Secondary transplantation of STAT5-deficient BM cells with and without competition with wild-type BM cells.

Chimeric mice were first generated by primary transplant of either wild-type or STAT5-deficient BM cells into irradiated HW80 recipients. (A) For the competitive secondary transplant experiment, BM was collected 16 weeks following transplantation and mixed at a 1:1 ratio with Ly-5.1 BM from identically derived primary recipients. Sixteen weeks following secondary transplant, mice were analyzed for peripheral blood percentage of Ly-5.2–positive cells. (B) For the noncompetitive secondary transplant experiments, BM cells were injected into irradiated recipients, and secondary engraftment was documented following transplantation into either HW80 recipients using hemoglobin electrophoresis (top panels) or following transplantation into Ly-5.1 recipients using FACS for total Ly-5.2 (panels labeled Ly-5.1, Ly-5.2, +/+ 2⁰ BMT, −/− 2⁰ BMT) or multilineage reconstitution (panels labeled B220, Gr-1, CD4, Ter119 under the columns for wild-type and STAT5ab^−/−).