Proliferation and cytokine production of SAP-deficient CD8⁺ T cells. (A) Proliferation of CD8⁺ T-cell lines from healthy donors (mean ± SD of ND1, ND2, and ND3; ▪) and SAP-deficient patients (mean ± SD of SAP1, SAP2, and SAP3; □) after stimulation with the indicated doses of immobilized anti-CD3 mAbs. Proliferation is expressed as cpm values corresponding to ³H-thymidine uptake after a 72-hour stimulation. (B) Intracytoplasmic staining for cytokine production in T cells of healthy donors and SAP-deficient patients 6 hours after stimulation with immobilized anti-CD3 mAbs plus anti-CD28 mAbs or TPA/ionomycin. Numbers in dot plot quadrants refer to percentages of T cells positive for the indicated cytokines. One representative experiment of 3 performed is shown.