Preparation and Characterization of Polyclonal Antibodies against Porcine Enterovirus G (EV-G) 3C Protein for Diagnosis and Functional Study

Porcine enterovirus G (EV-G) is a small RNA virus belonging to the Enterovirus genus within the Picornaviridae family. While EV-G infection in pigs is usually asymptomatic, it can contribute to diarrhea when present alongside other gastrointestinal viruses. The recent discovery of naturally recombinant PLP genes in EV-G strains across various countries necessitates the development of effective diagnostic tools.

This study focused on generating and characterizing polyclonal antibodies against the 3C protein of the EV-G-PLP strain. The recombinant plasmid pET-32a-EV-G-PLP-3C was constructed and expressed in BL21 (DE3) cells to produce the 3C protein. After purifying the protein, researchers immunized New Zealand rabbits to obtain polyclonal antibodies. The antibody specificity and potency were assessed using indirect ELISA, indirect immunofluorescence assay, and Western blot.

Results showed that the 3C protein primarily existed as inclusion bodies with a relative molecular mass of approximately 38.8 kDa. The polyclonal antibodies demonstrated high specificity and reactivity towards the 3C protein. Furthermore, animal experiments using ICR mammary mice provided insights into the infectivity of the EV-G-PLP strain.

This study provides valuable tools for the diagnosis of EV-G-PLP infection and lays the groundwork for further investigations into the biological function of the 3C protein.