title: All-trans retinoic acid mediates enhanced T reg cell growth, differentiation, and gut homing in the face of high levels of co-stimulation.
abstract: We demonstrate that all-trans retinoic acid (RA) induces FoxP3(+) adaptive T regulatory cells (A-Tregs) to acquire a gut-homing phenotype (alpha 4 beta 7(+) CC chemokine receptor 9(+)) and the capacity to home to the lamina propria of the small intestine. Under conditions that favor the differentiation of A-Tregs (transforming growth factor-beta1 and interleukin 2) in vitro, the inclusion of RA induces nearly all activated CD4(+) T cells to express FoxP3 and greatly increases the accumulation of these cells. In the absence of RA, A-Treg differentiation is abruptly impaired by proficient antigen presenting cells or through direct co-stimulation. In the presence of RA, A-Treg generation occurs even in the presence of high levels of co-stimulation, with RA attenuating co-stimulation from interfering from FoxP3 induction. The recognition that RA induces gut imprinting, together with our finding that it enhances A-Treg conversion, differentiation, and expansion, indicates that RA production in vivo may drive both the imprinting and A-Treg development in the face of overt inflammation.
authors.affiliation: Department of Microbiology and Immunology, Dartmouth Medical School and Norris Cotton Cancer Center, Lebanon, NH 03756, USA.
authors.forename: Micah J
authors.initials: MJ
authors.lastname: Benson
authors.forename: Karina
authors.initials: K
authors.lastname: Pino-Lagos
authors.forename: Mario
authors.initials: M
authors.lastname: Rosemblatt
authors.forename: Randolph J
authors.initials: RJ
authors.lastname: Noelle
mesh_terms: D000818:Animals; D018122:B7-1 Antigen / Q000096:biosynthesis; D051940:B7-2 Antigen / Q000096:biosynthesis; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D002454:Cell Differentiation; D018392:Genomic Imprinting; D007421:Intestine, Small / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D013601:T-Lymphocytes / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D014212:Tretinoin / Q000502:physiology*
chemical_list: D018122:B7-1 Antigen; D051940:B7-2 Antigen; D053773:Transforming Growth Factor beta1; D014212:Tretinoin