Types Of Extracellular Matrix Research Articles

Native and cell-derived extracellular matrix exhibit disparate immunogenic and immunomodulatory effects

Abstract The extracellular matrix (ECM) represents the natural environment of the cells and consists of various fibrous and non-fibrous proteins. It can be generated by decellularization of native tissue (dECM) or by isolation from cultured cells in vitro (cdECM). In the present study the immunomodulatory effect of dECM from native adipose tissue and cdECM from adipose derived stem cells (cdECM) on monocytes and ASCs encapsulated in gellan gum-ECM hybrid hydrogels was investigated. The monocyte activation test revealed a higher secretion of IL6 and TNFα in monocytes incubated with dECM compared to cdECM. Encapsulated ASCs in gellan gum-ECM-hybrid hydrogels exhibit different cytokine profiles (IL8, IL6, MCP-1, TNFα) when cultured with dECM or cdECM or gellan gum alone. The demonstrated differences in cellular behavior in the present of the two different types of ECM should be considered when using them as a biomaterial for in vitro as well as in vivo applications.

Oligodendrocyte differentiation on murine decellularized brain tissue.

Loss of oligodendrocytes causes severe neurological damage. Oligodendrogenesis is the production of new oligodendrocytes throughout life and includes several developmental stages starting from oligodendrocyte precursor cells (OPCs). The GPR17-expressing cell population, an important intermediate stage in oligodendrocyte development, acts as a reservoir responding to brain injury and ischemia. GPR17 plays a complex role in oligodendrocyte maturation and response to injury; its activation promotes differentiation into more mature phenotypes. However, our understanding of GPR17-expressing oligodendrocytes in vitro remains limited No methods have been elucidated for studying these short-lived and changeable cell populations using culture systems. The extracellular matrix (ECM) plays an important role in regulating the proliferation and differentiation of these cells; however, conventional two-dimensional culture systems cannot reproduce the complex structure and environmental conditions of the ECM in vivo. Herein, a culture system with decellularized brain tissue that retains organized ECM scaffolds was introduced to better mimic the in vivo environment. This system enabled the study of interactions between OPCs, ECM, and other cell types. Neurospheres containing progenitor cells that differentiate into oligodendrocyte lineage cells, neurons, and astrocytes were transplanted into decellularized brain slices. The results showed that this method not only promoted stem cell differentiation but also significantly enhanced differentiation into oligodendrocytes when supplemented with oligospheric buffer. This model system provides a better understanding of the interaction between OPCs and the ECM and a novel approach for studying the differentiation of GPR17-expressing cells, which may be useful for future therapeutic strategies for promoting remyelination and central nervous system repair.

Glutathione: A Key Regulator of Extracellular Matrix and Cell Death in Intervertebral Disc Degeneration.

Intervertebral disc degeneration (IVDD) is a degenerative disease accompanied by the loss of nucleus pulposus cells and the degradation of extracellular matrix (ECM), which tends to be associated with lower back pain. The ECM and various types of cell death in IVDD are regulated by multiple factors, such as inflammatory responses and oxidative stress. The glutathione (GSH) redox system is the most important antioxidant defense system in cells. GSH is one of the most abundant thiol antioxidants in mammalian cells, which functions directly and indirectly by scavenging peroxides through the GSH redox system. In these reactions, GSH is oxidized by electrophilic substances, such as reactive oxygen species and free radicals, to form glutathione disulfide to exert antioxidative effects. It has been reported that GSH can protect cells against the damage of oxidative stress and various pathophysiological stimulus that can lead to different types of cell death. In addition, it was reported that the level of GSH widely participates in apoptosis, autophagy, ferroptosis, and oxidative stress in many diseases including osteoarthritis and IVDD. Therefore, we summarized the effects of GSH on ECM metabolism and cells' functions during IVDD. In addition, we summarized the regulatory effects of small molecule compounds on GSH to explore potential ways to regulate the level of GSH. Better understanding the underlying role of GSH in regulating IVDD will facilitate the goal of preventing and retarding the progress of IVDD in the future.

Reaching the Tumor: Mobility of Polymeric Micelles Inside an In Vitro Tumor-on-a-Chip Model with Dual ECM.

