Preparation of Monoclonal Antibodies Against the gD Protein of Feline Herpesvirus Type-1 by mRNA Immunization

This study aimed to develop monoclonal antibodies (mAbs) against the gD protein of FHV-1 for rapid and specific virus detection. The gD protein, a highly conserved part of the FHV-1 envelope, is crucial for viral entry into host cells, making it an ideal detection target. We immunized BALB/c mice with an mRNA vaccine encoding the gD gene, achieving a serum antibody titer of 1:140,000 after three immunizations. The mice were then boosted with recombinant gD protein. Through cell fusion and multiple subcloning rounds, we obtained five hybridoma cell lines (D7, E4, E9, E10, and E19) that stably secrete anti-gD protein mAbs. Characterization by indirect immunofluorescence and Western blot showed that mAbs D7 and E4 have high specificity and strong binding activity against FHV-1, detectable at 2 μg/mL. These mAbs provide specific tools for FHV-1 detection and a basis for developing rapid diagnostic methods using ELISA, colloidal gold, and other technologies.