Rosas Cristina T, Paessler Slobodan, Ni Haolin, Osterrieder Nikolaus
Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA.
Am J Trop Med Hyg. 2008 Jan;78(1):83-92.
A vectored vaccine based on equine herpesvirus type 1 (EHV-1) was generated as an alternative for safe and efficient prophylaxis against Venezuelan equine encephalitis virus (VEEV) infection. Two-step (en passant) Red mutagenesis was used to insert VEEV structural genes into an infectious clone of EHV-1 vaccine strain RacH. The recombinant virus, rH_VEEV, efficiently and stably expressed VEEV structural proteins as detected by various antibodies, including a conformation-dependent monoclonal antibody to envelope glycoprotein E2. In addition, rH_VEEV was indistinguishable from parental bacterial artificial chromosome-derived virus with respect to growth properties in cultured cells. Immunization of mice with the vectored vaccine conferred full protection against lethal challenge infection using VEEV strain ZPC738 in the absence of neutralizing antibodies and in a dose-dependent manner. Analyses of IgG responses demonstrated production of VEEV-specific IgG1 and total IgG antibodies after vaccination, indicating that protection was dependent on either cytotoxic T cell responses or antibody-mediated protection unrelated to neutralizing activity.
一种基于1型马疱疹病毒（EHV-1）的载体疫苗被开发出来，作为安全有效地预防委内瑞拉马脑炎病毒（VEEV）感染的替代方法。采用两步（顺向）Red诱变将VEEV结构基因插入EHV-1疫苗株RacH的感染性克隆中。重组病毒rH_VEEV能高效稳定地表达VEEV结构蛋白，各种抗体检测均能证实，包括针对包膜糖蛋白E2的构象依赖性单克隆抗体。此外，在培养细胞中的生长特性方面，rH_VEEV与亲本细菌人工染色体衍生病毒没有差异。用该载体疫苗免疫小鼠，在没有中和抗体的情况下，能以剂量依赖的方式对VEEV毒株ZPC738的致死性攻击感染提供完全保护。IgG反应分析表明，接种疫苗后产生了VEEV特异性IgG1和总IgG抗体，这表明保护作用依赖于细胞毒性T细胞反应或与中和活性无关的抗体介导的保护作用。