Degradable polymeric micelles are promising drug delivery systems due to their hydrophobic core and responsive design. When applying micellar nanocarriers for tumor delivery, one of the bottlenecks encountered in vivo is the tumor tissue barrier: crossing the dense mesh of cells and the extracellular matrix (ECM). Sometimes overlooked, the extracellular matrix can trap nanoformulations based on charge, size, and hydrophobicity. Here, we used a simple design of a microfluidic chip with two types of ECM and MCF7 spheroids to allow "high-throughput" screening of the interactions between biological interfaces and polymeric micelles. To demonstrate the applicability of the chip, a small library of fluorescently labeled polymeric micelles varying in their hydrophilic shell and hydrophobic core forming blocks was studied. Three widely used hydrophilic shells were tested and compared, namely, poly(ethylene glycol), poly(2-ethyl-2-oxazoline), and poly(acrylic acid), along with two enzymatically degradable dendritic hydrophobic cores (based on hexyl or nonyl end groups). Using ratiometric imaging of unimer:micelle fluorescence and FRAP inside the chip model, we obtained the local assembly state and dynamics inside the chip. Notably, we observed different micelle behaviors in the basal lamina ECM, from avoidance of the ECM structure to binding of the poly(acrylic acid) formulations. Binding to the basal lamina correlated with higher uptake into MCF7 spheroids. Overall, we proposed a simple microfluidic chip containing dual ECM and spheroids for the assessment of the interactions of polymeric nanocarriers with biological interfaces and evaluating nanoformulations' capacity to cross the tumor tissue barrier.

Extracellular Matrix Collagen I Differentially Regulates the Metabolic Plasticity of Pancreatic Ductal Adenocarcinoma Parenchymal Cell and Cancer Stem Cell.

Pancreatic ductal adenocarcinoma (PDAC) has a 5-year survival rate of less than 10 percent largely due to the intense fibrotic desmoplastic reaction, characterized by high levels of extracellular matrix (ECM) collagen I that constitutes a niche for a subset of cancer cells, the cancer stem cells (CSCs). Cancer cells undergo a complex metabolic adaptation characterized by changes in metabolic pathways and biosynthetic processes. The use of the 3D organotypic model in this study allowed us to manipulate the ECM constituents and mimic the progression of PDAC from an early tumor to an ever more advanced tumor stage. To understand the role of desmoplasia on the metabolism of PDAC parenchymal (CPC) and CSC populations, we studied their basic metabolic parameters in organotypic cultures of increasing collagen content to mimic in vivo conditions. We further measured the ability of the bioenergetic modulators (BMs), 2-deoxyglucose, dichloroacetate and phenformin, to modify their metabolic dependence and the therapeutic activity of paclitaxel albumin nanoparticles (NAB-PTX). While all the BMs decreased cell viability and increased cell death in all ECM types, a distinct, collagen I-dependent profile was observed in CSCs. As ECM collagen I content increased (e.g., more aggressive conditions), the CSCs switched from glucose to mostly glutamine metabolism. All three BMs synergistically potentiated the cytotoxicity of NAB-PTX in both cell lines, which, in CSCs, was collagen I-dependent and the strongest when treated with phenformin + NAB-PTX. Metabolic disruption in PDAC can be useful both as monotherapy or combined with conventional drugs to more efficiently block tumor growth.

Targeting the YAP/TAZ mechanotransducers in solid tumour therapeutics.

Targeting the YAP/TAZ mechanotransducers in solid tumour therapeutics.

Abstract 1328: Building a 3D co-culture model for metastatic pancreatic ductal cancer using Curiochips microphysiological system

