Search results for "Acellular"
showing 10 items of 1986 documents
A Hydrogel Derived From Decellularized Dermal Extracellular Matrix. Biomaterials
2012
The ECM of mammalian tissues has been used as a scaffold to facilitate the repair and reconstruction of numerous tissues. Such scaffolds are prepared in many forms including sheets, powders, and hydrogels. ECM hydrogels provide advantages such as injectability, the ability to fill an irregularly shaped space, and the inherent bioactivity of native matrix. However, material properties of ECM hydrogels and the effect of these properties upon cell behavior are neither well understood nor controlled. The objective of this study was to prepare and determine the structure, mechanics, and the cell response in vitro and in vivo of ECM hydrogels prepared from decellularized porcine dermis and urinar…
Mesenchymal and Induced Pluripotent Stem Cells-Derived Extracellular Vesicles: The New Frontier for Regenerative Medicine?
2020
Regenerative medicine aims to repair damaged, tissues or organs for the treatment of various diseases, which have been poorly managed with conventional drugs and medical procedures. To date, multimodal regenerative methods include transplant of healthy organs, tissues, or cells, body stimulation to activate a self-healing response in damaged tissues, as well as the combined use of cells and bio-degradable scaffold to obtain functional tissues. Certainly, stem cells are promising tools in regenerative medicine due to their ability to induce de novo tissue formation and/or promote organ repair and regeneration. Currently, several studies have shown that the beneficial stem cell effects, espec…
Endothelial cell colonization and angiogenic potential of combined nano- and micro-fibrous scaffolds for bone tissue engineering
2008
Presently the majority of tissue engineering approaches aimed at regenerating bone relies only on postimplantation vascularization. Strategies that include seeding endothelial cells (ECs) on biomaterials and promoting their adhesion, migration and functionality might be a solution for the formation of vascularized bone. Nano/micro-fiber-combined scaffolds have an innovative structure, inspired by extracellular matrix (ECM) that combines a nano-network, aimed to promote cell adhesion, with a micro-fiber mesh that provides the mechanical support. In this work we addressed the influence of this nano-network on growth pattern, morphology, inflammatory expression profile, expression of structura…
Polylactide-based materials science strategies to improve tissue-material interface without the use of growth factors or other biological molecules
2018
In a large number of medical devices, a key feature of a biomaterial is the ability to successfully bond to living tissues by means of engineered mechanisms such as the enhancement of biomineralization on a bone tissue engineering scaffold or the mimicking of the natural structure of the extracellular matrix (ECM). This ability is commonly referred to as "bioactivity". Materials sciences started to grow interest in it since the development of bioactive glasses by Larry Hench five decades ago. As the main goal in applications of biomedical devices and tissue scaffolds is to obtain a seamless tissue-material interface, achieving optimal bioactivity is essential for the success of most biomate…
A new printable and durable N,O-carboxymethyl chitosan–Ca2+–polyphosphate complex with morphogenetic activity
2015
Biomimetic materials have been gaining increasing importance in tissue engineering since they may provide regenerative alternatives to the use of autologous tissues for transplantation. In the present study, we applied for bioprinting of a functionalized three-dimensional template, N,O-carboxymethyl chitosan (N,O-CMC), mimicking the physiological extracellular matrix. This polymer, widely used in tissue engineering, has been provided with functional activity by integration of polyphosphate (polyP), an osteogenically acting natural polymer. The two polymers, N,O-CMC and polyP, are linked together via Ca2+ bridges. This N,O-CMC + polyP material was proven to be printable and durable. The N,O-…
Meso-scale topological cues influence extracellular matrix production in a large deformation, elastomeric scaffold model
2018
Physical cues are decisive factors in extracellular matrix (ECM) formation and elaboration. Their transduction across scale lengths is an inherently symbiotic phenomenon that while influencing ECM fate is also mediated by the ECM structure itself. This study investigates the possibility of enhancing ECM elaboration by topological cues that, while not modifying the substrate macro scale mechanics, can affect the meso-scale strain range acting on cells incorporated within the scaffold. Vascular smooth muscle cell micro-integrated, electrospun scaffolds were fabricated with comparable macroscopic biaxial mechanical response, but different meso-scale topology. Seeded scaffolds were conditioned …
Preparation and characterization of a biologic scaffold from esophageal mucosa
2013
Biologic scaffolds composed of extracellular matrix (ECM) are commonly used to facilitate a constructive remodeling response in several types of tissue, including the esophagus. Surgical manipulation of the esophagus is often complicated by stricture, but preclinical and clinical studies have shown that the use of an ECM scaffold can mitigate stricture and promote a constructive outcome after resection of full circumference esophageal mucosa. Recognizing the potential benefits of ECM derived from homologous tissue (i.e., site-specific ECM), the objective of the present study was to prepare, characterize, and assess the in-vivo remodeling properties of ECM from porcine esophageal mucosa. The…
Morphostructural analysis of human follicular stem cells on highly porous bone hydroxyapatite scaffold
2007
In this study we investigated the in vitro behaviour, morphostructure and extracellular matrix synthesis of human dental follicular stem cells (hDFSCs) isolated from human dental bud, which resulted to be positive for mesenchymal markers (CD29, CD90, CD146 and CD166) by FACS analysis. Cells were analysed by light and electronic microscopy to evaluate their biological response either at week 1, that is before differentiation, or at weeks 3–6, when they had been cultured in osteogenic medium onto a highly porous natural scaffold material (Bio-Oss®). Microscopy analysis of primary culture cells showed they had a mesenchymal stem cell-like morphostructure, spindle shaped, similar to the cultur…
Compromised nuclear envelope integrity drives tumor cell invasion
2020
AbstractWhile mutations leading to a fragile envelope of the cell nucleus are well known to cause diseases such as muscular dystrophies or accelerated aging, the pathophysiological consequences of the recently discovered mechanically induced nuclear envelope ruptures in cells harboring no mutation are less known. Here we show that repeated loss of nuclear envelope integrity in nuclei experiencing mechanical constraints promotes senescence in nontransformed cells, and induces an invasive phenotype including increased collagen degradation in human breast cancer cells, both in vitro and in a mouse xenograft model of breast cancer progression. We show that these phenotypic changes are due to th…
Compromised nuclear envelope integrity drives TREX1-dependent DNA damage and tumor cell invasion
2021
Although mutations leading to a compromised nuclear envelope cause diseases such as muscular dystrophies or accelerated aging, the consequences of mechanically induced nuclear envelope ruptures are less known. Here, we show that nuclear envelope ruptures induce DNA damage that promotes senescence in non-transformed cells and induces an invasive phenotype in human breast cancer cells. We find that the endoplasmic reticulum (ER)-associated exonuclease TREX1 translocates into the nucleus after nuclear envelope rupture and is required to induce DNA damage. Inside the mammary duct, cellular crowding leads to nuclear envelope ruptures that generate TREX1-dependent DNA damage, thereby driving the …