title: Candida soluble cell wall beta-glucan facilitates ovalbumin-induced allergic airway inflammation in mice: Possible role of antigen-presenting cells.
abstract: BACKGROUND
  Although fungi have been implicated as initiating/deteriorating factors for allergic asthma, their contributing components have not been fully elucidated. We previously isolated soluble beta-glucan from Candida albicans (CSBG) (Ohno et al., 2007). In the present study, the effects of CSBG exposure on airway immunopathology in the presence or absence of other immunogenic allergen was investigated in vivo, and their cellular mechanisms were analyzed both in vivo and in vitro.
  
  
  METHODS
  In vivo, ICR mice were divided into 4 experimental groups: vehicle, CSBG (25 microg/animal), ovalbumin (OVA: 2 microg/animal), and CSBG + OVA were repeatedly administered intratracheally. The bronchoalveolar lavage cellular profile, lung histology, levels of cytokines and chemokines in the lung homogenates, the expression pattern of antigen-presenting cell (APC)-related molecules in the lung digests, and serum immunoglobulin values were studied. In vitro, the impacts of CSBG (0-12.5 microg/ml) on the phenotype and function of immune cells such as splenocytes and bone marrow-derived dendritic cells (BMDCs) were evaluated in terms of cell proliferation, the surface expression of APC-related molecules, and OVA-mediated T-cell proliferating activity.
  
  
  RESULTS
  In vivo, repeated pulmonary exposure to CSBG induced neutrophilic airway inflammation in the absence of OVA, and markedly exacerbated OVA-related eosinophilic airway inflammation with mucus metaplasia in mice, which was concomitant with the amplified lung expression of Th2 cytokines and IL-17A and chemokines related to allergic response. Exposure to CSBG plus OVA increased the number of cells bearing MHC class II with or without CD80 in the lung compared to that of others. In vitro, CSBG significantly augmented splenocyte proliferation in the presence or absence of OVA. Further, CSBG increased the expression of APC-related molecules such as CD80, CD86, and DEC205 on BMDCs and amplified OVA-mediated T-cell proliferation through BMDCs.
  
  
  CONCLUSIONS
  CSBG potentiates allergic airway inflammation with maladaptive Th immunity, and this potentiation was associated with the enhanced activation of APCs including DC.
authors.affiliation: Environmental Health Sciences Division, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan. inoue.kenichirou@nies.go.jp
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Inoue
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Takano
authors.forename: Eiko
authors.initials: E
authors.lastname: Koike
authors.forename: Rie
authors.initials: R
authors.lastname: Yanagisawa
authors.forename: Toshio
authors.initials: T
authors.lastname: Oda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tamura
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Adachi
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Ishibashi
authors.forename: Naohito
authors.initials: N
authors.lastname: Ohno
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid; D002176:Candida albicans / Q000737:chemistry*; D049109:Cell Proliferation / Q000187:drug effects; D002473:Cell Wall / Q000737:chemistry* / Q000276:immunology*; D016207:Cytokines / Q000032:analysis / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology; D005434:Flow Cytometry; D005802:Genes, MHC Class II / Q000235:genetics; D007073:Immunoglobulin E / Q000276:immunology; D007249:Inflammation / Q000473:pathology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009000:Monocytes / Q000276:immunology; D009093:Mucus / Q000166:cytology / Q000276:immunology; D009504:Neutrophils / Q000276:immunology; D010047:Ovalbumin / Q000276:immunology*; D012130:Respiratory Hypersensitivity / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000276:immunology; D047071:beta-Glucans / Q000737:chemistry* / Q000276:immunology*
chemical_list: D016207:Cytokines; D047071:beta-Glucans; D007073:Immunoglobulin E; D010047:Ovalbumin