Abstract Despite the use of multi-agent conventional chemotherapy regimens, metastatic pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal solid tumors with a 5-year survival of 9%. PDAC is characterized by a complex tumor microenvironment with multilayered interplay between neoplastic and stromal cells and the natural extracellular matrix (ECM). To date, models that recapitulate the complexity of these features are only partially reproduced ex vivo and lack the capacity to recreate PDAC tumor microenvironment physiology, fluid flow and the ECM architecture. To address these issues, we developed Curiochips MPS platform for metastatic PDAC on-a-chip. To replicate an accurate PDAC complex tumor microenvironment, we investigated human pancreatic cancer cell lines with/without SMAD4 mutation as a test model. SMAD4 is among the most frequently altered genes in PDAC and its mutation accelerates pancreatic cancer cell migration. To tailor cell-ECM interactions and recreate natural biochemical environment of tumors, we examined various ECM conditions. ECM substitutes such as type I collagen and fibrin gel offer mechanical properties to closely mimic the tumor ECM. We accessed the effect of ECM condition on the pancreatic stellate cells (PSC) activation and pancreatic cancer cell migration using PANC-1 (SMAD4-WT) and BxP3 (SMAD4-null) cell lines. Notably, type I collagen induced more PSC activation than fibrin gel. Interestingly BxP3 spheroids migrated toward to the endothelial compartment compared to PANC-1. Angiogenesis of endothelial cells was more prominent in co-culture with BxP3 than PANC-1. Furthermore, we are building the metastatic model using PDAC patient derived organoids and co-culture with primary PSC in different types of ECM. Preliminary analysis showed functional responses such as 3D organoid migration and aggregation, PSC activation and migration controlled by specific properties of EMC. Our data highlight the importance of the ECM composition on PDAC migration, PSC activation and angiogenesis in the context of genetic heterogeneity and presence/absence oncogenic mutation. The 3D co-culture platform, Curiochips offers suitable and tailored solution to investigate tumor-stroma interaction and potentially can be used as a platform for drug discovery and precision oncology to target PDAC desmoplastic tumor microenvironment. Citation Format: Sumin Kim, Yeongmin Choi, Jihye Baek, Bharti Garg, Jan Pencik, Andrew M. Lowy, Herve Tiriac, Sanghee Yoo. Building a 3D co-culture model for metastatic pancreatic ductal cancer using Curiochips microphysiological system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1328.

Discriminant Principal Component Analysis of ToF-SIMS Spectra for Deciphering Compositional Differences of MSC-Secreted Extracellular Matrices.

Identifying characteristic extracellular matrix (ECM) variants is a key challenge in mechanistic biology, bioengineering, and medical diagnostics. The reported study demonstrates the potential of time-of-flight secondary ion mass spectrometry (ToF-SIMS) to detect subtle differences between human mesenchymal stromal cell (MSC)-secreted ECM types as induced by exogenous stimulation or emerging pathology. ToF-SIMS spectra of decellularized ECM samples are evaluated by discriminant principal component analysis (DPCA), an advanced multivariate analysis technique, to decipher characteristic compositional features. To establish the approach, signatures of major ECM proteins are determined from samples of pre-defined mixtures. Based on that, sets of ECM variants produced by MSCs in vitro are analyzed. Differences in the content of collagen, fibronectin, and laminin in the ECM resulting from the combined supplementation of MSC cultures with polymers that induce macromolecular crowding and with ascorbic acid are detected from the DPCA of ToF-SIMS spectra. The results are verified by immunostaining. Finally, the comparative ToF-SIMS analysis of ECM produced by MSCs of healthy donors and patients suffering from myelodysplastic syndrome display the potential of the novel methodology to reveal disease-associated alterations of the ECM composition.

Impact of hyaluronan size on localization and solubility of the extracellular matrix in the mouse brain.

Hyaluronan (HA) is a central component of the extracellular matrix (ECM) in the brain and plays a pivotal role in neural development and plasticity. Brain HA exists in 2 distinct forms of the ECM: the diffuse ECM, which is soluble in saline and detergents, and the condensed ECM, which forms aggregates, such as perineuronal nets (PNNs). Although the physiological functions of HA significantly differ depending on its size, size differences in HA have not yet been examined in the 2 ECM types, which is partly because of the lack of methods to rapidly and accurately measure the molecular weight (MW) of HA. In this study, we established a simple method to simultaneously assess the MW of HA in multiple crude biological samples. HA was purified through single-step precipitation from tissue extracts using biotinylated HA-binding protein and streptavidin-coupled magnetic beads, followed by separation on gel electrophoresis. By applying this method to HA in the mouse brain, we revealed that the condensed ECM contained higher MW HA than the diffuse ECM. Higher MW HA and lower MW HA exhibited different spatial distributions: the former was confined to PNNs, whereas the latter was widely present throughout the brain. Furthermore, the limited degradation of HA showed that only higher MW HA was required to form an insoluble HA-aggrecan complex. The present study demonstrated that the MW of HA in the brain strongly correlates with the localization and solubility of the ECM it forms.

