中文摘要：

用猪繁殖与呼吸综合征病毒（PRRSV）HB-2（sh）／2002滴鼻感染30日龄健康仔猪，分别于3、7、14、28、42天宰杀，用免疫组化法对呼吸道，泌尿道，生殖道和消化道的主要器官以及脑和主要淋巴器官中的病毒抗原进行了定位分析。结果表明，在各个时间段，病毒抗原阳性率最高的器官为呼吸道、消化道沿途的淋巴结，组织中的阳性细胞多数为巨噬细胞和树突细胞，从个别猪的脑、心肌、肝和呼吸道上皮的细胞检测到阳性信号，同时发现该毒株主要在巨噬细胞和呼吸道腺上皮细胞复制。

英文摘要：

Thirty day-old healthy piglets were nasally inoculated with PRRSV isolate HB-2 （sh）/2002. The piglets were killed at days 3, 7, 14, 28 and 42 post-inoculation, respectively. The distributions of PRRSV in the organs of respiratory, digestive, urinary and reproductive tracts were analyzed and localized by immunohistochemistry assay. The organs showing the highest positive rate of PRRSV antigen were lymph notes along the respiratory and digestive ducts. Macrophages and dendritic cells in multiple tissues showed to be positive. The positive signal could be observed in individual neurons, epithelial cells of respiratory tract, hepatocytes, and cardiocytes. Meanwhile it was found that PRRSV HB-2 （sh）/2002 proliferated mainly in both macrophages and glandular epithelium.