东方田鼠免疫抑制模型对日本血吸虫感染性的研究

Application of An Immunosuppressed Microtus fortis Animal Model to Study the Infection of Schistosoma japonicum

目的建立东方田鼠免疫抑制模型,初步探讨淋巴细胞在东方田鼠抗血吸虫病机制中的作用。方法成年健康的东方田鼠40只,分成4组(每组10只):免疫抑制+血吸虫感染组、免疫抑制组、血吸虫感染组和空白对照组。免疫抑制剂每周注射3次,连续使用6周,建立东方田鼠免疫抑制的动物模型,用脾淋巴细胞转化试验和ELISA抗体检测进行免疫抑制模型的初步鉴定。在尾蚴攻击感染各组动物后42d,麻醉处死各组动物后进行解剖,灌注冲虫,收集虫体和肝脏虫卵镜检。结果免疫抑制模型淋巴细胞增殖受到显著抑制;免疫抑制组血吸虫抗体水平显著低于未抑制组和空白对照组;免疫抑制和未抑制的东方田鼠均未检出成虫和虫卵。结论成功建立东方田鼠免疫抑制模型,淋巴细胞在东方田鼠抗血吸虫病机制中可能不发挥直接作用。

Objective To establish an immunosuppressed Microtus fortis（Mf） animal model,and to evaluate the role of T and B lymphocytes in the natural resistance against Schistosoma japonicum using this model.Methods 40 adult healthy Mf were divided into four groups：treatment with immunosuppressive drugs and S.japonicum infection（group A）,immunosuppressive drugs only（group B）,S.japonicum infection only（group C） and the control animals（group D）.To establish the immunosuppression model,the animals were then injected with inmunosuppresive drugs three times per week for 6 weeks.The state of immunosuppression was confirmed with the lymphocyte proliferation and ELISA assays.Animals were anaethesized and executed on day-42 post-infection.Perfusion method was used to collect adult worms from the mesenteric veins.Eggs in the liver were observed under microscope.Results In the immunosuppressed animals,lymphocytes proliferation was significantly suppressed and the level of IgG antibody against schistosoma was lower than the other groups.Adult worms and eggs were not found in both of immunosuppressed and non-suppressed animals.Conclusion T and B-cell do play a direct role in the resistance of S.japonicum infection in M.fortis.