Bahloul C, Jacob Y, Tordo N, Perrin P
Laboratoire des Lyssavirus, Institut Pasteur, Paris, France.
Vaccine. 1998 Feb;16(4):417-25. doi: 10.1016/s0264-410x(97)00204-1.
DNA-based immunization was used for studying the cross-reactivity of lyssavirus neutralizing antibodies and for exploring the induction of a wider range of protection against lyssaviruses. In order to immunize mice with homogeneous and chimeric genes of glycoproteins (G) from two divergent lyssaviruses, we used for the first time a new plasmid (pCI-neo) known to be a highly efficient vector for in vitro expression. The homogeneous plasmids pGPV and pGMok encoded the Pasteur virus (PV: genotype 1-GT-) and Mokola virus (Mok: GT 3) G, respectively. The chimeric pGMokPV encoded the NH2 part of GMok and the COOH part of GPV. These plasmids elicited full protection against intracerebral challenges with various lyssaviruses and a range of antigen-specific and non-specific immune responses. Virus neutralizing antibody (VNAb) levels were dose dependent and a single intramuscular (i.m.) injection of plasmids was sufficient to induce continuous high levels of VNAb. Production of antigen-specific T helper (Th), cytotoxic T cells (Tc) and non-specific natural killer cells was observed. Cross-reactivity studies showed that VNAb are obtained by immunizing with: (i) pGPV against GT 1 (classical rabies), GT 4 (Duvenhage: Duv), GT 5 (European Bat Lyssavirus: EBL-1) and GT 6 (European Bat Lyssavirus: EBL-2); (ii) pGMok against GT 2 (Lagos Bat: LB) and GT 3 (Mokola: Mok); (iii) pGMokPV against all GTs except GT 4 which is weakly neutralized. Therefore, the DNA-based immunization with the chimeric pGMokPV, could be very interesting to enlarge protection to all the lyssaviruses. According to the cross-reactivity of VNAb induced by the G genes, the lyssavirus GTs could be classified into two groups: the first including GT 1, 4, 5 and 6; the second including GT 2 and 3.
基于DNA的免疫接种被用于研究狂犬病病毒中和抗体的交叉反应性，并探索诱导对狂犬病病毒产生更广泛的保护作用。为了用两种不同狂犬病病毒的糖蛋白（G）的同源基因和嵌合基因免疫小鼠，我们首次使用了一种已知为体外表达高效载体的新质粒（pCI-neo）。同源质粒pGPV和pGMok分别编码巴斯德病毒（PV：基因型1-GT-）和莫科拉病毒（Mok：GT 3）的G。嵌合质粒pGMokPV编码GMok的NH2部分和GPV的COOH部分。这些质粒引发了针对各种狂犬病病毒脑内攻击的完全保护作用以及一系列抗原特异性和非特异性免疫反应。病毒中和抗体（VNAb）水平呈剂量依赖性，单次肌内注射质粒足以诱导持续高水平的VNAb。观察到抗原特异性辅助性T细胞（Th）、细胞毒性T细胞（Tc）和非特异性自然杀伤细胞的产生。交叉反应性研究表明，通过以下方式免疫可获得VNAb：（i）用pGPV针对GT 1（经典狂犬病）、GT 4（杜文海格病毒：Duv）、GT 5（欧洲蝙蝠狂犬病病毒：EBL-1）和GT 6（欧洲蝙蝠狂犬病病毒：EBL-2）；（ii）用pGMok针对GT 2（拉各斯蝙蝠病毒：LB）和GT 3（莫科拉病毒：Mok）；（iii）用pGMokPV针对除GT 4（被弱中和）之外的所有GT。因此，用嵌合质粒pGMokPV进行基于DNA的免疫接种对于扩大对所有狂犬病病毒的保护可能非常有意义。根据G基因诱导的VNAb的交叉反应性，狂犬病病毒GT可分为两组：第一组包括GT 1、4、5和6；第二组包括GT 2和3。
