Generation of LAK cell activity. LAK cell activity of human PBMCs was tested against Daudi lymphoma cells after 4 hours incubation with chTNT-3, rhuIL-2, chTNT-3/IL-2 WT, or IL-2 fusion protein analogs. (A) Arg38 analogs; (B) Met39 analogs; and (C) Asp20, Phe42, and His55 analogs.