D WT and SKAP55−/− OT-I CD8+ CTLs (3 × 106) were injected into C57BL/6 mice, followed by injection of non-pulsed (CFSEhi) or 10 nM OVA257-264-pulsed (CFSElo) splenocytes (5 × 106) to measure in vivo cytotoxicity (mean ± SD, n = 3 mice per group). Representative data of three independent experiments. 