Immunoglobulin A and M patterns to human cytomegalovirus during recurrent infection in patients with AIDS using a modified western blot

Abstract

Immunoglobulin A and M patterns to human cytomegalovirus (HCMV) were investigated in sera from actively HCMV infected AIDS patients (n = 61) and healthy HCMV seropositive controls (n = 28) by a Western blot method (modi-blotting) and ELISA. The Western blot showed a higher detection rate for both IgA (78.7% vs. 52.5%) and IgM (83.6% vs. 13.1%) than ELISA in the immunocompromised patients suffering from active HCMV infection. Of the healthy seropositive individuals, 35.7% and 21.4% had a weak positive IgA- and IgM-class antibody reactivity respectively with HCMV-specific bands in the immunoblot. Immunoglobulins M and A were not detected by ELISA in the healthy control group. Immunoreactions in this group were restricted to viral polypeptides with M(r) of 68 kDa and 123 kDa. Additional bands were found in the actively infected patients only and were observed more frequently with IgA than IgM (47.5% vs. 29.5%). Results from the present study indicate, that using a sensitive Western blot technique, a higher serologic detection rate of active recurrent infection is achieved in AIDS patients. Nevertheless, immunoglobulin A and M are detected in a certain percentage of HCMV-seropositive healthy individuals not suffering from active HCMV infection. Broader immune reactions of HCMV-IgA as determined by HCMV Western blot assay are associated with an active infection, but were not present in all the actively infected patients.