Cell-mediated immunity to cytomegalovirus in patients receiving immunosuppressive therapy

Employing the techniques of complement-fixation (CF), immunofluorescence (IF), and in vitro lymphocyte transformation (LTF), the humoral antibody response and cell-mediated immune (CMI) response to cytomegalovirus (CMV) were studied in the serum and peripheral blood lymphocytes in 19 normal children (controls) and 23 patients with renal disease who were receiving immunosuppressive therapy or undergoing hemodialysis. The LTF activity was determined by the whole blood microassay using two strains of CMV (AD-169 and Davis) and phytohemagglutinin (PHA). The antibody level responses to CMV in different groups of subjects were generally similar. The LTF response to PHA as evidenced by delta cpm activity was moderately depressed in immunosuppressed and hemodialyzed subjects compared to the response observed in the controls. The mean delta cpm activities in response to AD-169 and Davis strains of CMV in seropositive immunosuppressed patients were about one-fifth and one-third lower respectively than those of seropositive normal controls. These observations suggest that an impairment of CMV specific cellular immunity may be an important mechanism underlying the increased susceptibility to CMV infections in patients with chronic renal disease who receive immunosuppressive therapy.