mESC-derived TEP-treated allo-BM transplant recipients do not develop GVHD but exhibit host and mESC tolerance. (A-E) Lethally irradiated C57BL/6 mice were injected intrathymically with mESC-derived EpCAM1⁺ cells and intravenously with TCD BM from BALB/c mice. Syngeneic BMT (both BM and recipients from 129SVEVTac mice) was used as controls. (A) Survival was monitored daily; (B) weights and (C) clinically GVHD scores were evaluated weekly; (D) histopathologic analysis of signs of GVHD in liver, small bowel (SB), and large bowel (LB) were performed on day 90 after BMT. (E) Lethally irradiated BALB/c were injected intrathymically with TC-1 mESC-derived EpCAM1⁺ cells and intravenously with TCD BM from CBA mice. (F) Lethally irradiated BALB/c were injected intrathymically with TC-1 mESC-derived EpCAM1⁺ cells and intravenously with TCD BM from BALB/c mice. (E-F) Ninety days later, splenocytes were harvested and used as effector cells for MLRs. Splenocytes from normal non-BMT CBA or BALB/c mice are used as controls. The effector cells were mixed with irradiated splenocytes (as stimulators) from BALB/c, 129SVETac, and CBA mice, respectively. Cell proliferation was determined by [³H]-thymidine incorporation. Data are shown as stimulation index. (E) Mean CPM in MLRs with splenocytes from BMT recipients or normal CBA mice as effectors and splenocytes from BALB/c, 129SVETac, and CBA mice as stimulators were 978, 979, 987, and 46 012, 29 861, and 1053, respectively. (F) Mean CPM in MLRs with splenocytes from BMT recipients or normal CBA mice as effectors and splenocytes from BALB/c, 129SVETac, and CBA mice as stimulators were 917, 945, 4775, and 971, 24 765, and 41 729, respectively. The data are representative of 3 independent experiments.