A, NK-cell cytotoxicity assay in IL-2–stimulated PBMCs from P3 and relatives. B, NK-cell degranulation assay in IL-2–stimulated PBMCs from P3 and relatives. C, CD8+CD57+ T-cell degranulation assay in IL-2–stimulated PBMCs from P3 and relatives. D, NK-cell cytotoxicity assay in IL-2–stimulated PBMCs from P4 and relatives. E, NK-cell degranulation assay in IL-2–stimulated PBMCs from P4 and relatives. F, CD8+CD57+ T-cell degranulation assay in IL-2–stimulated PBMCs from P4 and relatives. G, Western blot analysis of Rab27a in P4 and relatives. H, Western blot analysis of Rab27a in P5.