ANTIGENIC DIFFERENCES BETWEEN A FIELD ISOLATE AND VACCINE STRAINS OF BOVINE VIRAL DIARRHEA VIRUS

Antigenic diversity among the bovine viral diarrhea virus (BVDV) cytop athic strains 87-2552 (field isolate) and NADL and Singer (prototype s trains) was demonstrated with monoclonal antibodies (MAbs) in enzyme-l inked immunosorbent, immunofluorescence, virus neutralization, and imm unoprecipitation assays, Two MAbs against BVDV strain 87-2552, designa ted D11 and B7, strongly neutralized this field strain and were specif ic for the 48-kDa glycoprotein of the virus. These two MAbs have diffe rent subisotypes, immunoglobulin G1 for D11 and immunoglobulin G3 for B7, MAbs against BVDV strains 87-2552 and NADL were specific for their respective strains in virus neutralization assays. The results indica ted significant antigenic differences between BVDV strain 87-2552 and the NADL and Singer strains.