日本血吸虫感染BALB／c小鼠脾脏细胞学的变化

目的观察BALB／c小鼠感染日本血吸虫（Schistosoma japonicum，$）6．8周后脾脏细胞学的改变情况。方法用日本血吸虫尾蚴腹贴法建立日本血吸虫感染的小鼠模型。6～8周后观察肝脏、脾脏大小．称重：做脾脏淋巴细胞计数；用流式细胞仪检测脾脏淋巴细胞的大小、密度和T、B细胞分类以及Th细胞亚群睛况：用酶联免疫吸附实验（enzyme linked immunosorbent assay，ELISA）检测血清中可溶性虫卵抗原（soluble egg antigen，SEA）所诱导的特异性抗体IgG的产生情况。结果日本血吸虫感染BALB／c小鼠6～8周后，脾脏体积明显增大，重量增加，细胞数量明显增多。流式细胞仪检测发现脾脏中出现一群体积明显增大的细胞群，该群细胞表达少量的CD4、CD8、CD19和DX－5分子；Th1／Th2轴发生偏移，Th17细胞数量增多；ELISA结果表明血清中SEA特异性抗体IgG水平明显升高。结论日本血吸虫感染的BALB／c小鼠脾脏出现明显的细胞学改变，尤其是Th1细胞数目下降，浆细胞、Th2细胞及Th17细胞数目增多，为研究日本血吸虫感染后期虫卵肉芽肿形成的免疫病理机制奠定了基础。

Changes of Cytology of Spleen in BALB/c Infected with Schistosoma japonicum

Objective To investigate the change of cytology of spleen in BALB/c mice infected by S.japonicum for 6-8 weeks. Method After mice were infected with S.japonicum cercariea by applying to abdomen walls for 6-8 weeks. The size and weight of liver and spleen were observed. The numbers of spleen lymphocytes were counted. The size and density of spleen lymphocytes and the sorts of T, B cells and subset of T help cells were detected by flow cytometry. The serum specific IgG level induced by soluble egg antigen （SEA） was detected by ELISA. Result The size and weight of spleen and the number of spleen lymphocytes in infected mice increased obviously. There was a big cell population in spleen that expressed low lever CD4, CD8, CD19 and DX-5. The axis of Th1/Th2 shifted and the numbers of Th17 cells increased. The level of serum specific anti-SEA IgG increased obviously. Conclusion The spleen of BALB/c mice infected with S.japonicum has significant changes in cytology, especially decrease in Thl cells and plasma cells, and increase in Th2 cells and Th17 cells. This provides a foundation for studying the mechanism of egg granuloma in the later phase of infection.