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BACKGROUND: As seed cells, human umbilical cord mesenchymal stem cells have many advantages, such as a broad array of sources, easy access, low immunogenicity, osteogenic differentiation potential, high proliferation and self-renewal ability. In recent years, there are more and more reports about their application for bone tissue engineering. OBJECTIVE: To summarize isolation, culture, osteogenic induction and scaffolds. METHODS: The first author searched CNKI and PubMed databases with key words of “human umbilical cord mesenchymal stem cells, isolation, culture, osteogenic differentiation, scaffold, bone tissue engineering” in both Chinese and English, so as to review the relevant literature from 2004 to 2020. Finally, 104 articles were included. RESULTS AND CONCLUSION: There are different methods of isolation and culture of umbilical cord mesenchymal stem cells. Serum-free or animal serum substitute culture system and co-culture technique have made great progress, and three-dimensional culture system will be the development direction in the future. The exact mechanisms of osteogenic differentiation of umbilical cord mesenchymal stem cells are unclear, which need further elucidation. To date, it is still the focus of researchers to develop composite scaffolds with better properties. Bio-printing technology has primarily solve the difficult problem of controlling precisely the complex inner structure of the scaffolds at the micron scale and fabricating individual scaffolds, bringing great hope for bone tissue engineering. The design and fabrication of scaffolds with multiple ideal compositions (including biocompatibility, high porosity at the micro and macro level, mechanical properties, related absorption and so on) and the less clinical side effects remain one of the key challenges in bone tissue engineering.
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BACKGROUND: Repair materials for bone tissue engineering should hold good biocompatibility and degradability. There are various related studies, but the Chinese medicine composite cellular bioscaffolds are little reported. OBJECTIVE: To detect the in vitro cytotoxicity of rabbit bone marrow mesenchymal stem cells-cuttlebone bioscaffold based on the Biological Evaluation of Medical Device, and assess its cytotoxicity level in order to provide the theoretical support for its clinical application. METHODS: Bone marrow mesenchymal stem cells-cuttlebone bioscaffold extract was prepared according to an ISO standard — material area: extraction medium volume = 3-6 cm2:1 mL. L-929 cell suspension was prepared, and the cells were then cultured with a density of 1×107/L. There were three groups: positive group (DMEM medium containing phenol), experimental group (material extract), and negative group (DMEM culture medium). The absorbance value of L-929 cells was detected by MTT assay after 24, 48 and 72 hours of culture. The relative proliferation rate of cells was then calculated and the toxicity level was valued in each group. RESULTS AND CONCLUSION: The absorbance values in the experimental, negative and positive groups were not exactly same at different time points (P=0.000 < 0.01). The absorbance values in the experimental and negative groups were significantly higher than those in the positive group (P < 0.01).The cytotoxicity of bone marrow mesenchymal stem cells-cuttlebone bioscaffold was grade 1. To conclude, the bone marrow mesenchymal stem cells-cuttlebone bioscaffold has no obvious toxic effects, and meets the requirements of biomaterial application.
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BACKGROUND: Mesenchymal stem cells (MSCs) and/or biological scaffolds have been used to regenerate articular cartilage with variable success. In the present study we evaluated cartilage regeneration using a combination of bone marrow (BM)-MSCs, Hyalofast™ and/or native cartilage tissue following full thickness surgical cartilage defect in rabbits. METHODS: Full-thickness surgical ablation of the medial-tibial cartilage was performed in New Zealand white (NZW) rabbits. Control rabbits (Group-I) received no treatment; Animals in other groups were treated as follows. Group-II: BMMSCs (1 × 10⁶ cells) + Hyalofast™; Group-III: BMMSCs (1 × 10⁶ cells) + cartilage pellet (CP); and Group-IV: BMMSCs (1 × 10⁶ cells) + Hyalofast™+ CP. Animals were sacrificed at 12 weeks and cartilage regeneration analyzed using histopathology, International Cartilage Repair Society (ICRS-II) score, magnetic resonance observation of cartilage repair tissue (MOCART) score and biomechanical studies. RESULTS: Gross images showed good tissue repair (Groups IV>III>Group II) and histology demonstrated intact superficial layer, normal chondrocyte arrangement, tidemark and cartilage matrix staining (Groups III and IV) compared to the untreated control (Group I) respectively. ICRS-II score was 52.5, 65.0, 66 and 75% (Groups I–IV) and the MOCART score was 50.0, 73.75 and 76.25 (Groups II–IV) respectively. Biomechanical properties of the regenerated cartilage tissue in Group IV closed resembled that of a normal cartilage. CONCLUSION: Hyalofast™ together with BM-MSCs and CP led to efficient cartilage regeneration following full thickness surgical ablation of tibial articular cartilage in vivo in rabbits. Presence of hyaluronic acid in the scaffold and native microenvironment cues probably facilitated differentiation and integration of BM-MSCs.
