应用原位PCR对鸡传染性法氏囊病病毒早期侵染过程的研究

Study on the Early Infecting Process of Infectious Bursal Disease Virus in Chicken by in situ RT-PCR

人工接种 35日龄SPF鸡传染性法氏囊病病毒 ,间隔不同时间采集法氏囊、胸腺、脾、盲肠扁桃体、肾、肝和腿肌进行了原位PCR检测 ,同时观察各组织病理变化。结果无论是H毒株还是Ts毒株 ,接种后 4h肝、肾、脾等组织中即出现明显的阳性信号 ,Ts毒株 4hPI从胸腺、盲肠扁桃体、腿肌等组织中也检出了病毒基因序列。接种H毒株和Ts毒株后 2 8h和 40h ,法氏囊淋巴细胞开始出现变性、坏死。在阳性信号检出的时间上 ,法氏囊较肝、肾、脾等组织是滞后的。H毒株较Ts毒株在早期对法氏囊具有更强的侵染能力。

The bursae, livers, nephridia, spleens, thymus glands, cecal tonsils and muscles were harvested at 4, 8, 16, 28, 40, 56, 72, 96h post-infection(PI) respectively, after two infectious bursal disease virus(IBDV)strains were inoculated into 5 week-old specific-pathogen-free chickens. IBDV were detected from these samples by in situ RT-PCR and at the same time the pathological changes of these tissues were investigated. The results showed that typical positive signals were discovered from livers, nephridia and spleens of either vvIBDV H strain or cell-adapted Ts strain infection at 4h PI. Viruses were also found in thymus gland, cecal tonsil and muscle of Ts strain infection at 4h PI. Decrement of bursal lymphocytes was observed at 28h PI for H strain and 40h PI for Ts strain infection respectively. Positive signals were observed in the bursa after their appearance in the liver, nephridium and spleen. H strain manifested more violent attacking capability than Ts strain. The sensitivity of the viral detection by in situ PCR is very high.