Development of a Monoclonal Antibody Against Porcine CD163 SRCR5 Domain Which Partially Blocks Infection of PRRSV

• Published in: Frontiers in veterinary science 2020-11, Vol.7, p.597843-597843
• Main Authors: Zhang, Yujiao, Zhang, Kuan, Zheng, Hao, Liu, Changlong, Jiang, Yifeng, Du, Nannan, Li, Liwei, Li, Guoxin, Yu, Lingxue, Zhou, Yanjun, Tong, Wu, Zhao, Kuan, Tong, Guangzhi, Gao, Fei
• Format: Article
• Language: English
• Subjects: CD163; epitope; monoclonal antibody; PRRSV; SRCR5; Veterinary Science
• ISSN: 2297-1769; 2297-1769
• DOI: 10.3389/fvets.2020.597843

Porcine reproductive and respiratory syndrome virus (PRRSV), which seriously endangers the world pig industry, invades host cells through receptor-mediated endocytosis involving clathrin. CD163 is an essential receptor for PRRSV during its infection of cells. The scavenger receptor cysteine-rich 5 (SRCR5) domain of the CD163 molecule is necessary for PRRSV infection, and interacts with glycoproteins GP2a and GP4 of PRRSV, allowing the virus to infect the host cells. In this study, a monoclonal antibody (mAb) against the SRCR5-6 region of porcine CD163 was developed, and the target epitope of the mAb was determined as 497 TWGTVCDSDF 506 , which is directly adjacent to the ligand-binding pocket (LBP) domain (487-495aa) of CD163. Further study indicated that the mAb could partially block PRRSV infection of its target cells, pulmonary alveolar macrophages. The mAb developed in the study may provide a foundation of antiviral therapy for PRRSV.