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The extracellular matrix (ECM) offers the opportunity to create a biomaterial consisting of a microenvironment with interesting biological and biophysical properties for improving and regulating cell functions. Animal-derived ECM are the most widely used as an alternative to human tissues that are of very limited availability. However, incomplete decellularization of these tissues presents a high risk of immune rejection and disease transmission. In this study, we present an innovative method to extract human ECM derived from the Wharton's jelly (WJ-ECMaa) of umbilical cords as a novel biomaterial to be used in tissue engineering. WJ-ECMaa was very efficiently decellularized, suggesting its possible use in allogeneic conditions. Characterization of its content allowed the identification of type I collagen as its main component. Various other matrix proteins, playing an important role in cell adhesion and proliferation, were also detected. WJ-ECMaa applied as a surface coating was analyzed by fluorescent labeling and atomic force microscopy. The results revealed a particular arrangement of collagen fibers not previously described in the literature. This biomaterial also presented better cytocompatibility compared to the conventional collagen coating. Moreover, it showed adequate hemocompatibility, allowing its use as a surface with direct contact with blood. Application of WJ-ECMaa as a coating of the luminal surface of umbilical arteries for a use in vascular tissue engineering, has improved significantly the cellularization of this surface by allowing a full and homogeneous cell coverage. Taking these results together, our novel extraction method of human ECM offers a very promising biomaterial with many potential applications in tissue engineering such as the one presented direct in vascular tissue engineering. Further characterization of the composition and functionality will help explore the ways it can be used in tissue engineering applications, especially as a scaffold or a surface coating.
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Due to the lack of efficacy of synthetic vascular substitutes in the replacement of small-caliber arteries, vascular tissue engineering (VTE) has emerged as a promising solution to produce viable small-caliber tissue-engineered vascular grafts (TEVG). Previous studies have shown the importance of a cellular intimal layer at the luminal surface of TEVG to prevent thrombotic events. However, the cellularization of a TEVG seems to be a critical approach to consider in the development of a TEVG. To date, no standard cellularization method or cell type has been established to create the ideal TEVG by promoting its long-term patency and function. In this review, advances in VTE are described and discussed with a particular focus on the construction approaches of cellularized small-caliber TEVGs, the cell types used, as well as their preclinical and clinical applications.
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OBJECTIVE: The aim of this study is to investigate the changes of human dental pulp stem cell (hDPSC) viability, proliferation and osteogenic differentiation in high glucose condition. DESIGN: After 21 days of culture in low (5.5â¯mM) and high (20â¯mM) glucose medium, hDPSC viability and proliferation were assessed with respectively the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Hoechst assays. To investigate the influence of glucose on osteogenic differentiation hDPSCs were cultured for 28 days in low or high glucose medium with osteoinductive cocktail. Mineralization was examined by alizarin red staining/quantification and the expression of osteogenic-related genes [Runt-related transcription factor 2 (RUNX2), Osteocalcin (OCN), Collagen 1A1 (COL1A1)] analyzed by RT-qPCR. RESULTS: We observed no significant difference (pâ¯>⯠0.05) on hDPSC proliferation or cell viability between low or high glucose groups. We did not highlight a significant difference after alizarin red staining and quantification between hDPSCs cultured with high or low glucose concentration in the culture medium. In the same manner, high glucose concentration did not appear to modify osteogenic gene expression: there was no significant difference in osteogenic-related gene expression between high or low glucose groups. CONCLUSION: Proliferation, viability, and osteogenic differentiation of hDPSCs were not changed by high glucose environment.
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Proliferação de Células , Polpa Dentária/citologia , Glucose , Osteogênese , Células-Tronco/citologia , Diferenciação Celular , Células Cultivadas , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Meios de Cultura , Humanos , Osteocalcina/metabolismoRESUMO
The most important prerequisites for wound coverage matrices are biocompatibility, adequate porosity, degradability and exudate uptake capacity. A moderate hydrophilicity and exudate uptake capacity can often favour cell adhesion and wound healing potential, however, most of the synthetic polymers like polycaprolactone (PCL) are hydrophobic. Hydrogels based on natural polymers can improve the hydrophilicity and exudate uptake capacity of synthetic dressings and improve healing. In this work, we report the development of chitosan ascorbate-infiltrated electrospun PCL membranes. Our study demonstrated that chitosan ascorbate infiltration improves the hydrophilicity as well as water uptake capacity of the membranes and highly favoured the adhesion of human umbilical vein endothelial cells and human mesenchymal stem cells on the membranes.
