Thymosin ß4 coated nanofiber scaffolds for the repair of damaged cardiac tissue.

After a cardiac event, proper treatment and care of the damaged tissue is crucial in restoring optimal cardiac function and preventing future cardiac events. Recently, thymosin ß4 has been found to play a vital role in cardiac cell health and development by regulating angiogenesis, inflammatory responses, and wound healing. We proposed that defined poly(ϵ-caprolactone) (PCL) nanoscaffolds coated with thymosin ß4 could efficiently differentiate murine-derived cardiomyocytes into functioning cardiac tissue. PCL nanoscaffolds were developed through electrospinning technology, and subsequently coated with a thymosin ß4 solution. Cardiomyocytes were seeded on coated and uncoated nanoscaffolds and observed for six days via fluorescent and electron microscopy. Our results demonstrated a robust growth and differentiation of cardiomyocytes on coated nanoscaffolds compared with uncoated, showing potential for nanoscaffold-mediated cardiac cell replacement in vivo after an MI or other cardiac event.

Novel nanocomposite biomaterial to differentiate bone marrow mesenchymal stem cells to the osteogenic lineage for bone restoration.

BACKGROUND/OBJECTIVE: As the bone engineering field moves away from nonviable implants to more biocompatible and natural structures, nanomedicine has emerged as a superior tool for developing implantable materials. METHODS: Here, we describe the fabrication and testing of a nanocomposite structure composed of chitosan and a biocompatible thermoplastic (PMMA). RESULTS: Our nanocomposite material displayed morphologically similar characteristics to an extracted murine femur during microscopic and spectroscopic analysis as seen through SEM and FTIR. Crosslinking our nanocomposite enhanced structural and strength characteristics significantly above the noncrosslinked sample, mimicking the strength of an extracted mammalian bone. When cocultured with bone marrow mesenchymal stem cells, the composite material proved to be osteoinductive and osteogenic via DAPI and actin staining, differentiating BMSCs into the osteogenic lineage and promoting mineral deposition. Nodule formation, indicative of mineralization during BMSC differentiation, was confirmed spectroscopically via FTIR and autofluorescence of the nodule. CONCLUSION: These encouraging results show promise for in vivo implantation of our novel scaffold that is both biocompatible and biomimetic in strength and composition.