大鼠脑组织损伤后局部及血液中细胞免疫状况的改变

Change of cell immune state in local brain tissue and peripheral blood after brain trauma in rats

目的研究大鼠脑组织损伤后局部及外周血中细胞免疫状况的改变,探讨脑组织的保护及全身性感染的防治。方法制作大鼠自由落体脑损伤模型,应用免疫组化及ELISA方法,在不同的时程检测脑组织局部淋巴细胞浸润、外周血淋巴细胞的增殖活性、IFNγ及IL-10的含量。结果伤后10d,损伤灶周边脑组织内T淋巴细胞浸润明显增加,CD8^+/CD4^+T淋巴细胞增多更显著,每高倍视野下两者比值约为300∶270；而外周血中T淋巴细胞增殖活性减弱,IFNγ活性下降、IL-10活性增高。结论颅脑损伤后,损伤灶局部细胞免疫明显增强,外周血中细胞免疫减弱,且发生功能转化,导致Ⅳ型超敏反应显著减弱。

Objective To research the change of immune state in local brain tissue and peripheral blood after brain trauma, to discuss how to protect brain and to prevent and treat systemic infection. Methods After execution of brain trauma model in rats by freedrop object, at different periods, we observed the soakage of lymphocytes in the traumatic area, measure the proliferation activity of lymphocytes and the content of IFNγ and IL- 10 in peripheral blood with immunohistochemistry and ELISA. Results 10 d after trauma, there were a significant increased soakage of T-lymphocytes in brain tissue around traumatic area, especially for CD8^＋T-lymphocytes. The rate of CD4^＋/CD8^＋ was about 300：270 in every high power field. However, in peripheral blood, the proliferation activity of T-lymphocytes and the content of IFNγ decreased, IL-10 increased. Conclusion After brain trauma, the cell immunocompetence were obviously enhanced in the local trauma area, hut they were decreased in peripheral blood. Furthermore, their function transformed so that Ⅳ-supersensitive responding decreased remarkably.