3D-Printed PCL Scaffolds Coated with Nanobioceramics Enhance Osteogenic Differentiation of Stem Cells

Abstract

With advances in bone tissue engineering, various materials and methods have been explored to find a better scaffold that can help in improving bone growth and regeneration. Three-dimensional (3D) printing by fused deposition modeling can produce customized scaffolds from biodegradable polyesters such as polycaprolactone (PCL). Although the fabricated PCL scaffolds exhibited a lack of bioactivity and poor cell attachment on their surfaces, herein, using a simple postfabrication modification method with hydroxyapatite (HA) and bioglasses (BGs), we obtained better cell proliferation and attachment. Biological behavior and osteosupportive capacity of the 3D-printed scaffolds including PCL, PCL/HA, PCL/BG, and PCL/HA/BG were evaluated in this study, while human adipose tissue-derived mesenchymal stem cells (hADSCs) were cultured on the scaffolds. The cell morphology, attachment, and proliferation were investigated using scanning electron microscopy (SEM), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, and 4′,6-diamidino-2-phenylindole (DAPI) staining. In the next step, the ability of stem cells to differentiate into osteoblasts was evaluated by measuring alkaline phosphatase (ALP) activity, calcium deposition, and bone-related gene and protein expression. In the end, the expression levels of miR-20a, miR-125a, and their target genes were also investigated as positive and negative regulators in osteogenesis pathways. The results showed that the coated scaffolds with bioceramics present a more appropriate surface for cell adhesion and proliferation, as well as efficient potential in inducing osteoconduction and osteointegration compared to PCL alone and control. The PCL/HA/BG scaffold exhibited higher in vitro cell viability and bone formation compared to the other groups, which can be due to the synergistic effect of HA and BG. On the whole, this tricomponent 3D-printing scaffold has a promising prospect for bone tissue engineering applications.

3D printed poly(lactic acid)-based nanocomposite scaffolds with bioactive coatings for tissue engineering applications

“…These observations are a result of the intrinsic property of SrBG to induce apatite formation and favor cell differentiation and of HA to promote osteogenesis, in combination with increased surface roughness which is known to affect osteogenesis in several osteoblast-like cell models [87]. PCL scaffolds coated with bioglass and HA could improve the osteogenic differentiation of stem cells as well [88]. PLA scaffolds with 20 wt.%HA had an increased osteogenic potential and showed increased mineralization, due to the release of Ca and P ions from HA [89].…”

Special Features of Polyester-Based Materials for Medical Applications

“…The usual techniques for preparing modified polyesters for artificial bone-substitute materials involve 3D printing [ 51 , 61 , 65 , 66 , 72 , 74 , 75 , 76 ], thermally induced phase separation (TIPS) [ 32 ], salt leaching [ 32 , 69 , 79 ], solvent casting [ 33 , 35 , 77 , 79 ], electrospinning [ 60 , 64 , 70 ], copolymerization [ 31 ], and polycondensation [ 73 ].…”

“…Innovative scaffolds with a three-dimensional (3D) architecture were obtained by 3D melt extruding of PCL with 20 wt % chitosan [ 66 ] and coating of 3D-printed PCL scaffolds with HA and BG [ 72 ].…”

Strategies To Modify the Surface and Bulk Properties of 3D-Printed Solid Scaffolds for Tissue Engineering Applications

“…Hence, they find immense utility in bone tissue engineering as a surface-modifying agent. In the study by Fazeli et al, hydroxyapatite and bioglass were deposited on the surface of a 3D-printed polycaprolactone (PCL) scaffold, and they observed enhanced osteogenic differentiation of stem cells under in vitro conditions . Carbon fiber-reinforced polyether ether ketone (PEEK) is observed to have better mechanical strength than pristine PEEK but retains biocompatibility and high cell density on the scaffold under in vitro conditions .…”

“…In the study by Fazeli et al, hydroxyapatite and bioglass were deposited on the surface of a 3D-printed polycaprolactone (PCL) scaffold, and they observed enhanced osteogenic differentiation of stem cells under in vitro conditions. 13 Carbon fiber-reinforced polyether ether ketone (PEEK) is observed to have better mechanical strength than pristine PEEK but retains biocompatibility and high cell density on the scaffold under in vitro conditions. 14 These nanocomposites, where nanoparticles and nanofibers are blended with the base polymers, are being considered to develop scaffolds/devices with improved surface properties for tissue engineering applications.…”