人工感染雏鹅新型病毒性肠炎病毒的形态发生及宿主细胞的超微结构变化

Morphogenesis of Gosling New Type Viral EnteritisVirus and the Ultrastructural Changes of Tissues of Gosling Artificially Infected with the Virus

应用超薄切片及电镜观察发现,人工感染雏鹅新型病毒性肠炎病毒(goslingnewtypeviralenteritisvirus,NGVEV)后不同时间宰杀的及发病的雏鹅,其心、肝及小肠上皮细胞的细胞核(质)中均有典型腺病毒粒子。病毒侵害的靶器官主要是小肠粘膜上皮细胞,以上皮细胞微绒毛断裂、脱落开始,进一步发展为上皮细胞核畸形,固缩,核仁消失,核膜模糊和胞核崩解;胞浆严重空化,形成含有很多病毒粒子的"封入体";粗面内质网严重扩张呈囊状,其上的核蛋白体严重脱落;线粒体外膜破裂或嵴断裂及空化,部分受到损害的线粒体充满大量的病毒粒子;形成肠道栓子的外层假膜由大量的病毒粒子、细菌以及坏死的肠上皮细胞组成。肝和心的损害主要发生于感染早期,其粗面内质网和线粒体出现类似于小肠粘膜上皮细胞的变化。病毒在细胞核复制和装配,通过芽生或核膜的破裂而进入胞质,病毒于胞浆中主要是以"封入体"的形式存在,此外还有少量游离病毒。病毒释出细胞外可通过细胞膜芽生或破裂方式,也可通过与核外膜紧密联系的特殊膜性管道将病毒由胞核运至胞外。还讨论了小鹅瘟与雏鹅新型病毒性肠炎在超微结构上的区别。

The morphogenetic process of gosling new type viral enteritis virus(NGVEV)in vivo and the ultrastructural changes of its host cells were observed and analysed using electron microscopic techniques after Gosling had been infected by NGVEVThe investigation showed that the typical adenovirus virions could be found in the nucleus and cytoplasm of the infected heart?liver and small intestinal epithelial cells at different infection stagesThe target organ that virus attacked mainly was the small intestinal epithelial cellsIt began with microvilli break,then followed with nuclear deformity?condensation and disapperance,nuclear structure became unclear and the nucleus disintegratedThe vacuolar structure appeared in cytoplasm,the occlusion-body were formed in cytoplasm and a large amount of virions filled in itRough endoplasmic reticulum(RER)in the cytoplasm expanded heavily and a large amount of ribosomes dropped from itThe outer membrane of mitochondria(Mi)broke or inflated,cristae broke and disappeared,some damaged Mi were filled with large amount of virionsContents of the small intestine constisted of many bacteria,large amount of virions and a lot of scattered materials from necrotized and disintegrated epithelial cellsDamage of liver and heart occured mainly in early infection stageUltrastructural changes of RER and Mi were similar to those of small intestine epithelial cellsVirions replicated and matured in nucleus,they went out into cytoplasm by budding or nuclear breakOcclusion-body in cytoplasm was filled with large amount of virions and besides,a few of virions scattered in cytoplasmVirions went out of cells by budding or cells breakVirions also could be sent out of cells by special membrane tract which contacted closely with outer nuclear membrane