       Document 0511
 DOCN  M9630511
 TI    Down-regulation of T-cell proliferation in response to soluble anti-CD3
       antibodies through development of redirected cytolytic activity
       eliminating costimulatory cells.
 DT    9603
 AU    Lwin T; Nakashima I; Nagase F; Department of Immunology, Nagoya
       University School of Medicine,; Aichi, Japan.
 SO    Microbiol Immunol. 1995;39(8):599-606. Unique Identifier : AIDSLINE
       MED/96064269
 AB    CD4+ T-depleted spleen cells (CD8+ T cells) activated by anti-CD3
       antibodies (aCD3) suppressed proliferation of CD8+ T-depleted spleen
       cells (CD4+ T cells) and fresh normal T cells in response to aCD3.
       Antigen-nonspecific cytolytic activity was induced in splenic CD8+ T
       cells by stimulation with aCD3 and showed the peak level on day 3,
       whereas cytolytic activity induced in CD4+ T cells was weak. Intact Ig
       but not F(ab')2 of aCD3 induced and mediated cytolytic activity.
       Correspondingly the cytolytic activity induced by aCD3 was directed
       against target cells bearing Ig-binding Fc-receptor activity and
       cytolysis was inhibited by the addition of free Ig into the assay
       system. We showed that aCD3-activated T cells carried a high level of
       aCD3 on their surface at the time after the peak proliferation when they
       attained high cytolytic activity. This raised the possibility that the
       anti-CD3-induced aCD3-redirected cytolytic activity eliminated
       Fc-receptor-bearing costimulatory cells in the culture for
       down-regulation of the T-cell proliferation. This view was supported by
       partial restoration of anti-CD3-induced low responsiveness of CD8+ T
       cells by the addition of fresh costimulatory cells. These results
       suggested a new pathway of down-regulation of T-cell proliferation by
       aCD3-activated cytolytic CD8+ T cells.
 DE    Animal  Antibodies/IMMUNOLOGY  Antigens, CD3/*IMMUNOLOGY  Cell
       Division/DRUG EFFECTS  Cells, Cultured  Cytotoxicity, Immunologic
       CD8-Positive T-Lymphocytes/IMMUNOLOGY  Down-Regulation (Physiology)
       Mice  Mice, Inbred BALB C  T-Lymphocytes/*IMMUNOLOGY  JOURNAL ARTICLE

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

