Electrospun polymer nanofibers as substrate/carrier for engineering of human corneal epithelium

Abstract

PurposeElectrospun polymer nanofibers present a structure similar to extracellular matrix (ECM) and support the surrounding cells. The type of polymer used, as well as the polymer blending‐ratio, affects wettability. This in turn influences cell growth by altering the types of proteins adsorbed from the solution. Human corneal epithelial cells were grown on electrospun biodegradable and non‐biodegradable polymer membranes to evaluate the membranes’ potential within ocular surface tissue engineering.MethodsThe electrospun polymer membranes consisted of cellulose acetate, poly (lactic‐co‐glycolic acid) (PLGA), polycaprolactone (PCL), and blends of PCL and polyethylene glycol (PEG). Expression of CDH1 (E‐cadherin), ITGA6, ITGB4 (Integrin α6β4) and MKI67 (Ki67) genes were measured in all conditions after 14 days of culture using qRT‐PCR.ResultsCells seeded on all types of membranes expressed MKI67, which is associated with cell cycle activity and correlates with cell growth. MKI67 expression was high in cells grown on 3:2 blends of PCL and PEG (2.88) and PCL (2.75). This amount was 1.75, 1.00 and 1.59 for cells grown on cellulose acetate, 1:1 blend of PCL and PEG and PLGA respectively. The amount of ITGA6, ITGB4 expression was 1.72 in cells grown on PCL membranes, 1.10 for 3:2 blend of PCL and PEG, 1.05 for cellulose acetate, 1.53 for PLGA and 1.01 for 1:1 blend of PCL and PEG. Only cells grown on membranes containing blends of PCL: PEG showed CDH1 expression, which is critical for cell‐cell contact.ConclusionsAll polymer membranes enabled cellular adhesion and proliferation. PCL:PEG and PCL membranes appear to promote the highest proliferative activity and strongest cell‐membrane/cell‐cell adhesion. Thus, these might be the most promising substrates for epithelial ocular surface tissue engineering.