title: 1,25-dihydroxyvitamin D3 enhances the ability of transferred CD4+ CD25+ cells to modulate T helper type 2-driven asthmatic responses.
abstract: The severity of allergic diseases may be modified by vitamin D. However, the immune pathways modulated by the active form of vitamin D, 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], are yet to be fully elucidated. In this study, naturally occurring CD4(+) CD25(+) cells from the skin-draining lymph nodes (SDLN) of mice treated with topical 1,25(OH)(2)D(3) had an increased ability to suppress T helper type 2 (Th2) -skewed immune responses. CD4(+) CD25(+) cells transferred from mice treated with topical 1,25(OH)(2)D(3) into ovalbumin (OVA) -sensitized mice challenged intranasally with OVA 18 hr later, significantly suppressed the capacity of airway-draining lymph node (ADLN) cells to proliferate and secrete cytokines in response to further OVA stimulation ex vivo. The CD4(+) CD25(+) cells from 1,25(OH)(2)D(3)-treated mice also reduced airway hyperresponsiveness and the proportions of neutrophils and eosinophils in bronchoalveolar lavage fluid (BALF). To test the effect of 1,25(OH)(2)D(3) on cells able to respond to a specific antigen, CD4(+) CD25(+) cells were purified from the SDLN of OVA-T-cell receptor (TCR) transgenic mice treated 4 days earlier with topical 1,25(OH)(2)D(3). CD4(+) CD25(+) cells from OVA-TCR mice treated with 1,25(OH)(2)D(3) were able to alter BALF cell content and suppress ADLN responses to a similar degree to those cells from non-transgenic mice, suggesting that the effect of 1,25(OH)(2)D(3) was not related to TCR signalling. In summary, topical 1,25(OH)(2)D(3) increased the regulatory capacity of CD4(+) CD25(+) cells from the SDLN to suppress Th2-mediated allergic airway disease. This work highlights how local 1,25(OH)(2)D(3) production by lung epithelial cells may modulate the suppressive activity of local regulatory T cells.
authors.affiliation: Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth, Western Australia, Australia. shelleyg@ichr.uwa.edu.au
authors.forename: Shelley
authors.initials: S
authors.lastname: Gorman
authors.forename: Melinda A
authors.initials: MA
authors.lastname: Judge
authors.forename: Jennifer T
authors.initials: JT
authors.lastname: Burchell
authors.forename: Debra J
authors.initials: DJ
authors.lastname: Turner
authors.forename: Prue H
authors.initials: PH
authors.lastname: Hart
mesh_terms: D000818:Animals; D002117:Calcitriol / Q000096:biosynthesis / Q000276:immunology* / Q000494:pharmacology; D004804:Eosinophils / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D005260:Female; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology; D008198:Lymph Nodes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology / Q000378:metabolism; D012130:Respiratory Hypersensitivity / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D012867:Skin / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism / Q000473:pathology / Q000637:transplantation; D018418:Th2 Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: C508018:Il2ra protein, mouse; D053645:Interleukin-2 Receptor alpha Subunit; D011948:Receptors, Antigen, T-Cell; D002117:Calcitriol