Fig 5.

SAP gene correction of CTLs from patients with XLP1 restores cytotoxicity in vitro. A,In vitro cytotoxic activity of CTLs generated from both healthy donors and EBV-seropositive patients with XLP1 (gene corrected and uncorrected) against allogeneic LCL target cells before intravenous infusion into NSG mice, as measured in a ⁵¹Cr release assay. Assays were performed in triplicates, and data shown are means ± SEMs of all values. B, Specificity of SAP function was determined by using non-LCL targets in a cytotoxicity assay in parallel. Murine mastocytoma P815 cells were cocultured with corrected and uncorrected effector cells from healthy donors and patients incubated with soluble anti-CD3. CTLS from all donors, including patients with XLP1, displayed cytotoxic activity, suggesting that EBV⁺ LCL-targeted killing is SAP and not CD3 mediated.