Chunling Ma, Kun Yao, Jian Xu, Jian Qin, Hua Sun, Minsheng Zhu
Department of Microbiology and Immunology, Nanjing Medical University, Nanjing, PR China.
Intervirology. 2006;49(5):307-18. doi: 10.1159/000094247. Epub 2006 Jun 29.
To investigate immunogenicity in the induction of humoral and cellular immune responses to genetic vaccines of the recombinant severe acute respiratory syndrome-associated coronavirus (SARS-CoV)-N gene expressing the same protein plasmid, pcDNA3.1-N, and replication-defective adenoviral vector, rAd-N, in a pcDNA3.1-N prime-rAd-N boost regimen and the reverse sequence in a rAd-N prime-pcDNA3.1-N boost regimen.
After the mice had been immunized intramuscularly and/or intraperitoneally with pcDNA3.1-N and rAd-N in prime-triple boost immunization, humoral and cellular immune responses were detected.
After detection, different levels of anti-N humoral and cellular responses are shown compared to controls. The humoral immune response was induced more effectively by the DNA priming and recombinant adenovirus boosting regimen and the reverse sequence of heterogeneous combinations. There is a significant difference between heterogeneous and homologous vaccinations. However, the cytotoxic T lymphocyte (CTL) response was not significantly altered by the different prime-boost immunizations or the recombinant adenovirus of pcDNA3.1-N prime-rAd-N boost regimen alone, but lymphoproliferation and interferon-gamma (IFN-gamma) secretion were all enhanced by heterologous combination immunizations compared to homologous combinations. For the reverse sequence immunization regimen, lymphoproliferation, IFN-gamma and CTL responses were all significantly weaker compared with pcDNA3.1-N prime-rAd-N boost regimen.
Taken together, of all the combinations, the prime-triple boost immunization of pcDNA3.1-N/pcDNA3.1-N/pcDNA3.1-N/rAd-N can effectively induce SARS-CoV-N-specific and strong humoral and cellular immune responses in mice. The present results suggest that DNA immunization followed by recombinant adenovirus boosting could be used as a potential SARS-CoV vaccine in the induction of an enhanced humoral and cellular immune response.
研究在pcDNA3.1-N初免-rAd-N加强免疫方案以及rAd-N初免-pcDNA3.1-N加强免疫方案的反向序列中，表达相同蛋白质质粒pcDNA3.1-N的重组严重急性呼吸综合征相关冠状病毒（SARS-CoV）-N基因的基因疫苗诱导体液免疫和细胞免疫反应的免疫原性。
小鼠经肌肉注射和/或腹腔注射pcDNA3.1-N和rAd-N进行初免-三次加强免疫后，检测体液免疫和细胞免疫反应。
检测后发现，与对照组相比，显示出不同水平的抗N体液免疫和细胞免疫反应。DNA初免和重组腺病毒加强免疫方案以及异源组合的反向序列能更有效地诱导体液免疫反应。异源和同源疫苗接种之间存在显著差异。然而，不同的初免-加强免疫或单独的pcDNA3.1-N初免-rAd-N加强免疫方案的重组腺病毒并未显著改变细胞毒性T淋巴细胞（CTL）反应，但与同源组合相比，异源组合免疫增强了淋巴细胞增殖和干扰素-γ（IFN-γ）分泌。对于反向序列免疫方案，与pcDNA3.1-N初免-rAd-N加强免疫方案相比，淋巴细胞增殖、IFN-γ和CTL反应均显著较弱。
综上所述，在所有组合中，pcDNA3.1-N/pcDNA3.1-N/pcDNA3.
