title: Dendritic cells from mycobacteria-infected mice inhibits established allergic airway inflammatory responses to ragweed via IL-10- and IL-12-secreting mechanisms.
abstract: Previous studies have demonstrated that Mycobacterium bovis bacillus Calmette-Guerin (BCG) infection can inhibit de novo and established allergen-induced asthma-like responses. The aim of this study was to examine the role of dendritic cells (DCs) in BCG infection-mediated inhibition of established allergy to a common environmental allergen--ragweed. The results showed that adoptive transfer of DCs from BCG-infected mice (DC[BCG]), in contrast to DCs from naive mice (DC[naive]), significantly inhibited established allergic airway eosinophilia and mucus overproduction. The inhibitory effect was correlated with alterations of allergen-driven cytokine and chemokine production as well as VCAM-1 expression in the lung. Flow cytometric analysis showed higher surface expression of CD8alpha and costimulatory markers in DC(BCG) than in DC(naive). Moreover, DC(BCG) produced significantly higher levels of IL-10 and IL-12 and expressed higher levels of TLRs than did DC(naive). Furthermore, blockade of IL-10 or IL-12 significantly reversed the inhibitory effect of DC(BCG) on established allergic airway inflammation and Th2 cytokine responses. These findings suggest that DCs play a crucial role in infection-mediated inhibition of established allergic responses, and IL-10 and IL-12 production by these DCs may be a major mechanism for the inhibition.
authors.affiliation: Immune Regulation of Allergy Research Group, Department of Medical Microbiology, Winnipeg, Mantioba, Canada.
authors.forename: Laura
authors.initials: L
authors.lastname: Bilenki
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Gao
authors.forename: Shuhe
authors.initials: S
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Yijun
authors.initials: Y
authors.lastname: Fan
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Han
authors.forename: Hongyu
authors.initials: H
authors.lastname: Qiu
authors.forename: Xi
authors.initials: X
authors.lastname: Yang
mesh_terms: D019264:Adoptive Transfer; D031164:Ambrosia / Q000276:immunology; D000818:Animals; D002469:Cell Separation; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression; D020869:Gene Expression Profiling; D016753:Interleukin-10 / Q000096:biosynthesis* / Q000276:immunology; D018664:Interleukin-12; D051379:Mice; D008810:Mice, Inbred C57BL; D009163:Mycobacterium bovis / Q000276:immunology; D012130:Respiratory Hypersensitivity / Q000276:immunology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051193:Toll-Like Receptors / Q000096:biosynthesis; D014376:Tuberculosis / Q000276:immunology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000276:immunology
chemical_list: D051193:Toll-Like Receptors; D019010:Vascular Cell Adhesion Molecule-1; D016753:Interleukin-10; D018664:Interleukin-12