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Three-dimensional printed polycaprolactone-based scaffolds provide an advantageous environment for osteogenic differentiation of human adipose-derived stem cells

The capacity of bone grafts to repair critical size defects can be greatly enhanced by the delivery of mesenchymal stem cells (MSCs). Adipose tissue is considered the most effective source of MSCs (ADSCs); however, the efficiency of bone regeneration using undifferentiated ADSCs is low. Therefore, this study proposes scaffolds based on polycaprolactone (PCL), which is widely considered a suitable MSC delivery system, were used as a three-dimensional (3D) culture environment promoting osteogenic differentiation of ADSCs. PCL scaffolds enriched with 5% tricalcium phosphate (TCP) were used. Human ADSCs were cultured in osteogenic medium both on the scaffolds and in 2D culture. Cell viability and osteogenic differentiation were tested at various time points for 42 days. The expression of RUNX2, collagen I, alkaline phosphatase, osteonectin and osteocalcin, measured by real-time polymerase chain reaction was significantly upregulated in 3D culture. Production of osteocalcin, a specific marker of terminally differentiated osteoblasts, was significantly higher in 3D cultures than in 2D cultures, as confirmed by western blot and immunostaining, and accompanied by earlier and enhanced mineralization. Subcutaneous implantation into immunodeficient mice was used for in vivo observations. Immunohistological and micro-computed tomography analysis revealed ADSC survival and activity toward extracellular production after 4 and 12 weeks, although heterotopic osteogenesis was not confirmed - probably resulting from insufficient availability of Ca/P ions. Additionally, TCP did not contribute to the upregulation of differentiation on the scaffolds in culture, and we postulate that the 3D architecture is a critical factor and provides a useful environment for prior-to-implantation osteogenic differentiation of ADSCs. Copyright © 2016 John Wiley & Sons, Ltd.

Future approaches of nanomedicine in clinical science

Burgeoning applications of nanotechnology are altering practices in traditional medicine. Promoted by the National Institutes of Health, nanomedicinal research is advancing technologies and revolutionizing strategies in clinical science by providing easy access to innovative nanodevices and nanosystems based on the rational design and precise integration of functional nanomaterials. Many long-standing challenges in clinical science could be met through advancement and revolutionization. Nanomedicinal diagnostics could acquire critical information regarding the status of diseased tissues and organs quickly and inexpensively with minimal sampling size and invasion. New strategies in therapeutic and regenerative nanomedicines will enable clinicians to take actions in a timely fashion and patient-friendly manner.