Preparation and Identification of a Monoclonal Antibody against the Pseudorabies Virus gE Glycoprotein through a Novel Strategy

SIMPLE SUMMARY: Porcine pseudorabies is a virulent infectious disease of domestic and wild animals caused by pseudorabies virus. Especially since 2011, the prevalence of mutant strains in China has caused severe economic losses to its breeding industry. As a marker protein, gE glycoprotein can distinguish wild strains from vaccine strains. Therefore, we are committed to obtaining a monoclonal antibody against the gE glycoprotein. We are also studying its characteristics to further explore its application value. In this study, we used a novel immunization and screening strategy to prepare a monoclonal antibody and obtained the monoclonal antibody 1H5 against the gE glycoprotein. An indirect immunofluorescence assay revealed that this monoclonal antibody was specific to both classic and variant strains of pseudorabies virus. Subsequently, we identified the linear epitopes of B cells recognized using the monoclonal antibody. The monoclonal antibody 1H5 bound at (67)RRAG(70), which is a novel epitope and is conserved in almost all pseudorabies virus strains. This study provides a new idea for the preparation of monoclonal antibodies. ABSTRACT: Since 2011, pseudorabies virus (PRV) has recurred in several vaccinated pig farms in China. PRV variants with high virulence were found to be the main cause of the outbreaks. In the face of the PRV epidemic, detection of the wild strain is as important as vaccine immunization, so we hoped to achieve differential diagnosis of PRV by obtaining a monoclonal antibody (mAB) that could be used to identify the wild strain. In this study, we used a novel immunization and screening strategy to prepare an mAB and obtained mAB 1H5 against the gE glycoprotein. An immunofluorescence assay (IFA) revealed that this mAB was specific to both classic and variant strains of PRV. Subsequently, we further identified the linear epitopes of B cells recognized using the mAB. The mAB 1H5 bound at (67)RRAG(70), which is a novel epitope and is conserved in almost all PRV strains. These findings provide novel insight into the structure and function of PRV proteins, the analysis of antigenic epitope characteristics, and the establishment of antigen or antibody detection methods.