猪繁殖—呼吸综合征病毒的形态学

利用电子显微技术，对从上海某发病猪场分离到3株猪繁殖－呼吸综合征病毒（PRRSV）和标准美洲株（ATCC－VR2332）进行了形态特征的比较。结果表明，这4株病毒形态特征无显著差异。负染显示该病毒以球形为主，具有囊膜，囊膜上有纤突，大小为60－85nm。超薄切片可见病毒粒子大量存在于细胞浆内，有囊膜的直径为60－80nm，没有囊膜的直径为40－50nm，在细胞的线粒体，高尔基体和双基核膜内可见病毒粒子。在病毒增殖的同时，Marc-145细胞的显微结构逐渐发生破损，显示病毒的释放是通过破坏细胞膜结构的完整性来实现的。

Morphologic Study on Porcine Reproductive and Respiratory Syndrome Virus by Electron Microscopy

The morphology of porcine reproductive and respiratory syndrome virus isolated from Shanghai swine farms and ATCC-VR2332 strain were observed by electron microscopy(EM).The virus were sphere with diameter of 60-85 nm and had envelope with spike by negative stain under EM.Ultrathin section showed the virus replicated in cytoplasm and some organelles such as mitochondria,golgibody,nuclear membrane.Two types of virion were observed.One had envelope with diameter of 60-80 nm,another had no envelope with diameter of 40-50 nm.Meanwhile,the Marc-145 cells were damaged with virus replicating.So the virion release would lead in the destruction of integrated structure of the cell membrane.