A panel of 13 monoclonal antibodies (MAbs) was produced that detect B virus (BV) proteins. Several of these MAbs were highly specific for BV, while the remainder cross-reacted in varying degrees with the other primate alphaherpesviruses. Utilizing western blot and radioimmunoprecipitation analysis, the MAbs were found to detect at least four distinct BV-infected cell antigens, several of which were composed of multiple polypeptides. One target antigen has been identified as the BV glycoprotein B (gB) homologue and was recognized by both virus-specific and cross-reactive MAbs. Although gB is an essential protein, none of the anti-gB MAbs neutralized infectious virus.