Split chimerism after transplantation of C57BL/6 Sca-1⁺Lin⁻ cells (H2^b) into sublethally irradiated (7 Gy) C3H/HeJ recipients (H2^k). Percentages of donor and host T cells (determined by gating of CD3 stained cells) and non-T cells are shown in the appropriate FACS dot plots. Peripheral blood chimerism was determined 30 days posttransplant by cytofluorimetry (see Materials and Methods).