In vivo analysis of donor splenocyte depletion. (A) Lethally irradiated BALB.B mice underwent transplantation on day 0 with B6 TCD-BM cells and 5 × 10⁶ tetramer-depleted (LYL8 or HSV8) CD3⁺ B6 T cells. On day 6, host mice were killed and their splenocytes were coincubated with FITC-anti-CD8α and PE-LYL8 H2K^b tetramers. Prior to acquisition, 7-AAD was added to each sample to allow gating on live cells. Dot plots gated on live CD8⁺ lymphocytes are shown; the percentage of LYL8 tetramer-positive CD8⁺ cells is shown in the top right quadrant and is an average of 3 mice per condition. (B) Lethally irradiated BALB.B mice underwent transplantation on day 0 with B6 TCD-BM cells and 12 × 10⁶ CFSE-labeled, tetramer-depleted (LYL8 or HSV8) CD3⁺ B6 T cells. On day 3, host mice were killed and their splenocytes were incubated with PECy7-anti-CD8α. Shown are dot plots gated on CD8⁺ lymphocytes; the percentage of cells within each population is shown above each region and represents an average of 4 samples per condition (2 independent samples from 2 mice per condition).