Phenotype of SAP-deficient CTLs. Phenotype of CD8⁺ T cells from SAP-deficient patients (SAP; □) and healthy donors (ND; ▪) in a resting state or after activation with 1 μg/mL anti-CD3 mAbs or stimulation with 100 ng/mL IL-15 (mean ± SD of 3 SAP-deficient patients and 3 healthy donors is shown). (A) Mean fluorescence intensity of the intracytoplasmic staining of the lytic molecules perforin and granzyme-B. (B) Percentage of CD8⁺ T cells staining positive for the CD2-superfamily receptors SLAM, 2B4, and CD84. (C) Percentage of CD8⁺ T cells staining positive for the T-cell activation markers CD25, CD69, and CD56. One representative experiment of 3 performed is shown.