Loss of NF-κB1 promotes memory marker acquisition independently of MHC class Ia. (A) CD4 and CD8 profiles for wt, nfκb1−/−, Kb−/−Db−/− and nfκb1−/−Kb−/−Db−/− thymocytes. Numbers indicate the percent of thymocytes in each quadrant. (B) CD8 and CD24 expression by thymocytes from each genotype. Numbers represent percentages of CD8+CD24lo cells in each gate. (C) CD44, CD122 and Ly6C expression by CD8+CD24lo thymocytes. Percentages are shown for each gate. (D) Absolute numbers (mean±s.e.m.) of total thymocytes, DP, CD8SP and CD8+CD24lo thymocytes for each genotype; Lower graph shows percentages of CD8SP and CD8+CD24lo thymocytes (mean±s.e.m.). Data in (A–D) are representative of four experiments (4–6 mice per genotype). P-values were determined by an unpaired two-tailed Student's t-test.