一种二点委夜蛾微孢子虫的致病机理

从二点委夜蛾幼虫体内首次分离到一种微孢子虫ED2013,用透射电镜观察了该微孢子虫感染二点委夜蛾幼虫后中肠的病理变化。结果发现寄主被感染后,中肠细胞微绒毛与杯状细胞的细胞质突起存在肿胀并掉落的情况;有些细胞核出现明显变形及膨大,或被挤压成长条状,细胞核内未发现微孢子虫侵入;部分线粒体略微肿胀变形,嵴的排列方向发生变化,随着感染时间延长而逐渐降解;细胞质中的粗面内质网上附着的核糖体脱落,后期感染严重阶段断裂成小段。染病后期的中肠细胞内充满微孢子虫,细胞质中的各细胞器均出现严重降解。根据研究结果并结合前人成果,认为该微孢子虫侵染二点委夜蛾的病理过程是从中肠细胞的病理变化开始并最终导致细胞破裂,逐渐扩大到寄主组织和器官,使其功能丧失,重者死亡。

Pathogenic Mechanism of a Microsporidium Strain Isolated from Athetis lepigone

A microsporidian was isolated from Athetis lepigone (M6schler) for the first time and the pathologic changes of infected midgut cells was observed by the transmission electron microscope.The results showed as follows:after infection,the microvilli of midgut cells and cytoplasm ecptoma of goblet cells became swelling and droped;obvious deformation,such as expansion and lengthen occurred in some of the cell nucleus,but no microspore was found in the nucleus;some of the mitochondria also became swelling and out of shape,and degraded in the late stage of infection,the ridges of them changed the arrangement as well;the rough endoplasmic reticulum broke into small pieces and the ribosome attached to them came off gradually.Microsporidia spreaded all over midgut cells at late stage of infection,all kinds oforganelles in cells degraded severely.According to the results and predecessors' achievements,we considered that the pathological process started with the changes of the midgut cells,led to cell rupture,extended to the host tissues and organs,lost their function and eventually death.