Thymocyte differentiation in ZAP-70^−/− mice undergoing transplantation with ZAP-70 genecorrected BM cells.

Thymocytes were harvested from euthanized animals at 18 weeks after BMT and analyzed by flow cytometry. (A) Thymocytes were stained with PE-conjugated αCD8 and Cy-conjugated αCD4 mAbs. The percentages of CD4⁺ and CD8⁺ SP thymocytes are indicated in each dot plot. (B) As a measure of thymocyte differentiation, expression of CD5 and TCRβ was assessed in the EGFP⁻ and EGP⁺ thymocyte populations of ZAP-70^−/− mice undergoing transplantation with control EGFP or ZAP-70/EGFP retroviral vectors. Expression of these 2 markers was also monitored in the total thymocyte population of WT mice and ZAP-70^−/− mice undergoing transplantation with WT BM. The percentages of CD5^hi and TCRβ^hi cells are indicated. Histograms are representative of data obtained from 3 to 4 mice in each group.