Molitor T W, Bautista E M, Choi C S
Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul 55108, USA.
Vet Microbiol. 1997 Apr;55(1-4):265-76. doi: 10.1016/s0378-1135(96)01327-2.
The immune system is a double-edged sword for porcine reproductive and respiratory syndrome virus (PRRSV) infection. On one edge PRRSV has a predilection for immune cells and the disease manifestations can be linked directly to changes in the immune system. PRRSV appears to replicate extensively, if not exclusively, in cells of the immune lineage, notably macrophages; the direct replication of which may lead to immunosuppression, precipitate secondary infection and/or mediate disease. On the other edge, the virus stimulates immunity post-infection that protects an animal from re-infection. A vast array of structural and functionally distinct antibody specific to PRRSV are generated following infection or vaccination. Discrete populations of functional antibodies appear at different times and possibly reflect reactivity to different PRRSV polypeptides. Cell-mediated immune responses specific to PRRSV can be detected in various exposed pigs as well. Thus, the immune system appears to be intimately involved in both the disease process and protection from disease. It is unclear at this state of understanding what immune compartment provides protective immunity. It is humoral (i.e. antibodies), selective functionally distinct populations of antibodies specific for selected PRRSV polypeptides or is cellular immunity essential for protection, or both. This review will attempt to summarize the current state of knowledge of the complex interaction of the immune system and PRRSV.
免疫系统在猪繁殖与呼吸综合征病毒（PRRSV）感染中是一把双刃剑。一方面，PRRSV倾向于感染免疫细胞，其疾病表现可直接与免疫系统的变化相关联。PRRSV似乎广泛（如果不是唯一地）在免疫谱系细胞中复制，尤其是巨噬细胞；其直接复制可能导致免疫抑制、引发继发感染和/或介导疾病。另一方面，病毒感染后会刺激免疫反应，从而保护动物免受再次感染。感染或接种疫苗后会产生大量结构和功能各异的针对PRRSV的抗体。不同功能的抗体群体在不同时间出现，可能反映了对不同PRRSV多肽的反应性。在各种暴露的猪中也能检测到针对PRRSV的细胞介导免疫反应。因此，免疫系统似乎与疾病进程和疾病防护都密切相关。在目前的认知状态下，尚不清楚哪个免疫区室提供保护性免疫。是体液免疫（即抗体）、针对选定PRRSV多肽的具有特定功能的选择性抗体群体，还是细胞免疫对保护至关重要，或者两者都必不可少。本综述将试图总结目前关于免疫系统与PRRSV复杂相互作用的知识现状。
