Immune Control of PRRS: Lessons to be Learned and Possible Ways Forward.
Immune Control of PRRS: Lessons to be Learned and Possible Ways Forward.
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DOI：
10.3389/fvets.2014.00002
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发表时间：
2014
影响因子：
3.2
通讯作者：
Razzuoli E
中科院分区：
文献类型：
--
作者：
Amadori M;Razzuoli E
猪繁殖与呼吸综合征（Porcine Reproductive and Respiratory Syndrome，PRRS）是一种由病毒致病性、猪品种易感性和表型、微生物感染压力和环境条件共同决定的宿主/病毒关系模型。该疾病可以通过农场管理计划来控制，该计划可以通过对动物进行疫苗接种或适应循环PRRS病毒（PRRSV）株来支持。然而，PRRS仍然是全球养猪业遭受重大损失的原因。免疫控制策略通常由于接种疫苗和感染动物的适应性免疫的不良和晚期发展而变得复杂。此外，有证据表明，实地试验的结果可能比在隔离设施中进行的实验研究的结果更差。中和抗体（NA）被证明可以预防PRRSV感染。相反，NA和适应性免疫在建立PRRSV感染后的病毒清除中的作用总体上仍然存在争议。猪最终消除了PRRSV感染，这可能与“受过教育的”先天免疫反应有关，这也可能在接种疫苗后发生。除了疫苗接种，免疫调节策略PRRS可以合理地主张在猪的“问题”农场，在那里的疾病流行和疾病相关的损失是迫切需要的实质性控制。这与疫苗接种并不矛盾，疫苗接种应优选限于前往PRRSV感染农场单位的无PRRSV动物。口服低剂量干扰素-α治疗在农场被证明对控制呼吸道和生殖道疾病爆发有效，而在隔离设施中结果不太清楚。考虑到PRRSV和细菌脂多糖之间对于呼吸道疾病发生的关键相互作用，低剂量I型干扰素对体外和体内观察到的炎症反应的强控制作用可能是田间试验中观察到的快速临床反应的基础。
Porcine reproductive and respiratory syndrome (PRRS) is an elusive model of host/virus relationship in which disease is determined by virus pathogenicity, pig breed susceptibility and phenotype, microbial infectious pressure, and environmental conditions. The disease can be controlled by farm management programs, which can be supported by vaccination or conditioning of animals to circulating PRRS virus (PRRSV) strains. Yet, PRRS still represents a cause of heavy losses for the pig industry worldwide. Immunological control strategies are often compounded by poor and late development of adaptive immunity in both vaccinated and infected animals. Also, there is evidence that results of field trials can be worse than those of experimental studies in isolation facilities. Neutralizing antibody (NA) was shown to prevent PRRSV infection. Instead, the role of NA and adaptive immunity on the whole in virus clearance after established PRRSV infections is still contentious. Pigs eventually eliminate PRRSV infection, which may be correlated with an “educated,” innate immune response, which may also develop following vaccination. In addition to vaccination, an immunomodulation strategy for PRRS can be reasonably advocated in pig “problem” farms, where a substantial control of disease prevalence and disease-related losses is badly needed. This is not at odds with vaccination, which should be preferably restricted to PRRSV-free animals bound for PRRSV-infected farm units. Oral, low-dose, interferon-α treatments proved effective on farm for the control of respiratory and reproductive disease outbreaks, whereas the results were less clear in isolation facilities. Having in mind the crucial interaction between PRRSV and bacterial lipopolysaccharides for occurrence of respiratory disease, the strong control actions of low-dose type I interferons on the inflammatory response observed in vitro and in vivo probably underlie the rapid clinical responses observed in field trials.