       Document 0603
 DOCN  M9620603
 TI    Establishment of T-helper type 1- and T-helper type 2-like human
       Toxoplasma antigen-specific T-cell clones.
 DT    9602
 AU    Daubener W; Mackenzie C; Hadding U; Institut fur Medizinische
       Mikrobiologie und Virologie,; Heinrich-Heine-Universitat, Dusseldorf,
       Germany.
 SO    Immunology. 1995 Sep;86(1):79-84. Unique Identifier : AIDSLINE
       MED/96091075
 AB    As an in vitro model for human cerebral toxoplasmosis, we analysed the
       interaction between glioblastoma cells, Toxoplasma and Toxoplasma
       antigen-specific T-helper cells. We established 46 different human CD4+
       T-cell clones from four different donors. All T-cell clones responded to
       Toxoplasma antigen derived from three different Toxoplasma strains. We
       found that the supernatants of 44 clones induced toxoplasmostasis in
       glioblastoma cells. The anti-parasitic effector mechanism activated in
       glioblastoma cells by T-cell supernatants was the induction of the
       tryptophan-degrading enzyme indolamine 2,3-dioxygenase. Enzyme
       induction, as well as the anti-parasitic effect, was blocked by a
       monoclonal antibody directed against interferon-gamma (IFN-gamma), and
       the addition of L-tryptophan to the cultures completely blocked the
       anti-parasitic effect induced by T-cell supernatants. The supernatants
       from two of the 46 established T-cell clones (3A22 and 1A15) were unable
       to induce indolamine 2,3-dioxygenase activity or, as expected,
       toxoplasmostasis in glioblastoma cells. We further analysed the
       supernatants from these two clones, and found that they contained large
       amounts of IL-4 and no, or only limited amounts of, IFN-gamma. We
       therefore conclude that Toxoplasma-antigen is able to activate T-helper
       type 1 (Th1)- and Th2-like human T cells, and only IFN-gamma-producing
       cells are capable of inducing anti-parasitic effector mechanisms.
 DE    Animal  Antigens, Protozoan/*IMMUNOLOGY  Cell Division  Cell Line  Clone
       Cells  Epitopes  Glioblastoma/ENZYMOLOGY/IMMUNOLOGY  Human  Interferon
       Type II/IMMUNOLOGY/PHARMACOLOGY  Interleukin-4/METABOLISM  *Models,
       Immunological  Support, Non-U.S. Gov't  Th1 Cells/CYTOLOGY/*IMMUNOLOGY
       Th2 Cells/CYTOLOGY/*IMMUNOLOGY  Toxoplasma/*IMMUNOLOGY  Toxoplasmosis,
       Cerebral/*IMMUNOLOGY  Tryptophan Oxygenase/METABOLISM  JOURNAL ARTICLE

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

