title: An Experimental Study on Guided Bone Regeneration Using a Polylactide-co-glycolide Membrane-Immobilized Conditioned Medium.
abstract: OBJECTIVE
  To investigate whether bone regeneration can be accelerated by using a conditioned medium (CM) and guided bone regeneration (GBR) technique.
  
  
  METHODS
  CM was harvested from rat bone marrow stromal cells (BMSCs). The components of CM were immobilized using a polylactide-co-glycolide (PLGA) membrane treated with and without 0.5 mol/L sodium hydroxide (NaOH) to elevate the hydrophilicity. Four experimental groups were prepared: PLGA membrane treated with (1) phosphate-buffered saline (PBS; PBS-M), (2) PBS and 0.5 mol/L NaOH (hydrophilic treatment; PBS-HM), (3) CM (CM-M), and (4) CM and 0.5 mol/L NaOH (CM-HM). These experimental membranes were observed using scanning electron microscopy. Proteins derived from BMSCs immobilized on the PLGA membrane were detected with liquid chromatography-tandem mass spectrometry (LC/MS/MS). Cell proliferation and alkaline phosphatase (ALP) activity were measured to analyze the effect of CM on the BMSCs. Experimental membranes were transplanted into a rat calvarial bone defect model. Microcomputed tomography and histologic analyses were performed 4 and 8 weeks after transplantation.
  
  
  RESULTS
  The CM derived from BMSCs can be immobilized on the PLGA membrane. Hydrophilic treatment of the PLGA membrane enhanced the amount of CM immobilization. LC/MS/MS analysis showed that the immobilized proteins on the surface of PLGA membrane were extracellular matrix, such as collagen, decorin, and fibronectin. The proteins in the CM, which were released from the PLGA membrane, enhanced cell proliferation and ALP activity in rat BMSCs. Newly formed bone area at the bone defects that had been treated with CM-HM was significantly high compared with those at bone defects treated with the other membranes.
  
  
  CONCLUSIONS
  The PLGA membrane treated with 0.5 mol/L NaOH and CM promoted bone regeneration in this rat calvarial defect model.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Tsuchiya
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohmori
authors.forename: Kenji
authors.initials: K
authors.lastname: Hara
authors.forename: Masahito
authors.initials: M
authors.lastname: Fujio
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ikeno
authors.forename: Hideharu
authors.initials: H
authors.lastname: Hibi
authors.forename: Minoru
authors.initials: M
authors.lastname: Ueda
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D001847:Bone Diseases / Q000473:pathology / Q000601:surgery; D001861:Bone Regeneration / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D002853:Chromatography, Liquid / Q000379:methods; D003094:Collagen / Q000032:analysis / Q000494:pharmacology; D017077:Culture Media, Conditioned / Q000737:chemistry*; D058575:Decorin / Q000032:analysis / Q000494:pharmacology; D005353:Fibronectins / Q000032:analysis / Q000494:pharmacology; D048091:Guided Tissue Regeneration / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D055767:Immobilized Proteins / Q000032:analysis / Q000494:pharmacology*; D019344:Lactic Acid / Q000737:chemistry*; D008297:Male; D008567:Membranes, Artificial; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D008855:Microscopy, Electron, Scanning; D010012:Osteogenesis / Q000187:drug effects; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D051381:Rats; D017207:Rats, Sprague-Dawley; D012886:Skull / Q000473:pathology / Q000601:surgery; D012972:Sodium Hydroxide / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods; D013997:Time Factors; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D017077:Culture Media, Conditioned; C546880:Dcn protein, rat; D058575:Decorin; D005353:Fibronectins; D055767:Immobilized Proteins; D008567:Membranes, Artificial; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D012972:Sodium Hydroxide; D003094:Collagen; D000469:Alkaline Phosphatase