主体内犀牛病毒在上下呼吸道的进化突出凸显了囊变异性和不依赖突变的分类
Negar Makhsous1, Stephanie Goya1, Carlos C Avendaño1
1Department of Laboratory Medicine and Pathology, University of Washington, Seattle, USA.
The Journal of infectious diseases
|July 24, 2023
概括
犀牛病毒 (RV) 可以在免疫功能低下的患者中从上呼吸道传播到下呼吸道,而不会进化. 在RV囊蛋白中的突变很常见,并且可以出现在未来的病毒序列中.
科学领域:
- 病毒学 病毒学
- 免疫受损宿主研究
- 呼吸道感染 呼吸道感染
背景情况:
- 犀牛病毒 (RV) 感染可以在免疫功能低下的人中从上呼吸道 (URT) 过渡到下呼吸道 (LRT),导致严重的肺炎.
- 在感染期间宿主内RV的进化动态在很大程度上仍然没有特征.
研究的目的:
- 在免疫功能低下的患者中调查RV的肠道进化.
- 确定是否需要基因适应,使RV从URT传播到LRT.
主要方法:
- 完整的RV基因组从12名造血细胞移植患者中进行了测序.
- 使用元基因组和amplicon下一代测序来追踪内部单核酸变异 (iSNVs).
- 在190天内,从URT (鼻洗) 和LRT (支气管支气管洗) 收集了样本.
主要成果:
- 在匹配的URT和LRT样本中发现了相同的RV种群,表明URT不需要适应LRT进展.
- 与非结构基因相比,编码iSNV在囊基因 (2.3倍) 中更为普遍.
- iSNVs经常位于囊表面残留物上,但不在已知的中和抗体表位上.
- 几年后,在社区序列中检测到来自免疫受损宿主的新出现的RV单元型.
结论:
- 在免疫受损宿主中,RV从URT向LRT的进展发生在没有特定的进化适应的情况下.
- RV囊蛋白表现出最高的变异性,并且在随后的病毒群体中可以发现新兴突变.
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