Virus-specific serum IgG, IgM, and IgA antibodies in cytomegalovirus mononucleosis patients as determined by immunoblotting technique.

The immune response to individual human cytomegalovirus (CMV) structural polypeptides was studied in paired sera from 15 adult CMV mononucleosis (CMV-MN) patients and healthy controls by immunoblotting technique (IB). IgM and IgG antibodies to at least 11 structural polypeptides with molecular weights of 28K, 49K, 55K, 57K, 66-70K, 82K, 87K, 110K, 150K, 205K, and 235K were detected in the patients' sera in the serum sample obtained in the acute phase of the disease. IgA antibodies to polypeptides with molecular weights of 66-70K, 82K, 110K, and 150K were also detected in these sera. In healthy seropositive adults, IgG antibodies with the same molecular weight polypeptides, excluding the 205K and 235K polypeptides, were detected as in convalescent CMV-MN patients. A prominent reactivity of IgM and IgA antibodies to the 66-70K and 150K polypeptides was noted in the acute sera from all the CMV-MN patients examined, but not in a number of late convalescent sera. The potential implications of these findings in the development of specific serological tests are discussed.