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Ácido Ascórbico/química , Adesão Celular/efeitos dos fármacos , Quitosana/química , Hidrogéis/química , Membranas/efeitos dos fármacos , Poliésteres/química , Água/química , Linhagem Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/química , Polímeros/química , Porosidade , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Cicatrização/efeitos dos fármacosRESUMO
Musculoskeletal pathologies, especially those affecting bones and joints, remain a challenge for regenerative medicine. The main difficulties affecting bone tissue engineering are the size of the defects, the need for blood vessels and the synthesis of appropriate matrix elements in the engineered tissue. Indeed, the cartilage is an avascular tissue and consequently has limited regenerative abilities. Thanks to their self-renewal, plasticity and immunomodulatory properties, mesenchymal stem cells (MSCs) became a central player in tissue engineering, and have already been shown to be able to differentiate towards chondrogenic or osteogenic phenotypes. Whether synthetic (e.g. tricalcium phosphate) or from natural sources (e.g. hyaluronic acid), biomaterials can be shaped to fit into bone and cartilage defects to ensure mechanical resistance and may also be designed to control cell spatial distribution or differentiation. Soluble factors are classically used to promote cell differentiation and to stimulate extracellular matrix synthesis to achieve the desired tissue production. But as they have a limited lifetime, transfection using plasmid DNA or transduction via a viral vector of therapeutic genes to induce the cell secretion of these factors allows to have more lasting effects. Also, the chondrocyte phenotype may be difficult to control over time, with for example the production of hypertrophic or osteogenic markers that is undesirable in hyaline cartilage. Thus, tissue regeneration strategies became more elaborate, with an attempt at associating the benefits of MSCs, biomaterials, and gene therapy to achieve a proper tissue repair. This minireview focuses on in vitro and in vivo studies combining biomaterials and gene therapy associated with MSCs for bone and cartilage engineering.
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Materiais Biocompatíveis , Terapia Genética , Células-Tronco Mesenquimais/fisiologia , Doenças Musculoesqueléticas/terapia , Medicina Regenerativa/métodos , Animais , Regeneração Óssea , Diferenciação Celular , Condrogênese , Vetores Genéticos , Humanos , Transplante de Células-Tronco Mesenquimais , Osteogênese , Engenharia Tecidual , Alicerces TeciduaisRESUMO
Mesenchymal stem cells (MSC) have a lot of potential in regenerative medicine, and MSC-based therapies are currently explored in numerous research fields. Among these cells, deciduous or permanent dental pulp-MSC represent a promising option in tissue engineering. This expectation is based on their capacity to self-renew, to repair various damaged tissues and organs due to their multipotency, as well as their ability to modulate immune system. They present other advantages such as the harvesting by a simple, painless, and noninvasive procedure and the absence of ethical considerations. The role played by these cells in the reparative process is mainly attributed to paracrine mechanisms mediated by their secreted factors, namely the secretome. The secreted factors can be found in the cell culture medium, called conditioned medium (CM). Moreover, CM presents many advantages compared with cells such as possible use in allogeneic therapies. This minireview aims at investigating the therapeutic use of dental pulp MSC-derived CM to develop cell-free therapies. The analysis of the available literature illustrates its massive panel of potential applications: mainly reduction of inflammation, promotion of angiogenesis and neurogenesis, reduction of stroke or ischemia, and organ regeneration. Furthermore, studies often highlight its superiority over the other sources of CM derived from other stem cells for the same applications. Dental pulp MSC-derived CM is an attractive, noninvasive, and acellular tool for therapeutic approaches in regenerative medicine. This promising novel approach should be further explored for clinical applications.
