WASP expression and lymphocyte counts following transplantation of WASP^— stem cells transduced with the MWG vector. (A) Western blot analysis was performed on extracts of peripheral blood leukocytes from WT and WASP^— mice (left 2 lanes), 2 mice that received transplants of WT cells cocultured with 3T3 (M = mock) rather than vector producer cells, 2 animals that received transplants of WASP^— cells transduced with the control vector (MG), and 3 animals that received transplants of WASP^— cells transduced with the WASP expression vector (MWG) shown. The same extracts run on a parallel gel were analyzed for actin levels as a control for loading comparability among the lanes. The percentage of GFP⁺ lymphocytes are given for the animals that received transplants of transduced bone marrow cells. The FACS analysis was performed and extracts were prepared 20 weeks after transplantation. (B) Total lymphocyte counts plotted as a function of the percentage of GFP⁺ T lymphocytes for individual mice. Data are pooled from 4 separate experiments. Animals in the experimental cohort and the 2 control cohorts that did not have more than 1% of GFP⁺ cells in at least one lineage were excluded from the analysis. Blood was obtained for flow cytometric analysis and complete blood count at 14 to 24 weeks after transplantation. (C-D) Corresponding data from the control cohorts of mice. Best-fit linear regression curves are shown.