Patterns of EBV-specific cytotoxicity and cytokine secretion by 27 EBV-specific CD8⁺ T-cell clones from donor MJC. (A) Correlation of cytotoxicity and IL-4 secretion (r = −.59, P < .001). (B) Correlation of cytotoxicity and IL-10 secretion (r = −.63, P < .0008). (C) Correlation of cytotoxicity and IFNγ secretion (r= −.79, P < .0001). Cytotoxicity was measured in a 5-hour⁵¹Cr-release assay at an effector:target ratio of 4:1. Cytokine secretion was measured by ELISA of 48-hour supernatants from anti-CD3–activated T-cell cultures, as described in Materials and Methods.