SAM-P1鼠对神经毒型流感病毒R404BP株中枢神经系统感染的免疫防御

Immune defence to neurovirulent recombinant influenza A virus in the senescence-accelerated mouse

目的:研究SAMP1鼠中枢神经系统被流感病毒感染后,机体对感染神经元的清除及病毒感染所诱导的免疫应答。方法:采用立体定位微量注射法,用神经毒型流感病毒R404BP株经嗅球感染SAMP1鼠,造成实验性流感病毒脑炎动物模型。检测感染鼠生存率,感染神经元清除时间以及Th1型细胞免疫。结果:SAMP1鼠对流感病毒R404BP株易感性高,感染后生存率降低,清除感染神经元所需时间延长,脾淋巴细胞NK活性及CTL杀伤活性低下。结论:老化鼠因机体Th1型免疫应答下降导致对神经毒型流感病毒免疫防御机制的降低。

Objective:To investigate the immune defence against acute encephalitis induced by the highly neurovirulent recombinant R404BP strain of influenza A virus.Methods:A murine model system for a lethal encephalitis due to influenza has been established by stereotaxic microinjection with the recombinant R404BP strain of influenza A virus into the olfactory bulb of the senescence-accelerated mouse(SAM) strain P1 mice. The mortality of infected mice, clearance of infected neurons and induced cellular immune responses were investigated.Results:The SAM-P1 mice showed a higher rate of mortality with prolonged virus shedding. The increased susceptibility was associated with impaired activity of both NK cells and virus-specific cytotoxic T lymphocytes.Conclusion:The decreased Th1 immune responses in the senescence-accelerated mouse might be responsible for the low defence system against neurovirulent recombinant influenza A virus.