3D printing of nanoparticulate cartilage decellularized extracellular matrix for cartilage tissue engineering

Decellularized vascular matrix is a natural polymeric biomaterial that comes from arteries or veins which are removed the cellular contents by physical, chemical and enzymatic means, leaving only the cytoskeletal structure and extracellular matrix to achieve cell adhesion, proliferation and differentiation and creating a suitable microenvironment for their growth. In recent years, the decellularized vascular matrix has attracted much attention in the field of tissue repair and regenerative medicine due to its remarkable cytocompatibility, biodegradability and ability to induce tissue regeneration. Firstly, this review introduces its basic properties and preparation methods; then, it focuses on the application and research of composite scaffold materials based on decellularized vascular matrix in vascular tissue engineering in terms of current in vitro and in vivo studies, and briefly outlines its applications in other tissue engineering fields; finally, it looks into the advantages and drawbacks to be overcome in the application of decellularized vascular matrix materials. In conclusion, as a new bioactive material for building engineered tissue and repairing tissue defects, decellularized vascular matrix will be widely applied in prospect.

Engineering cartilage tissue interfaces using a natural glycosaminoglycan hydrogel matrix — An in vitro study

Advantages and challenges offered by biofunctional core–shell fiber systems for tissue engineering and drug delivery

Concentration dependent survival and neural differentiation of murine embryonic stem cells cultured on polyethylene glycol dimethacrylate hydrogels possessing a continuous concentration gradient of n-cadherin derived peptide His-Ala-Val-Asp-Lle.

US patents relating to compositions containing extracellular matrix material and methods of using extracellular material in tissue engineering and regenerative medicine are being granted at rapid pace. This article briefly describes some of these US patents and their claims. The large number of patents being issued on extracellular material and its uses indicates that there remains strong commercial interest and innovation in this area of tissue engineering and regenerative medicine.

Tissue engineering (TE) is an interdisciplinary field involving principles of engineering and biological sciences to fabricate new tissue and organs using cells and scaffolds. It is expected to play an important role in the therapeutic approach in the current and future medicine. In the coming years, there will be an increased emphasis on the usage of biomaterials that can be integrated forming a renewable interface with prosthetic implants for regenerated medicine and cell based TE on a long term basis. In this regard, significant consideration is being given to natural cationic chitosan as a matrix for TE. Chitosan is a linear polysaccharide, produced from crustacean sources. Recent studies suggest that chitosan based matrixes are promising for TE applications. The authors describe here the uniqueness and versatility of chitosan in bone and cartilage TE in terms of structure–property relationship of chitosan scaffolds.

Nanostructured chitosan/gelatin/bioactive glass in situ forming hydrogel composites as a potential injectable matrix for bone tissue engineering

The extracellular matrix is a key component during regeneration and maintenance of tissues and organs, and it therefore plays a critical role in successful tissue engineering as well. Tissue engineers should recognise that engineering technology can be deduced from natural repair processes. Due to advances in such distinct areas as biology, engineering, physics and chemistry and the possibility of using robotics to facilitate the search for new treatments, we can identify the basic principles and extrapolate them into tools to mimic the regenerative process. Ubiquitously distributed throughout the body, the extracellular matrix surrounding the cells plays a key instructive role, in addition to the previously recognised supportive role. In this review we will highlight the role of the extracellular matrix and discuss the latest technological possibilities to exploit the extracellular matrix in tissue engineering.

The extracellular matrix is produced by the resident cells in tissues and organs, and secreted into the surrounding medium to provide biophysical and biochemical support to the surrounding cells due to its content of diverse bioactive molecules. Recently, the extracellular matrix has been used as a promising approach for tissue engineering. Emerging studies demonstrate that extracellular matrix scaffolds are able to create a favorable regenerative microenvironment, promote tissue-specific remodeling, and act as an inductive template for the repair and functional reconstruction of skin, bone, nerve, heart, lung, liver, kidney, small intestine, and other organs. In the current review, we will provide a critical overview of the structure and function of various types of extracellular matrix, the construction of three-dimensional extracellular matrix scaffolds, and their tissue engineering applications, with a focus on translation of these novel tissue engineered products to the clinic. We will also present an outlook on future perspectives of the extracellular matrix in tissue engineering and regenerative medicine.

Chapter 6 - Functions and applications of extracellular matrix in cartilage tissue engineering

细胞外基质材料的研究是组织工程中一项重要而紧迫的任务.本文就其材料选择、制备方法、影响因素和表面修饰等方面的研究现状进行了较系统的综述,并指出了当前细胞外基质材料研究所面临的问题以及未来的研究方向.

