Immunoglobulin G subclasses and lymphocyte stimulatory responses to cytomegalovirus in transplant patients with primary cytomegalovirus infections.

The early activation of T- and B-cell responses to cytomegalovirus was studied in immunosuppressed patients. Primary lymphocyte stimulation to cytomegalovirus (CMV) antigen, a measure of T-helper activity, and anti-CMV IgG subclass responses were analyzed. Ten patients suffering from primary CMV infection following renal transplantation were studied. Of the ten, nine became positive for CMV induced lymphocyte proliferation 5-40 weeks after transplantation. Nine showed an almost simultaneous appearance of anti-CMV IgG1 and three at 3-32 weeks after transplantation, while one patient synthesized only low levels of anti-CMV IgG1. The lymphocyte proliferation assays have limited diagnostic value for primary CMV infection in renal transplant patients. The humoral and cellular immune responses seemed to be independent of each other.