Tcms systemically eliminate host anti-donor T cells. Seven-hundred TCR transgenic 2c-Luc⁺ CD8⁺ cells were injected on day −1 into supralethally irradiated (4Gy on day −5 and 10Gy on day −2) C57BL/6 mice. One day after 2c administration, the mice received 3 × 10⁶ Balb/c-nude BM cells (“HTC only”) or BM+5 × 10⁶ (CB6)F1 Tcm (“HTC+Tcm”). (A) Images were taken at indicated days after transplantation in live anesthetized animals using IVIS. Color intensity is normalized for all images. (B) On day 9 after transplantation, organs (LN, spleen, BM, lung, and liver) were harvested from 5 animals from each group and numbers of live (7aad⁻) CD8⁺ 2c cells were assessed by FACS analysis. Total numbers of 2c cells harvested from all organs tested in the absence (black bar) or presence (gray bar) of Tcm treatment are presented. Data represent mean ± SD of total numbers of 2c cells from 5 animals in each group (***P < .001). (C) Survival curves of mice from the different treatment groups.