title: Cellular uptake and processing of enamel matrix derivative by human periodontal ligament fibroblasts.
abstract: OBJECTIVE
  Enamel matrix derivative (EMD), is an extract of porcine developing enamel matrix. Its commercialised form Emdogain, is claimed to stimulate periodontal regeneration by recapitulating original developmental processes, although the mechanism remains unclear. Our objective was to investigate interactions between EMD and human periodontal ligament (HPDL) fibroblasts in vitro.
  
  
  METHODS
  HPDL fibroblasts were cultured in the presence of fluorescently labelled EMD and cellular EMD uptake was monitored using confocal laser scanning microscopy and immunohistochemistry. Internalised EMD proteins were characterised using SDS-PAGE.
  
  
  RESULTS
  EMD was internalised by HPDL fibroblasts leading to the appearance of multiple, vesicle-like structure in the cytoplasm. The internalised protein was composed mainly of the major 20kDa amelogenin component of EMD which was subsequently processed with time to generate a cumulative 5kDa component.
  
  
  CONCLUSIONS
  Cellular uptake and subsequent intracellular processing of EMD components by dental mesenchymal cells may play a role in EMD bioactivity and in part explain the turnover of Emdogain when placed clinically.
authors.affiliation: Department of Oral Biology, Leeds Dental Institute, University of Leeds, Leeds, England, United Kingdom.
authors.forename: James D
authors.initials: JD
authors.lastname: Lees
authors.forename: Colin
authors.initials: C
authors.lastname: Robinson
authors.forename: Roger C
authors.initials: RC
authors.lastname: Shore
authors.forename: Michael L
authors.initials: ML
authors.lastname: Paine
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Brookes
mesh_terms: D053523:Amelogenin / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D003746:Dental Enamel Proteins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005347:Fibroblasts / Q000378:metabolism*; D048091:Guided Tissue Regeneration / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D018613:Microscopy, Confocal; D010513:Periodontal Ligament / Q000166:cytology* / Q000378:metabolism; D013552:Swine
chemical_list: D053523:Amelogenin; D003746:Dental Enamel Proteins