Nielsen J, Bøtner A
Danish Veterinary Institute for Virus Research, Kalvehave, Denmark.
Vet Microbiol. 1997 Apr;55(1-4):289-94. doi: 10.1016/s0378-1135(96)01334-x.
4 1/2-month old SPF pigs were experimentally infected with PRRS virus. Blood samples were collected with regular intervals up to day 35 post inoculation (PI). Serum was used for PRRS virus isolation and antibody detection and stabilized blood for total leucocyte counts, differential counts and characterization of lymphocyte subpopulations by flow cytometry analysis using monoclonal antibodies specific for porcine CD2, CD4 and CD8. After an initial viremic period of 1-7 days duration for individual pigs, PRRS virus was intermittently detected in pigs up to day 18 PI. All pigs had developed antibodies against PRRS virus by day 14 PI. Total blood leucocyte counts and lymphocyte counts were significantly decreased for a few days shortly after infection, but had returned to pre-infection levels on day 8-10 PI. A major change in the distribution of lymphocyte subpopulations was observed on day 3 PI, where the percentages of CD2+, CD4+ and CD8+ cells were significantly decreased. However, the percentages of these lymphocyte subsets quickly returned to approximately pre-infection values. The observed changes of the parameters examined do not indicate long-term systemic immunosuppression of the infected pigs.
4个半月大的无特定病原体（SPF）猪被实验性感染猪繁殖与呼吸综合征病毒（PRRS病毒）。在接种后（PI）长达35天的时间内定期采集血样。血清用于PRRS病毒分离和抗体检测，抗凝全血用于白细胞总数计数、分类计数以及使用针对猪CD2、CD4和CD8的单克隆抗体通过流式细胞术分析对淋巴细胞亚群进行表征。在个体猪最初持续1 - 7天的病毒血症期后，在接种后第18天之前，猪体内间歇性检测到PRRS病毒。到接种后第14天，所有猪都已产生针对PRRS病毒的抗体。感染后不久，全血白细胞计数和淋巴细胞计数在几天内显著下降，但在接种后第8 - 10天恢复到感染前水平。在接种后第3天观察到淋巴细胞亚群分布的主要变化，其中CD2 +、CD4 +和CD8 +细胞的百分比显著下降。然而，这些淋巴细胞亚群的百分比很快恢复到接近感染前的值。所观察到的检测参数变化并不表明感染猪存在长期的全身免疫抑制。
