间接免疫酶组织化学法检测猪繁殖与呼吸综合征病毒感染和抗原定位

Antigen distribution and detection of porcine reproductive and respiratory syndrome virus(PRRSV) in infected piglets by the indirect immunohistochemistry method

以蔗糖密度梯度离心法提纯的猪繁殖与呼吸综合征(Porcine reproductive and respiratory syndrome,PRRS)病毒SC1株作为抗原,免疫家兔制备兔抗PRRS病毒IgG,成功建立了检测PRRS病毒抗原的间接免疫酶组织化学法。该方法只与PRRS病毒感染猪组织呈现阳性反应,与猪瘟病毒、猪细小病毒、猪伪狂犬病毒、猪乙脑病毒人工感染并致死仔猪的肝脏组织呈现阴性反应。用该方法检测PRRS SC-1株人工感染28日龄仔猪,在感染后7 d即可在肺门淋巴结、胸腺、扁桃体、十二指肠、肺、大脑和肾脏检测到PRRS病毒抗原。PRRS病毒抗原主要分布于胸腺和十二指肠感染细胞的胞浆内、肺门淋巴结小梁周围的淋巴窦和弥散的淋巴组织、扁桃体淋巴结的隐窝及其周边。该法具有特异、直观和敏感的特点,可用于PRRS病毒感染的实验室诊断、抗原定位及甲醛固定样本的回顾性诊断。

The anti-PRRSV IgG was obtained in rabbits after immunization against porcine reproductive and respiratory syndrome virus（PRRSV）SC-1 strain purified by sucrose density gradient centrifugal method,and indirect immnohistochemical methods（IIM） was successfully developed and standardized to detect the PRRSV antigen in PRRSV infected piglets.Special positive signals only emerged in the tissues of pigs infected by PRRSV,but positive signals did not emerge in the liver tissues from piglets infected with hog cholera virus,porcine parvovirus,porcine pseudorabies virus,porcine Japanese encephalitis virus without any positive signals.Seven days post infection,PRRSV antigen was detected in the hilar node,thymus,tonsil,duodenum,lung,cerebrum and kidney of the 28-day-old piglets artificially infected with PRRSV SC-1.PRRSV antigen distributed mostly in the cytoplasm of thymus and duodenum,lymph antrum and dispersed lymph of the hilar node,recess and its fringe of tonsil.IIM is a specific,sensitive and visual staining method.It can be applied to diagnose the porcine reproductive and respiratory syndrome（PRRS）,to detect the distribution of PRRSV antigen in tissues of the infected pigs,and in the reviewable diagnosis in formalin-fixed tissues.