Target gene delivery is crucial to gene therapy. Adeno-associated virus (AAV) has emerged as a primary gene therapy vector due to its broad host range, long-term expression, and low pathogenicity. However, AAV vectors have some limitations, such as immunogenicity and insufficient targeting.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
April 2021
Three-dimensional (3D) printing is a promising method to prepare scaffolds for tissue regeneration. Collagen and chitosan composites are superior materials for tissue engineering scaffold but rarely printed due to their poor printability. Here, we prepared a series of tunable hybrid collagen/chitosan bioinks with significantly improved printability through hydrogen bond interaction and printed them into scaffolds by carefully controlling the temperature.
View Article and Find Full Text PDFVascularization is essential for the regeneration of three-dimensional (3D) bioprinting organs. As a general method to produce microfluidic channels in 3D printing constructs, coaxial extrusion has attracted great attention. However, the biocompatible bioinks are very limited for coaxial extrusion to fabricate microchannels with regular structure and enough mechanical properties.
View Article and Find Full Text PDFSheng Wu Yi Xue Gong Cheng Xue Za Zhi
February 2020
Tricalcium phosphate (TCP) is one of the most widely used bioceramics for constructing bone tissue engineering scaffold. The three-dimensional (3D) printed TCP scaffold has precise and controllable pore structure, while with the limitation of insufficient mechanical properties. In this study, we investigated the effect of sintering temperature on the mechanical properties of 3D-printed TCP scaffolds in detail, due to the important role of the sintering process on the mechanical properties of bioceramic scaffolds.
View Article and Find Full Text PDFMesenchymal stem cells (MSCs) are progenitors of chondrocytes and could be used as a potential therapy for cartilage defects in diarthrodial joints. However, promoting chondrogenic differentiation of MSCs remains a daunting challenge. As a small molecular drug, dasatinib can promote MSC differentiation, although the exact mechanisms of chondrogenic differentiation are unclear.
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
April 2020
Glucosamine (GlcN) has been widely used to reduce joint pain and osteoarthritis progression, but the efficacy of GlcN remains controversial because of the low GlcN concentration reaching the articular cavity. The aim of this study is to provide an effective approach of GlcN delivery to a target site using photocrosslinkable methacrylated gelatin (GelMA)-based hydrogels, where GlcN could be gradually released during the degradation of the GelMA hydrogel. Herein, GlcN was acrylated as the acryloyl glucosamine (AGA) and covalently grafted to GelMA, and more than 87.
View Article and Find Full Text PDFGelatin and chitosan (CS) are widely used natural biomaterials for tissue engineering scaffolds, but the poor mechanical properties of pure gelatin or CS hydrogels become a big obstacle that limits their use as scaffolds, especially in load-bearing tissues. This study provided a novel mechanism of forming interpenetrating network (IPN) of gelatin methacryloyl (GelMA) and CS hydrogels by covalent bonds and hydrophobic interactions through photocrosslinking and basification, respectively. By characterization of the compressive and tensile moduli, ultimate tensile stress and strain, it was found that semi-IPN and IPN structure can greatly enhance the mechanical properties of GelMA-CS hydrogels compared to the single network CS or GelMA.
View Article and Find Full Text PDFMethacrylated gelatin (GelMA) has been widely used as a tissue-engineered scaffold material, but only low-concentration GelMA hydrogels were found to be promising cell-laden bioinks with excellent cell viability. In this work, we reported a strategy for precise deposition of 5% (w/v) cell-laden GelMA bioinks into controlled microarchitectures with high cell viability using extrusion-based three-dimensional (3D) bioprinting. By adding gelatin into GelMA bioinks, a two-step cross-linking combining the rapid and reversible thermo-cross-linking of gelatin with irreversible photo-cross-linking of GelMA was achieved.
View Article and Find Full Text PDFA simple, accurate and validated reverse-phase high-performance liquid chromatography (HPLC)/UV method is developed for the determination of glucosamine hydrochloride (GlcN), N-acetyl-glucosamine (NAG) and N-acryloyl-glucosamine (AGA) released from photocrosslinked gelatin hydrogels. The HPLC separation was achieved on a Shimadzu InertSustain amino column (250 × 4.6 mm, 5 µm particle size) at room temperature using a mobile phase of acetonitrile-phosphate buffer (75:25, v/v, pH 6.
View Article and Find Full Text PDFJ Biomater Appl
February 2015
The use of hydrogel-based cell transport scaffolds holds great promise in regenerative medicine, such as treating osteoarthritis. Gelatin and glucosamine are the ideal materials to be used in the hydrogel scaffolds for cartilage regeneration for they could act as compositions of cartilage. To overcome the weak strength of traditional gelatin hydrogels and down-regulate cell toxicity of glucosamine, gelatin and glucosamine molecules were grafted with acrylate groups and covalently crosslinked under photo-radiation to form hydrogels.
View Article and Find Full Text PDFHere we developed a composite scaffold of pearl/poly(lactic-co-glycolic acid) (pearl/PLGA) utilizing the low-temperature deposition manufacturing (LDM). LDM makes it possible to fabricate scaffolds with designed microstructure and macrostructure, while keeping the bioactivity of biomaterials by working at a low temperature. Process optimization was carried out to fabricate a mixture of pearl powder, PLGA and 1,4-dioxane with the designed hierarchical structures, and freeze-dried at a temperature of -40 degrees C.
View Article and Find Full Text PDF