       Document 0419
 DOCN  M9590419
 TI    Comparison of the response to T-cell activation by integrated HIV-1 and
       HTLV-1 LTR-lacZ vectors.
 DT    9509
 AU    Copeland KF; Hendrikx PJ; Haaksma AG; Fiering S; Van Lier R; Goudsmit J;
       Heeney JL; Laboratory of Viral Pathogenesis, Biomedical Primate
       Research; Centre, Rijswijk, The Netherlands.
 SO    Virology. 1995 Jun 1;209(2):633-6. Unique Identifier : AIDSLINE
       MED/95297164
 AB    Human Jurkat T-cell clones containing stably integrated HIV-1 LTR or
       HTLV-1 LTR/lacZ vectors were studied to compare the responses of
       integrated LTRs to T-cell activation. Responses were compared also with
       those obtained in parallel with Jurkat cells stably expressing lacZ
       under the control of the cellular enhancer element NF-AT of the IL-2
       promoter. Activation induced via the cell surface TCR/CD3 complex or the
       CD28 receptor elicited responses from the LTR of HIV-1; however, HTLV-1
       LTR-directed expression was not observed following triggering of these
       cell surface pathways. Mitogenic activation by elevation of
       intracellular calcium (Ca2+) levels along with protein kinase C (PKC)
       signals was required for optimal expression of the HIV-1 LTR and the
       NF-AT element; however, increased intracellular Ca2+ was inhibitory to
       PKC-mediated expression from the HTLV-1 LTR. Time course experiments
       revealed a sustained PKC-mediated response by the HTLV-1 LTR, which was
       detectable in the absence of Ca2+ as early as 6 hr following
       stimulation. In contrast to the HTLV-1 LTR, in time course experiments
       the HIV-1 LTR responded to stimulation by mitogenic activation of PKC in
       the absence and presence of Ca2+ and by antiCD3 with lacZ expression
       beginning as early as 3 hr poststimulation. These results suggest that
       the HTLV-1 LTR appears to be refractory to several cellular pathways
       which are upregulatory to the HIV-1 LTR.
 DE    beta-Galactosidase/BIOSYNTHESIS  Cell Line  Comparative Study  Genetic
       Vectors  Human  *HIV Long Terminal Repeat  HIV-1/GENETICS/*IMMUNOLOGY
       Kinetics  *Lymphocyte Transformation  Recombinant Proteins/BIOSYNTHESIS
       Support, Non-U.S. Gov't  T-Lymphocytes/*IMMUNOLOGY/*VIROLOGY
       Transfection  Tumor Cells, Cultured  Virus Integration  JOURNAL ARTICLE

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

