Kaposi's sarcoma: immunoperoxidase staining for cytomegalovirus

An immunoperoxidase technique was used to test for cytomegalovirus (CMV) proteins in lesions of Kaposi's sarcoma from 19 patients with acquired immune deficiency syndrome (AIDS) and 3 patients without AIDS. CMV proteins could not be detected in any of the cases of Kaposi's sarcoma. Thus, while CMV genetic material may be present in these cells, the virus is not actively directing the synthesis of proteins. This eliminates reactivation of latent CMV in tumor tissue, or late infection of Kaposi's sarcoma cells as explanations for the elevated antibody titers to CMV and other evidence of CMV infection in patients with Kaposi's sarcoma. However, the possibility remains that exposure to CMV occurs as a primary event in the development of Kaposi's sarcoma. These findings indicate that, as in Kaposi's sarcoma of the elderly, the virus is inactive in Kaposi's sarcoma cells of patients with AIDS, and there is no difference between the two lesions in immunoperoxidase staining for CMV proteins.