中文摘要：本研究组已开发出一种H9N2型弱毒活疫苗（LAIVs），该疫苗能够诱导产生抗H9N2病毒的广谱保护作用。本研究分析了这种H9N2弱毒活疫苗对高致病性禽流感病毒H5N2的交叉免疫作用。试验以LAIVs鸡群，以致死剂量的H5N2病毒攻毒鸡群，结果所有鸡只均存活了下来，且病毒增殖和病变得到了有效抑制。采用LAIVs可以显著激活肺部H5N2特异性CD4(+)和CD8(+) T细胞。在H5N2攻毒后，这些LAIV激活的交叉免疫T细胞浓度疯狂增加，这种短暂的增加现象与病毒清除相关。除细胞免疫外，体液免疫同样在交叉免疫过程中发挥了重要作用。被动转移H9N2 LAIV抗血清的鸡群在感染H5N2病毒后能够100%存活。经鉴定发现，这种抗血清包含了抗H5N2病毒的核蛋白（NP）的交叉绑定IgGs，这种IgGs在交叉免疫过程中发挥作用。这些结果表明，H9N2 LAIV可用于控制鸡高致病性H5N2病毒。交叉免疫在一定程度上归功于LAIV 激活的H5N2 型交叉反应T细胞以及抗H5N2病毒的核蛋白（NP）的交叉绑定IgGs。
外文摘要：The most commonly utilized inactivated influenza vaccines (IIVs) are usually deficient in cross immunity against divergent viruses. On the other hand, live attenuated influenza vaccines (LAIVs) are proved to be more effective in cross-protective immunity. We previously developed a H9N2 LAIV and verified its effective protection against a broad spectrum of H9N2 strains. In the present study, we evaluated its cross-immunity against H5N2 virus, a representative subtype of currently predominant H5 highly pathogenic avian influenza viruses. All chickens vaccinated with this LAIV survived from challenge of H5N2 virus in a lethal dose, and viral proliferation was effectively inhibited, as well as pathological lesions. Vaccination of this LAIV significantly activated H5N2-reactive CD4(+) and CD8(+) T cells in lungs. These LAIV-activated cross-reactive T cells expanded robustly following H5N2 exposure, and the increasing tendency was temporally correlated with viral clearance. Besides cellular immunity, factors of humoral immunity also play a contributing role in cross-immunity. Passively transferring H9N2 LAIV anti-serum resulted in 100% survival rate to chickens against H5N2 virus. Within components of the anti-serum, cross-binding IgGs against nucleoprotein (NP) of H5N2 virus were found of a contributing role in the cross immunity. These results indicate that this H9N2 LAIV represents a promising strategy for controlling highly pathogenic H5N2 virus in chickens. The cross immunity was partly attributed to LAIV activated H5N2-cross-reactive T cells and partly attributed to cross-binding IgGs against NP.
外文关键词：Live attenuated influenza vaccine (LAIV)； Cross immunity； Non-neutralizing antibody； Cellular immunity； H9N2； Nucleoprotein (NP)
作者： Wang, MY；Wei, YD；Pu, J；Bing, GX；Sun, YP；Sun, HL；Wei, FH；Liu, JH
作者单位：中国农业大学
期刊名称：VETERINARY MICROBIOLOGY
期刊影响因子：2.65
出版年份：2018
出版刊次：7
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