Protective immunity in cattle following vaccination with conventional and marker bovine herpesvirus-1 (BHV1) vaccines

The efficacy of two experimental subunit go vaccines and two commercial whole virus vaccines was determined in a bovine herpesvirus-1 (BHV1) challenge trial. Full-length go and a truncated secreted form of go (tgD) were produced using a vaccinia virus expression system and purified by affinity chromatography. Comparison of these forms of go did not reveal significant structural or antigenic differences. Calves immunized with go or tgD in avridine developed significantly (P<0.05) higher neutralizing antibody titers in the serum and nasal mucosa than animals vaccinated with killed virus (KV) or modified live virus (MLV). Following challenge with BHV1, all vaccinated calves had significantly, (P<0.05) lower rectal temperatures and clinical scores than those in the placebo group. rn contrast to the KV-, MLV- and placebo-vaccinated calves, the go and tgD-immunized animals experienced minimal weight loss and virus shedding post-challenge. Glycoprotein B-specific antibodies were detected in KV- and MLV-vaccinated calves, but not in gD- or tgD-immunized animals. These data suggest that full-length or truncated go, when formulated in an appropriate adjuvant, is more effective than two KV and MLV vaccines and may be used as a marker vaccine for concurrent vaccination and eradication programs of BHV1. Copyright (C) 1997 Elsevier Science Ltd.