title: Antibacterial and neutralizing effect of human β-defensins on Enterococcus faecalis and Enterococcus faecalis lipoteichoic acid.
abstract: BACKGROUND
  Enterococcus faecalis is frequently found in the root canal of teeth, is a major microorganism of endodontic therapy failure, and is associated with chronic apical periodontitis. Human β-defensins (HBDs) are known to play critical roles in defending the host against infectious microbes and producing dental pulp in healthy and patients. The purpose of the present study was to investigate the bactericidal and neutralizing effects of HBDs on E. faecalis and E. faecalis lipoteichoic acid (Ef LTA) as a major virulence factor of E. faecalis.
  
  
  METHODS
  HBD-1, -2, -3, and -4 were synthesized and investigated the susceptibility against E. faecalis. Also, the neutralizing effects of HBDs on cytokine and intercellular adhesion molecule 1 (ICAM-1) expression by activity of E. faecalis and Ef LTA were analyzed using enzyme-linked immunosorbent assay and flow cytometry.
  
  
  RESULTS
  HBD-1 and -2 were weakly susceptible, and HBD-3 and HBD-4 were strongly susceptible to E. faecalis. All of the HBDs exhibited neutralizing effects on the activity of Ef LTA, and HBD-3 strongly neutralized the activity of E. faecalis in tumor necrosis factor-α, interleukin-8, and ICAM-1 expression. The neutralizing effects of HBDs were to inhibit E. faecalis or Ef LTA binding to the host cells.
  
  
  CONCLUSIONS
  These results suggest that the induction of HBDs might have great potential as endodontic therapeutic agents.
authors.affiliation: Department of Oral Microbiology and Immunology, College of Dentistry, Dankook University, Cheonan, Republic of Korea.
authors.forename: Sung-Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Dong-Heon
authors.initials: DH
authors.lastname: Baek
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001422:Bacterial Adhesion / Q000187:drug effects; D001431:Bacteriological Techniques; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000472:pathogenicity; D005434:Flow Cytometry; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000187:drug effects; D016209:Interleukin-8 / Q000037:antagonists & inhibitors; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors*; D009000:Monocytes / Q000187:drug effects / Q000276:immunology / Q000382:microbiology; D053719:Tandem Mass Spectrometry; D013682:Teichoic Acids / Q000037:antagonists & inhibitors*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors; D037521:Virulence Factors / Q000037:antagonists & inhibitors*; D023083:beta-Defensins / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; C406407:DEFB1 protein, human; C422950:DEFB103A protein, human; C106641:DEFB4A protein, human; D016209:Interleukin-8; D008070:Lipopolysaccharides; D013682:Teichoic Acids; D014409:Tumor Necrosis Factor-alpha; D037521:Virulence Factors; D023083:beta-Defensins; D018799:Intercellular Adhesion Molecule-1; C009900:lipoteichoic acid