FIGURE 4. MCL-1 is required for mature lymphocyte survival.

a, Viability of T cells cultured with or without cytokines (10 ng ml^-1) for 24 h. Mean s.e.m. percentage viability of triplicate experiments as determined by Annexin-V. b, MCL-1 protein levels in T cells after 24 h culture (10 ng ml^-1 cytokines) as determined by immunoblot. c, Mean s.e.m. of triplicate assays for Mcl-1 mRNA levels normalized to HPRT for cultured purified T lymphocytes after 30, 120 and 360 min of exposure to cytokines (10 ng ml^-1). d, Mean s.e.m. percentage viability of triplicate experiments for purified splenic T cells from MxCreMcl-1^f/wt or MxCreMcl-1^f/null after 48 h of culture with or without IFN- to induce deletion and/or IL-7. e, Number of total splenic cells (mean s.e.m.) from three mice of each genotype at 6 weeks of age, assessed 7 days after pI-pC treatment. f, Mcl-1^f/null or MxCreMcl-1^f/null purified T or B lymphocytes were adoptively transferred to Rag-2-deficient recipients. After engraftment, pI-pC was delivered to delete the Mcl-1^flox allele. Mice were analysed at day 0 (before pI-pC), day 2 and day 7 to determine CD3⁺ and B220⁺ lymphocytes in the spleen and lymph nodes. The mean s.e.m. represents the percentage of initial B or T cells recovered in recipient mice at day 0, for three recipient mice at each time point.