       Document 0716
 DOCN  M9650716
 TI    Inhibition of HIV type 1 Tat-mediated trans-activation by oncostatin M
       in HLtat cells.
 DT    9605
 AU    Este JA; Witvrouw M; Tu J; Desmyter J; De Clercq E; Vandamme AM; Rega
       Institute for Medical Research, Katholieke Universiteit; Leuven,
       Belgium.
 SO    AIDS Res Hum Retroviruses. 1995 Nov;11(11):1355-8. Unique Identifier :
       AIDSLINE MED/96159132
 AB    We have tested the effect of oncostatin M (OSM) on the Tat-mediated
       trans-activation in a HeLa cell line (HLtat) expressing Tat, using a
       transfection assay with the LacZ gene under the control of the HIV-1
       LTR. Oncostatin M reduced the LacZ expression by 50% at a concentration
       of 9.5 ng/ml (IC50), which was far below the 50% cytotoxic concentration
       (CC50 > 400 ng/ml). Although HLtat cells may represent an interesting
       model for the study of the signal transduction pathway of OSM, this
       cytokine did not inhibit the tumor necrosis factor (TNF)-dependent
       activation of the HIV LTR in Molt pNAZ cells or the Tat-mediated
       trans-activation in HeLa, HeLa-CD4, Hep-II, COS-7, or Jurkat-tat cells.
       Likewise, OSM did not show any anti-HIV-1 activity in the MT4 cell/MTT
       assay. Our findings with OSM indicate that, for the screening of HIV Tat
       inhibitors, care must be taken in selecting a system that not only
       emulates HIV Tat trans-activation, but is also representative for in
       vivo-infected cells.
 DE    Antiviral Agents/*PHARMACOLOGY  Cell Line  Gene Expression/DRUG EFFECTS
       Gene Products, tat/ANTAGONISTS & INHIB/*GENETICS  Hela Cells  Human
       HIV-1/*DRUG EFFECTS/METABOLISM  Peptides/*PHARMACOLOGY  Support,
       Non-U.S. Gov't  Trans-Activation (Genetics)/*DRUG EFFECTS  JOURNAL
       ARTICLE

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

