       Document 0130
 DOCN  M95A0130
 TI    Functional significance of CD23- on CD23-transfected Th2 clone.
 DT    9510
 AU    Nambu M; Hagen M; Sandor M; Sacco RE; Kwack K; Lynch RG; Department of
       Pathology, College of Medicine, University of Iowa,; Iowa City 52242,
       USA.
 SO    Immunol Lett. 1995 Jan;44(2-3):163-7. Unique Identifier : AIDSLINE
       MED/95317800
 AB    CD23, a low-affinity IgE Fc receptor, is not displayed on most resting T
       cells but its expression has been shown to be transiently induced in
       vivo and in vitro on some CD4+ T cells [1-4] and in vivo on CD8+ T cells
       by IgE-secreting hybridoma tumors [5]. To investigate the functional
       role of CD23 on T cells, we inserted a CD23 construct into an expression
       vector driven by a CD2 promoter and transfected it into a murine Th2
       clone D10.G4.1 (D10). We stimulated the transfected D10 cells
       (D10.3M.24) with anti-TCR antibody in the presence or absence of IgE,
       and measured IL-4, IL-5 and IL-6 production in the culture supernatants.
       Activation of D10.3M.24 cells by anti-TCR antibody induced greater
       levels of IL-4, IL-5 and IL-6 production, when the TCR and CD23 were
       co-crosslinked by TNP anti-TCR and IgE anti-TNP antibodies. IgG anti-TNP
       antibody did not enhance lymphokine production by D10.3M.24 cells. The
       enhanced lymphokine production by IgE was blocked by monoclonal
       anti-CD23 antibody. IgE anti-TNP antibody did not enhance lymphokine
       production by the wild-type D10 cells induced by TNP anti-TCR antibody.
       These studies show that when co-crosslinked with the TCR, CD23 can
       modulate the lymphokine production in activated Th2 cells. Since CD23
       binds to IgE and also binds to CD21 [6], a complement receptor commonly
       expressed on B cells, T-cell CD23 could play an immunoregulatory role
       during cognate T-B cell interaction and during IgE antibody responses.
 DE    Animal  Antibodies/PHARMACOLOGY  Antigens, Surface/GENETICS/METABOLISM
       B-Lymphocytes/IMMUNOLOGY  Chimeric Proteins/METABOLISM  Clone Cells
       Interleukins/*BIOSYNTHESIS  Mice  Models, Immunological  Polymerase
       Chain Reaction  Precipitin Tests  Receptors, Antigen,
       T-Cell/IMMUNOLOGY/*METABOLISM  Receptors, IgE/GENETICS/*METABOLISM
       Support, U.S. Gov't, P.H.S.  Th2 Cells/DRUG EFFECTS/*IMMUNOLOGY
       Transfection  JOURNAL ARTICLE

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

