致病性鹅源新城疫病毒对鸡胚成纤维细胞的致病变特性

选择4株鹅源新城疫病毒(NDV)接种鸡胚成纤维细胞(CEF)培养物,研究鹅源NDV对CEF的致病变特性,并与鸡源及鸽源NDV进行比较。结果显示,鹅源NDV接种次代CEF后24h开始有病变产生,表现为少数细胞变圆、皱缩,折光性增强,随后病变缓慢进展,感染细胞形成大量合胞体,到84～144h时,CEF单层彻底破坏;鸡源和鸽源MDV接种CEF后也在24h左右开始有病变产生,最初病变与鹅源毒株导致的病变相似,但病变进展迅速,细胞显著裂解并导致单层的严重破坏,60～84h时细胞单层即彻底破坏。对病毒接种后不同时间段培养物上清血凝(HA)效价的测定结果表明,鹅源NDV接种后84～120h培养物上清HA效价达到高峰,为5～8 log2,鸡源和鸽源NDV接种后60～84h HA效价即可达到高峰,但其最高效价只有4 log2。

Cytopathic Alterations of Chicken Embryo Fibroblasts Induced by Newcastle disease virus of Goose Origin

The cytopathic effects on chicken embryo fibroblasts (CEFs), induced by Newcastle disease virus (NDV) derived from the novel disease outbreaks in geese during 1997 - 2000, were compared with those induced by chicken and pigeon isolates. When the CEFs were inoculated with goose isolates, cell abnormalities could be seen as early as 24 h PI, characterized by occurrence of some rounded,refractile and dark appearing cells. Then the lesions became more severe gradually, with a large number of syncytial cells appeared. The CEF monolayers were destroyed completely at 84-144 h PI, and the HA titers in the culture supernatants could get as high as 5-8 log2. When infected with ND viruses of chicken or pigeon origin, the earliest cell lesions were observed at 24 h PI, too. But it appeared that the alterations developed more rapidly in this occasion. The cells became rounded and refractile and necrosized, leaving empty areas (holes) in the cell sheet. At 60-84 h PI, the monolayers destroyed, with HA titers of 3-4 log2 in the culture supernatant. The syncytial cells contained far less nuclei than those formed after inoculation of goose isolates.