Normal numbers of putative thymic CD8αα TCRαβ IEL precursors in c-myc^ΔCD4 mice. A representative CD4 versus CD8α thymocyte profile (identical in WT and c-myc^ΔCD4 mice) is shown to indicate the gates used for panels A and B. (A) Analysis of putative thymic preselection IEL precursors in WT and c-myc^ΔCD4 mice. Total thymocytes were stained with CD4, CD8α, CD8β, and TL-tetramer. CD4⁺ CD8α⁺ thymocytes were analyzed for coexpression of TL-tetramer and CD8β. Numbers in the dot plots indicate percentages. A control experiment for the TL-tetramer staining was performed by incubating thymocytes first with anti-CD8α and subsequently with TL-tetramer. Bar graph represents absolute numbers (mean ± SD; n = 6) of CD4⁺ CD8αβ⁺ TL-tetramer⁺ (TP) thymocytes. (B) Analysis of putative thymic postselection IEL precursors in WT and c-myc^ΔCD4 mice. Total thymocytes were stained with CD4, CD8α, B220, NK1.1, and TCRαβ. DN B220⁻ thymocytes were analyzed for NK1.1 and TCRαβ expression. Numbers in the quadrants indicate percentages. Bar graph represents absolute numbers (mean ± SD; n = 6) of DN NK1.1⁻ B220⁻ TCRαβ⁺ thymocytes.