X射线全身照射对小鼠免疫功能的影响

目的:通过X-射线体外全身照射BALB/c小鼠建立小鼠辐射损伤模型,检测放射线对小鼠脾组织、单核巨噬细胞及T、B淋巴细胞损伤的剂量范围,探索放射线剂量与组织损伤程度之间的量效关系。方法:采用9种不同剂量的X-射线体外全身照射BALB/c小鼠,于照射后1d、60d、120d取腹腔细胞做大吞噬实验;分离脾细胞,MTT法检测T细胞增殖活性,同时取脾脏组织切片、HE染色,检测组织损伤程度;照射后120d取小鼠脾细胞用流式细胞仪检测T、B细胞数量百分比。结果:不同剂量X-射线照射的小鼠其大吞噬细胞的吞噬指数及T细胞的增殖指数之间均存在差异,且与放射剂量呈负相关性。FCM检测结果显示0.1Gy及以上剂量组与正常对照组相比较,小鼠T、B淋巴细胞数量减少(P<0.05)。0.25Gy和0.5Gy组T、B淋巴细胞数量明显高于除0.05Gy以外的其余各照射组,但是仍低于正常组(P<0.05)。脾组织切片显示,照射后1d 0.1Gy以上照射组脾脏炎性细胞浸润;60d后,4.0Gy和8.0Gy组脾脏明显萎缩、巨噬细胞增生、瘤样变,其余组损伤不明显;120d后8.0Gy组脾脏萎缩、红白髓分界不清,白髓损伤尤为严重,其余组不明显。结论:0.1Gy以上X-射线体外全身照射可引起小鼠免疫功能及组织损伤,且损伤程度与放射性强度呈剂量依赖性。

The Effect of X-ray on Immune Function in Mice Irradiated Systemly

Objective This study was designated to establish a radiation damage model by whole-body irradiation of different does of X-rays, and to explore dose-effect relationship between radiation and tissue damage. Methods The BALB/c mices＇s was whole-body irradiation. Peritoneal fluid was collected to do the big englobement experiment and the T cells in the spleen was isolated to assess their proliferation by MTT assay. The spleen were observed by HE stain at the 1 day, 60 day and 120 day and the percentage of T and B lymphocyte in spleen cells were deteetde by flow cytometry after 120 days of the ending radiation. Results The phagocytic index of macrophagocyte and the T cells proliferation index in each groups were negative correlation with the radiation dosage. Flow cytometry showed there were no difference between the 0.05Gy X-ray group and the control group, while the dosage was more than 0. 1Gy, the T and B cells was deereased（P 〈0.05）. The amount of T and B cells in dosage group of 0.25Gy and 0.5Gy was lower than control group, but higher than 0. 05Gy group（P 〈0.05）. The histological section showed inflammatory cell infiltrated in 0. 1Gy group after ld. After 60 days, the 4.0Gy and 8.0Gy group showed atrophy and macrophage proliferation, tumor-like change in spleens. After 120 days, the spleen was atrophy, the dividing line between red pulp and white pulp was vague in 8Gy group. Conclution X-rays above 0. 1Gy could lead to immunne function and tissue damage by whole-body irradiation, and the degree of damage was positively correlated with radiation strength.