日本血吸虫虫卵在诱导型一氧化氮合酶敲除大鼠中的分布  

Distribution of Schistosoma japonicum eggs in inducible nitric oxide synthase knockout rats

作　　者：彭美 伦照荣[3] 吴忠道 沈佳[1,2] PENG Mei;LUN Zhao-rong;WU Zhong-dao;SHEN Jia(Department of Parasitology,Zhongshan Medical College,Sun Yat-sen University,Guangzhou,Guangdong 510080;Key Laboratory of Tropical Disease Prevention and Control,Ministry of Education,Guangzhou,Guangdong 510080;School of Life Sciences,Sun Yat-sen University,Guangzhou,Guangdong 510275,China)

机构地区：[1]中山大学中山医学院寄生虫学教研室,广东广州510080 [2]中山大学热带病防治研究教育部重点实验室,广东广州510080 [3]中山大学生命科学院,广东广州510275

出　　处：《热带医学杂志》2021年第4期398-401,412,I0001,共6页Journal of Tropical Medicine

基　　金：国家自然科学基金(81802036);中国博士后科学基金(2018M631027,2019T120770);广东省自然科学基金(2020A1515010896);中央高校基本科研业务费专项资金(19ykpy165)。

摘　　要：目的观察血吸虫虫卵在野生型(WT)大鼠和诱导型一氧化氮合酶敲除(iNOS^(-/-))大鼠肝肠组织及粪便中的分布情况,分析iNOS在感染大鼠中对日本血吸虫感染及虫卵产生的影响。方法采用WT大鼠和iNOS^(-/-)大鼠构建日本血吸虫感染实验动物模型。采用碱消化组织虫卵计数法及改良加藤厚涂片法检测日本血吸虫虫卵在大鼠肠组织和粪便中的分布,并用透射电镜观察虫卵内部结构,随后采用HE染色和环卵沉淀实验检测日本血吸虫感染7周后大鼠体内虫卵的活性。结果日本血吸虫感染7周后,WT大鼠虫卵仅少量分布于肝组织中,而在肠组织和粪便中均未发现虫卵。iNOS^(-/-)大鼠虫卵大量沉积于肝组织中,且在肠组织和粪便中均发现有虫卵。透射电镜结果显示,与WT大鼠中的虫卵比较,iNOS^(-/-)大鼠体内的虫卵结构更为完整,并可见到毛蚴。另外,iNOS^(-/-)大鼠的肠组织中形成了虫卵肉芽肿,而WT大鼠的肠组织中并未发现有虫卵肉芽肿。通过环卵沉淀实验进一步发现,与WT大鼠比较,iNOS^(-/-)大鼠中收集的虫卵周围出现了大量的阳性反应,且虫卵周围可见大量沉淀反应。结论日本血吸虫感染i NOS-/-大鼠后可产生具有较强抗原分泌能力的成熟虫卵,进而改变日本血吸虫虫卵在大鼠体内的分布,即虫卵可到达大鼠的肠组织及粪便,且可排出到体外。Objective To compare the distribution of eggs in liver and intestine tissues and feces of the two kinds of rats,and investigate the effect of inductive nitric oxide synthase knockout(iNOS^(-/-))on the infection of Schistosoma japonicum and the production of eggs in infected rats.Methods To establish an experimental animal model of S.japonicum infection by wild type(WT)rats and iNOS rats.The distribution of S.japonicum eggs in the intestinal tissues and feces of rats was detected by egg counting after tissue digestion and Kato-Katz method.The internal structure of S.japonicum eggs was observed by transmission electron microscopy.The egg activity in the rats was detected by HE staining and circumoval precipitation test after 7 weeks of S.japonicum infection.Results Seven weeks after S.japonicum infection,only a small number of eggs were found in liver tissue of WT rats,but no eggs were found in intestinal tissue or feces.However,in iNOS^(-/-)rats,a large number of eggs were deposited in liver tissue,and they were found in intestinal tissue and feces.The results of transmission electron microscopy showed that compared with the eggs in WT rats,the structure of the eggs in iNOS^(-/-)rats was more complete,and the miracidia were visible.In addition,there were egg granulomae in intestinal tissues of iNOS^(-/-)rats,while WT rats had no egg granuloma.It was further found that eggs isolated from liver of iNOS^(-/-)rats had stronger antigen secretion ability compared with WT rats by circumoval precipitation test.Conclusions iNOS^(-/-)rats infected by S.japonicum could produce mature eggs with strong antigen-secreting ability,and then change the distribution of S.japonicum eggs in rats.The eggs could reach the intestinal tissue and feces of rats,and could be excreted outside of the body.

关 键 词：日本血吸虫 虫卵 大鼠 INOS 

分 类 号：R383.24[医药卫生—医学寄生虫学]