Fig. 1.

Deletion of Cdc42 causes a defect in T-cell homeostasis. (A) Generation of Cdc42^−/− T cells. The loxP/Cre-mediated gene-targeting strategy was used to generate the Cdc42 gene-deleted allele (Cdc42⁻) in T cells. Expression of Cdc42 in thymocytes was analyzed by anti-Cdc42 Western blotting. The level of β-actin was blotted in parallel as a loading control. (B) Cdc42 deficiency causes a loss of mature T cells. Single-cell suspensions from thymus, lymph nodes, and spleen were immunostained with anti-CD4, anti-CD8, and/or anti-TCRβ antibodies. Numbers of T cells are shown. (C) Cdc42 deficiency leads to a loss of naive T cells. The splenocytes were stained for naive and effector (eff) or effector memory (eff mem) T cells with a combination of anti-CD4, anti-CD8, anti-CD44, and anti-CD62L antibodies. The numbers of naive and effector or effector memory T cells are shown. Data are shown as means ± SD; n = 5. In B and C, **P < 0.01; *P < 0.05.