title: Human β-defensin-2 induction in nasal mucosa after administration of bacterial lysates.
abstract: OBJECTIVE
  The airway epithelium produces antimicrobial peptides (AMPs) that prevent colonization of host tissues by a wide range of pathogens. Human β-defensin 2 (hBD-2) is one of the most well-documented AMPs in humans. Several bacterial products can induce production of this peptide. Bacterial immunostimulants containing bacterial lysates have long been used in the treatment of respiratory infections, but their effects on hBD-2 release have not been investigated. We undertook this study to induce production of hBD-2 after stimulation of the nasal mucosa with bacterial lysates.
  
  
  METHODS
  A nasal lavage (NL) was performed in 12 healthy volunteers under basal conditions and after a nasal challenge with separate and subsequent stimuli with either bacterial lysates (20 million), cholecalciferol (400 IU), or sham-challenge with glycerol plus isotonic saline solution. Immunohistochemistry was performed in nasal biopsies 48 h after stimulation with bacterial lysates to identify the presence of hBD-2.
  
  
  RESULTS
  Increased levels of hBD-2 (4668.99 ± 2829.33 pg/mL) were measured with ELISA in NL fluids following bacterial challenge. However, hBD-2 concentrations were below the limit of detection in NL fluids at baseline and after the administration of cholecalciferol or the sham-challenge. Through immunohistochemistry, hBD-2 was predominantly localized to the epithelium.
  
  
  CONCLUSIONS
  hBD-2 can be induced in the nasal mucosa after administration of bacterial lysates. Stimulation of the innate immune system to produce hBD-2 could be used to prevent or even treat infections caused by respiratory pathogens.
authors: Superior School of Medicine, National Polytechnic Institute (ESM-IPN), Mexico City, Mexico.
authors: Eduardo
authors: E
authors: Guaní-Guerra
authors: María Cristina
authors: MC
authors: Negrete-García
authors: Rosalía
authors: R
authors: Montes-Vizuet
authors: Juan
authors: J
authors: Asbun-Bojalil
authors: Luis M
authors: LM
authors: Terán
mesh_terms: D000293:Adolescent; D000328:Adult; D001419:Bacteria / Q000276:immunology*; D002457:Cell Extracts / Q000276:immunology*; D002762:Cholecalciferol / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D008297:Male; D017817:Nasal Lavage Fluid / Q000737:chemistry; D009297:Nasal Mucosa / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D055815:Young Adult; D023083:beta-Defensins / Q000737:chemistry / Q000378:metabolism*; D000095983:Bacterial Lysates
chemical_list: D002457:Cell Extracts; D002762:Cholecalciferol; D023083:beta-Defensins; C030259:Broncho-Vaxom; D000095983:Bacterial Lysates; C106641:DEFB4A protein, human