Absence of erythroid and myeloid repopulation by Sp3^-/- fetal liver cells in an in vivo transplantation assay. (A) Analysis for CD3 expression and lacZ activity in total thymocytes from Sp3^+/- and Sp3^-/- transplant recipients. (B-E) Total cell suspensions from spleen (panel B), bone marrow (panel C), peripheral blood (panel D), and peritoneal cavity (panel E) were analyzed for lymphoid-, erythroid-, or myeloid-specific marker expression (left). In Sp3^+/- and Sp3^-/- transplant recipients, the indicated subpopulations were gated and analyzed for donor-derived lacZ expression (right). The results for transplanted Sp3^-/- cells are from the animal in which the highest percentages of lacZ⁺ cells were observed. LacZ expression data are displayed as histograms; the numbers are the proportions of lacZ⁺ cells in which background values in wild-type mice were lower than 4%.