title: CXCR4-CCR5: a couple modulating T cell functions.
abstract: Chemokines and their receptors direct leukocyte migration among blood, lymph and tissues. Evidence has recently accumulated that, besides their chemotactic functions, chemokine receptors are highly versatile players that fine tune immune responses. During human T cell activation by antigen-presenting cells, the chemokine receptors CCR5 and CXCR4 are recruited into the immunological synapse, where they deliver costimulatory signals. However, the molecular mechanisms allowing signaling versatility of chemokine receptors are unknown. Here, we describe the functional interaction between CXCR4 and CCR5 to exert specific biological functions and modulate T lymphocyte responses. We demonstrate that simultaneous expression and cooperation between CCR5 and CXCR4 are required for chemokine-induced T cell costimulation at the immunological synapse. In addition, we provide evidence for a physical association of the two receptors in a signaling complex that activates distinct T cell functions. We suggest that cooperation between receptors represents one key strategy for the functional plasticity of chemokines.
authors.affiliation: Venetian Institute of Molecular Medicine, via Orus 2, 35129 Padua, Italy.
authors.forename: Rita Lucia
authors.initials: RL
authors.lastname: Contento
authors.forename: Barbara
authors.initials: B
authors.lastname: Molon
authors.forename: Cedric
authors.initials: C
authors.lastname: Boularan
authors.forename: Tullio
authors.initials: T
authors.lastname: Pozzan
authors.forename: Santos
authors.initials: S
authors.lastname: Manes
authors.forename: Stefano
authors.initials: S
authors.lastname: Marullo
authors.forename: Antonella
authors.initials: A
authors.lastname: Viola
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D019281:Dimerization; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D019169:Jurkat Cells; D008164:Luminescent Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008213:Lymphocyte Activation; D018613:Microscopy, Confocal; D046912:Multiprotein Complexes; D019713:Receptors, CCR5 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019718:Receptors, CXCR4 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D014162:Transfection
chemical_list: C527276:CXCR4 protein, human; D008164:Luminescent Proteins; D046912:Multiprotein Complexes; D019713:Receptors, CCR5; D019718:Receptors, CXCR4; D043562:Receptors, G-Protein-Coupled; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins