Effect of Collagen Coating and Fiber Profile on Tenocyte Growth on Braided Poly-ε-Caprolactone Scaffolds for Tendon and Ligament Regeneration

Using scaffolds is a promising alternative to current methods of treatment for ruptures of tendons and ligaments. However, scaffolds are subject to a wide range of challenges, including mechanical, degradation, process-related and biological requirements. Poly-ε-caprolactone (PCL) fibers have already shown potential for tendon tissue engineering (TTE) because of their degradation kinetics and excellent mechanical properties. The objective of this study was to enhance the PCL scaffold for TTE, specifically in regard to the filament morphology and collagen coating. PCL fibers were melt-spun as monofilaments with circular and snowflake-shaped cross-sections. Different scaffold densities were achieved by applying three different braiding angles in the braiding process. Morphological characterization was conducted including porosity and pore size distribution using µ-CT. The scaffolds were collagenized and cellularized with primary tenocytes for 7 days. Immunofluorescence staining showed a certain alignment of cell growing direction with fiber direction. In cell viability and cell proliferation assays, significant improvements in cell response were observed for the snowflake fiber and collagen coating groups, especially when combined. The data suggest that the utilization of non-circular fibers may facilitate enhanced cell guidance and surface area, while the application of a collagen coating could optimize the cellular environment for adhesion and proliferation.