Purdy M A, McCaustland K A, Krawczynski K, Spelbring J, Reyes G R, Bradley D W
Hepatitis Branch, Centers for Disease Control, Atlanta, Georgia 30333.
J Med Virol. 1993 Sep;41(1):90-4. doi: 10.1002/jmv.1890410118.
Immunization of two cynomolgus macaques (cynos) with trpE-C2 protein, a trpE-HEV fusion protein that represents the carboxyl two thirds of the putative capsid protein, prevented development of biochemical evidence of viral hepatitis in these primates after challenge by wild-type HEV from either a Burmese or Mexican stool isolate. Neither of the immunized animals showed any elevation of alanine aminotransferase activity after challenge with wild-type HEV in marked contrast with the unimmunized (control) cynos. In the case of the Burmese HEV challenged cyno, the protective effect was complete with the animal failing to demonstrate any evidence of HEV infection. The immunized cyno challenged with Burmese HEV did not exhibit any HEV RNA in its stools or HEV antigen in its liver. The immunized cyno (#8902) challenged with Mexican virus exhibited HEV RNA in its stools and HEV antigen in its liver; however, microscopic examination of liver biopsy specimens from this cyno failed to detect histopathologic evidence of viral hepatitis. All of the animals (naive and immunized) developed anti-HEV IgM and IgG responses after HEV challenge. Our preliminary studies indicate that the trpE-C2 protein is a promising candidate HEV vaccine.
用trpE-C2蛋白（一种代表假定衣壳蛋白羧基三分之二的trpE-戊型肝炎病毒融合蛋白）对两只食蟹猴进行免疫，可防止这些灵长类动物在受到来自缅甸或墨西哥粪便分离株的野生型戊型肝炎病毒攻击后出现病毒性肝炎的生化证据。与未免疫（对照）的食蟹猴形成鲜明对比的是，在用野生型戊型肝炎病毒攻击后，两只免疫动物的丙氨酸转氨酶活性均未升高。在用缅甸戊型肝炎病毒攻击的食蟹猴中，保护作用是完全的，该动物未表现出任何戊型肝炎病毒感染的证据。用缅甸戊型肝炎病毒攻击的免疫食蟹猴粪便中未检测到任何戊型肝炎病毒RNA，肝脏中也未检测到戊型肝炎病毒抗原。用墨西哥病毒攻击的免疫食蟹猴（#8902）粪便中出现了戊型肝炎病毒RNA，肝脏中出现了戊型肝炎病毒抗原；然而，对该食蟹猴肝脏活检标本的显微镜检查未发现病毒性肝炎的组织病理学证据。所有动物（未免疫和免疫的）在受到戊型肝炎病毒攻击后均产生了抗戊型肝炎病毒IgM和IgG反应。我们的初步研究表明，trpE-C2蛋白是一种有前景的戊型肝炎病毒候选疫苗。
