Figure 1.

Ebf1-Deficient B-Cell-Lineage-Biased Precursors Possess Increased T Lymphoid Potential

(A) BM cells from chimeras reconstituted with B6 or B6.Ebf1^−/− fetal liver 12 weeks previously were stained with antibodies to the host-specific determinant CD45^SJL and the antibodies shown in Figure S1. 2 × 10⁶ events were collected on an LSR2 flow cytometer and gated as in Figure S1.

(B) 200 WT or Ebf1^−/− B220⁺Ly6D⁻ or B220⁻Ly6D⁺ cells derived from the indicated chimeras were sorted onto pre-established OP9-DL4 cells supplemented with IL-7, FL, and SCF. Seven days later, cells were counted and analyzed for cell surface marker expression. The mean number of viable (DAPI⁻) CD45⁺ early T cell lineage (Thy1.2⁺CD25⁺) cells in triplicate cultures is shown. Error bars indicate SEMs, ^*p < 0.005. Data are representative of three separate experiments.

(C) 96 single WT or Ebf1^−/− B220⁺Ly6D⁻ or B220⁺Ly6D⁺ cells were sorted onto pre-established OP9-DL4 cells in flat-bottom 96-well plates with IL-7, FL, and SCF. Wells containing cell growth were counted and analyzed on day 10. Data are representative of two separate experiments. See also Figure S1.