2008: Enhanced Mesenchymal Stem Cell Response on Biodegradable Poly(e-Caprolactone) Nanowires for Applications in Bone Tissue Engineering

Statement of Purpose: Critical sized defects in bone, whether caused by tumor resection, trauma, or implant surgery have presented insurmountable challenges to the current gold standard treatment for bone repair. Tissue engineered scaffolds offer promise in addressing these challenges and have been increasingly sophisticated and multifunctional since their inception about 15 years ago. The primary purpose of a tissue-engineered scaffold is to incite and promote the natural healing process of bone which typically does not occur in critical sized defects. Further, the scaffold must be biocompatible and biodegradable to allow native tissue integration, and the scaffold should mimic the micro/nano-hierarchical geometric structure of native bone. Several recent studies have shown enhanced bone cell response to controlled micro/nano-architecture 3 In addition to being biomimetic, a scaffold that is capable of eluting bioactive molecules (eg. BMPs, TGF-b, etc. to accelerate extracellular matrix production and tissue integration) or drugs (eg. antibiotics, cisplatin, etc. to prevent undesired biological response such as sepsis or cancer recurrence) in a controlled and sustained manner is highly desired. Various FDA approved polymers have been investigated for scaffold materials due to their tuneable mechanical properties, enhanced biocompatibility, and controllable biodegradability. In this work, we present a simple, solvent-free method for template synthesis of microaggregated nanowire surfaces from poly(ε-caprolactone) (PCL). Cell studies using a pre-osteoblast cell line indicates that these nanowire surfaces are cytocompatible and enhance cell functionality. Further, degradation and release rate studies indicate that these surfaces show promise for controlled drug delivery applications. More detailed studies are now directed towards using mesenchymal stems cells (MSCs) and characterizing the release of relevant bioactive molecules.