Cultured T cells (CTC) were expanded in Interleukin-2 (IL-2) and used as reagents in cell mediated lympholysis (CML). CTC were able to induce the generation of primary cytotoxic effector cells and to function as 51Cr labeled target cells and cold target inhibitors. Since large numbers of CTC can be produced from as few as 1-2 X 10(6) lymphocytes within a short period of time, these reagents will enable CML studies to be performed in a broader range of situations, including those with were heretofore impossible.