Inhibition of T-cell development and generation of intrathymic B cells in fetal thymic organ cultures reconstituted with DNMAML1 or Dtx1-transduced fetal liver cells. Day 15.5 fetal liver cells were transduced with the control retrovirus MigR1, Mig DNMAML1, or Mig Dtx1. Irradiated fetal lobes were reconstituted with the transduced fetal progenitors and cultured for 2 weeks before flow cytometric analysis. (A) GFP expression. (B) T-cell differentiation as assessed by anti-CD4 and anti-CD8 staining in the GFP^- (internal control) and GFP⁺ populations. (C) Generation of intrathymic B cells as assessed with antibodies against B220 and sIgM. Results are representative of 3 independent experiments. The numbers in quadrants and above brackets indicate the percentage of cells.