A peptide derived from cytomegalovirus (CMV) internal matrix protein pp65. CMV pp65 peptide antigen is used in recombinant vaccinia virus as an HLA-A-restricted epitope to produce vaccines and specific CD8+ and CD4+ cell responses against CMV infection, a serious complication of allogeneic bone marrow transplantation (BMT). In BMT, CMV infection may be prevented by passive immunization with donor-derived CMV-pp65-specific T-cell clones if provided early post-BMT. Check for active clinical trials using this agent. (NCI Thesaurus)