J Leukoc Biol. 1994 Feb;55(2):280-8. doi: 10.1002/jlb.55.2.280.


Interleukin-12 (IL-12) is a newly characterized cytokine that has a unique heterodimeric structure. It was initially cloned from B lymphoblastoid cell lines, but the majority of IL-12 is produced by macrophages/monocytes following appropriate stimulation. IL-12 can (1) enhance the cytolytic activity of a number of effector cells including T cells, natural killer (NK) cells, lymphokine activated killer (LAK) cells, and macrophages, (2) increase proliferation of activated NK and T cells, (3) induce production of cytokines, such as interferon gamma, (4) stimulate the induction of TH1 cells, (5) upregulate a number of cell surface molecules, (6) inhibit IgE secretion, and (7) act as a synergistic factor for hematopoietic stem cells. Based on these potent immunomodulatory activities, IL-12 has been evaluated in several disease models for parasitic infections and malignancies. Marked activity of IL-12 against both Leishmania and Toxoplasma has been reported. Likewise, antimetastatic and antitumor activity, including tumor regression, has been observed against a number of murine malignancies treated with IL-12 using doses that result in little toxicity. The results suggest that IL-12 may be a useful cytokine for the treatment of a number of diseases.

Publication types

  • Review

MeSH terms

  • Animals
  • B-Lymphocytes / immunology*
  • B-Lymphocytes / metabolism
  • Cell Division / drug effects
  • Cytokines / biosynthesis
  • Cytotoxicity, Immunologic / drug effects
  • Disease Models, Animal
  • Humans
  • Interleukin-12
  • Interleukins / pharmacology
  • Interleukins / physiology*
  • Interleukins / therapeutic use
  • Leishmaniasis / therapy
  • Lymphocyte Activation / drug effects
  • Lymphocytic Choriomeningitis / therapy
  • Mice
  • Neoplasms, Experimental / therapy
  • T-Lymphocytes / immunology*
  • Toxoplasmosis, Animal / therapy


  • Cytokines
  • Interleukins
  • Interleukin-12