Transgenic TCRαβ overexpression rescues the delay in T-cell leukemia development induced by Rag2 deficiency in TEL-JAK2 transgenic mice. (A) Kaplan-Meier leukemia-free survival curves for Rag2-deficient EμSRα-TEL-JAK2 Marylin TCR double-transgenic female (Fem) and male mice. The survival curves for EμSRα-TEL-JAK2 transgenic mice bred with Rag2-deficient mice (shown in Figure 3A) are depicted for comparison. The number of mice in each group is given in parentheses. Mice deceased from unrelated causes were censored in the analysis (tick marks). (B) Vβ6 TCR expression in representative Rag2-deficient EμSRα-TEL-JAK2 Marylin TCR double-transgenic females (bottom panel). As a control, Vβ6 TCR expression levels in CD4/CD8 double-positive (DP) and CD4 single-positive (CD4SP) thymocytes from Rag2-deficient Marylin transgenic female are shown (top panel). (C) CD4/CD8 costaining in representative Rag2-deficient EμSRα-TEL-JAK2 Marylin TCR double-transgenic females (nos. 1001, 1021, 1029, 1030, and 1033) and a Marylin/Rag2^−/− female. (D) Thymus, spleen, and lymph node weights were determined for Rag2^+/− (n = 9), Rag2^−/− (n = 8), and Marylin/Rag2^−/− (n = 14) TEL-JAK2 transgenic mice. *P < .05; **P < .01 (unpaired t test). Average organ weight is indicated by horizontal bars.