隐孢子虫感染动物模型的建立及其免疫机制研究

发布时间：2018-04-11 10:19

本文选题：隐孢子虫感染 + CD4~+/CD8~+值　；参考：《新疆医科大学》2010年硕士论文

【摘要】：目的:建立大鼠感染水源性隐孢子虫的动物模型,进行辅助性T淋巴细胞检测,观察感染隐孢子虫后,大鼠脾脏细胞、小肠细胞、小肠粘膜下集合淋巴结细胞CD4~+、CD8~+、CD4~+/CD8~+的变化情况;测定乳鼠感染隐孢子虫后细胞因子IL-2浓度的变化情况。方法:将30只SD大鼠随机分为营养不良组、免疫抑制组和空白对照组。营养不良组采用8%低蛋白饲料喂养,免疫抑制组每天腹腔注射地塞米松,分别处理11 d。从湖水中过滤得隐孢子虫卵囊,分2次灌胃三组大鼠,每次灌胃量为3×10~3个/只,大鼠第2次感染隐孢子虫后1周处死。取小肠组织,做病理切片,观察隐孢子虫感染情况;取脾脏、小肠粘膜集合淋巴结及小肠组织分别做成细胞悬液,用流式细胞检测仪检测T淋巴细胞,计算CD4~+、CD8~+、CD4~+/CD8~+值;对4日龄昆明种乳鼠灌胃隐孢子虫卵囊3×10~3个/只。一周后,计数乳鼠腹腔巨噬细胞吞噬鸡红细胞吞噬百分率及吞噬指数,观察感染隐孢子虫卵囊小鼠脾脏细胞因子IL-2浓度变化。结果:空白对照组大鼠体重增长明显,脾脏发育良好,小肠粘膜下集合淋巴结清晰可见,小肠内无隐孢子虫卵囊定植;营养不良组大鼠体重增长缓慢,小肠粘膜下集合淋巴结可见,小肠内有隐孢子虫卵囊定植;免疫抑制组大鼠体重有所下降,脾脏严重发育不全,小肠粘膜下集合淋巴结不可见,小肠内有隐孢子虫卵囊定植;免疫抑制组大鼠脾脏、小肠及粘膜T淋巴组织中的CD4~+值、CD8~+值、CD4~+/CD8~+比值与营养不良组和空白对照组大鼠比较差异均有统计学意义(p0.05);感染隐孢子虫卵囊的乳鼠其鸡红细胞吞噬指数和吞噬百分率降低,细胞因子IL-2浓度降低,与对照组相比差异有统计学意义(p0.05)。结论:免疫抑制和营养不良大鼠较空白对照组大鼠易感染隐孢子虫卵囊,CD4~+、CD4~+/CD8~+值降低显著;乳鼠感染隐孢子虫卵囊后细胞因子IL-2浓度降低。
[Abstract]:Objective: to establish an animal model of rat infected with water source Cryptosporidium and to detect the helper T lymphocytes and observe the spleen cells and small intestinal cells of the rats infected with Cryptosporidium.The changes of CD4 ~ + CD8 ~ + CD4 ~ / CD8- / CD8 ~ and the change of cytokine IL-2 concentration after infection with Cryptosporidium were measured.Methods: thirty SD rats were randomly divided into malnutrition group, immunosuppressive group and blank control group.The malnutrition group was fed with 8% low protein diet, and the immunosuppressive group was treated with dexamethasone daily for 11 days.Cryptosporidium oocysts were filtrated from lake water. The rats were divided into three groups. The rats were given 3 脳 10 ~ 3 rats each time. The rats were killed 1 week after infection with Cryptosporidium.The intestinal tissues were taken as pathological sections to observe the infection of Cryptosporidium, the spleen, small intestinal mucosal lymph nodes and small intestinal tissues were made into cell suspensions, T lymphocytes were detected by flow cytometry, and the value of CD4 ~ + CD8 ~ + CD4 ~ / CD8 ~ ~ was calculated.3 脳 10 ~ 3 oocysts of Cryptosporidium spp.After one week, the phagocytic percentage and phagocytic index of chicken erythrocytes were counted and the changes of IL-2 concentration of spleen cytokines in mice infected with Cryptosporidium oocysts were observed.Results: in the blank control group, the weight increased significantly, the spleen developed well, the submucosal lymph nodes of the small intestine were clearly visible, and there was no cryptosporidium oocyst colonization in the small intestine.Cryptosporidium oocyst colonization was found in the submucous lymph nodes of the small intestine, the weight of the immunosuppressive group was decreased, the spleen was not fully developed, the submucosal lymph nodes were not visible, and the cryptosporidium oocysts were colonized in the small intestine.Spleen of immunosuppressive group,The ratio of CD4 ~ / / CD8 ~ ~ in small intestine and mucosal T-lymphoid tissue was significantly higher than that in malnutrition group and blank control group (P < 0.05), but the phagocytosis index and percentage of chicken erythrocyte were decreased in chicks infected with Cryptosporidium oocysts.The concentration of cytokine IL-2 was significantly lower than that of control group (P 0.05).Conclusion: immunosuppressive and dystrophy rats are more susceptible to infection of Cryptosporidium oocysts than those of the control group, and the concentration of cytokine IL-2 after infection with Cryptosporidium oocysts in neonatal rats is significantly lower than that in the control group.
【学位授予单位】：新疆医科大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：R-332

【参考文献】