伊氏锥虫在小鼠体内抗原变异规律及免疫保护试验  

Regularity of Antigenic Variation in T.evansi in Mice and Experiments on Immune Protection According to Regularity of Antigenic Variation

作　　者：王权[1] 沈杰[1] 周勇志[1] 周金林[1] 

机构地区：[1]中国农业科学院上海家畜寄生虫病研究所,上海200232

出　　处：《中国兽医学报》2003年第2期160-163,共4页Chinese Journal of Veterinary Science

基　　金：国家自然科学基金资助项目 (3 9670 5 60 )

摘　　要：为了探索伊氏锥虫抗原的变异规律及其用于免疫预防的可能性 ,首先对伊氏锥虫安徽株单虫克隆 2个早期变异体 Sh Tat1.1、Sh Tat1.2采用蛋白酶抑制剂 TL CK处理 ,分离纯化这 2种变异体的 VSG,用 Sh Tat1.1VSG免疫 KM小鼠 ,Sh Tat1.1锥虫攻击免疫鼠后 6 d分离锥虫 ,经间接免疫荧光试验 (IFT)和班点酶标记试验 (Dot- EIA)鉴定为Sh Tat1.2 ,说明同一克隆锥虫感染兔、小鼠第 1次发生抗原变异后产生的变异体相同。依据这一规律 ,设计了免疫预防保护试验 ,试验小鼠分 3组 :一组为未免疫对照组 ,一组为 Sh Tat1.1VSG单一抗原免疫组 ,另一组为 Sh Tat1.1VSG、Sh Tat1.2 VSG混合免疫抗原免疫组 ,各组均以 Sh Tat1.1锥虫攻击 ,结果 Sh Tat1.1VSG+Sh Tat1.2 VSG免疫组小鼠全部获得保护 ,单用 Sh Tat1.1VSG免疫组小鼠和未免疫小鼠血中全部出虫、死亡 ,前者比后者出虫时间、存活时间延长。提示运用伊氏锥虫抗原变异这一规律设计的这种复合抗原 ,能激发宿主克服虫体抗原变异对免疫保护的干扰。In order to find out regularity of antigenic variation in T.evansi and probe a new measure to improve the protective immunity against T.evansi according to it.At first two kinds of VSGs(from ShTat1.1 and ShTat1.2) were isolated and purified by applying proteolytic enzyme inhibiter TLCK.KM mice immunized with ShTat1.1 VSG was challenged with ShTat1.1 Trypanosomas.Trypanosomas in blood of the mice were isolated and determined to be ShTat1.2 by IFT and Dot-EIA.It is showed that T.evansi deriving from a cloned stoke changed their antigen into a new type of T.evansi at first time which is same between in the immunized mice and in rabbits.The compound immunoprophylaxis test was carried out according to regularity of antigenic variation in Trypanosomas.Mice were divided into three groups.One received antigen free,another received ShTat1.1 VSG alone,the third received both ShTat1.1 VSG and ShTat1.2 VSG.All mice were challenged with 100 ShTat1.1 Trypanosomas,the mice non-vaccinated or vaccinated with ShTat1.1 VSG were all died on 8th day and 10th day respectively,the Trypanosomas were discovered in tail blood of mice on 5th day and 7th day respectively,but all mice immunized with two VSGs were survived.It is suggested that immunoprophylaxis test designed according to some regularity of antigenic variation in T.evansi may give stronger protective effect.

关 键 词：免疫保护试验 伊氏锥虫 抗原变异规律 家畜 

分 类 号：S852.729[农业科学—基础兽医学]