Therapy of cancer using the adoptive transfer of activated killer cells and interleukin-2

A new approach to cancer treatment has been developed based on the adoptive transfer of activated lymphocytes into cancer patients. Lymphocytes harvested from patients by leukapheresis are converted into lymphokine-activated killer (LAK) cells by incubation with recombinant interleukin-2 (rIL-2). These LAK cells are then infused back into the patients in combination with intravenous IL-2. Among 25 patients treated with this form of adoptive immunotherapy there were 11 patients with measurable tumor reductions, including 1 complete responder. The majority of responses occurred in patients with metastatic renal cell carcinoma, melanoma and colorectal carcinoma. The toxicities of IL-2, including fluid retention and pulmonary edema, limit therapy, and laboratory investigation is now aimed toward understanding the mechanism of IL-2 toxicity. The use of LAK cells and IL-2 in cancer therapy is still in a developmental stage and needs to be refined before its role can be definitely established.