低剂量辐射对脐血T淋巴细胞膜分子表达的影响

目的 探讨低剂量辐射对人脐血T淋巴细胞膜分子表达的影响。方法 62mGy γ射线照射新鲜分离的脐血淋巴细胞，照前及照后4h、12h、24h采用单克隆抗体直接免疫荧光标记流式细胞术检测TCR、CD3、CD4、CD8分子的表达。结果低剂量辐射后，脐血淋巴细胞CD3、TCR／CD3复合物、CD4、CD8分子表达显上调，且均在4h～24h内随时间推移而逐步增幅；CD3／CD8比值无显性变化。结论 低剂量辐射可促进脐血T淋巴细胞的成熟、活化和信号的转导，从而可能在脐血移植中加速免疫功能重建，增强移植物抗白血病反应(GVL)，降低肿瘤的复发率。

Effect of low dose irradiation on expression of membrane molecules of T lymphocytes from cord blood

Objective To study the expression of membrane molecules of T lymphocytes of cord blood after low dose irradiation(LDI). Methods Freshly isolated lymphocytes from cord blood were irradiated with 62mGy gamma-ray. At different time(4h; 12h;24h) after irradiation, the changes of TCR , CD3 , CD4 , CD8 cells were examined by flow cytometry with direct immunofluorescence, respectively. Results The proportion of CD3 , TCR /CD3 ; CD4 , CD8 cells increased significantly after LDI,the most obvious enhancement was noted in the 24h experimental group were no significant changes in the ratio of CD4 to CD8. Conclusions It is suggested that expedition of the maturation, activation and signal transudation of T lymphocytes from cord blood can be induced by ir- radiation with 62mGy gamma-ray The reconstruction of immune functions after cord blood transplantation may be ac- celerated, enhancing the graft versus leukemia(GVL)effect and preventing the tumor from relapsing.