The precursor cells of mouse lymphokine-activated killer (LAK) cells

Culture of mouse spleen cells with recombinant human interleukin 2 (r-IL 2) resulted in the generation of lymphokine-activated killer (LAK) cells, which could lyse a variety of tumor cells. Negative selection study using various kinds of antibodies and complement indicated that LAK precursor cells existed in both mature spleen lymphocytes and immature spleen null cells. LAK cells were also induced from lymph node cells but not from unfractionated thymocytes. However, hydrocortison (HC)-resistant thymocytes or PNA- thymocyte subpopulations were highly responsive to r-IL 2 and maturated into LAK cells after 5 day-culture with r-IL 2. Moreover, it was demonstrated that r-IL 2 allowed the induction of LAK cells from nude mouse spleen cells, but not from bone marrow cells and fetal liver cells.