title: T cell costimulation by chemokine receptors.
abstract: Signals mediated by chemokine receptors may compete with T cell receptor stop signals and determine the duration of T cell-antigen-presenting cell interactions. Here we show that during T cell stimulation by antigen-presenting cells, T cell chemokine receptors coupled to G(q) and/or G(11) protein were recruited to the immunological synapse by a G(i)-independent mechanism. When chemokine receptors were sequestered at the immunological synapse, T cells became insensitive to chemotactic gradients, formed more stable conjugates and finally responded with enhanced proliferation and cytokine production. We suggest that chemokine receptor trapping at the immunological synapse enhances T cell activation by improving T cell-antigen-presenting cell attraction and impeding the 'distraction' of successfully engaged T cells by other chemokine sources.
authors.affiliation: Venetian Institute of Molecular Medicine and Department of Biomedical Science, University of Padua, 35100 Padua, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Molon
authors.forename: Giorgia
authors.initials: G
authors.lastname: Gri
authors.forename: Monica
authors.initials: M
authors.lastname: Bettella
authors.forename: Concepción
authors.initials: C
authors.lastname: Gómez-Moutón
authors.forename: Antonio
authors.initials: A
authors.lastname: Lanzavecchia
authors.forename: Carlos
authors.initials: C
authors.lastname: Martínez-A
authors.forename: Santos
authors.initials: S
authors.lastname: Mañes
authors.forename: Antonella
authors.initials: A
authors.lastname: Viola
mesh_terms: D000938:Antigen-Presenting Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D002448:Cell Adhesion; D002478:Cells, Cultured; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology*; D011485:Protein Binding; D019707:Receptors, Chemokine / Q000378:metabolism*; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*
chemical_list: D019707:Receptors, Chemokine; D043802:GTP-Binding Protein alpha Subunits, Gq-G11