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Meios de Cultivo Condicionados/metabolismo , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Regeneração , Medicina Regenerativa , Engenharia Tecidual/métodos , Animais , Polpa Dentária/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismoRESUMO
Next-generation tissue engineering exploits the body's own regenerative capacity by providing an optimal niche via a scaffold for the migration and subsequent proliferation of endogenous cells to the site of injury, enhancing regeneration and healing and bypassing laborious in vitro cell-culturing procedures. Such systems are also required to have a sufficient angiogenic capacity for the subsequent patency of implanted scaffolds. The exploitation of redox properties of nanodimensional ceria (nCeO2) in in situ tissue engineering to promote cell adhesion and angiogenesis is poorly investigated. As a novel strategy, electrospun polycaprolactone based tissue-engineering scaffolds loaded with nCeO2 were developed and evaluated for morphological and physicomechanical features. In addition, in vitro and in vivo studies were performed to show the ability of nCeO2-containing scaffolds to enhance cell adhesion and angiogenesis. These studies confirmed that nCeO2-containing scaffolds supported cell adhesion and angiogenesis better than bare scaffolds. Gene-expression studies had shown that angiogenesis-related factors such as HIF1α and VEGF were up-regulated. Overall results show that incorporation of nCeO2 plays a key role in scaffolds for the enhancement of angiogenesis, cell adhesion, and cell proliferation and can produce a successful outcome in in situ tissue engineering.
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BACKGROUND: Human tissue derived natural extracellular matrix (ECM) has great potential in tissue engineering. OBJECTIVE: We sought to isolate extracellular matrix derived from human umbilical cord and test its potential in tissue engineering. METHODS: An enzymatic method was applied to isolate and solubilized complete human umbilical cord derived matrix (hUCM). The obtained solution was analyzed for growth factors, collagen and residual DNA contents, then used to coat 2D and 3D surfaces for cell culture application. RESULTS: The hUCM was successfully isolated with trypsin digestion to acquire a solution containing various growth factors and collagen but no residual DNA. This hUCM solution can form a coating on 2D and 3D substrates suitable cell culture. CONCLUSION: We developed a new matrix derived from human source that can be further used in tissue engineering.
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Matriz Extracelular/química , Células Endoteliais da Veia Umbilical Humana/citologia , Células-Tronco Mesenquimais/citologia , Alicerces Teciduais/química , Cordão Umbilical/química , Materiais Biocompatíveis/química , Adesão Celular , Técnicas de Cultura de Células/métodos , Proliferação de Células , Células Cultivadas , Colágeno/análise , DNA/análise , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/análise , Engenharia Tecidual/métodosRESUMO
Mesenchymal stem cells (MSCs) are widely used in cell therapy and tissue engineering thanks to their self-renewal, their multipotency, and their immunomodulatory properties that make them an attractive tool for regenerative medicine. A large part of MSCs positive effects is due to their secretion products which participate in creating a favorable microenvironment and closely relate these cells to other cell types. Extracellular vesicles (EVs) belong to cellular secretions. They are produced by cells continuously or after stimulation (e.g., calcium flux, cellular stress) and act in tissue homeostasis and intercellular communication. The understanding of the role of EVs is growing, more particularly their impact on cell migration, differentiation, or immunomodulation. EVs derived from MSCs show these interesting properties that may be considered in therapeutics, although they can have adverse effects by facilitating cancer propagation. Moreover, MSC behavior may also be influenced (proliferation, differentiation) by EVs derived from other donor cells. The aim of this mini review is to summarize the two-way communication between MSCs and other cell types, and how they can affect each other with their microenvironment through EVs. On the one hand, the manuscript presents the influence of MSC-derived EVs on diverse recipient cells and on the other hand, the effects of EVs derived from various donor cells on MSCs. The discrepancies between cancer cells and MSCs communication according to the sources of MSCs but also the tumor origins are also mentioned.