Subject(s)
Animals , Rabbits , Bone Marrow , Cartilage , Cartilage, Articular , Chondrocytes , Cues , Hyaluronic Acid , Mesenchymal Stem Cells , New Zealand , Osteoarthritis , RegenerationABSTRACT
Spinal cord injury (SCI), especially the complete SCI, usually results in complete paralysis below the level of the injury and seriously affects the patient's quality of life. SCI repair is still a worldwide medical problem. In the last twenty years, Professor DAI Jianwu and his team pioneered complete SCI model by removing spinal tissue with varied lengths in rodents, canine, and non-human primates to verify therapeutic effect of different repair strategies. Moreover, they also started the first clinical study of functional collagen scaffold on patients with acute complete SCI on January 16th, 2015. This review mainly focusses on the possible mechanisms responsible for complete SCI. In common, recovery of some sensory and motor functions post complete SCI include the following three contributing reasons. ① Regeneration of long ascending and descending axons throughout the lesion site to re-connect the original targets; ② New neural circuits formed in the lesion site by newly generated neurons post injury, which effectively re-connect the transected stumps; ③ The combined effect of ① and ②. The numerous studies have confirmed that neural circuits rebuilt across the injury site by newborn neurons might be the main mechanisms for functional recovery of animals from rodents to dogs. In many SCI model, especially the complete spinal cord transection model, many studies have convincingly demonstrated that the quantity and length of regenerated long descending axons, particularly like CST fibers, are too few to across the lesion site that is millimeters in length to realize motor functional recovery. Hence, it is more feasible in guiding neuronal relays formation by bio-scaffolds implantation than directing long motor axons regeneration in improving motor function of animals with complete spinal cord transection. However, some other issues such as promoting more neuronal relays formation, debugging wrong connections, and maintaining adequate neural circuits for functional recovery are urgent problems to be addressed.
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Objective To investigate the biochemical properties of rat improved perfusion-acellular pancreatic bioscaffold (APB).Methods The fresh pancreas from 10 rats were perfused through portal vein.The histological structure,ECM composition and DNA quantification of APB were evaluated.For the biocompatibility study,a 0.5 cm2 APB construct was surgically placed within a dorsal subcutaneous pocket of mice.Results The pancreatic tissue become translucent and the macroscopic three-dimensional architectures of native pancreas are retained after decellularization.The extracellular matrix (ECM) ultrastructures were well preserved.Immunofluorescence staining showed that collagen Ⅰ,Ⅳ,fibronectin and laminin were maintained in the APB after decellularization.DNA quantification of APB decreased significantly (P ＜ 0.05).The histological analysis of the subcutaneous implantation site showed the presence of immunological response surrounding the partially degraded APB.The histological remold score was 10.4 ± 1.8 at 14 days and 13.8 ± 1.3 at 28 days.The proliferation of AR42J cell line with the expression of amylase as the marker of exocrine acinar cells can be detected on the recellularized APB.Conclusion APB in this study met the stringent requirement to define a successful decellularization.The technique allowed the efficient generation of APB with preserved 3D architecture and represented a biocompatible scaffold capable of integrating within host tissue.
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Replacement therapy is the most effective method for the treatment of end-stage liver disease,and decellularized liver bioscaffold broadens the research field of the replacement therapy.The present liver bioscaffold preparation is to perfuse chemical reagents (detergents,enzymes,et al) into the vascular structure of the liver under certain physical conditions,so as to remove cellular components and retain extracellular matrix and microvascular structure.Cells were reseeded into the decellularized liver scaffold to obtain the recellularized liver,which can be cultured and evaluated in vitro or in vivo by observing the adhesion of seeded cells,detecting the synthesis and secretion of the recellularized liver.Currently,the selection of seed cells,recellularization protocol and recellularized liver transplantation are still under exploration.In this review,the preparation,evaluation,detection and application of the decellularized liver bioscaffold are introduced for the further experimental study and clinical research.
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10.3969/j.issn.2095-4344.2013.25.008