Figure 1. HOIP ligase activity is required for development of CD4⁺ or CD8⁺ T cells.

(a) Thymocytes from T-HOIP^Δlinear mice and HOIP^+/+ mice were stained with anti-CD4, anti-CD8α, anti-CD25, anti-CD44, anti-TCRβ and anti-TCRγ antibodies and their frequencies were evaluated by flow cytometry. The panels of TCRβ/TCRγ and CD4/CD8 were gated on lymphocytes in an FSC/SSC gate. The panel of CD44/CD25 was gated on CD4⁻CD8⁻ cells. The number indicates the percentage of each population in the viable cell fraction. (b) Absolute numbers of total thymocytes, TCRβ⁺ cells, CD4⁺CD8⁺ cells (DP), CD4⁺CD8⁻ (CD4SP) and CD4⁻CD8⁺ (CD8SP) cells from T-HOIP^Δlinear (open) or HOIP^+/+ (filled) mice at 8 weeks of age are shown. Data are shown as means ± SEM. *p < 0.05 (c) Thymocytes from T-HOIP^Δlinear mice or HOIP^+/+ mice were stained with anti-CD4, anti-CD8α, anti-TCRβ, anti-CD24 and anti-CD69 antibodies and the frequencies of cells expressing CD24/TCRβ or CD69 were determined by flow cytometry using gates for CD4⁺CD8⁺ (DP), CD4⁺CD8⁻ (CD4SP) and CD4⁻CD8⁺ (CD8SP) cells. The number indicates the percentage of CD69⁺ cells in the DP, CD4SP and CD8SP cell fractions. The data in these figures are representative of four independent experiments.