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One of the outstanding goals in tissue engineering is to develop a natural coating surface which is easy to manipulate, effective for cell adhesion and fully biocompatible. The ideal surface would be derived from human tissue, perfectly controllable, and pathogen-free, thereby satisfying all of the standards of the health authorities. This paper reports an innovative approach to coating surfaces using a natural extracellular matrix (ECM) extracted from the Wharton's jelly (WJ) of the umbilical cord (referred to as WJ-ECM). We have shown by atomic force microscopy (AFM), that the deposition of WJ-ECM on surfaces is homogenous with a controllable thickness, and that this easily-prepared coating is appropriate for both the adhesion and proliferation of human mesenchymal stem cells and mature endothelial cells. Furthermore, under physiological shear stress conditions, a larger number of cells remained adhered to WJ-ECM than to a conventional coating such as collagen - a result supported by the higher expression of both integrins α2 and ß1 in cells cultured on WJ-ECM. Our data clearly show that Wharton's jelly is a highly promising coating for the design of human biocompatible surfaces in tissue engineering as well as in regenerative medicine. STATEMENT OF SIGNIFICANCE: Discovery and design of biomaterial surface are a hot spot in the tissue engineering field. Natural matrix is preferred to mimic native cell microenvironment but its use is limited due to poor resource availability. Moreover, current studies often use single or several components of natural polymers, which is not the case in human body. This paper reports a natural extracellular matrix with full components derived from healthy human tissue: Wharton's jelly of umbilical cord. Reconstituting this matrix as a culture surface, our easily-prepared coating provides superior biocompatibility for stem and mature cells. Furthermore, we observed improved cell performance on this coating under both static and dynamic condition. This novel human derived ECM would be a promising choice for regenerative medicine.
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Vasos Sanguíneos/fisiologia , Materiais Revestidos Biocompatíveis/farmacologia , Matriz Extracelular/metabolismo , Engenharia Tecidual/métodos , Geleia de Wharton/metabolismo , Vasos Sanguíneos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Módulo de Elasticidade , Matriz Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Estresse MecânicoRESUMO
Designing convenient substrates is a pertinent parameter that can guide stem cell differentiation. Current research is directed toward differentiating mesenchymal stem cells (MSCs) into endothelial cells (ECs). It is generally accepted that MSCs cannot be easily differentiated into ECs without high concentrations of proangiogenic factors. To guide either bone marrow-derived mesenchymal stem cells (BM-MSCs) and Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) into ECs-like phenotype, poly(allylamine-hydrochloride)/poly(styrene-sulfonate) multilayers film (PAH/PSS) was used as culture coating and compared to type I collagen (as control coating). After 2 weeks of culture and in absence of angiogenic growth factors, PAH/PSS upregulated KDR, PECAM-1, and CDH5 genes, whereas combining PAH/PSS with endothelial growth media (EGM-2® ) led to the production of respective proteins by WJ-MSCs. In contrast, not fully EC-like phenotype is obtained from the differentiation of BM- or WJ-MSCs cultured on type I collagen. Thus, using PAH/PSS coating in synergy with EGM-2® appears as an ideal condition promoting WJ-MSCs differentiation into ECs-like. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 292-300, 2017.
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Antígenos de Diferenciação/sangue , Células Endoteliais/metabolismo , Células-Tronco Mesenquimais/metabolismo , Polieletrólitos , Regulação para Cima/efeitos dos fármacos , Técnicas de Cultura de Células , Células Endoteliais/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Polieletrólitos/química , Polieletrólitos/farmacologiaRESUMO
Wharton's jelly mesenchymal stromal cells (WJ-MSCs) are promising candidates for tissue engineering, as their immunomodulatory activity allows them to escape immune recognition and to suppress several immune cell functions. To date, however, few studies have investigated the effect of differentiation of the MSCs on this immunomodulation. To address this question, we sought to determine the impact of differentiation toward endothelial cells on immunoregulation by WJ-MSCs. Following differentiation, the endothelial-like cells (ELCs) were positive for CD31, vascular endothelial cadherin and vascular endothelial growth factor receptor 2, and able to take up acetylated low-density lipoproteins. The expression of HLA-DR and CD86, which contribute to MSCs immunoprivilege, was still weak after differentiation. We then co-cultured un- and differentiated MSCs with immune cells, under conditions of both direct and indirect contact. The proliferation and phenotype of the immune cells were analyzed and the mediators secreted by both ELCs and WJ-MSCs quantified. Interleukin (IL)-6, IL-1ß, prostaglandin E2 and in particular indoleamine-2,3-dioxygenase expression were upregulated in ELCs on stimulation by T and NK cells, suggesting the possible involvement of these factors in allosuppression. ELCs co-cultured with T cells were able to generate CD25(+) T cells, which were shown to be of the CD4(+)CD25(+)FoxP3(+) regulatory subset. Direct contact between NK cells and ELCs or WJ-MSCs decreased the level of NK-activating receptor natural-killer group 2, member D. Moreover, direct co-culturing with ELCs stimulates CD73 acquisition on NK cells, a mechanism which may induce adenosine secretion by the cells and lead to an immunosuppressive function. Taken together, our results show that ELCs obtained following differentiation of WJ-MSCs remain largely immunosuppressive.
