Thymic development in Gimap5^−/− mice. Representative FACS plots of wild-type (wt) or Gimap5-deficient (^−/−) thymocytes. (A) Expression of CD4 and CD8 in unfractionated thymocytes. Boxes indicate gates used to calculate the average frequencies included in the text. (B) Expression of CD44 and CD25 in DN thymocytes contained in the DN gate of panel A. (C) Expression of CD69 and H57/TCR-β (TCR) in DP thymocytes contained in the DP gate of panel A. (D) Expression of CD69 and Qa2 in CD4SP and CD8SP thymocytes. The relative accumulation of CD69^LOWQa2⁻ versus CD69^LOWQa2⁺ cells indicates a defect in the final stages of intrathymic T-cell maturation in Gimap5^−/− mice.