title: Skin-homing CLA+ T cells and regulatory CD25+ T cells represent major subsets of human peripheral blood memory T cells migrating in response to CCL1/I-309.
abstract: Functionally distinct T cell subsets exhibit specific chemokine receptor profiles that regulate their tissue localization. Here, we show that human peripheral blood CD4(+) and CD8(+) cutaneous (CLA(+)), but not intestinal memory (integrin beta(7) (+)) nor IL-4-producing T cells, represent major subpopulations of circulating T cells that specifically migrate in response to the chemokine I-309/CCL1 by virtue of CCR8 expression. Expression of CCR8 is markedly up-regulated upon activation and in vitro culture of human CLA(+) T cells, suggesting the involvement of CCR8 in localization of cutaneous memory T cells to the skin. Interestingly, amongst circulating memory CD4(+)CD45RO(+) T cells, chemotactic responsiveness to CCL1 is restricted to cells expressing CD25 and/or CLA surface markers for regulatory T cells (Treg) and skin-homing T cells and maximal responsiveness is observed on CLA(+)CD25(+)T cells. Such pattern of CCL1 responsiveness suggests that the CCR8/CCL1 axis may regulate trafficking of cutaneous Treg and memory T cells into the skin.
authors.affiliation: BioXell, Milano, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Colantonio
authors.forename: Andrea
authors.initials: A
authors.lastname: Iellem
authors.forename: Francesco
authors.initials: F
authors.lastname: Sinigaglia
authors.forename: Daniele
authors.initials: D
authors.lastname: D'Ambrosio
mesh_terms: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D002460:Cell Line; D054402:Chemokine CCL1; D019742:Chemokines, CC / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D006801:Humans; D007156:Immunologic Memory; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000378:metabolism*; D054401:Receptors, CCR8; D019707:Receptors, Chemokine / Q000378:metabolism; D015375:Receptors, Interleukin-2 / Q000378:metabolism*; D012867:Skin / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; C065971:CCL1 protein, human; C103330:CCR8 protein, human; C063419:CTAGE1 protein, human; D054402:Chemokine CCL1; D019742:Chemokines, CC; D008562:Membrane Glycoproteins; D054401:Receptors, CCR8; D019707:Receptors, Chemokine; D015375:Receptors, Interleukin-2