Interleukin-2 and lymphokine activated killer cells: promises and cautions

The purposes of this work are to: review the biological activities of Interleukin-2 (IL-2); evaluate the reported therapeutic benefits and toxicity of IL-2/lymphokine activated killer (LAK) cells; and project the role of IL-2/LAK cells in cancer therapy. Interleukin-2 is a glycoprotein lymphokine (mw 15,000) produced naturally by mitogen or antigen stimulated T-lymphocytes. The activities of IL-2 include: enhancement of IL-2 receptor positive T-lymphocytes and a variety of other in vitro and in vivo alterations of T cell function. The IL-2 gene has been cloned from the Jurkat leukemia cell line and expressed by recombinant biotechnology in an E. coli vector. In vitro incubation of IL-2 with selected T-lymphocytes results in the formation of lymphocyte activated killer (LAK) cells. Rosenberg and colleagues, in 1983, demonstrated that both exogenous IL-2 and LAK cells were needed in order to get maximum tumor regression in a murine model and later humans. Patients selected for IL-2/LAK cell therapy have clinical metastases or advanced unresectable cancers. Almost all patients treated demonstrate some toxic effects, including chills, fever, nausea, vomiting, diarrhea and hepatic dysfunction. Approximately 75 percent of the patients have profound hypotension and require intensive nursing care. A review of the literature indicates that tumor responsiveness will range from negligible (adenocarcinoma of the lung with metastases) to a 30+ percent response in renal cell carcinoma when complete and partial responders are totalled. Interleukin-2/LAK cell therapy has promise for some wide spread tumors for which no other therapy is available.(ABSTRACT TRUNCATED AT 250 WORDS)