Stem cells combined 3D electrospun nanofibrous and macrochannelled matrices: a preliminary approach in repair of rat cranial bones

Toxicological Assessment of Biodegradable Poli-ε-Caprolactone Polymer Composite Materials Containing Hydroxyapatite, Bioglass, and Chitosan as Potential Biomaterials for Bone Regeneration Scaffolds

Polycaprolactone (PCL) is a biodegradable polyester that might be used in tissue engineering to obtain scaffolds for bone reconstruction using 3D-printing technologies. New material compositions based on PCL, with improved physicochemical properties and excellent biocompatibility, would improve its applicability in bone regeneration. The aim of this study was to assess the potential toxic effects of PCL-based composite materials containing 5% hydroxyapatite (PCL/SHAP), 5% bioglass (PCL/BIO), or 5% chitosan (PCL/CH) on MG-63 human fibroblast-like cells in vitro. Material tests were carried out using X-ray diffraction, differential thermal analysis/thermal gravimetry, BET specific surface analysis, and scanning electron microscopy. The effect of the biomaterials on the MG-63 cells was then assessed based on toxicity tests using indirect and direct contact methods. The analysis showed that the tested biomaterials did not significantly affect cell morphology, viability, proliferation, or migration. We concluded that biodegradable PCL-based scaffolds may be suitable for tissue scaffold production, and the addition of bioglass improves the growth of cultured cells.

Surgical method for critical sized cranial defects in rat cranium

Cranial tissue models are a widely used model to show the bone repair and the regeneration ability of candidate biomaterials for tissue engineering purposes. Until now, efficacy studies of different biomaterials for calvarial defect bone regeneration have been reported, generally in small animal models. This paper offers a versatile, reliable, and reproducible surgical method for creating a critical-sized cranial defect in rats including critical steps and tried-and-tested tips. The method proposed here,•Shows a general procedure for in vivo cranial models.•Provide an insight to restore bone tissue repair that may be used in combination with several tissue engineering strategies•Is a crucial technique that may guide in vivo bone tissue engineering.

Osteon-mimetic 3D nanofibrous scaffold enhances stem cell proliferation and osteogenic differentiation for bone regeneration

The scaffold microstructure is important for bone tissue engineering. Failure to synergistically imitate the hierarchical microstructure of the components of bone, such as an osteon with concentric multilayers assembled by nanofibers, hinders the performance for guiding bone regeneration. Here, a 2D bilayer nanofibrous membrane (BLM) containing poly(lactide-co-glycolide) (PLGA)/polycaprolactone (PCL) composite membranes in similar compositions (PCL15 and PCL20), but possessing different degrees of shrinkage, was fabricated via sequential electrospinning. Upon incubation in phosphate buffered saline (PBS) (37 °C), the 2D BLM spontaneously deformed into a 3D shape induced by PCL crystallization within the PLGA matrix, and the PCL15 and PCL20 layer formed a concave and convex surface, respectively. The 3D structure contained curved multilayers with an average diameter of 776 ± 169 μm, and on the concave and convex surface the nanofiber diameters were 792 ± 225 and 881 ± 259 nm, respectively. The initial 2D structure facilitated the even distribution of seeded cells. Adipose-derived stem cells from rats (rADSCs) proliferated faster on a concave surface than on a convex surface. For the 3D BLM, the osteogenic differentiation of rADSCs was significantly higher than that on 2D surfaces, even without osteogenic supplements, which resulted from the stretched cell morphology on the curved sublayer leading to increased expression of lamin-A. After being implanted into cranial defects in Sprague Dawley (SD) rats, 3D BLM significantly accelerated bone formation. In summary, 3D BLM with an osteon-like structure provides a potential strategy to repair bone defects.

Recent advances in polymer scaffolds for biomedical applications

The review provides insights into current advancements in electrospinning-assisted manufacturing for optimally designing biomedical devices for their prospective applications in tissue engineering, wound healing, drug delivery, sensing, and enzyme immobilization, and others. Further, the evolution of electrospinning-based hybrid biomedical devices using a combined approach of 3 D printing and/or film casting/molding, to design dimensionally stable membranes/micro-nanofibrous assemblies/patches/porous surfaces, etc. is reported. The influence of various electrospinning parameters, polymeric material, testing environment, and other allied factors on the morphological and physico-mechanical properties of electrospun (nano-/micro-fibrous) mats (EMs) and fibrous assemblies have been compiled and critically discussed. The spectrum of operational research and statistical approaches that are now being adopted for efficient optimization of electrospinning process parameters so as to obtain the desired response (physical and structural attributes) has prospectively been looked into. Further, the present review summarizes some current limitations and future perspectives for modeling architecturally novel hybrid 3 D/selectively textured structural assemblies, such as biocompatible, non-toxic, and bioresorbable mats/scaffolds/membranes/patches with apt mechanical stability, as biological substrates for various regenerative and non-regenerative therapeutic devices.

Soya protein isolate-polyethylene oxide electrospun nanofiber membrane with bone marrow-derived mesenchymal stem cell for enhanced bone regeneration

In this study, we prepared an electrospun nanofiber membrane from soya protein isolate (SPI) and polyethylene oxide (PEO) loaded with rat bone marrow-derived mesenchymal stem cells (rBMSC), as a cell-scaffold approach to enhance bone regeneration. Different ratios of SPI:PEO (7:0, 7:1, 7:3, 7:5, and 0:7) was investigated to obtain uniform nanofibers, and crosslinked with EDC/NHS to stabilize the membranes. SPI/PEO membrane (7:3) was found to create more uniform and stable nanofibers at a flow rate of 9 µL/min, spun in a cylindrical collector rotating at 350 r/min, 23 kV DC voltage, and needle tip to collector distance of 13 cm. The loaded rBMSC were pre-differentiated to ensure commitment towards osteoblastic lineage. The SPI/PEO electrospun nanofiber membranes were successful in allowing for cell attachment and growth of the rBMSC and was further investigated in vivo using a rat skull defect model. New bone formation was observed for the optimized SPI/PEO electrospun nanofiber membrane (7:3) with and without rBMSC, but with faster new bone formation for SPI/PEO electrospun nanofiber membrane loaded with rBMSC as compared to SPI/PEO electrospun nanofiber membrane only and control (defect only).