CTL Effectors in Bovine Congenital Neosporosis

描述（由申请人提供）：申请人拟研究的角色 CTL在控制经胎盘的犬新孢子虫传播中的作用 远系繁殖的牛宿主哺乳动物宿主感染N.犬经验 免疫期间感染复发和速殖子寄生虫血症 抑制或怀孕导致胎儿感染，寄生虫性脑炎， 在某些宿主种群内，通过垂直传播， 传输细胞毒性T淋巴细胞（CTL）在免疫调节中起重要作用 小鼠感染T.弓形虫，通过过继转移证明， 消耗研究。CD8+细胞毒性效应子和显性1型免疫 应答与细胞内顶复菌感染消退相关。 SAG 1是T.弓形虫 产生保护性免疫，可以通过SAG 1进行过继转移 特异性CTL。感染N.犬抗原 保护免受T.提示保护性CTL可能 由同源抗原诱导。在新孢子虫病的小鼠妊娠模型中， 中和2型反应与N.犬抗原引发 减少经胎盘传播。拟议研究 将检验用N.犬抗原识别 细胞毒性淋巴细胞将限制先天性N。犬传染病 牛该项目的重点是NcSAG1，主要的表面抗原。

DESCRIPTION (provided by applicant): The applicant proposes to study the role of CTL's in the control of transplacental Neospora caninum transmission in an outbred bovine host. Mammalian hosts infected with N. caninum experience recrudescence of infection and tachyzoite parasitemia during immune suppression or pregnancy leading to fetal infection, parasitic encephalitis, and persistence of infection within some host populations via vertical transmission. Cytotoxic T lymphocytes (CTL s) are important in immune control of murine infections with T. gondii, demonstrated by adoptive transfer and depletion studies. CD8+ cytotoxic effectors and a dominant type 1 immune response correlate with resolution of intracellular apicomplexan infections. Mice immunized with SAG1, an immunodominant surface protein of T. gondii develop protective immunity that can be adoptively transferred with SAG1 specific CTL's. CD8+ T lymphocytes from mice infected with N. caninum antigen protect against challenge with T. gondii, suggesting that protective CTLs may be induced by homologous antigens. In murine pregnancy models of neosporosis, neutralization of a type 2 response together with N. caninum antigen priming prior to gestation decrease transplacental transmission. The proposed research will test the hypothesis that immunization with N. caninum antigens recognized by cytotoxic lymphocytes will limit congential N. caninum transmission in cattle. The project focuses upon NcSAG1, the major surface antigen.