Correlation of viral load in the blood and reconstitution of HCMV-specific, HLA-A*0201– and HLA-B*0702–restricted CTLs in 2 patients after allogeneic SCT.

Peptide-specific CD8⁺ CTLs were analyzed by intracellular IFN-γ staining with flow cytometry after specific stimulation, and viral load was assessed by quantitative PCR. Black bars indicate HLA-A*0201–restricted CTLs and gray bars HLA-B*0702–restricted CTLs; the black line and open diamonds represent viral load. Early reconstitution of predominantly HLA-A*0201–restricted CTLs in patient 1 was associated with complete suppression of HCMV replication after allogeneic SCT (A). Patient 9, who was given a transplant of highly purified stem cells from a 1-Ag–mismatched family member (A3 A2), showed early reconstitution of HLA-B*0702–restricted CTLs associated with rapid clearance of the viral DNA from the blood (B). However, HLA-A*0201–restricted CTLs were detectable just above the lower detection limit on 2 occasions. Values are the absolute numbers of peptide-specific CTLs/mL blood.