Establishing the Reactivity of Monoclonal Antibodies against Porcine Endogenous Retrovirus Envelope Protein

Xenotransplantation of pig organs may be associated with a risk of transmission of microorganisms. Porcine endogenous retroviruses (PERV) are of particular concern since in vitro experiments have demonstrated that human cells are susceptible to such microorganisms. To monitor the transmission of PERV, highly sensitive and specific immunoassays must be developed for clinical surveillance. This report describes the production, preliminary characterization and application of a monoclonal antibody (mAb) against a recombinant PERV envelope (Env) protein. The generated mAb was tested using recombinant PERV Env protein expressed in Escherichia coli, purified PERV virus particles and human 293 cell line infected with PERV. PERV-translated proteins of 15, 70 and 85 kD were recognized specifically using PERV-8E10 mAb and Western blotting. No cross-reactivity was demonstrated with exogenous viral protein (HIV, HTLV and MuLV). Moreover, PERV-8E10 mAb can be applied to localize PERV proteins using an immunoperoxidase assay. This work reveals that recombinant PERV Env protein and mAb may be effective in detecting antibodies against PERV in xenotransplanted patients, or for butchers who have extensive contact with pigs.