Genetic Disorders of the Extracellular Matrix: From Cell and Gene Therapy to Future Applications in Regenerative Medicine.

Metazoans have evolved to produce various types of extracellular matrix (ECM) that provide structural support, cell adhesion, cell-cell communication, and regulated exposure to external cues. Epithelial cells produce and adhere to a specialized sheet-like ECM, the basement membrane, that is critical for cellular homeostasis and tissue integrity. Mesenchymal cells, such as chondrocytes in cartilaginous tissues and keratocytes in the corneal stroma, produce a pericellular matrix that presents optimal levels of growth factors, cytokines, chemokines, and nutrients to the cell and regulates mechanosensory signals through specific cytoskeletal and cell surface receptor interactions. Here, we discuss laminins, collagen types IV and VII, and perlecan, which are major components of these two types of ECM. We examinegenetic defects in these components that cause basement membrane pathologies such as epidermolysis bullosa, Alport syndrome, rare pericellular matrix-related chondrodysplasias, and corneal keratoconus and discuss recent advances in cell and gene therapies being developed for some of these disorders.

Investigating the Effects of IRF6 on Focal Adhesions in Keratinocytes

Focal adhesions are one of the two main types of adhesions between cells and the extra‐cellular matrix (ECM). Focal adhesions are dynamic complexes anchored to the actin cytoskeleton through intracellular adaptor proteins, and to the ECM through heterodimers of α and β integrins, forming a transmembrane link between the intra‐ and extra‐cellular space. β‐1 integrin is the primary β subunit found in keratinocytes, and its corresponding heterodimers show affinity for a wide range of ECM proteins including collagen, fibronectin, and laminin. Collagen is the main structural protein in cutaneous ECM (the dermis), while fibronectin is a glycoprotein found in the ECM that binds integrins and plays a crucial role in wound healing. Interferon regulatory factor 6 (IRF6) is a transcription factor expressed by epithelial cells that regulates keratinocyte differentiation, cell‐cell adhesions, and migration. It is well known that focal adhesions are required for cell migration, however the role of IRF6 in regulating focal adhesions is unknown. Therefore, we hypothesize that IRF6 regulates focal adhesion formation. To determine if IRF6 levels affect attachment to the ECM, we seeded wildtype and IRF6 knockdown keratinocytes on collagen IV and plastic and quantified the number of cells attached to the plate after thirty and sixty minutes. No differences were found between wild‐type and IRF6 knockdown keratinocytes on plastic. However, less IRF6 knockdown keratinocytes were attached on collagen IV compared to wildtypes. To explore how IRF6 affects focal adhesions, we plated IRF6 knockdown and wild‐type keratinocytes on different types of ECM that were representative of both normal and wounded conditions of the dermis. Immunofluorescent staining for β‐1 integrin and phalloidin was performed, followed by quantitative analysis of focal adhesion length and intensity. Initial observations indicate that IRF6 knockdown keratinocytes consistently have longer focal adhesions compared to the wildtype. Variations of β‐1 fluorescent intensity was also observed in wild‐type cells compared to IRF6 knockdown keratinocytes. These preliminary results suggest a role for IRF6 in regulating focal adhesions, providing a potential mechanism for the underlying defect observed in the migration of IRF6 deficient keratinocytes.

Extracellular Matrix Optimization for Enhanced Physiological Relevance in Hepatic Tissue-Chips.

