The phenotypic response of bovine corneal endothelial cells on chitosan/polycaprolactone blends

Abstract

Although various behaviors of corneal endothelial cells (CECs) have been investigated, the interaction of CECs with different biodegradable biomaterials has not been systematically well explored. Thus, two common biodegradable biomaterials with dissimilar characteristics, chitosan and polycaprolactone (PCL), were examined in bovine CEC (BCEC) culture systems to elucidate their possible impact on clinical demand and scientific interest. The interaction between cells and matrices was also surveyed. Pure PCL could not be used for observation because of its opacity. Nevertheless, BCECs did not adhere and proliferate well on chitosan. To overcome this drawback, we developed blends using various proportions of chitosan and PCL: PCL 25, PCL 50, and PCL 75. As the content of PCL increased in the blends, BCECs showed greater degrees of adhesion and proliferation. Furthermore, cells reached confluence and maintained their typical hexagonal shape at day 7 on blends PCL 50 and PCL 75. In addition, when BCECs were cultured on the blends, the expressions of the differentiation marker N-cadherin and tight junction marker ZO-1 were well developed, resembling the physiological phenotypes. A possible explanation for the increased proliferation and preservation of BCECs on the blends is that blending chitosan and PCL could create a bioactive substratum. This method could regulate gene expression to synthesize more extracellular matrix type IV collagen, paving an important way to provide a favorable environment for BCEC cultures. Accordingly, promoting CEC growth effects by blending may be applied to the tissue engineering of corneal endothelium.