As the largest barrier organ in the human body, once skin defect occur, it not only affects appearance but also cause clinical problems such as infections. Traditional skin defect repair methods, such as autologous skin transplantation and allogeneic skin transplantation, have shortcomings such as limited donor sources, potential immune rejection, and limited repair effects, and are difficult to meet the individualized treatment needs of complex wounds. Bioprinting technology, as a breakthrough approach in tissue engineering in recent years, can accurately control the spatial distribution of seed cells and biomaterials within scaffolds based on digital models, achieving personalized biomimetic structure of skin tissue. This article aims to summarize the application and research progress of bioprinting technology in skin tissue engineering, providing a theoretical basis for its further clinical application.
Objective To review the biochemical characteristics, appl ication progress, and prospects of the adiposederived stem cells (ADSCs). Methods The recent original experimental and cl inical l iterature about ADSCs was extensively reviewed and analyzed. Results ADSCs can be readily harvested in large numbers from adipose tissue with properties of stable prol iferation and potential differentiation in vitro. Significant progress of ADSCs is made in the animal experimentand the cl inical appl ication. It has been widely used in the cl inical treatment of cardiovascular disease, metabol ic disease, encephalopathy, and tissue engineering repair. Conclusion ADSCs have gradually replaced bone marrow mesenchymal stem cells and become the focused hot spot of regenerative medicine and stem cells.
Abstract: The amniotic fluidderived stem cells (AFSC) possess considerable advantageous characteristics including high proliferation potential, easy availability, low immunogenicity and oncogenicity，and accordance with medical ethnics. Moreover, they do not require the sacrifice of human embryos for their isolation and the cells can differentiate into all three kinds of germs. Accordingly，they initiate a new and very promising field in stem cell research and they will be a potential source of stem cells for therapies related to regeneration medicine of cardiovascular diseases. The research about the AFSC utilization in cardiovascular diseases is just started. Though there were some exciting breakthroughs, there still remain many challenges. In the article，we will discuss AFSC characteristics, influence of amniotic fluid harvesting time on stem cells, isolation and purification, emphasizing mainly on the potential of AFSC differentiation into cardiovascular cells, current situation and problems in this field.
Objective To introduce types and differentiation potentials of stem cells from adipose tissue, and its applications on regenerative medicine and advantages. Methods The literature of original experimental study and clinical research about bone marrow mesenchymal stem cells (BMSCs), adipose-derived stem cells (ADSCs), and dedifferentiated fat (DFAT) cells was extensively reviewed and analyzed. Results ADSCs can be isolated from stromal vascular fraction. As ADSCs have multi-lineage potentials, such as adipogenesis, osteogenesis, chondrogenesis, angiogenesis, myogenesis, and neurogenesis, they have already been successfully used in regenerative medicine areas. Dramatically, mature fat cells can be dedifferentiated and changed into fibroblast-like cells, named DFAT cells, via ceiling culture method. DFAT cells also had the same multi-lineage potentials as ADSCs, differentiating into adipocytes, osteocytes, chondrocytes, endothelial cells, muscle cells, and nerve cells. Compared with BMSCs which are commonly used as adult stem cells, ADSCs and DFAT cells have extensive sources and can be easily acquired. While compared with ADSCs, DFAT cells have good homogeneity and b proliferation capacity. Conclusion As a potential source of stem cells, adipose tissue will provide a new promising for regenerative medicine.
Decellularized extracellular matrix (dECM) has been widely used as a scaffold for regenerative medicine due to its high biomimetic and excellent biocompatibility. As a functional polymer material with high water content and controlled fluidity, hydrogel is very promising for some minimally invasive surgery in clinical practice. In recent years, with the rapid development of hydrogel theory and technology, dECM hydrogel has gradually become a research hotspot in the field of regenerative medicine. In this paper, the related researches in recent years are reviewed regarding the preparation of dECM hydrogel and its preclinical application. The future clinical use is also prospected.
Objective To review the development of the liver stem cell transplant for the liver regenerative treatment. Methods The transplantationrelated articles about the stem cell classification, repairing mechanisms, administration routes, and existing problems in the liver regenerative therapies reported in the latest literature were extensively reviewed. Results The related liverrepairing stem cells were found to be inside and outside the liver, i.e., the hepatic stem cells and the nonhepatic stem cells. They could repair the liver by the mechanism of the cell fusion or the celltransdifferentiation. The stem cells could be administrated via the portal vein. However, the application of the liver stem cell transplant was restricted by many related clinical problems. Conclusion Further studies are still needed for an improvement of the clinical feasibility for the stem cell transplantation, especially for the liver stem cell transplantation.
Objective To investigate the latest development of tissue engineeredregenerative medicine in industrialization, with the intention to direct work in practical area. Methods A complete insight of regenerative medicine in industrialization was obtained through referring to update publications, visiting related websites, as well as learning from practical experience. Results The aerial view of the future of regenerative medicine was got based on knowledge of four different tissue engineering projects. Conclusion All present efforts should be devoted to regenerative medicine area meeting the industrialized trends.
Objective To introduce the related issues in the clinical translational application of adipose-derived stem cells (ASCs). Methods The latest papers were extensively reviewed, concerning the issues of ASCs production, management, transportation, use, and safety during clinical application. Results ASCs, as a new member of adult stem cells family, bring to wide application prospect in the field of regenerative medicine. Over 40 clinical trials using ASCs conducted in 15 countries have been registered on the website (http://www.clinicaltrials.gov) of the National Institutes of Health (NIH), suggesting that ASCs represents a promising approach to future cell-based therapies. In the clinical translational application, the related issues included the quality control standard that management and production should follow, the prevention measures of pathogenic microorganism pollution, the requirements of enzymes and related reagent in separation process, possible effect of donor site, age, and sex in sampling, low temperature storage, product transportation, and safety. Conclusion ASCs have the advantage of clinical translational application, much attention should be paid to these issues in clinical application to accelerate the clinical translation process.
Cell sheet engineering is an important technology to harvest the cultured cells in the form of confluent monolayers using a continuous culture method and a physical approach. Avoiding the use of enzymes, expended cells can be harvested together with endogenous extracellular matrix, cell-matrix contacts, and cell-cell contacts. With high efficiency of cell loading ability and without using exogenous scaffolds, cell sheet engineering has several advantages over traditional tissue engineering methods. In this article, we give an overview on cell sheet technology about its applications in the filed of tissue regeneration, including the construction of soft tissues (corneal, mucous membrane, myocardium, blood vessel, pancreas islet, liver, bladder and skin) and hard tissues (bone, cartilage and tooth root). This techonoly is promising to provide a novel strategy for the development of tissue engineering and regenerative medicine. And further works should be carried out on the operability of this technology and its feasibility to construct thick tissues.