Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, KS, USA.
Division of Animal Science, University of Missouri, Columbia, MO, 65211, USA.
Virology. 2020 Feb;541:136-140. doi: 10.1016/j.virol.2019.12.007. Epub 2019 Dec 24.
The coronaviruses, porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), and porcine deltacoronavirus (PDCoV) represent important sources of neonatal diarrhea on pig farms. The requirement for aminopeptidase N (APN) as a receptor for TGEV, but not for PEDV, is well established. In this study, the biological relevance of APN as a receptor for PDCoV was tested by using CRISPR/Cas9 to knockout the APN gene, ANPEP, in pigs. Porcine alveolar macrophages (PAMs) from ANPEP knockout (KO) pigs showed resistance to PDCoV infection. However, lung fibroblast-like cells, derived from the ANPEP KO PAM cultures, supported PDCoV infection to high levels. The results suggest that APN is a receptor for PDCoV in PAMs but is not necessary for infection of lung-derived fibroblast cells. The infection of the ANPEP KO pigs with PDCoV further confirmed that APN is dispensable as a receptor for PDCoV.
冠状病毒、猪流行性腹泻病毒（PEDV）、传染性胃肠炎病毒（TGEV）和猪德尔塔冠状病毒（PDCoV）是猪场仔猪腹泻的重要病原体。APN 作为 TGEV 的受体，但不是 PEDV 的受体，这一点已得到充分证实。在这项研究中，通过使用 CRISPR/Cas9 敲除猪的 APN 基因（ANPEP）来测试 APN 作为 PDCoV 受体的生物学相关性。来自 ANPEP 敲除（KO）猪的肺泡巨噬细胞（PAMs）对 PDCoV 感染具有抗性。然而，源自 ANPEP KO PAM 培养物的肺成纤维样细胞能够支持 PDCoV 的高水平感染。结果表明，APN 是 PAMs 中 PDCoV 的受体，但对于肺源性成纤维细胞的感染不是必需的。PDCoV 感染 ANPEP KO 猪进一步证实 APN 作为 PDCoV 的受体是可有可无的。
