Transplantation of MBECs is associated with improved survival in mice following 1050 cGy total body irradiation. (A) Control C57Bl6 mice were irradiated with 1050 cGy total body irradiation, and their survival was compared with mice that were irradiated with 1050 cGy and then given transplants of MBECs for 5 days, as described in “Materials and methods.” Whereas 100% of control, irradiated mice (n = 11) died prior to day +30 (gray line), 57% of mice that received a transplant of MBECs (n = 7) survived through day +60 without evidence of morbidity (black line, P = .04). (B) The survival of control C57Bl6 mice that were irradiated with 1050 cGy (n = 9, gray line) was compared with the survival of C57Bl6 mice that were irradiated with 1050 cGy and given transplants of FBECs (n = 9, solid black line) or MSCs (n = 7, dashed black line). FBEC transplantation was associated with a significant increase in percent survival compared with controls or mice that received a transplant of MSCs (P = .002 and P = .002, respectively), although these mice failed to survive in the long term.