       Document 0899
 DOCN  M9620899
 TI    HIV-1 gp120/160 expressing cells upregulate HIV-1 LTR directed gene
       expression in a cell line transfected with HIV-1 LTR-reporter gene
       constructs.
 DT    9602
 AU    Merzouki A; Patel P; Cassol S; Ennaji M; Tailor P; Turcotte FR;
       O'Shaughnessy M; Arella M; Virology Research Center Institut
       Armand-Frappier, Laval, Quebec,; Canada.
 SO    Cell Mol Biol (Noisy-le-grand). 1995 May;41(3):445-52. Unique Identifier
       : AIDSLINE MED/96059407
 AB    The results described in this paper demonstrate that HIV-1 gp120 can
       upregulate gene expression directed by the HIV-1 LTR. Briefly, exposing
       responder CD4+CEM-T4 ID5 cells to stimulator CEMgp120/160 expressing
       cells (stably transfected with HIV-1 LTR-CAT and HIV-1 gp160,
       respectively) resulted in the increased synthesis of the CAT enzyme.
       Control non-transfected CEM-T4 cells did not induce the synthesis of
       CAT. In addition, when the responder cell line, U937-1C5 which also
       contains stably transfected HIV-1 LTR-CAT plasmid was exposed to
       irradiated CEM gp120/160 cells, there was no synthesis of the CAT
       enzyme. Neither recombinant gp120 nor gp160 were able to stimulate the
       synthesis of CAT in the responder cells. These results indicate that the
       mechanism by which gp120/160 expressed on transfected cells increase CAT
       synthesis in responder cells may be dependent on the manner which the
       protein is presented in association with accessory molecules. Moreover,
       recombinant soluble CD4 and anti-CD4 monoclonal antibodies inhibited CEM
       gp120/160 induced expression of HIV-1 LTR-directed expression in CEM-1D5
       cells. Based on these results we hypothesize that HIV or its envelope
       protein, gp120, upon interaction with its receptor, the CD4 molecule on
       T helper cells, transduces a signal which translates into the
       upregulation of the gene expression directed by the HIV-1 LTR.
 DE    Antibodies, Monoclonal/PHARMACOLOGY  Antigens, CD4/IMMUNOLOGY  Cell
       Line/RADIATION EFFECTS  Flow Cytometry  *Gene Expression Regulation,
       Viral  Gene Products, env/BIOSYNTHESIS/GENETICS/*METABOLISM  *Genes,
       Reporter  Human  HIV-1/*GENETICS  Kinetics  Protein
       Precursors/BIOSYNTHESIS/GENETICS/*METABOLISM  Repetitive Sequences,
       Nucleic Acid/*GENETICS  Signal Transduction  Support, Non-U.S. Gov't
       Tetradecanoylphorbol Acetate/PHARMACOLOGY  Transfection  JOURNAL ARTICLE

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

