Lymphokine activated killer cells were generated from peripheral blood lymphocytes (PBL) in patients with cervical carcinoma. The cytotoxic potential of these cells was determined against three tumor cell lines (K-562, RAJI and MCF-7) using a short-term 51Cr-release assay. Both normals and patients showed comparable levels of LAK activity. Phenotypic analysis of cells having LAK activity showed a heterogeneous population. A significant increase in the expression of CD25 marker (IL-2R, Tac) of PBL population was observed after IL-2 culture. In addition, the indigenous ability of peripheral blood mononuclear cells to produce IL-2 in response to mitogen PHA was almost the same as observed in case of normal individuals.