Natural polypeptides-based electrically conductive biomaterials for tissue engineering

BackgroundEndothelial cells line blood vessels and the heart where they release cardio-protective hormones that prevent thrombosis. Available replacements to treat heart valve diseases are limited by the lack of the endothelial cell layer, making them susceptible to calcification and thrombosis, which limits utility and increases the need for multiple replacements[1]. A suggested solution is to adapt tissue engineering techniques to formulate intelligent instructive scaffolds decorated with specific molecules to enhance the adhesion and population of circulating progenitor endothelial cells from the blood.AimIn this study, we aim to modulate nanofibrous scaffolds fabricated from the biodegradable polyster polycaprolactone (PCL) to provide a viable environment for endothelial cells from blood progenitors (blood outgrowth endothelial cells; BOECs) to adhere, proliferate and function successfully. To date we have (i) compared the behaviour of BOECs to endothelial cells isolated from human heart valves (hVECs) under shear conditions, (ii) tested the compatibility of PCL with BOECs by assessing cell viability and inflammatory responses on modified PCL films, and their ability to populate structured PCL scaffolds.MethodsBOECs were isolated from the blood of healthy volunteers by selective plating of peripheral blood mononuclear cells (PBMCs), and phenotyping was assured by measuring the expression of endothelial cell markers using fluorescent activated cell sorting (FACS). hVECs were isolated from human aortic valves by collagenase digestion. Shear stress was studied using a cone and plate model. PCL films were prepared by solvent evaporation method, and sterilized with ethanol for 30 min, or modified by plasma oxidation at 30 w and 0.1 m bar for 30 min. PCL Films were coated with extracellular matrix proteins before cell seeding. After 72 hr of culture, cell viability was measured using alamar blue and cell secretory function measured by the release of CXCL8, endothelin-1 (ET-1) and prostacyclin by ELISA. Finally, the ability of these cells to populate 3D structured nanofibrous PCL scaffolds fabricated by jet spraying technique2 was determined by confocal microscopy of phalloidin stained cells.ResultsBOECs colonies appeared at between 7 and 21 days of culture. FACS analysis of expanded cells showed positive expression of the typical endothelial cell markers CD31, CD90, VE Cadherin, CD44, and CD105. Also, BOECs stained negative for the (non-endothelial) exclusion markers CD14, CD45, and CD133. In shear stress studies, BOECs and hVECs aligned similarly to ventricular flow (ie. directional shear stress). Both cell types displayed similar viability responses when grown on PCL which was ∼40% less than achieved when cells were grown on control glass slides. Modifying PCL with plasma oxidation or extracellular matrix coating did not improve viability of either cell type. Both BOECs and hVECs released CXCL8 and ET-1 when grown on control glass slides which was not increased in cells cultured on PCL. In addition, both cell types released the cardio-protective hormone prostacyclin when grown on glass or PCL, suggesting that they would provide a viable anti-thrombotic surface. Regarding to 3D structures, BOECs were able to populate both modified and unmodified aligned nanofibrous PCL scaffolds, and appeared to align with the direction of the fibres.ConclusionsBOECs expressed the requisite endothelial cell markers and, as we have shown previously, responded appropriately to shear and released CXCL8, ET-1 and prostacyclin 3; suggesting that BOECs are suitable seeding cells for tissue engineering. For the endothelialization of tissue engineered heart valves, the target cells that BOECs need to mimic are hVECs. Our preliminary studies show that BOECs and hVECs profile similarly in population of PCL, alignment with shear stress and with endothelial cell hormone release. In addition, BOECs are able to align with the direction of PCL fibres, mimicking the native valve endothelial cells that were previously reported to align with the direction of the collagen fibers[4]. These results are promising and indicate the potential of BOECs as a cell source to populate PCL nanofibrous scaffolds designed to replace heart valves. Nevertheless, our data shows that standard PCL platforms are not optimal in terms of cell viability. This may be improved by biofunctionalizing PCL with specific molecules to support BOECs adhesion and proliferation. For that, we are currently studying the potential of linking the BOECs specific peptide (TPS) to PCL.

Native and artificial extracellular matrices (ECMs) have been widely applied in biomedical fields as one of the most effective components in tissue regeneration. In particular, ECM-based drugs are expected to be applied to treat diseases in organs relevant to urology, because tissue regeneration is particularly important for preventing the recurrence of these diseases. Native ECMs provide a complex in vivo architecture and native physical and mechanical properties that support high biocompatibility. However, the applications of native ECMs are limited due to their tissue-specificity and chemical complexity. Artificial ECMs have been fabricated in an attempt to create a broadly applicable scaffold by using controllable components and a uniform formulation. On the other hands, artificial ECMs fail to mimic the properties of a native ECM; consequently, their applications in tissues are also limited. For that reason, the design of a versatile, hybrid ECM that can be universally applied to various tissues is an emerging area of interest in the biomedical field.

The extracellular matrix (ECM) is a non-cellular and gelatinous component of tissues, rich in proteins and proteoglycans, that provides information about the environment, forms a reservoir of trophic factors and regulates cell behavior by binding and activating cell surface receptors. This important network acts as a scaffold for tissues and organs throughout the body, playing an essential role in their structural and functional integrity. It is essential for cells to connect and communicate with each other and play an active role in intracellular signaling. Due to these properties, in recent decades the potential of the extracellular matrix in tissue engineering has begun to be explored with the aim of developing innovative biomaterials to be used in regenerative medicine. This review will first outline the components of the extracellular matrix in the peripheral nerve, followed by an exploration of its role in the regeneration process after injury, with a focus on the mechanisms underlying its interactions with nerve cells. Qualitative and quantitative methods used for extracellular matrix analysis will be described, and finally an overview will be given of recent advances in nerve repair strategies that exploit the potential of the extracellular matrix to enhance regeneration, highlighting the critical issues of extracellular matrix molecule use and proposing new directions for future research.