Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi, Thailand.
Immunol Invest. 2009;38(8):762-79. doi: 10.3109/08820130903070544.
The HIV-1 CRF01_AE gag gene was modified by codon restriction for Mycobacterium spp. and transformed into BCG; and it was designated as rBCG/codon optimized gagE. This produced 11 fold higher HIV-1 gag protein expression than the recombinant native gene rBCG/HIV-1gagE. In mice, CTL activity could be induced either by a single immunization of the codon optimized construct or by using it as a priming antigen in the prime-boost modality with recombinant Vaccinia virus expressing native HIV-1 gag. Specific secreted cytokine responses were also investigated. Only when rBCG gag was codon optimized did the prime-boost immunization produce significantly enhanced IFN-gamma and IL-2 secretion indicating recognition via CD4+ and CD8+ T cells, and these responses seemed to be codon optimized immunogen dose-responsive. On contrary, the prime-boost vaccination using an equal amount of native rBCG/HIV-1gagE instead, or a single rBCG/codon optimized gagE immunization, had no similar effect on the cytokine secretion. These findings suggest that the use of recombinant codon BCG construct with recombinant Vaccinia virus encoding CRF01_AE gag as the prime-boost HIV vaccine candidate, will induce CD4+ Th1 and CD8+ T cell cytokine secretions in addition to enhancing CD8+ CTL response.
HIV-1 CRF01_AE 的 gag 基因经过密码子限制修饰后转入 BCG，命名为 rBCG/codon 优化 gagE。与重组天然基因 rBCG/HIV-1gagE 相比，该基因表达 HIV-1 gag 蛋白的能力提高了 11 倍。在小鼠中，单次免疫编码优化构建体或使用其作为重组痘苗病毒表达天然 HIV-1 gag 的初免-加强免疫模式的启动抗原，均可诱导 CTL 活性。还研究了特异性分泌细胞因子的反应。只有当 rBCG gag 进行密码子优化时，初免-加强免疫才会显著增强 IFN-γ和 IL-2 的分泌，表明通过 CD4+和 CD8+T 细胞识别，并且这些反应似乎与密码子优化免疫原的剂量呈正相关。相反，使用等量的天然 rBCG/HIV-1gagE 替代初免-加强免疫，或单独使用 rBCG/codon 优化 gagE 免疫，对细胞因子分泌没有类似的影响。这些发现表明，使用重组密码子 BCG 构建体和编码 CRF01_AE gag 的重组痘苗病毒作为初免-加强 HIV 疫苗候选物，除了增强 CD8+CTL 反应外，还会诱导 CD4+Th1 和 CD8+T 细胞细胞因子的分泌。