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Células Endoteliais/fisiologia , Células Matadoras Naturais/fisiologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Linfócitos T Reguladores/fisiologia , 5'-Nucleotidase/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Terapia de Imunossupressão , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismoRESUMO
Mesenchymal stem cells (MSCs) are among the most promising and suitable stem cell types for vascular tissue engineering. Substantial effort has been made to differentiate MSCs towards vascular cell phenotypes, including endothelial cells and smooth muscle cells (SMCs). The microenvironment of vascular cells not only contains biochemical factors that influence differentiation, but also exerts hemodynamic forces, such as shear stress and cyclic strain. Recent evidence has shown that these forces can influence the differentiation of MSCs into endothelial cells or SMCs. In this Commentary, we present the main findings in the area with the aim of summarizing the mechanisms by which shear stress and cyclic strain induce MSC differentiation. We will also discuss the interactions between these mechanical cues and other components of the microenvironment, and highlight how these insights could be used to maintain differentiation.
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Diferenciação Celular/fisiologia , Células Endoteliais/metabolismo , Mecanotransdução Celular/fisiologia , Células-Tronco Mesenquimais/metabolismo , Miócitos de Músculo Liso/metabolismo , Neovascularização Fisiológica/fisiologia , Animais , Células Endoteliais/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Miócitos de Músculo Liso/citologia , Nicho de Células-Tronco/fisiologiaRESUMO
Hemoglobin-based oxygen carriers (HBOCs) may generate oxidative stress, vasoconstriction and inflammation. To reduce these undesirable vasoactive properties, we increased hemoglobin (Hb) molecular size by genetic engineering with octameric Hb, recombinant (r) HbßG83C. We investigate the potential side effects of rHbßG83C on endothelial cells. The rHbßG83C has no impact on cell viability, and induces a huge repression of endothelial nitric oxide synthase gene transcription, a marker of vasomotion. No induction of Intermolecular-Adhesion Molecule 1 and E-selectin (inflammatory markers) transcription was seen. In the presence of rHbßG83C, the transcription of heme oxygenase-1 (oxidative stress marker) is weakly increased compared to the two other HBOCs (references) or Voluven (control). This genetically engineered octameric Hb, based on a human Hb ßG83C mutant, leads to little impact at the level of endothelial cell inflammatory response and thus appears as an interesting molecule for HBOC development.
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Substitutos Sanguíneos/farmacologia , Hemoglobinas/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Biomarcadores , Substitutos Sanguíneos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Dextranos/farmacologia , Dextranos/toxicidade , Regulação para Baixo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Selectina E/biossíntese , Selectina E/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/biossíntese , Heme Oxigenase-1/genética , Hemoglobinas/análise , Hemoglobinas/química , Hemoglobinas/toxicidade , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Derivados de Hidroxietil Amido/farmacologia , Derivados de Hidroxietil Amido/toxicidade , Inflamação/induzido quimicamente , Molécula 1 de Adesão Intercelular/biossíntese , Molécula 1 de Adesão Intercelular/genética , Metemoglobina/análise , Modelos Moleculares , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/genética , Estresse Oxidativo/efeitos dos fármacos , Substitutos do Plasma/farmacologia , Substitutos do Plasma/toxicidade , Conformação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Vasoconstrição/efeitos dos fármacosRESUMO
The rising and diversity of many human vascular diseases pose urgent needs for the development of novel therapeutics. Stem cell therapy represents a challenge in the medicine of the twenty-first century, an area where tissue engineering and regenerative medicine gather to provide promising treatments for a wide variety of diseases. Indeed, with their extensive regeneration potential and functional multilineage differentiation capacity, stem cells are now highlighted as promising cell sources for regenerative medicine. Their multilineage differentiation involves environmental factors such as biochemical, extracellular matrix coating, oxygen tension, and mechanical forces. In this review, we will focus on human stem cell sources and their applications in vascular regeneration. We will also discuss the different strategies used for their differentiation into both mature and functional smooth muscle and endothelial cells.
