A, mean percentages of host type H-2Kd+CD4+CD25+Foxp3+ cells among CD4+splenocytes before and after combined heart and bone marrow transplantation in TLI/ATS conditioned wild type BALB/c hosts (WTH/T/A/B)(undep), or in the same hosts that were given a single dose of anti-CD25 mAb on day -7 (CD25 dep) or in CD1-/- BALB/c hosts without anti-CD25 mab treatment (undep). Brackets show standard errors. N=4-5 mice for each time point B, mean percentages of CD4+CD25+Foxp3+ cells in wild type BALB/c mice given conditioning components with or without heart transplantation. N=4-5 mice for each time point. C, Mean absolute numbers of CD4+ naïve, Treg, and NKT cells in the spleen of untreated BALB/C mice or those given TLI alone, ATS alone or the combination of TLI and ATS on day 1 after conditioning (N= 5). D, Fold change in mean absolute numbers of treated and untreated mice. E, Mean absolute numbers of non-NKT and NKT cells in the spleen of wild type and p53-/- mice after conditioning with TLI alone (17 doses) compared to untreated mice (N= 6). Mice were C57BL/6, since p53-/- BALB/C were unavailable. F, Fold change in mean absolute numbers of untreated and treated mice in E.