Interleukin-12,a New Anti-Tumor Cytokine

Abstract

Of the numerous cytokines that have been isolated and characterized over the last several years, few have attracted as much attention as Interleukin-12 (IL-12). Since its discovery ten years ago, the intracellular signaling pathways activated by IL-12 have been identified, the individual components of the receptor cloned, and many of its effects on cellular immune function documented. Recombinant murine IL-12 has been subjected to extensive investigation in animal models of cancer and parasitic infection and shown great promise as an antitumor agent and a potential treatment for leishmaniasis. Preclinical data suggest that it may also be useful in the treatment of antibiotic-resistant tuberculosis and AIDS. Recombinant human IL-12 (rhIL-12) has recently entered Phase I and II clinical testing in cancer patients. The following is a brief review of the immunologic effects of IL-12, the results of animal studies, and data from recently completed clinical trials.