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Neovascularização Fisiológica , Medicina Regenerativa/métodos , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Animais , Humanos , Células-Tronco/classificação , Células-Tronco/metabolismoRESUMO
The choice of volume expander for fluid resuscitation in hemorrhagic shock is still debated. Changes in plasma viscosity (PV) are barely investigated while PV modulates functional capillary density, microcirculation and organ function. The present study evaluated the impact of 2 strategies of fluid resuscitation in hemorrhagic shock in pigs. Ten pigs were subjected to hemorrhagic shock and randomly assigned to a low viscosity fluid regimen (Lactated Ringer's, LR) group or a high viscosity regimen (hypertonic-hydroxyethyl starch, HES) for volume resuscitation. Sublingual microcirculatory flow and tissue oxygen tension were assessed together with macro- and microcirculatory, biochemical and rheological variables at baseline, 30 minutes after hemorrhagic shock, immediately after reaching resuscitation endpoints (R-0), and 60 minutes after resuscitation (R-60). PV decreased similarly in both groups following resuscitation (from 1.36 [1.32-1.38] to 1.21 [1.21-1.23] for LR, and from 1.32 [1.31-1.32] to 1.20 [1.17-1.21] mPa.s for HES). No differences were found between the groups for other rheological variables, microcirculatory flow or tissue oxygen tension at R-0 and R-60. Despite a 6-fold difference in the volumes required to achieve blood flow endpoints, commercially available volume expanders had similar effects on rheological and microcirculatory variables, irrespective of their viscosity. Our findings are consistent with the absence of clinically relevant differences between crystalloid and colloid resuscitation of hemorrhagic shock.
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Hidratação/métodos , Derivados de Hidroxietil Amido/farmacologia , Soluções Isotônicas/farmacologia , Choque Hemorrágico/terapia , Animais , Hemorreologia , Volume Plaquetário Médio , Microcirculação , Distribuição Aleatória , Lactato de Ringer , Choque Hemorrágico/sangue , SuínosRESUMO
Due to their self-renewal capacity, multilineage differentiation potential, paracrine effects, and immunosuppressive properties, mesenchymal stromal cells (MSCs) are an attractive and promising tool for regenerative medicine. MSCs can be isolated from various tissues but despite their common immunophenotypic characteristics and functional properties, source-dependent differences in MSCs properties have recently emerged and lead to different clinical applications. Considered for a long time as a medical waste, umbilical cord appears these days as a promising source of MSCs. Several reports have shown that umbilical cord-derived MSCs are more primitive, proliferative, and immunosuppressive than their adult counterparts. In this review, we aim at synthesizing the differences between umbilical cord MSCs and MSCs from other sources (bone marrow, adipose tissue, periodontal ligament, dental pulp, ) with regard to their proliferation capacity, proteic and transcriptomic profiles, and their secretome involved in their regenerative, homing, and immunomodulatory capacities. Although umbilical cord MSCs are until now not particularly used as an MSC source in clinical practice, accumulating evidence shows that they may have a therapeutic advantage to treat several diseases, especially autoimmune and neurodegenerative diseases.
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Terapia Baseada em Transplante de Células e Tecidos/normas , Transplante de Células-Tronco Mesenquimais/normas , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Animais , Antineoplásicos/metabolismo , Humanos , Geleia de Wharton/citologiaRESUMO
In arterial replacement there is a clear clinical need for a functional substitute possessing appropriate haemocompatible properties to be implanted as small diameter artery. Endothelial cell seeding constitutes an appreciated method to improve blood compatibility on the condition that cells firmly adhere to the support. Along this way, an innovative technique based on multilayered polyelectrolyte films (PEM) as cell adhesive substrate was previously validated in vitro and in vivo in a small-animal model. In this study, we extended the work on a larger animal (sheep) to validate furthermore the paradigm of PEM functionalization for vascular substitutes. We tested in vitro: the efficiency of PEM to induce endothelial progenitor differentiation in sheep endothelial cells; the ability of PEM to sustain cell proliferation and allow resistance to shear stress; the fate of PEM-coated de-endothelialized human saphenous veins under flow conditions, a prerequisite step before in vivo experiments. Despite in vitro differences we were encouraged by testing in vivo PEM-coated prosthesis as carotid replacement in sheep, but without success. In order to explain the implantation failure, an in vitro haemocompatibility evaluation was performed that highlighted interspecies differences able to explain, at least in part, the graft failure obtained.
