AUTHOR=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 TITLE=Development of a Monoclonal Antibody Against Porcine CD163 SRCR5 Domain Which Partially Blocks Infection of PRRSV JOURNAL=Frontiers in Veterinary Science VOLUME=7 YEAR=2020 URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2020.597843 DOI=10.3389/fvets.2020.597843 ISSN=2297-1769 ABSTRACT=

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 497TWGTVCDSDF506, 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.