title: S1P1 receptor expression regulates emergence of NKT cells in peripheral tissues.
abstract: The S1P1 receptor, on the surface of lymphocytes and endothelial cells, regulates the unique trafficking behavior of certain lymphocyte populations. We have examined whether the S1P1 receptor also dictates the distinctive tissue distribution of V alpha14-J alpha18 natural killer T (NKT) cells, whose trafficking pattern is not well understood. Mice (TCS1P1 KO) were established with a conditional deletion of the S1P1 receptor in thymocytes that included precursors of NKT cells. Within the thymus, NKT cells were found at normal or increased levels, indicating that S1P1 receptor expression was dispensable for NKT cell development. However, substantially reduced numbers of NKT cells were detected in the peripheral tissues of the TCS1P1 KO mice. Short-term S1P1 deletion after NKT cells had established residence in the periphery did not substantially alter their distribution in tissues, except for a partial decrease in the spleen. FTY720, a S1P1 receptor ligand that has potent effects on the trafficking of conventional T cells, did not alter the preexisting distribution of NKT cells within peripheral tissues of wild-type mice. Our results indicate that the S1P1 receptor expression on NKT cells is dispensable for development within thymus but is essential for the establishment of their tissue residency in the periphery.
authors.affiliation: Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-1821, USA.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Allende
authors.forename: Dapeng
authors.initials: D
authors.lastname: Zhou
authors.forename: Danielle N
authors.initials: DN
authors.lastname: Kalkofen
authors.forename: Sonia
authors.initials: S
authors.lastname: Benhamed
authors.forename: Galina
authors.initials: G
authors.lastname: Tuymetova
authors.forename: Christine
authors.initials: C
authors.lastname: Borowski
authors.forename: Albert
authors.initials: A
authors.lastname: Bendelac
authors.forename: Richard L
authors.initials: RL
authors.lastname: Proia
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D017931:DNA Primers; D005434:Flow Cytometry; D007694:Killer Cells, Natural / Q000166:cytology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016133:Polymerase Chain Reaction; D049349:Receptors, Lysosphingolipid / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D015398:Signal Transduction