The cellular microenvironment is influenced explicitly by the extracellular matrix (ECM), the main tissue support biomaterial, as a decisive factor for tissue growth patterns. The recent emergence of hepatic microphysiological systems (MPS) provide the basic physiological emulation of the human liver for drug screening. However, engineering microfluidic devices with standardized surface coatings of ECM may improve MPS-based organ-specific emulation for improved drug screening. The influence of surface coatings of different ECM types on tissue development needs to be optimized. Additionally, an intensity-based image processing tool and transepithelial electrical resistance (TEER) sensor may assist in the analysis of tissue formation capacity under the influence of different ECM types. The current study highlights the role of ECM coatings for improved tissue formation, implying the additional role of image processing and TEER sensors. We studied hepatic tissue formation under the influence of multiple concentrations of Matrigel, collagen, fibronectin, and poly-L-lysine. Based on experimental data, a mathematical model was developed, and ECM concentrations were validated for better tissue development. TEER sensor and image processing data were used to evaluate the development of a hepatic MPS for human liver physiology modeling. Image analysis data for tissue formation was further strengthened by metabolic quantification of albumin, urea, and cytochrome P450. Standardized ECM type for MPS may improve clinical relevance for modeling hepatic tissue microenvironment, and image processing possibly enhance the tissue analysis of the MPS.

The hippo pathway orchestrates cytoskeletal organisation during intervertebral disc degeneration

Yes-associated protein (YAP) activity responded to physical and mechanical cues such as extracellular matrix (ECM), cell density and the mechanical regulation of YAP controlled cellular proliferation and inhibition of apoptotic signals. The intervertebral disc (IVD) comprises a heterogeneous population of cells, including those of the nucleus pulposus (NP) and annulus fibrosus (AF), which are diverse in phenotype, partly due to the different ECM and mechanical loads they experience. How do IVD cells sense microenvironment and what is the relationship between YAP and cytoskeleton in the process of intervertebral disc degeneration (IDD) are not well understood. First, Hippo pathway and cytoskeleton organisation were assessed in the NP and AF of immature (4 weeks), mature (14 weeks), aged (50 weeks), and degenerated (14 weeks, 4 weeks after annulus puncture) IVDs. Second, to assess the effect of ECM composition and cell density on cytoskeleton and YAP levels, we seeded cells at different densities on three types of ECM. In this study, YAP and F-actin activity decreased gradually with age in natural IDD. Hippo signalling was suppressed in the early stages of disc injury, demonstrating the potential for endogenous repair, but this repair did not prevent further disc degeneration. β-tubulin and vimentin filaments provide the cell with its shape and its elastic properties in resisting mechanical forces. The Hippo pathway and cytoskeleton were shown to be regulated by cell density and the ECM composition.

Evaluating the Effect of Tissue Selection on the Characteristics of Extracellular Matrix Hydrogels from Decellularized Porcine Bladders

Porcine urinary bladder is one of the most used organs to fabricate extracellular matrix (ECM) hydrogel. Although there are two different ECM types inside a bladder, i.e., urinary bladder matrix (UBM) and a subtype ECM (sECM), most studies have only employed UBM for hydrogel fabrication, and overlooked the potential use of sECM. In another aspect, the delamination of UBM from bladders is a time-consuming process; consequently, the use of the whole bladder (WB) will likely increase production yield. Therefore, the objective of this study was to fabricate hydrogels from sECM and WB and compare them to UBM. The results indicated that different layers of the bladder shared almost the same biochemical composition. In terms of gelation kinetics, rheology and morphology, although hydrogels from UBM and sECM exhibited some discrepancies, those from UBM and WB interestingly possessed almost the same characteristics. In in vitro studies, all the hydrogels possessed nearly the same biochemical effects towards L929 viability and C2C12 differentiation. These results could preliminarily indicate that the use of sECM should no longer be ignored, and WB could be a promising substitution for UBM hydrogels, eliminating the need for time-consuming delamination processes, as well as increasing the possibility of mass production.

Extracellular Matrix in Neural Plasticity and Regeneration.

