title: Surfactant Protein D modulates allergen particle uptake and inflammatory response in a human epithelial airway model.
abstract: BACKGROUND
  Allergen-containing subpollen particles (SPP) are released from whole plant pollen upon contact with water or even high humidity. Because of their size SPP can preferentially reach the lower airways where they come into contact with surfactant protein (SP)-D. The aim of the present study was to investigate the influence of SP-D in a complex three-dimensional human epithelial airway model, which simulates the most important barrier functions of the epithelial airway. The uptake of SPP as well as the secretion of pro-inflammatory cytokines was investigated.
  
  
  METHODS
  SPP were isolated from timothy grass and subsequently fluorescently labeled. A human epithelial airway model was built by using human Type II-pneumocyte like cells (A549 cells), human monocyte derived macrophages as well as human monocyte derived dendritic cells. The epithelial cell model was incubated with SPP in the presence and absence of surfactant protein D. Particle uptake was evaluated by confocal microscopy and advanced computer-controlled analysis. Finally, human primary CD4+ T-Cells were added to the epithelial airway model and soluble mediators were measured by enzyme linked immunosorbent assay or bead array.
  
  
  RESULTS
  SPP were taken up by epithelial cells, macrophages, and dendritic cells. This uptake coincided with secretion of pro-inflammatory cytokines and chemokines. SP-D modulated the uptake of SPP in a cell type specific way (e.g. increased number of macrophages and epithelial cells, which participated in allergen particle uptake) and led to a decreased secretion of pro-inflammatory cytokines.
  
  
  CONCLUSIONS
  These results display a possible mechanism of how SP-D can modulate the inflammatory response to inhaled allergen.
authors.affiliation: Fraunhofer Institute of Toxicology and Experimental Medicine, Nikolai-Fuch-Str 1, 30635 Hannover, Germany. carsten.schleh@web.de
authors.forename: Carsten
authors.initials: C
authors.lastname: Schleh
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Rothen-Rutishauser
authors.forename: Fabian
authors.initials: F
authors.lastname: Blank
authors.forename: Hans D
authors.initials: HD
authors.lastname: Lauenstein
authors.forename: Matthias
authors.initials: M
authors.lastname: Nassimi
authors.forename: Norbert
authors.initials: N
authors.lastname: Krug
authors.forename: Armin
authors.initials: A
authors.lastname: Braun
authors.forename: Veit J
authors.initials: VJ
authors.lastname: Erpenbeck
authors.forename: Peter
authors.initials: P
authors.lastname: Gehr
authors.forename: Jens M
authors.initials: JM
authors.lastname: Hohlfeld
mesh_terms: D000485:Allergens / Q000276:immunology / Q000378:metabolism; D056809:Alveolar Epithelial Cells / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D001249:Asthma / Q000276:immunology / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D018920:Coculture Techniques; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000378:metabolism*; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D031784:Phleum / Q000276:immunology / Q000378:metabolism; D011058:Pollen / Q000276:immunology / Q000378:metabolism; D037663:Pulmonary Surfactant-Associated Protein D / Q000276:immunology / Q000378:metabolism*; D051381:Rats
chemical_list: D000485:Allergens; D016207:Cytokines; D037663:Pulmonary Surfactant-Associated Protein D