Here, we aimed to investigate osteogenic differentiation of human adipose-derived stem cells (hASCs) in three-dimensional (3D) bioprinted tissue constructs in vitro and in vivo. A 3D Bio-plotter dispensing system was used for building 3D constructs. Cell viability was determined using live/dead cell staining. After 7 and 14 days of culture, real-time quantitative polymerase chain reaction (PCR) was performed to analyze the expression of osteogenesis-related genes (RUNX2, OSX, and OCN). Western blotting for RUNX2 and immunofluorescent staining for OCN and RUNX2 were also performed. At 8 weeks after surgery, osteoids secreted by osteogenically differentiated cells were assessed by hematoxylin-eosin (H&E) staining,…
Hydrogels are particularly attractive as scaffolding materials for cartilage tissue engineering because their high water content closely mimics the native extracellular matrix (ECM). Hydrogels can also provide a three-dimensional (3D) microenvironment for homogeneously suspended cells that retains their rounded morphology and thus facilitates chondrogenesis in cartilage tissue engineering. However, fabricating hydrogel scaffolds or cell-laden hydrogel constructs with a predesigned external shape and internal structure that does not collapse remains challenging because of the low viscosity and high water content of hydrogel precursors. Here, we present a study on the fabrication of (cell-laden) alginate hydrogel constructs using a 3D bioplotting system…
The current strategies for the transplantation of meniscus should be strengthened to tackle the faced limitations of current methods in the clinics. One of the limitations is that current implants are not patient-specific. There is, therefore, a pressing need in the clinics to develop patient-specific implants. The aim of this study was to demonstrate a semi-automatic way of segmenting meniscus tissues from patients’ volumetric knee magnetic resonance imaging (MRI) datasets in order to obtain patient-specific 3D models for 3D printing of patient-specific constructs. High-quality MRI volumetric images were acquired from five healthy male human subjects. The advanced segmentation software, RheumaSCORE,…
Synchrotron radiation inline phase-contrast imaging combined with computed tomography (SR-inline-PCI-CT) offers great potential for non-invasive characterization and three-dimensional visualization of fine features in weakly absorbing materials and tissues. For cartilage tissue engineering, the biomaterials and any associated cartilage extracellular matrix (ECM) that is secreted over time are difficult to image using conventional absorption-based imaging techniques. For example, three-dimensional printed polycaprolactone (PCL)/alginate/cell hybrid constructs have low, but different, refractive indices and thicknesses. This paper presents a study on the optimization and utilization of inline-PCI-CT for visualizing the components of three-dimensional printed PCL/alginate/cell hybrid constructs for cartilage tissue engineering. First, histological analysis…
Infection or damage to the trachea, a thin walled and cartilage reinforced conduit that connects the pharynx and larynx to the lungs, leads to serious respiratory medical conditions which can often prove fatal. Current clinical strategies for complex tracheal reconstruction are of limited availability and efficacy, but tissue engineering and regenerative medicine approaches may provide viable alternatives. In this study, we have developed a new “hybrid graft” approach that utilizes decellularized tracheal tissue along with a resorbable polymer scaffold, and holds promise for potential clinical applications. First, we evaluated the effect of our decellularization process on the compression properties of…
To construct human adipose-derived mesenchymal stem cells (hASCs)-biomaterial mixture 3D bio-printing body and detect its osteogenesis in vivo, and to establish a guideline of osteogenesis in vivo by use of 3D bio-printing technology preliminarily.P4 hASCs were used as seed cells, whose osteogenic potential in vitro was tested by alkaline phosphatase (ALP) staining and alizarin red staining after 14 d of osteogenic induction. The cells were added into 20 g/L sodium alginate and 80 g/L gelatin mixture (cell density was 1×10(6)/mL), and the cell-sodium alginate-gelatin mixture was printed by Bioplotter 3D bio-printer (Envision company, Germany), in which the cells’survival rate was…
There is an urgent critical need for the development of clinically relevant tissue-engineered large bone substitutes that can promote early vascularization after transplantation. To promote rapid blood vessel growth in the engineered tissue, we preincubated aortic fragments, as well as, co-cultures of aortic fragments and osteoblast-like cells in matrigel-filled PLGA scaffolds before implantation into the dorsal skinfold chambers of balb/c mice. Despite an acceptable and low inflammatory response, preincubated aortic fragments accelerate early angiogenesis of tissue-engineered constructs; the angiogenesis was found to occur faster than that observed in previous studies. Thus, the time-period for achieving a denser microvascular network could…
Continuous composite fibres composed of polypyrrole (PPy) nanoparticles and reduced graphene oxide (rGO) at different mass ratios were fabricated using a single step wet-spinning approach. The electrical conductivity of the composite fibres increased significantly with the addition of rGO. The mechanical properties of the composite fibres also improved by the addition of rGO sheets compared to fibres containing only PPy. The ultimate tensile strength of the fibres increased with the proportion of rGO mass present. The elongation at break was greatest for the composite fibre containing equal mass ratios of PPy nanoparticles and rGO sheets. L929 fibroblasts seeded onto fibres…
A model sample consisting of two different hydroxyapatite (hAp) powders was used as a bone phantom to investigate the extent to which X-ray diffraction tomography could map differences in hAp lattice constants and crystallite size. The diffraction data were collected at beamline 1-ID, the Advanced Photon Source, using monochromatic 65 keV X-radiation, a 25 × 25 µm pinhole beam and translation/rotation data collection. The diffraction pattern was reconstructed for each volume element (voxel) in the sample, and Rietveld refinement was used to determine the hAp lattice constants. The crystallite size for each voxel was also determined from the 00.2 hAp…
The application of magnetic nanoparticles (MNPs) in tissue engineering (TE) approaches opens several new research possibilities in this field, enabling a new generation of multifunctional constructs for tissue regeneration. This study describes the development of sophisticated magnetic polymer scaffolds with aligned structural features aimed at applications in tendon tissue engineering (TTE). Tissue engineering magnetic scaffolds are prepared by incorporating iron oxide MNPs into a 3D structure of aligned SPCL (starch and polycaprolactone) fibers fabricated by rapid prototyping (RP) technology. The 3D architecture, composition, and magnetic properties are characterized. Furthermore, the effect of an externally applied magnetic field is investigated on…