title: Decellularization of heart valve matrices: search for the ideal balance.
abstract: OBJECTIVE
  Currently used decellularization procedures have negative effects on extracellular matrix (ECM) integrity. The objective of this study is to evaluate four decellularization methods and their effect on the collagen ultrastructure, mechanical behavior and antigenicity of porcine aortic valves.
  
  
  METHODS
  Aortic valves were placed in a trypsin, osmotic, trypsin-osmotic or detergent-osmotic solution. Leaflets were processed for histology and mechanical testing. Matrices were implanted subdermally in rats to evaluate immune reaction and calcification.
  
  
  RESULTS
  Trypsin-osmotic methodology effected near-complete decellularization. Trypsin treatment resulted in cell removal only in the spongiosa layer. Osmotic and detergent-osmotic treatments did not remove any cells from the cusps. Mechanical strength was significantly inferior in the trypsin (p50,03) and trypsin-osmotic treated group (p50,04). Trypsin and trypsin-osmotic decellularized matrices evoked a strong CD31 inflammatory cell infiltration.
  
  
  CONCLUSIONS
  Enzymatic-osmotic decellularization appears to be the only effective method to remove cellular components. However, the near cell free scaffolds still evokes a strong CD31 T-cell inflammatory reaction.
authors.affiliation: Department of Basic Medical Sciences, Ghent University, Ghent, Belgium. pamela.somers@ugent.be
authors.forename: Pamela
authors.initials: P
authors.lastname: Somers
authors.forename: Filip
authors.initials: F
authors.lastname: De Somer
authors.forename: Maria
authors.initials: M
authors.lastname: Cornelissen
authors.forename: Hubert
authors.initials: H
authors.lastname: Thierens
authors.forename: Guido
authors.initials: G
authors.lastname: Van Nooten
mesh_terms: D000818:Animals; D001021:Aortic Valve / Q000166:cytology* / Q000276:immunology / Q000648:ultrastructure; D001696:Biomechanical Phenomena; D002114:Calcinosis / Q000209:etiology; D005109:Extracellular Matrix; D008422:Materials Testing; D051381:Rats; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*