整合禽网状内皮组织增殖病病毒基因的鸡痘病毒野毒株致病性研究  

Evaluation of the pathogenicity of a field isolate of fowlpox virus integrated with REV sequence

作　　者：孙洪磊[1] 车国喜[1] 秦梅[1] 杨凤[1] 李宏民[1] 刘思当[1] 

机构地区：[1]山东农业大学动物科技学院,山东泰安271018

出　　处：《中国兽医学报》2011年第11期1568-1572,共5页Chinese Journal of Veterinary Science

基　　金：山东省自然科学基金项目(31364)

摘　　要：以分离保存的整合禽网状内皮组织增殖病病毒(REV)基因的鸡痘病毒(FPV)野毒株接种CEF细胞,间接免疫荧光试验检测REV,结果未检测到游离REV病毒粒子;以该毒株人工感染7日龄SPF雏鸡,同时设阴性对照,常规免疫新城疫弱毒苗(ND)。接毒后每周采血动态检测NDV抗体、REV抗体、REV病毒血症;同时对试验鸡免疫器官指数、组织学变化动态观察,并对免疫器官的细胞凋亡动态检测。结果表明,整合REV基因的FPV感染后2周可引起鸡REV病毒血症,并产生REV抗体;导致中枢免疫器官发育分化不良,尤其对胸腺的影响最为明显,攻毒2周后,试验组与对照组相比,胸腺指数明显下降(P<0.05);免疫器官主要表现实质细胞数量少,正常结构发育不良,间质结缔组织增生而发生纤维化;细胞凋亡检测证实免疫器官的淋巴细胞和巨噬细胞均有明显的凋亡现象,细胞凋亡是引起免疫器官萎缩的主要原因。对新城疫疫苗免疫反应呈显著的抑制作用,攻毒3周后,试验组血清新城疫病毒抗体滴度显著低于对照组(P<0.05),其抗体滴度峰值低,维持时间短,下降速度快。本试验证实FPV整合REV前病毒基因组会明显改变FPV的致病性,表现某些REV的致病特征,使感染鸡REV抗体转为阳性并出现病毒血症,进一步证实REV可以通过基因组整合于FPV而进行传播的推测。CEF inoculated with one of the isolation FPV（FPV-SK）was negative for REV by IFA. Furthermore, SPF chickens were inoculated with the virus. Viraemia and antibody were dynamically detected in blood of inoculated chickens. After two weeks＇ infection,REV and antibody were consistently positive. The data suggested that in vivo testing of FPV by chick inoculation is a more sensitive test than in vitro testing in CEF. The histological changes, immune organs indexes,immune responses and cell apoptosis of the immune organs were dynamically observed. The results showed that the infection caused severe atrophy of central immune organs, especially in thymus. After two weeks＇ infection, thymus indexes in infected birds were significantly lower than that in the control birds （P〈0.05）. The immune organs revealed transient hyperemia, edema and gradually atrophy. The interstitial proliferation was also found. Its mechanism with apoptosis would be responsible for degenerative necrosis. The immune responses to ND vaccine were profoundly suppressed. In conclusion, the integration of FPV with REV gene can obviously change the pathogenicity and manifest some pathogenic characters of REV. REV provirus integrated into FPV provides additional transmission routes for the retrovirus by way of the infectious cycle of FPV.

关 键 词：鸡痘病毒 网状内皮组织增生症病毒 基因整合 免疫器官 细胞凋亡 

分 类 号：S852.65[农业科学—基础兽医学]