title: Modifying three-dimensional scaffolds from novel nanocomposite materials using dissolvable porogen particles for use in liver tissue engineering.
abstract: BACKGROUND
  Although hepatocytes have a remarkable regenerative power, the rapidity of acute liver failure makes liver transplantation the only definitive treatment. Attempts to incorporate engineered three-dimensional liver tissue in bioartificial liver devices or in implantable tissue constructs, to treat or bridge patients to self-recovery, were met with many challenges, amongst which is to find suitable polymeric matrices. We studied the feasibility of utilising nanocomposite polymers in three-dimensional scaffolds for hepatocytes.
  
  
  METHODS
  Hepatocytes (HepG2) were seeded on a flat sheet and in three-dimensional scaffolds made of a nanocomposite polymer (Polyhedral Oligomeric Silsesquioxane [POSS]-modified polycaprolactone urea urethane) alone as well as with porogen particles, i.e. glucose, sodium bicarbonate and sodium chloride. The scaffold architecture, cell attachment and morphology were studied with scanning electron microscopy, and we assessed cell viability and functionality.
  
  
  RESULTS
  Cell attachment to the scaffolds was demonstrated. The scaffold made with glucose particles as porogen showed a narrower range of pore size with higher porosity and better inter-pore communications and seemed to encourage near normal cell morphology. There was a steady increase of albumin secretion throughout the experiment while the control (monolayer cell culture) showed a steep decrease after day 7. At the end of the experiment, there was no significant difference in viability and functionality between the scaffolds and the control.
  
  
  CONCLUSIONS
  In this initial study, porogen particles were used to modify the scaffolds produced from the novel polymer. Although there was no significance against the control in functionality and viability, the demonstrable attachment on scanning electron microscopy suggest potential roles for this polymer and in particular for scaffolds made with glucose particles in liver tissue engineering.
authors.affiliation: University Department of Surgery, University College London, Royal Free Hospital, London, UK. h.adwan@ucl.ac.uk
authors.forename: Hussamuddin
authors.initials: H
authors.lastname: Adwan
authors.forename: Barry
authors.initials: B
authors.lastname: Fuller
authors.forename: Clare
authors.initials: C
authors.lastname: Seldon
authors.forename: Brian
authors.initials: B
authors.lastname: Davidson
authors.forename: Alexander
authors.initials: A
authors.lastname: Seifalian
mesh_terms: D002448:Cell Adhesion; D005947:Glucose / Q000737:chemistry; D056945:Hep G2 Cells; D006801:Humans; D008099:Liver / Q000166:cytology*; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D017646:Organosilicon Compounds / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*; D016062:Porosity; D017693:Sodium Bicarbonate / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D017646:Organosilicon Compounds; D011091:Polyesters; D011140:Polyurethanes; C521417:polyhedraloligosilsesquioxane; C016240:polycaprolactone; D012965:Sodium Chloride; D017693:Sodium Bicarbonate; C044690:polyetherurethane urea; D005947:Glucose