重复犯罪者:从整个基因组的角度来看,PRRSV-2的临床复发
Julia P Baker1, Albert Rovira2, Kimberly VanderWaal1
1Animal Science/Veterinary Medicine 385, 1988 Fitch Ave., St. Paul, MN 55108, United States.
Veterinary microbiology
|February 7, 2025
概括
猪繁殖和呼吸系统综合征病毒 (PRRSV) 在母猪养殖场的反复爆发可能源于结构蛋白的病毒进化,特别是糖蛋白外. 这种微观进化使得PRRSV能够逃避免疫力,导致持续的临床疾病.
科学领域:
- 兽医病毒学 兽医病毒学
- 动物免疫学 动物免疫学
- 分子流行病学分子流行病学
背景情况:
- 猪生殖和呼吸系统综合征病毒 (PRRSV) 在母猪养殖场的临床再爆发是一个重大的经济和动物健康挑战.
- 尽管假定免疫力,但使PRRSV持久性和重复爆发的机制尚不清楚.
研究的目的:
- 系统地确定母猪养殖场的临床复发病例.
- 评估重新断裂与糖蛋白ectodomains中的病毒进化相关的假设.
- 为了确定特定的氨基酸部位可能参与免疫逃避.
主要方法:
- 从再爆发事件中分离的病毒的全基因组测序.
- 病毒基因组的对比比较,以确定氨基酸差异.
- 对结构蛋白中的氨基酸位点变异的分析,重点是糖蛋白质ectodomains.
主要成果:
- 结构蛋白中的多个氨基酸位点经常在重新破裂的病毒分离物之间存在差异.
- 在GP5的几个部位显示出高于预期的变化,这表明免疫选择.
- 在GP2,E,GP3和GP4的ectodomains中也观察到变化,这表明免疫规避的多基因基础.
- 大多数确定的部位 (68%) 位于ectodomains上,其中75%的GP5部位与抗体中和逃脱有关.
结论:
- 在PRRSV结构蛋白域内发生的微进化变化,特别是GP5,可能有助于免疫逃脱和抗体中和规避.
- 这些抗原变异使关闭等群体管理策略复杂化,导致持续的临床爆发.
- 识别这些关键的氨基酸位置有助于理解PRRSV的持久性和制定有针对性的干预措施.
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