共刺激分子B7及其受体CD28、OX40和CD11a在大鼠心脏移植排斥反应中的变化

The changes of costimulatory molecule B7 and its receptor CD28,OX40 and CD11a in rat cardiac allograft rejection

目的探讨共刺激分子B7-1、B7-2分子及其受体CD28和OX40、CD11a在大鼠心脏移植排斥中的作用及意义。方法用流式细胞术检测大鼠异位心脏移植术前和术后不同时间外周血白细胞B7分子、OX40、CD11a及淋巴细胞CD28的表达变化。结果术后淋巴细胞、单核细胞B7-1、B7-2、OX40、CD11a的表达变化与排斥反应的进程有关,高峰值均出现在术后第7d 或维持高峰平台至术后第7d,此时移植物排斥反应多表现为2～3级,淋巴细胞CD28的表达在移植前后和排斥反应程度之间无显著性变化。结论共刺激分子B7-1、B7-2分子、OX40、CD11a在移植排斥反应的较早阶段可能发挥重要的作用,动态监测外周血淋巴细胞、单核细胞B7-1、B7-2、OX40、CD11a的表达有助于临床移植排斥反应的评价。

Objective To explore the significance of B7 molecule and its receptor CD28, OX40 and CD11a in rat cardiac allograft rejection. Methods The changes of B7 molecule, OX40 and CD11a in peripheral blood white cells and CD28 in lymphocytes were detected by flow cytometry preoperatively and 3,5,7,14 days postoperatively in rat cardiac allograft recipients. Results The changes of B7-1 and B7-2 and OX40 and CD11a in peripheral blood lymphocytes and mononuclear are associated with the course of rejection. The peak values of B7-1 ,B7-2 ,OX40 and CD11a in peripheral blood lymphocytes and mononuclear were observed at the seventh postoperative day, meanwhile the degree of graft rejection was moderate (grade 2 to grade 3) . The level of CD28 expression on lymphocytes had no difference significantly between preoperation and postoperation. Conclusion The results suggests that costimulatory molecule B7,OX40 and CD11a may play important roles in the course of rejection prior to significant graft destruction and it might be a useful indicator for diagnosis of acute cardiac allograft rejection.