Repopulation of EBV-specific CD8⁺ T lymphocytes following partially T-cell—depleted SCT. Each panel shows the recovery of CD8⁺ T cells directed against a single EBV-specific epitope as measured by tetramer technology. Results of CD8⁺ T cells specific for 3 lytic epitopes are shown in the left panels and those of CD8⁺ T cells specific for 6 latent epitopes in the middle and right panels. The horizontal continuous lines indicate the upper limits of the normal ranges, which were defined as the maximum results obtained in 16 to 24 healthy EBV-seropositive individuals. The horizontal dotted lines indicate the median values of each T-cell subset in the healthy EBV-seropositive individuals. The lower limits of the normal ranges as defined by this criterion were less than 0.5 cells per cubic millimeter for all 9 T-cell subsets. See the legend to Figure 1 for further details.