title: TECK, an efficacious chemoattractant for human thymocytes, uses GPR-9-6/CCR9 as a specific receptor.
abstract: Chemokines regulate leukocytes trafficking in normal and inflammation conditions. Thymus-seeding progenitors are made in bone marrow and migrate to the thymus where they undergo their maturation to antigen-specific T cells. Immature T cells are in thymic cortex, while mature thymocytes are in medulla. Chemokines may be important for homing of thymus-seeding progenitors, and/or differential thymocyte localization in thymus. Here we report that GPR-9-6, now called CC chemokine receptor 9 (CCR9), is a receptor for thymus-expressed chemokine, TECK. Among a panel of chemokines tested, TECK specifically induced calcium flux in CCR9-expressing cell lines. We also showed that TECK efficaciously induced chemotaxis of immature CD4(+)CD8(+) double-positive, and mature CD4(+) and CD8(+) single-positive human thymocytes. Our data suggest that TECK/CCR9 interaction may play a pivotal role in T-cell migration in the thymus.
authors.affiliation: Department of Microbiology, Walther Oncology Center, Indianapolis, IN, USA.
authors.forename: B S
authors.initials: BS
authors.lastname: Youn
authors.forename: C H
authors.initials: CH
authors.lastname: Kim
authors.forename: F O
authors.initials: FO
authors.lastname: Smith
authors.forename: H E
authors.initials: HE
authors.lastname: Broxmeyer
mesh_terms: D000595:Amino Acid Sequence; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D002478:Cells, Cultured; D019742:Chemokines, CC / Q000502:physiology*; D002634:Chemotaxis, Leukocyte; D006801:Humans; D007668:Kidney; D007700:Kinetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D054388:Receptors, CCR; D019707:Receptors, Chemokine / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013601:T-Lymphocytes / Q000276:immunology / Q000502:physiology*
chemical_list: C119309:CC chemokine receptor 9; C108074:CCL25 protein, human; D019742:Chemokines, CC; D054388:Receptors, CCR; D019707:Receptors, Chemokine; D011994:Recombinant Proteins; D002118:Calcium