Cytotoxicity of ex vivo–expanded cells.

Cells derived from C57BL/6 (H-2^b) were assessed at the initiation of culture and at different time points against the target cell P3 × 63 (H-2^d). (B) Cytotoxicity of ex vivo–expanded CD8⁺ NKT cells against syngeneic and allogeneic targets. C57BL/6 (H-2^b)-expanded CD8⁺ NKT cells at day 21 of culture were assayed for cytotoxicity against a panel of syngeneic and allogeneic target cells. Cytotoxicity was assessed after 4 hours at different target-to-effector ratios, ranging from 1:5 to 1:40. Results are representative of more than 3 experiments. ■ indicates 1:5; ▧, 1:10; ⊠, 1:20, and ▪, 1:40.