title: Regulatory role of B cells in a murine model of allergic airway disease.
abstract: Mice sensitized to OVA and subjected to acute OVA aerosol exposures develop allergic airway disease (AAD). However, chronic continuous Ag exposure results in resolution of AAD and the development of local inhalational tolerance (LIT). Because we have previously observed the persistence of B cells in the bronchoalveolar lavage (BAL) and hilar lymph nodes (HLN) at the resolution stage of this model, we investigated the role of B cells in the modulation of AAD. Although B cell-deficient mice developed LIT, adoptive transfer of HLN B cells from LIT mice to OVA-sensitized recipients resulted in attenuated AAD following subsequent OVA aerosol exposure, as determined by reduced BAL leukocytosis and eosinophilia, decreased tissue inflammation, and absent methacholine hyper-responsiveness. In similar adoptive transfer studies, HLN B cells from AAD mice were without effect. The protection transferred by LIT HLN B cells was Ag specific and was associated with accumulation of Foxp3(+) T regulatory cells regionally in BAL and HLN, but not systemically in the spleen. Fluorescent labeling of LIT HLN B cells before adoptive transfer demonstrated that these cells had the capacity to migrate to local inflammatory sites. In vitro assessment demonstrated that the LIT HLN B cells exerted this regulatory effect via TGF-beta induced conversion of CD4(+)CD25(-) T effector cells into functionally suppressive CD4(+)CD25(+)Foxp3(+) T regulatory cells. These findings illustrated a novel regulatory role for regional B cells in AAD and suggested a possible contributory role of B cells, along with other cell types, in the establishment of LIT.
authors.affiliation: Department of Immunology, University of Connecticut Health Center, Framington, CT 06030, USA.
authors.forename: Anurag
authors.initials: A
authors.lastname: Singh
authors.forename: William F
authors.initials: WF
authors.lastname: Carson
authors.forename: Eric R
authors.initials: ER
authors.lastname: Secor
authors.forename: Linda A
authors.initials: LA
authors.lastname: Guernsey
authors.forename: Richard A
authors.initials: RA
authors.lastname: Flavell
authors.forename: Robert B
authors.initials: RB
authors.lastname: Clark
authors.forename: Roger S
authors.initials: RS
authors.lastname: Thrall
authors.forename: Craig M
authors.initials: CM
authors.lastname: Schramm
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D016175:B-Lymphocyte Subsets / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D004195:Disease Models, Animal; D007108:Immune Tolerance; D008168:Lung / Q000166:cytology / Q000276:immunology; D008198:Lymph Nodes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D010047:Ovalbumin / Q000276:immunology; D012130:Respiratory Hypersensitivity / Q000276:immunology* / Q000378:metabolism; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000276:immunology / Q000378:metabolism*
chemical_list: D016212:Transforming Growth Factor beta; D010047:Ovalbumin