞0.05).There were no relation between costimulators CD28+ and HLA - DR + (r=-0.12,P=0.54)and APACHE Ⅱ scores(r=-0.30,P=0.19) in control group.CD86+ and HLA - DR + showed positive correlation(r=0.65,P=0.00).CD86+ and APACHE Ⅱ scores had no correlation(r=-0.38,P=0.09).Conclusion The costimulators expressed abnormally in circumference blood of patients with severe pneumonia,CD86+ decreased,but CD28+,CD152+ increased.T cell of circumference blood was at the condition of "anergy".The increase of CD28+,CD86+,CD86+ and HLA - DR + during convalescence stages in patient with severe pneumonia showed that spocific immunity was advantageous for restoration in these patients.The relationship among CD86+,CTLA4 and HLA - DR + indicated that CD28+/CD152+:B7 play an role in the occurrence and development of severe pneumonia.