Experimental Advance in Seed Cells and Biological Scaffolds for Spinal Cord Tissue Engineering (review) / 中国康复理论与实践

Objective:To explore the problems of seed cells and biological scaffolds in spinal cord tissue engineering, and review the recent experimental research. Methods:Related literatures were searched in CNKI, Wangfang data, PubMed and Web of Science from establishment to March, 2021, and the problems and progress of seed cells, biological scaffolds and their combination were reviewed. Results:The problems of seed cells are carcinogenicity, immune rejection, ethics, low survival rate and differentiation rate after transplantation, and current researches focus on exploring new cell types, gene transfection, cell co-transplantation and pretreatment before transplantation. The problems of biological scaffold are that a single material selection cannot meet different needs, and the traditional technology cannot simulate the internal structure of spinal cord well. There were more researches focusing on new composite materials and new technology. The core problem of their combination is that the effects of different cell and scaffold combinations are different, and the current researches are mostly devoted to the continuous exploration of suitable composite mode, and try to introduce biological agents and other factors. Conclusion:Spinal cord tissue engineering has the potential to completely change the therapeutic pathway of spinal cord injury. Current experimental researches mainly base on solving the problems of seed cells and biological scaffolds of spinal cord tissue engineering, and further explore the appropriate composite mode of seed cells and biological scaffolds, so as to provide more basic evidence for its clinical application.

Construction of acellular porcine bladder scaffolds / 中国组织工程研究

BACKGROUND: Bladder repair is currently one of the main treatments for bladder defects. Homologous tissue is less affected by various factors. Tissue engineered acellular bladder matrix has become an increasing area of interest. Porcine bladder acellular matrix has a wide range of sources and has a natural extracellular scaffold structure, which has become a hot topic in tissue engineering bladder substitute materials. OBJECTIVE: To explore the feasibility of acellular porcine bladder as a tissue engineering scaffold material. METHODS: The cell-free matrix of pig bladder was prepared by liquid nitrogen freezing and thawing, dodecyl sodium sulfate and trypsin decellularization method. According to different decellularization methods, pig bladders were divided into normal control group (without any treatment), experimental group (treated with 0.6% trypsin and 5% sodium lauryl sulfate (pH 8.0)) and acellular control group (treated with 0.75% trypsin (pH 8.0), 1% trypsin (pH 8.0), 5% sodium lauryl sulfate (pH 7.6) or 10% sodium dodecyl sulfate (pH 7.6)). The decellularization effect of pig bladder was observed by hematoxylin-eosin staining, van Gieson staining, DNA quantification, and α-Gal antigen detection. RESULTS AND CONCLUSION: Hematoxylin-eosin staining revealed that in the experimental group, the components of the bladder cells of the pigs were basically removed. van Gieson staining revealed that the DNA residues and α-Gal antigen residues in the cells were significantly lower than those in the control group (P < 0.05). These results suggest that treatment of pig bladder with 0.6% trypsin and 5% sodium dodecyl sulfate can effectively remove its cellular components while retaining the extracellular matrix of porcine bladder tissue. This provides a reference value for constructing accelular porcine bladder scaffolds.

Cell Therapy and Tissue Engineering Approaches for Cartilage Repair and/or Regeneration

Articular cartilage injuries caused by traumatic, mechanical and/or by progressive degeneration result in pain, swelling, subsequent loss of joint function and finally osteoarthritis. Due to the peculiar structure of the tissue (no blood supply), chondrocytes, the unique cellular phenotype in cartilage, receive their nutrition through diffusion from the synovial fluid and this limits their intrinsic capacity for healing. The first cellular avenue explored for cartilage repair involved the in situ transplantation of isolated chondrocytes. Latterly, an improved alternative for the above reparative strategy involved the infusion of mesenchymal stem cells (MSC), which in addition to a self-renewal capacity exhibit a differentiation potential to chondrocytes, as well as a capability to produce a vast array of growth factors, cytokines and extracellular matrix compounds involved in cartilage development. In addition to the above and foremost reparative options up till now in use, other therapeutic options have been developed, comprising the design of biomaterial substrates (scaffolds) capable of sustaining MSC attachment, proliferation and differentiation. The implantation of these engineered platforms, closely to the site of cartilage damage, may well facilitate the initiation of an \'in situ' cartilage reparation process. In this mini-review, we examined the timely and conceptual development of several cell-based methods, designed to repair/regenerate a damaged cartilage. In addition to the above described cartilage reparative options, other therapeutic alternatives still in progress are portrayed.

Experimental Study on Self-assembly of KLD-12 Peptide Hydrogel and 3-D Culture of MSC Encapsulated within Hydrogel In Vitro / 华中科技大学学报（医学）（英德文版）

o-fiber hydrogel in vitro. MSCs in KLD-12 peptide hydrogel grew well and proliferated with the culture time. KLD-12 peptide hydrogel can serve as an excellent injectable material of biological scaffolds in tissue engineering of IVD.