![]() ![]() After the cells adhered to the flasks, the medium was removed and replaced by a new 8 ml medium. First, 5000 cells were seeded on a 75 cm 2 culture flask with 8 ml medium. The cells were cultured in an alpha-minimum essential medium (α-MEM) supplemented with 5% fetal bovine serum, 2 mmol/L glutamine, and 100 μg/ml penicillin–streptomycin and incubated at 37☌ in a humidified atmosphere with 5% CO 2. Preosteoblasts (MC3T3-E1, Osteoblast cell line) were bought from the Chinese Academy of Medical Sciences. All scaffolds were molded at 3 mm height and 5 mm diameter, which fit the wells of the 96-well microplate (3559, 96WL, Corning, USA). The structure of the clear scaffold and scaffolds with gelatin and platelets was imaged as shown in Figure 1 via scanning electron microscopy. The 3D printed scaffold with completely interconnected pores was prepared according to our design. The treated groups were prepared by adding 20 µl of PRP to the scaffolds with gelatin then freeze-dried. The sterilization process was treatment with ethylene oxide, and the scaffolds were prepared with gelatin. The NaCl was absterged using distilled water, and then freeze-dried for the second time. The mixed solid was treated at 180☌ for thermo-crosslinking. To prepare the scaffold with gelatin, 1 g NaCl was added to 5 ml of gelatin solution (5%), and then the solution was perfused into a 3D printed scaffold and lyophilized well. Three groups of scaffolds were prepared including clear scaffolds (blank group), scaffolds with gelatin (control group), and scaffolds with gelatin and platelets (treated group). The 3D porous titanium was printed based on laser sintering technology (Concept Laser Mlab, Germany) in two sizes: 5 mm diameter and 3 mm thickness for cultivating cells in 96-well plate and 8 mm diameter and 3 mm thickness for implanting in vivo, respectively. The titanium skeletons that formed the internal porous structure and the external appearance of scaffolds were 100 µm in diameter. The internal pores were orderly arranged regular dodecahedrons within the scaffolds with ϕ = 1500 µm. The scaffolds possess an internal porous structure designed in a computer aided design environment using the software Rhino 5.0 (Robert McNeel & Associates, USA). We also measured the cytotoxicity of the scaffold using CCK-8 assay. Some of the PDGFs that were measured include TGF-β1 and vascular endothelial growth factor (VEGF), which play significant roles in wound healing and tissue regeneration. In this study, we designed a 3D printed scaffold with gelatin and platelets, examined the proliferation of preosteoblasts in the scaffolds using a cell counting kit-8 (CCK-8) assay and the growth factor release at various time points. Many platelet-derived factors play important roles in cell proliferation and differentiation including platelet-derived growth factor (PDGF), transforming growth factor (TGF)-β1, and insulin-like growth factors-1. Platelets represent a type of specific source of growth factors and cytokines that are involved in wound healing and tissue repair. With the recent rapid development of 3D printing technology, not only can we print 3D scaffolds with controllable inner microstructures but also we can have scaffolds composed with components in the extracellular matrix to deliver biomaterials. Scaffold microstructures are able to regulate cell behaviors such as proliferation, differentiation, and apoptosis. The development of three-dimensional (3D) printing technology has dramatically changed scaffold designs in regenerative medicine. These methods can make scaffolds with higher porosity, but their size, shape, and interconnectivity are not easy to control, which may limit the prognosis in many aspects thus, getting satisfactory outcomes when treating bone defects using bone scaffolds is still very challenging. The traditional methods of manufacturing scaffolds mainly focus on reshaping the structure of specific types of materials and give the scaffold some biomedical properties via processes such as leaching or soaking. Bone scaffolds, which provide the benefit of avoiding unwanted immunological responses and eliminate the risk of acquiring infectious diseases from autografts and allografts, are widely used by orthopedic surgeons when repairing different types of bone defects. The methodology of repairing osteochondral defects is a critical issue in orthopedic surgery. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |