Most virus-specific polypeptides in cells productively infected with Marek's disease virus or herpesvirus of turkeys possess cross-reactive determinants.

Most virus-specific polypeptides in cells productively infected with Marek's disease virus (MDV) or herpesvirus of turkeys (HVT) possess cross-reactive antigenic determinants, although the two viruses have very little DNA homology. The cross-reactivity appeared to be more evident when [35S]methionine-labelled polypeptides were immunoprecipitated than when the [3H]glucosamine-labelled polypeptides were immunoprecipitated, suggesting that the glycoproteins of MDV and HVT may be less related in structure than other proteins. The major cross-reactive glycoproteins excreted into the culture mediums of MDV- and HVT-infected cells had molecular weights of 64 000 (gp64) and 56 000 (gp56) respectively.