Environmental cues, dendritic cells and the programming of tissue-selective lymphocyte trafficking.
Lymphocytes are imprinted during activation with trafficking programs (combinations of adhesion and chemoattractant receptors) that target their migration to specific tissues and microenvironments. Cytokines contribute, but, for gut and skin, evolution has cleverly adapted external cues from food (vitamin A) and sunlight (ultraviolet-induced vitamin D3) to imprint lymphocyte homing to the small intestines and T cell migration into the epidermis. Dendritic cells are essential: they process the vitamins to their active metabolites (retinoic acid and 1,25(OH)(2)D3) for presentation with antigen to lymphocytes, and they help export environmental cues through lymphatics to draining lymph nodes, to program the trafficking and effector functions of naive T and B cells.
Sigmundsdottir
Hekla
H
Laboratory of Immunology and Vascular Biology, Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA.
Butcher
Eugene C
EC
D000818:Animals; D015815:Cell Adhesion Molecules / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology*; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D007156:Immunologic Memory; D008198:Lymph Nodes / Q000276:immunology; D016201:Receptors, Lymphocyte Homing / Q000502:physiology; D016176:T-Lymphocyte Subsets / Q000502:physiology*
D015815:Cell Adhesion Molecules; D016201:Receptors, Lymphocyte Homing