Abstract
We have produced a monoclonal antibody against human cytomegalovirus (HCMV) which recognizes a structural protein of 28 000 mol. wt. which is present in both the cytoplasm of infected cells during the late phase of the viral replication cycle and in the extracellular viral particles. This antigen was detected in all HCMV strains assayed and reacted with human sera having anti-HCMV antibodies.