Activity

© 2020 Elsevier Inc. All rights reserved.Decellularized corneal scaffolds have the potential to be used as alternatives to donor corneas during keratoplasty. Here a decellularization technique is described that involves the use of sodium dodecyl sulfate, Triton-X100, DNAse and RNAse to remove cells and cellular constituents. We have previously found that this combination of chemicals and enzymes to be effective at removing cells while retaining extracellular matrix proteins. In addition, different methods for assessing if the decellularization process has been successful are discussed. These include techniques to identify and quantify the presence of cells, DNA and extracellular matrix components as well as methods to examine the collagen fibril organization and scaffold transparency. © 2020 Elsevier Inc. All rights reserved.Supercritical carbon dioxide (scCO2) is being used as an alternative approach to the traditional methods for the decellularization of tissues. This chapter describes the use of scCO2 for the decellularization of optic nerve, myocardium, and cornea tissues. The main goal of this method is to burst the cells with high-pressure, remove them from the tissues and to maintain the extracellular matrix structure of the native tissues. For this purpose, several scCO2-assisted decellularization protocols were developed and optimized according to the requirements of these tissues. Efficiencies of the utilized decellularization protocols were determined via histological and morphological analysis. The decrease in the DNA content and the preserved glycosaminoglycan (GAG) amounts were also used as assessment parameters. © 2020 Elsevier Inc. All rights reserved.Human amniotic membrane (HAM) has been used as a very promising biological-based product in health centers, especially for skin and cornea wound healing applications. The excellent properties of this membrane make it a potential candidate in treatment of various skin injuries such as bedsores, burn wounds and diabetic ulcers. Such properties are cytobiocompatibility, a structure very similar to normal skin composed of extracellular matrix (ECM) proteins, various growth factors involved in normal wound healing process and antibacterial agents. HAM contains epithelial cells, fibroblasts and mesenchymal stem cells. Therefore, the successful decellularization of HAM with minimal negative effects on its ECM components is very important to avoid graft rejection and shows improved performance. To date, several approaches have been conducted for decellularization of HAM, which is mainly based on enzyme-, detergent- or mechanical procedures with various ranges of success. Here, we describe a systematic detergent-based decellularization protocol as main protocol. We also explain the enzyme- and mechanical-based methods as the alternative protocols for decellularization of HAM. © 2020 Elsevier Inc. All rights reserved.The use of hydrogels derived from the extracellular matrix (ECM) in tissue engineering applications aims to overcome the conundrum of mimicking the complexity of ECM composition in vitro. see more In this chapter, we describe a method of decellularization and subsequent formation of an ECM-based hydrogel using porcine heart tissue. These decellularized ECM hydrogels could be used to create semi-interpenetrating networks or as bioinks in bioprinting applications to further enhance the bioactivity and increase the biomimicry degree of the biological cardiac constructs. © 2020 Elsevier Inc. All rights reserved.The human placenta is considered a biological waste, thus it is a great source of extracellular matrix (ECM) proteins. The human chorion membrane (HCM) is a membrane that composes the human placenta and is constituted by collagens type I, II, IV, V and VI, fibronectin and laminin. To the best of our knowledge, the potential of HCM alone is largely unexplored as a substrate to be used in tissue engineering and regenerative medicine. In this work, we describe, for the first time, the process and method to decellularize the chorion membrane alone. To verify the success of the decellularization protocol, the presence and distribution of cell nuclei and double-stranded DNA were quantified and analyzed by DAPI staining, PicoGreen and electrophoresis. After the decellularization protocol an ECM compact and handleably membrane is obtained, the decellularized human chorion membrane (dHCM). © 2020 Elsevier Inc. All rights reserved.Tendon injuries continuously rise, and regeneration is not only slow, but also limited due to the poor endogenous healing ability of the tendon tissue. Tissue grafts constitute the clinical gold standard treatment for severe injuries, but inherent limitations drive the field toward tissue engineering approaches to create suitable tissue constructs. Recapitulation of the native microenvironment represent a key challenge for the development of tendon tissue equivalents in vitro that can be further utilized as implantable devices. Methods to maintain cellular phenotype and to enhance extracellular matrix deposition for accelerated development of tissue-like modulus should be developed. Herein, we assessed the combining effect of surface topography and macromolecular crowding in human tenocyte culture. Our data demonstrated that bidirectionally aligned electrospun fibers induce physiological cell growth, while macromolecular crowding enhanced and accelerated tissue-specific extracellular matrix deposition. Collectively, these data advocate the use of multifactorial approaches for the accelerated development of functional tissue-like surrogates in vitro. © 2020 Elsevier Inc. All rights reserved.The inability of cartilage tissue to self-heal due to its avascular nature often leads to conditions such as osteoarthritis, traumatic rupture of cartilage, and osteochondrosis. The cartilage provides cushioning effects between the joints and avoids bone frictions. The extracellular matrix (ECM) of cartilage consists predominantly of collagens, elastin, proteoglycans and glycoproteins. A number of tissue engineered ECM derived biological scaffolds and matrices are available for cartilage regeneration. The decellularized tissues provide appropriate bioactive cues in the absence of cellular components, hence avoiding immunological issue. However, the decellularization process involves several cellular disruption techniques that may alter the ECM architecture affecting bioactivity. Therefore, development of cell-free cartilage biomaterials with unaltered ECM integrity and bioactivity is of paramount necessity by smart selection of modified techniques and agents. Herein, we described about various decellularization methods, agents, techniques, and their applications in tissue/cartilage decellularization.