title: TCR signaling induces selective exclusion of CD43 from the T cell-antigen-presenting cell contact site.
abstract: CD43, a large highly glycosylated molecule, is arguably the most abundant molecule on the surface of T cells. Nevertheless, the function of CD43 remains unclear. Utilizing fluorescence microscopy, we find that CD43 is excluded from the T cell-APC contact site. This exclusion is Ag dependent since optimal CD43 exclusion requires Ag-pulsed APC, and since signaling through CD3, in the absence of any other receptor ligand interactions, can induce the modulation of CD43. These data suggest that CD43 may function as a barrier to nonspecific T cell-APC interactions that is removed as a result of T cell activation. Exclusion from the interaction site is a unique feature of CD43 and not universally found for all large highly glycosylated molecules since CD45 is not excluded. Thus, CD43 may represent a novel regulatory molecule on the T cell surface that can direct T cell interactions by changing its location on the cell surface.
authors.affiliation: Department of Medicine, University of Chicago, IL 60637, USA. asperlin@medicine.bsd.uchicago.edu
authors.forename: A I
authors.initials: AI
authors.lastname: Sperling
authors.forename: J R
authors.initials: JR
authors.lastname: Sedy
authors.forename: N
authors.initials: N
authors.lastname: Manjunath
authors.forename: A
authors.initials: A
authors.lastname: Kupfer
authors.forename: B
authors.initials: B
authors.lastname: Ardman
authors.forename: J K
authors.initials: JK
authors.lastname: Burkhardt
mesh_terms: D000938:Antigen-Presenting Cells / Q000276:immunology*; D015703:Antigens, CD; D002450:Cell Communication; D002462:Cell Membrane / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D017493:Leukocyte Common Antigens / Q000032:analysis; D051917:Leukosialin; D008213:Lymphocyte Activation; D046911:Macromolecular Substances; D009038:Motion; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D012795:Sialoglycoproteins / Q000378:metabolism*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D051917:Leukosialin; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell; C465014:SPN protein, human; D012795:Sialoglycoproteins; D017493:Leukocyte Common Antigens