Evaluation of chondrogenesis within PEGT: PBT scaffolds with high PEG content

Porous poly(ethylene glycol) terephthalate:poly (butylene terephthalate) (PEGT:PBT) scaffolds with high PEG molecular weight (1000 g/mole) and PEGT content (60%) were fabricated using two different processes-paraffin templating and compression molding-for cartilage engineering applications. This polymer composition has previously been shown to enable chondrocyte adhesion and maintain differentiated phenotype in 2D monolayer culture. The influence of 3D polymer scaffold processing on the formation of cartilaginous tissue was studied by seeding primary immature bovine chondrocytes within cylindrical scaffolds in mixed flask reactors for 3 days, followed by cultivation in culture plates for a total of 10 or 24 days. Tissue-polymer constructs were evaluated morphologically by SEM and histology, and quantitatively for cellularity, total collagen, and glycosaminoglycan content, all of which remained statistically equivalent for each time point tested, irrespective of fabrication method. These data demonstrate that the polymers engineered for this study were able to support chondrogenesis independent of scaffold fabrication process, with the influence of pore architecture lessened by the highly hydrated scaffold microenvironments induced by high PEG content.