CYTOMEGALOVIRUS-SPECIFIC T-CELL IMMUNITY IN RECIPIENTS OF AUTOLOGOUS PERIPHERAL-BLOOD STEM-CELL OR BONE-MARROW TRANSPLANTS

The cytomegalovirus (CMV)-specific CD8(+) cytotoxic T-lymphocyte (CTL) and CD4(+) T-helper cell (Th) functions were characterized in 15 CMV seropositive recipients of autologous peripheral blood stem cell or bo ne marrow transplants. These immune functions were evaluated in periph eral blood specimens obtained before and at 1, 2, and 3 months after t ransplant. For study of CTL activity, blood mononuclear cells were coc ultured with CMV-infected autologous fibroblasts for 2 weeks and then tested for cytotoxicity against CMV-infected or mock-infected autologo us and HLA-mismatched fibroblasts. The Th response to CMV antigen was assessed by standard lymphoproliferative assay, CMV-specific CD8(+) CT L and CD4(+) Th responses were detectable in 12 (80%) and 14 (93%) pat ients, respectively, in the first 3 months after transplantation. A Th response to CMV was always present by the time of first CTL detection . During the posttransplant period, CMV infection occurred in 6 (40%) patients, and detection of CMV-specific CD8(+) CTL activity was associ ated with protection from subsequent CMV infection (P = .002). Among C MV seropositive autograft recipients, CMV-specific CD8(+) CTL and CD4( +) Th responses are restored in a large proportion of patients in the first 3 months after transplantation, and the presence of a specific C D8(+) CTL activity affords protection from CMV infection. (C) 1997 by The American Society of Hematology.