The extracellular matrix (ECM) is a fundamental component of biological tissues. The ECM in the central nervous system (CNS) is unique in both composition and function. Functions such as learning, memory, synaptogenesis, and plasticity are regulated by numerous ECM molecules. The neural ECM acts as a non-specific physical barrier that modulates neuronal plasticity and axon regeneration. There are two specialized types of ECM in the CNS, diffuse perisynaptic ECM and condensed ECM, which selectively surround the perikaryon and initial part of dendritic trees in subtypes of neurons, forming perineuronal nets. This review presents the current knowledge about the role of important neuronal ECM molecules in maintaining the basic functions of a neuron, including electrogenesis and the ability to form neural circuits. The review mainly focuses on the role of ECM components that participate in the control of key events such as cell survival, axonal growth, and synaptic remodeling. Particular attention is drawn to the numerous molecular partners of the main ECM components. These regulatory molecules are integrated into the cell membrane or disposed into the matrix itself in solid or soluble form. The interaction of the main matrix components with molecular partners seems essential in molecular mechanisms controlling neuronal functions. Special attention is paid to the chondroitin sulfate proteoglycan 4, type 1 transmembrane protein, neural-glial antigen 2 (NG2/CSPG4), whose cleaved extracellular domain is such a molecular partner that it not only acts directly on neural and vascular cells, but also exerts its influence indirectly by binding to resident ECM molecules.

The Bone Extracellular Matrix in Bone Formation and Regeneration.

Bone regeneration repairs bone tissue lost due to trauma, fractures, and tumors, or absent due to congenital disorders. The extracellular matrix (ECM) is an intricate dynamic bio-environment with precisely regulated mechanical and biochemical properties. In bone, ECMs are involved in regulating cell adhesion, proliferation, and responses to growth factors, differentiation, and ultimately, the functional characteristics of the mature bone. Bone ECM can induce the production of new bone by osteoblast-lineage cells, such as MSCs, osteoblasts, and osteocytes and the absorption of bone by osteoclasts. With the rapid development of bone regenerative medicine, the osteoinductive, osteoconductive, and osteogenic potential of ECM-based scaffolds has attracted increasing attention. ECM-based scaffolds for bone tissue engineering can be divided into two types, that is, ECM-modified biomaterial scaffold and decellularized ECM scaffold. Tissue engineering strategies that utilize the functional ECM are superior at guiding the formation of specific tissues at the implantation site. In this review, we provide an overview of the function of various types of bone ECMs in bone tissue and their regulation roles in the behaviors of osteoblast-lineage cells and osteoclasts. We also summarize the application of bone ECM in bone repair and regeneration. A better understanding of the role of bone ECM in guiding cellular behavior and tissue function is essential for its future applications in bone repair and regenerative medicine.

The extracellular matrix in development.

ABSTRACTAs the crucial non-cellular component of tissues, the extracellular matrix (ECM) provides both physical support and signaling regulation to cells. Some ECM molecules provide a fibrillar environment around cells, while others provide a sheet-like basement membrane scaffold beneath epithelial cells. In this Review, we focus on recent studies investigating the mechanical, biophysical and signaling cues provided to developing tissues by different types of ECM in a variety of developing organisms. In addition, we discuss how the ECM helps to regulate tissue morphology during embryonic development by governing key elements of cell shape, adhesion, migration and differentiation.

Extracellular matrix type modulates mechanotransduction of stem cells

Extracellular matrix (ECM) is comprised of different types of proteins, which change in composition and ratios during morphogenesis and disease progression. ECM proteins provide cell adhesion and impart mechanical cues to the cells. Increasing substrate stiffness has been shown to induce Yes-associated protein (YAP) translocation from the cytoplasm to the nucleus, yet these mechanistic studies used fibronectin only as the biochemical cue. How varying the types of ECM modulates mechanotransduction of stem cells remains largely unknown. Using polyacrylamide hydrogels with tunable stiffness as substrates, here we conjugated four major ECM proteins commonly used for cell adhesion: fibronectin, collagen I, collagen IV and laminin, and assessed the effects of varying ECM type and density on YAP translocation in human mesenchymal stem cells (hMSCs). For all four ECM types, increasing ECM ligand density alone can induce YAP nuclear translocation without changing substrate stiffness. The ligand threshold for such biochemical ligand-induced YAP translocation differs across ECM types. While stiffness-dependent YAP translocation can be induced by all four ECM types, each ECM requires a different optimized ligand density for this to occur. Using antibody blocking, we further identified integrin subunits specifically involved in mechanotransduction of different ECM types. Finally, we demonstrated that altering ECM type further modulates hMSC osteogenesis without changing substrate stiffness. These findings highlight the important role of ECM type in modulating mechanotransduction and differentiation of stem cells, and call for future mechanistic studies to further elucidate the role of changes in ECM compositions in mediating mechanotransduction during morphogenesis and disease progression. STATEMENT OF SIGNIFICANCE: Our study addresses a critical gap of knowledge in mechanobiology. Increasing substrate stiffness has been shown to induce nuclear YAP translocation, yet only on fibronectin-coated substrates. However, extracellular matrix (ECM) is comprised of different protein types. How varying the type of ECM modulates stem cell mechanotransduction remains largely unknown. We here reveal that the choice of ECM type can directly modulate stem cell mechanotransduction, filling this critical gap. This work has broad impacts in mechanobiology and biomaterials, as it provides the first evidence that varying ECM type can impact YAP translocation independent of substrate stiffness, opening doors for a more rational biomaterials design tuning ECM properties to control cell fate for promoting normal development and for preventing disease progression.

