title: Density of dendritic cells in the human tracheal mucosa is age dependent and site specific.
abstract: BACKGROUND
  The mucosal immune system undergoes extensive changes in early childhood in response to environmental stimuli. Dendritic cells (DC) play a major role in the development of the immune system. However, few data exist on the influence of continuous environmental stimulation on the distribution and phenotype of human airway DC.
  
  
  METHODS
  Human tissue samples are mostly paraffin embedded which limits the use of several antibodies, and respiratory tissue for cryopreservation is difficult to obtain. Human frozen post mortem tracheal tissue was therefore used for this study. Only samples with epithelial adherence to the basement membrane were included (n = 34). Immunohistochemical staining and sequential overlay immunofluorescence were performed with DC-SIGN and a panel of leucocyte markers co-expressed by DC.
  
  
  RESULTS
  DC detected in the human tracheal mucosa using DC-SIGN correlated with the expression of HLA-DR, co-stimulatory and adhesion molecules. Higher cell densities were found at the ventral tracheal site of patients older than 1 year than in infants in the first year of life.
  
  
  CONCLUSIONS
  The increasing population of mucosal DC with age could reflect immunological maturation.
authors.affiliation: Functional and Applied Anatomy, Medical School of Hannover, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany. tschernig.thomas@mh-hannover.de
authors.forename: T
authors.initials: T
authors.lastname: Tschernig
authors.forename: V C
authors.initials: VC
authors.lastname: de Vries
authors.forename: A S
authors.initials: AS
authors.lastname: Debertin
authors.forename: A
authors.initials: A
authors.lastname: Braun
authors.forename: T
authors.initials: T
authors.lastname: Walles
authors.forename: F
authors.initials: F
authors.lastname: Traub
authors.forename: R
authors.initials: R
authors.lastname: Pabst
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D003713:Dendritic Cells / Q000166:cytology*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007111:Immunity, Cellular; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D020545:Respiratory Mucosa / Q000166:cytology*; D014132:Trachea / Q000166:cytology*