Perfused culture of gingival fibroblasts in a degradable/polar/hydrophobic/ionic polyurethane (D-PHI) scaffold leads to enhanced proliferation and metabolic activity

Periodontal diseases cause the breakdown of the tooth-supporting gingival tissue. In treatments aimed at gingival tissue regeneration, tissue engineering is preferred over the common treatments such as scaling. Perfused (dynamic) culture has been shown to increase cell growth in tissue-engineered scaffolds. Since gingival tissues are highly vascularized, it was desired to investigate the influence of perfusion on the function of human gingival fibroblasts (HGF) when cultured in a degradable/polar/hydrophobic/ionic polyurethane scaffold during the early culture phase (4 weeks) of engineering gingival tissues. It was observed that the growth of HGF was continuous over 28 days in dynamic culture (3-fold increase, p < 0.05), while it was reduced after 14 days in static culture (i.e. no flow condition). Cell metabolic activity, as measured by a WST-1 assay, and total protein production show that HGF were in different metabolic states in the dynamic vs. static cultures. Observations from scanning electron microscopy and type I collagen (Col I) production measured by Western blotting suggest that medium perfusion significantly promoted collagen production in HGF after the first 4 weeks of culture (p < 0.05). The different proliferative and metabolic states for HGF in the perfused scaffolds suggest a different cell phenotype which may favour tissue regeneration.