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Engenharia Tecidual/métodos , Animais , Prótese Vascular , Proliferação de Células , Células Cultivadas , Humanos , Microscopia de Contraste de Fase , Polímeros/química , Resistência ao Cisalhamento , Ovinos , Alicerces Teciduais/químicaRESUMO
The major challenge of vascular tissue engineering is to develop a small calibre vascular graft with a high patency rate. In native vessels, the thrombosis is prevented by the endothelium located at the luminal site of the vessel. The aim of this study was to develop a resistant endothelial lining on the inner surface of vascular graft using a polyelectrolyte multilayers (PEM) film. Umbilical arteries were de-endothelialized, coated with 3.5 bilayers of poly(styrene sulfonate) (PSS)/poly(allylamine hydrochloride) (PAH) and then cellularized with endothelial cells. The grafts were cultured for a week in static condition and preconditioned by exposure to a shear stress of at 1 Pa for three hours before implantation on the rabbit carotid site. Histological and confocal microscopy in vitro investigations showed that PEMs films improve cell adhesion and retention on the luminal surface after shear stress preconditioning. In vivo Doppler data showed that graft preconditioning is a crucial factor for graft patency. Indeed, preconditioned grafts remained over the whole experimental period, whereas unpreconditioned grafts were obstructed after only one week of implantation. These results open the route toward the development of a new generation of vascular substitutes having a long term patency.
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Prótese Vascular , Endotélio Vascular/citologia , Poliestirenos/química , Artérias Umbilicais/citologia , Grau de Desobstrução Vascular , Animais , Materiais Biocompatíveis/química , Adesão Celular , Células Cultivadas , Humanos , Masculino , Poliaminas/química , Coelhos , Estresse MecânicoRESUMO
Vascular tissue engineering aims to develop implantable blood-vessels, exhibiting biological and biomechanical characteristics close to those of the native vessels. The ultimate goal of our group is to engineer suitable blood vessel substitutes which could be stored for a long time in vascular bank conditions.First attempts tried to develop coating procedures allowing endothelial cells (EC) differentiation, adhesion and retention on current vascular substitutes but the weak in vivo patency of these grafts was related. Since 2003, our group have been evaluated a new surface modification of internal surface of blood vessels based on polyelectrolyte films coating. The layer-by-layer self-assembly and the resulting polyelectrolyte multiplayer films (PEM) is a simple and versatile way to engineer surfaces with highly specific properties. Previous studies indicated that the poly(sodium-4 styrene sulfonate)/poly (allylamine hydrochloride) PSS/PAH multilayered films when ended by PAH, induce strong adhesion and retention of mature EC which spread and keep their phenotype as well on glass, on expanded polytetrafluoroethylene ePTFE and on cryopreserved arteries. The mechanical properties (compliance), leading to early intimal hyperplasia and graft failure, were lost after artery cryopreservation. We have demonstrated that the compliance and elasticity restoration of PEM treated cryopreserved arteries close to native arteries.In other respect, the use of the circulating progenitor which could be differentiated into matures vascular cell offers new opportunities in vascular engineering. Currents protocols, expend at least 1 month to observe both smooth muscle (SMCs) and endothelium (ECs)-like morphology and about two months for confluent monolayer cells. The progenitor cells cultivated on PEM treated glass showed mature and functional vascular cells (SMCs and ECs) development after only 14 days of culture. The morphological appearance, mature and healthy phenotype markers expression and repartition of differentiated cells are close to mature cells.Challenge now is to build up in less a month, an autologous cellularized vascular graft using patient peripheral stem cells.