Depletion of CD117^hi, CD127⁺, or CD90⁺ precursors does not abrogate T-cell differentiation. Lin⁻ BM cells from B6 CD45.1 mice (test) were depleted of CD117^hi cells, CD127⁺ cells, CD90⁺ cells, or all of them combined (triple), mixed with lin⁻ BM cells from B6 CD45.2 mice (competitor), and transferred intravenously into Il7ra-deficient hosts. Ctl indicates mixture of nondepleted B6 CD45.1 lin⁻ BM cells with B6 CD45.2 lin⁻ BM cells. Donor-derived thymocytopoiesis was analyzed by flow cytometry 2 and 4 weeks after transfer. (A) Representative FACS plots of test versus competitor ratios 2 weeks (top panels) and 4 weeks (bottom panels) after transfer. Numbers in quadrants indicate the percentage of cells. (B) Thymic reconstitution 2 weeks after transfer. Combined analysis of 5 independent experiments with 2 mice per group. Proportions of test populations were normalized to ctl. Data are shown as mean ± SEM; ***P < .001 (C) Thymic reconstitution 4 weeks after transfer. Combined analysis of 5 independent experiments with 2 mice per group. Proportions of test populations were normalized to ctl. Data are shown as mean ± SEM; *P < .02; **P < .01.