       Document 0674
 DOCN  M9610674
 TI    Interleukin-12.
 DT    9601
 AU    Germann T; Rude E; Institute for Immunology, Mainz, Germany.
 SO    Int Arch Allergy Immunol. 1995 Oct;108(2):103-12. Unique Identifier :
       AIDSLINE MED/96021091
 AB    Interleukin (IL)-12 was originally identified as a factor produced by
       human Epstein-Barr virus-transformed B cell lines. It was detected by
       one group as cytotoxic lymphocyte maturation factor, a cytokine that
       synergized with IL-2 in the induction of lymphokine-activated killer
       cells and cytotoxic T lymphocytes. A second group characterized it as a
       natural killer (NK) cell stimulatory factor, due to the enhancement of
       cytotoxicity and IFN-gamma synthesis by NK cells. Human IL-12 was
       purified to homogeneity and cloned by both groups. We had identified a
       murine factor, provisionally termed T cell-stimulating factor (TSF),
       which was involved in the proliferation, synthesis of IFN-gamma and cell
       adhesion of CD4+ Th1 cells. TSF was produced in the antigen-specific
       interaction between Th1 cells and macrophages as antigen-presenting
       cells, partially purified from supernatants of such cultures, and shown
       to be identical to IL-12. Monocytes/macrophages appear to be the major
       source of IL-12. It is rapidly produced by phagocytic cells after
       stimulation with several bacteria/bacterial products and other
       microorganisms. In the light of its effects on NK cells as well as CD4+
       and CD8+ T cells, IL-12 can be regarded as a cytokine that connects the
       innate immune system with the acquired immunity. IL-12 has a broad range
       of activities already reviewed in three papers. These include the
       regulation of cytokine synthesis and proliferation of T and NK cells,
       the promotion of Th1 cell development, the differentiation of CD8+ T
       cells and effects on hematopoiesis. When applied in vivo, IL-12 was
       shown to enhance the resistance to bacterial and parasitic infections,
       to promote antitumor immunity, and to influence antiviral responses
       including HIV in vivo or in vitro. This review will briefly summarize
       these effects, but mainly focus on recent results concerning the
       regulation of the production and the activity of IL-12, its role in the
       differentiation of Th cells and the implications for delayed- and
       immediate-type hypersensitivity reactions, its importance for
       organ-specific autoimmune diseases, and the possible role of the
       IL-12p40 homodimer as a specific inhibitor of the IL-12 heterodimer.
 DE    Animal  Antibody Formation  Autoimmune Diseases/PHYSIOPATHOLOGY  Cell
       Differentiation  Communicable Diseases/PHYSIOPATHOLOGY  Hematopoiesis
       Human  Hypersensitivity/PHYSIOPATHOLOGY
       Interleukin-12/CHEMISTRY/*PHYSIOLOGY  Killer Cells, Natural/PHYSIOLOGY
       Receptors, Interleukin/PHYSIOLOGY  Shock, Septic/PHYSIOPATHOLOGY  Signal
       Transduction  T-Lymphocytes/PHYSIOLOGY  JOURNAL ARTICLE  REVIEW  REVIEW,
       ACADEMIC

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

