Three dimensional electrospun PCL/PLA blend nanofibrous scaffolds with significantly improved stem cells osteogenic differentiation and cranial bone formation

Abstract

Nanofibrous scaffolds that are morphologically/structurally similar to natural ECM are highly interested for tissue engineering; however, the electrospinning technique has the difficulty in directly producing clinically relevant 3D nanofibrous scaffolds with desired structural properties. To address this challenge, we have developed an innovative technique of thermally induced nanofiber self-agglomeration (TISA) recently. The aim of this work was to prepare (via the TISA technique) and evaluate 3D electrospun PCL/PLA blend (mass ratio: 4/1) nanofibrous scaffolds having high porosity of ~95.8% as well as interconnected and hierarchically structured pores with sizes from sub-micrometers to ~300 µm for bone tissue engineering. The hypothesis was that the incorporation of PLA (with higher mechanical stiffness/modulus and bioactivity) into PCL nanofibers would significantly improve human mesenchymal stem cells (hMSCs) osteogenic differentiation in vitro and bone formation in vivo. Compared to neat PCL-3D scaffolds, PCL/PLA-3D blend scaffolds had higher mechanical properties and in vitro bioactivity; as a result, they not only enhanced the cell viability of hMSCs but also promoted the osteogenic differentiation. Furthermore, our in vivo studies revealed that PCL/PLA-3D scaffolds considerably facilitated new bone formation in a critical-sized cranial bone defect mouse model. In summary, both in vitro and in vivo results indicated that novel 3D electrospun PCL/PLA blend nanofibrous scaffolds would be strongly favorable/desired for hMSCs osteogenic differentiation and cranial bone formation.

Mechanically cartilage-mimicking poly(PCL-PTHF urethane)/collagen nanofibers induce chondrogenesis by blocking NF–kappa B signaling pathway

“…Compared to other tissue engineering scaffolds, electrospun nanofibers exhibit several advantages, such as high surface area and high porosity. By adjusting the solution parameters and spinning conditions, electrospinning can easily control the fiber properties, including the diameter, structure, surface and mechanical properties of the fibers for constructing scaffolds to facilitate the differentiation of stem cells into different types of cells including osteoblasts [17], neuronal cells [18], chondrocytes [19], and cardiomyocytes [20]. PCL can be easily synthesized with polytetrahydrofuran (PTHF) to form PCL-PTHF copolymers [21].…”

Polycaprolactone nanofiber scaffold enhances the osteogenic differentiation potency of various human tissue-derived mesenchymal stem cells

“…Notably, the use of polycaprolactone (PCL) for tissue engineering increased significantly over the past decade [12–14]. PCL, a biodegradable polyester material, has been widely exploited in several kinds of implants, adhesion barriers, and drug delivery devices.…”

Optimization and integration of nanosilver on polycaprolactone nanofibrous mesh for bacterial inhibition and wound healing in vitro and in vivo

“…22,23 Polycaprolactone (PCL) is a biocompatible and biodegradable material approved by the US Food and Drug Administration (FDA). 24,25 The electrospun PCL nanofibrous mesh possesses high porosity and good mechanical strength, which are important factors for wound dressings. 22,26,27 Moreover, the high specific surface area and interwoven nanofibers endow PCL nanofibrous mesh enough space for antibacterial agents residing.…”