title: Specificity of antimicrobial peptide LL-37 to neutralize periodontopathogenic lipopolysaccharide activity in human oral fibroblasts.
abstract: BACKGROUND
  The antimicrobial peptide LL-37 is known to have a potent lipopolysaccharide (LPS)-neutralizing activity in various cell types. Because of observed heterogeneity within periodontopathogenic LPS, the authors hypothesized that LL-37 had specificity to neutralize such LPS activity. The present study, therefore, aims to investigate the LPS-neutralizing activity of LL-37 to various periodontopathogenic LPS in interleukin-8 (IL-8) production after challenging them in human oral fibroblasts.
  
  
  METHODS
  Human periodontal ligament fibroblasts (PDLF) and gingival fibroblasts (GF) were cultured from biopsies of periodontal ligament and gingival tissues. After cell confluence in 24-well plates, LPS (10 μg/mL) from Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans were added with or without LL-37 (10 μg/mL). After 18 hours, the supernatant was collected and analyzed in IL-8 production by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  All periodontopathogenic LPS statistically significantly induced IL-8 production in both PDLF and GF (P <0.01). After neutralization with LL-37, both PDLF and GF showed a statistically significant reduction in IL-8 production compared with LPS-treated groups without LL-37 (P <0.01), and the percentage of reduction in IL-8 production in PDLF appeared to be higher than in GF. In addition, the percentage of reduction in IL-8 production varied considerably according to each periodontopathogenic LPS.
  
  
  CONCLUSIONS
  The antimicrobial peptide LL-37 had an ability to suppress periodontopathogenic LPS-induced IL-8 production in both PDLF and GF. Its LPS-neutralizing activity revealed specificity to periodontopathogenic LPS and seemed to be dependent on the heterogeneity within LPS between different genera.
authors.affiliation: Department of Periodontology, The Nippon Dental University, School of Life Dentistry at Niigata, Chuo-ku, Niigata, Japan. bukung@ngt.ndu.ac.jp
authors.forename: Wiroj
authors.initials: W
authors.lastname: Suphasiriroj
authors.forename: Masato
authors.initials: M
authors.lastname: Mikami
authors.forename: Hiromi
authors.initials: H
authors.lastname: Shimomura
authors.forename: Soh
authors.initials: S
authors.lastname: Sato
mesh_terms: D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000502:physiology; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000502:physiology; D005347:Fibroblasts / Q000187:drug effects*; D016967:Fusobacterium nucleatum / Q000502:physiology; D005881:Gingiva / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D016209:Interleukin-8 / Q000037:antagonists & inhibitors; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000032:analysis / Q000037:antagonists & inhibitors*; D010510:Periodontal Diseases / Q000382:microbiology*; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects*; D016966:Porphyromonas gingivalis / Q000502:physiology; D018713:Prevotella intermedia / Q000502:physiology; D013045:Species Specificity; D055815:Young Adult; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D016209:Interleukin-8; D008070:Lipopolysaccharides; C440499:lipopolysaccharide, Escherichia coli O111 B4; D054804:Cathelicidins