Cell-protective monoclonal antibodies to bovine enterovirus-3 and partial or no activity against other serotypes

Preparation of monoclonal antibodies to bovine virus diarrhea virus (BVDV) yielded some hybridoma cells that secreted monoclonal antibodies against the Madin-Darby bovine kidney cells. The anti-cellular monoclonal antibodies reacted with other bovine cells (bovine turbinate and testicle) but not with cell lines derived from other animal species. Subclones derived from one hybridoma partially blocked the infectivity of BVDV, possibly through the binding of the monoclonal antibodies with an epitope close to the receptor site of BVDV and not by way of steric hindrance. Unexpectedly, these same subclones completely blocked the infectivity of bovine enterovirus-3 (BEV-3) strain 240A and partially blocked the infectivity of BEV-2 and BEV-3 (ATCC strain) but not that of other serotypes. Other subclones derived from two other hybridomas, although cell membrane specific, did not have a protective activity against BEV or BVDV.