A polyhedral oligomeric silsesquioxane-based bilayered dermal scaffold seeded with adipose tissue-derived stem cells: in vitro assessment of biomechanical properties.
Chawla R., Tan A., Ahmed M., Crowley C., Moiemen NS., Cui Z., Butler PE., Seifalian AM.
BACKGROUND: Although commercial skin substitutes are widely available, its use remains challenging at surgery and postoperatively. The high cost is also prohibitive. We designed and characterized a scaffold for dermal replacement, using advanced nanocomposite materials, which are known to have unique nanoscale features that enhance cellular behavior. METHODS: A bilayered scaffold was developed using the nanocomposite, polyhedral oligomeric silsesquioxane, incorporated into poly(caprolactone-urea)urethane, resulting in a mechanically robust bioabsorbable polymer; forming the inner layer, which was designed with a range of porosities. The removable outer layer contained nanosilver. Tensile testing, surface tension, permeability, and scanning electron microscopy were performed. Optimal pore morphology for cellular proliferation was elucidated through adipose tissue-derived stem cell culture and a cell viability assay. All tests were repeated on Integra Dermal Regeneration Template. RESULTS: The physical construct was easy to handle and clinically applicable. Macroporosity and permeability of scaffolds was demonstrated, confirmed by scanning electron microscopy. Both tensile strength and surface tension were comparable with skin; outer layer demonstrated hydrophobicity and inner layer showed hydrophilicity. Cell assay confirmed cellular proliferation onto the scaffold, comparable with Integra. CONCLUSIONS: We demonstrate that a porous bilayered dermal scaffold could form the basis of a new generation of skin substitute that is both mechanically robust and harbors the ability for enhancing cell regeneration.