Extracellular matrix derived by human umbilical cord-deposited mesenchymal stem cells accelerates chondrocyte proliferation and differentiation potential in vitro.

The extracellular matrix (ECM) is a dynamic and intricate three-dimensional (3D) microenvironment with excellent biophysical, biomechanical, and biochemical properties that may directly or indirectly regulate cell behavior, including proliferation, adhesion, migration, and differentiation. Compared with tissue-derived ECM, cell-derived ECM potentially has more advantages, including less potential for pathogen transfer, fewer inflammatory or anti-host immune responses, and a closer resemblance to the native ECM microenvironment. Different types of cell-derived ECM, such as adipose stem cells, synovium-derived stem cells and bone marrow stromal cells, their effects on articular chondrocytes which have been researched. In this study, we aimed to develop a 3D cell culture substrate using decellularized ECM derived from human umbilical cord-derived mesenchymal stem cells (hUCMSCs), and evaluated the effects on articular chondrocytes. We evaluated the morphology and components of hUCMSC-derived ECM using physical and chemical methods. Morphological, histological, immunohistochemical, biochemical, and real-time PCR analyses demonstrated that proliferation and differentiation capacity of chondrocytes using the 3D hUCMSC-derived ECM culture substrate was superior to that using non-coated two-dimensional plastic culture plates. In conclusion, 3D decellularized ECM derived from hUCMSCs offers a tissue-specific microenvironment for in vitro culture of chondrocytes, which not only markedly promoted chondrocyte proliferation but also preserved the differentiation capacity of chondrocytes. Therefore, our findings suggest that a 3D cell-derived ECM microenvironment represents a promising prospect for autologous chondrocyte-based cartilage tissue engineering and regeneration. The hUCMSC-derived ECM as a biomaterial is used for the preparation of scaffold or hybrid scaffold products which need to further study in the future.

Polydopamine-Based Interfacial Engineering of Extracellular Matrix Hydrogels for the Construction and Long-Term Maintenance of Living Three-Dimensional Tissues.

Diverse biological processes in the body rely on the ability of cells to exert contractile forces on their extracellular matrix (ECM). In three-dimensional (3D) cell culture, however, this intrinsic cellular property can cause unregulated contraction of ECM hydrogel scaffolds, leading to a loss of surface anchorage and the resultant structural failure of in vitro tissue constructs. Despite advances in the 3D culture technology, this issue remains a significant challenge in the development and long-term maintenance of physiological 3D in vitro models. Here, we present a simple yet highly effective and accessible solution to this problem. We leveraged a single-step surface functionalization technique based on polydopamine to drastically increase the strength of adhesion between hydrogel scaffolds and cell culture substrates. Our method is compatible with different types of ECM and polymeric surfaces and also permits prolonged shelf storage of functionalized culture substrates. The proof-of-principle of this technique was demonstrated by the stable long-term (1 month) 3D culture of human lung fibroblasts. Furthermore, we showed the robustness and advanced application of the method by constructing a dynamic cell stretching system and performing over 100 000 cycles of mechanical loading on 3D multicellular constructs for visualization and quantitative analysis of stretch-induced tissue alignment. Finally, we demonstrated the potential of our technique for the development of microphysiological in vitro models by establishing microfluidic 3D co-culture of vascular endothelial cells and fibroblasts to engineer self-assembled, perfusable 3D microvascular beds.