       Document 0647
 DOCN  M9620647
 TI    Ligation of either CD2 or CD28 rescues CD4+ T cells from
       HIV-gp120-induced apoptosis.
 DT    9602
 AU    Tuosto L; Piazza C; Moretti S; Modesti A; Greenlaw R; Lechler R;
       Lombardi G; Piccolella E; Department of Cellular and Developmental
       Biology, University La; Sapienza, Rome, Italy.
 SO    Eur J Immunol. 1995 Oct;25(10):2917-22. Unique Identifier : AIDSLINE
       MED/96062045
 AB    Temporal or quantitative imbalance in signals delivered to T cells via T
       cell antigen receptor (TCR), the CD4 co-receptor, and accessory
       molecules can lead to anergy, apoptosis, or both. This has been observed
       following ligation of CD4 by HIV gp120 prior to TCR occupancy. The
       ability of molecules such as CD2 and CD28, interacting with their
       ligands LFA-3 and B7, to provide signals that protect T cells from the
       induction of anergy, has been reported. Here, we demonstrate that
       ligation of CD2 and CD28 in conjunction with TCR occupancy rescue T
       cells that have been programmed for apoptotic death by prior CD4
       ligation to gp120. This appears to be the result of augmented
       interleukin-2 and interleukin-4 release by the T cells following these
       molecular interactions. In conclusion, our results suggest that an
       impairment of antigen-presenting accessory cell functions could favor
       gp120-mediated apoptosis in HIV-uninfected cells.
 DE    Animal  *Antigen Presentation  Antigens, CD2/*METABOLISM  Antigens,
       CD28/*METABOLISM  Antigens, CD58/IMMUNOLOGY  Antigens,
       CD80/GENETICS/IMMUNOLOGY  Apoptosis/*DRUG EFFECTS
       B-Lymphocytes/IMMUNOLOGY  CD4-Positive T-Lymphocytes/CYTOLOGY/*DRUG
       EFFECTS/METABOLISM  Hemagglutinins, Viral/IMMUNOLOGY  Human  HIV
       Envelope Protein gp120/*PHARMACOLOGY  HIV-1/*PHYSIOLOGY  HLA-DR1
       Antigen/GENETICS/IMMUNOLOGY  Interleukin-2/PHARMACOLOGY/SECRETION
       Interleukin-4/PHARMACOLOGY/SECRETION  L Cells  Leukocytes,
       Mononuclear/IMMUNOLOGY/METABOLISM  Ligands  *Lymphocyte Transformation
       Mice  Monocytes/IMMUNOLOGY  Peptide Fragments/IMMUNOLOGY  Recombinant
       Proteins/PHARMACOLOGY  Support, Non-U.S. Gov't  JOURNAL ARTICLE

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

