4种有囊膜RNA病毒形态发生的比较观察

Comparison and observation of four envelope RNA viruses in morphogenesis

目的从形态结构及形态发生角度准确区分和确认流感病毒、犬冠状病毒、狂犬病毒和新城疫病毒。方法将感染4种RNA病毒的体外培养细胞用戊二醛、锇酸固定,制成超薄切片,透射电镜观察。结果4种病毒子代病毒的核衣壳或完整病毒粒子的装配都在胞浆中进行,子代病毒装配的前体物质的形态结构不同。4种病毒子代病毒的完整病毒粒子装配的形式不同,其中流感病毒和新城疫病毒只在细胞膜以向胞外出芽的方式装配成完整病毒粒子;狂犬病毒在细胞浆膜相结构和细胞膜表面以出芽方式装配成完整病毒粒子;冠状病毒在细胞浆膜相结构以出芽方式装配成完整病毒粒子。流感病毒子代病毒装配完即离开细胞膜;新城疫病毒的子代病毒不易离开细胞膜。多数狂犬病毒和冠状病毒的子代病毒要待细胞破碎后才能释放到细胞外。结论利用病毒培养物的超薄切片进行电镜观察,可根据其形态发生准确区分4种RNA病毒。

Objective To observe and discriminate four RNA viruses by the morphogenesis, including avian influenza virus, canine coronavirus, rabies virus and newcastle disease virus. Methods Infected cells by four RNA viruses were treated according to the preparation and observation of specimens for transmission electron microscopy. Results The nucleocapsids and/or viral particles of four viruses were all assembled in cytoplasm, but there were different in the precursor structure and assembly manner of viral particles among four viruses. Budding from the cytoplasmic membrane was only assembly and proliferation manner of influenza virus and new castle disease virus. But rabies virus was assembled and reproduced by means of buds in membranous structure and cytoplasmic membrane, and reproduction of coronavirus was in membranous structure. After the completion of assembly, influenza virus detached from the cytoplasmic membrane immediately. However, progeny viruses of rabies virus and coronavirus were not released until cell lysis, and progeny virus of newcastle disease virus was not remove from cytoplasmic membrane easily. Conclusion Transmission electron microscopy for the viral culture can be used to discriminate above RNA viruses by the morphogenesis.