Les auteurs tiennent à remercier découverte du CRSNG 402462 &quot;échafaudages ingénierie tissulaire pour contrôler les comportements induits par les cellules souches pluripotentes&quot;.

Remarques avant de commencer le protocole: Le fibrinogène est une protéine du sang dérivé et formation à la sécurité ainsi approprié doit être rempli avant de le manipuler. Ce protocole nécessite 2 jours pour compléter ainsi le temps des cultures souches voulues de façon appropriée afin de s&#39;assurer qu&#39;ils sont prêts pour l&#39;ensemencement. En termes de calculer combien de fibrinogène de peser, trois boîtes de Pétri de 35 mm de solution saline tamponnée au tris (TBS, pH 7,4) contenant 110 à 130 mg de fibrinogène dissous dans 3 ml de TBS sera suffisante pour produire 1 24 plaques à puits contenant 400 échafaudages de fibrine ul dans chaque puits. 1. Day One: Faire des solutions de fibrinogène et de dialyse nuit <ol><li> Prenez fibrinogène lyophilisé en dehors du réfrigérateur et laisser reposer pendant 20 minutes pour lui permettre de revenir à température ambiante. </li><li> Ajouter 3 ml de solution saline tamponnée Tris (TBS) à chaque plat de 35 mm de Pétri. Chaque plaque de rendements fibrinogène 2 à 3 mL de solution de fibrinogène allant de la concentration de 12 à 20mg / ml et la quantité totale de fibrinogène nécessaire peut être calculée sur la base de ces approximations. </li><li> Peser environ 100-130 mg de fibrinogène (Fg) et saupoudrer sur la surface de la présente SCT dans chaque plat. Attendez 5 minutes pour le fibrinogène pour commencer à passer en solution. Couvrir le plat de Pétri avec couvercle. </li><li> Incuber les boîtes de Pétri à 37 ° C pendant 2 heures afin de permettre le fibrinogène pleinement entrer dans la solution de TBS. </li><li> Tube de dialyse Wet (7000 MW coupés) avec le SCT. Extrémité inférieure de la Fold l&#39;extrémité du tuyau et le collier fermé avec une pince de dialyse. </li><li> Introduire à la pipette les solutions de fibrinogène de la vaisselle dans un tube de dialyse. Pliez sur l&#39;extrémité supérieure et pince fermée avec une pince de dialyse. </li><li> Tube de dialyse Lieu contenant une solution de fibrinogène dans un récipient de 4 litres du SCT. Mélanger la solution en utilisant plaque d&#39;agitation réglé à basse vitesse (100 rpm). </li><li> Dialyser solution du jour au lendemain sur le plateau pour mélanger au moins 12 heures. La solution de TBS n&#39;a pas besoin d&#39;être changé au cours de cette période. </li></ol&gt; 2. Jour 2: La polymérisation de la fibrine et l&#39;ensemencement des échafaudages de cellules souches en échafaudages Toutes les étapes décrites dans ce processus doit être effectuée sous une hotte à la culture de tissus stérile comme ces échafaudages seront ensemencés avec des cultures de cellules souches. <ol><li> Retirer la solution de fibrinogène à partir de tubes de dialyse et le lieu dans un tube conique appropriée entreprises (soit 15 ml ou 50 ml). </li><li> Solution de fibrinogène filtre avec un filtre 5,0 um seringue pour enlever les grosses impuretés dans la solution. En fonction du volume de la solution, l&#39;utilisation de plusieurs filtres peut être nécessaire pour traiter l&#39;ensemble de la solution. </li><li> Filtre stériles de la solution de fibrinogène avec un filtre de 0,22 um dans un tube de 50 ml conique. Utilisation d&#39;une pipette taille appropriée, déterminer le volume de la solution de fibrinogène filtrée à utiliser plus tard lorsque effectuer des calculs. Selon le volume de la solution, l&#39;utilisation de plusieurs filtres peuvent être nécessaires pour traiter l&#39;entsolution la colère. </li><li> Mesurer l&#39;absorbance de la solution de fibrinogène à 280 nm en utilisant le spectrophotomètre. Un facteur de dilution de 50 est souvent nécessaire pour obtenir une absorbance de moins de 1. </li><li> Calculer la concentration de protéine présente dans la solution de fibrinogène en utilisant l&#39;équation suivante: [fibrinogène en mg / ml] = (A × 280 facteur de dilution) ÷ 1,55 1,55 où est le coefficient d&#39;extinction à 280 A pour fibrinogène humain 13. Suivant calculer la quantité de SCT nécessaire pour diluer la concentration de la solution à 11,1 mg / ml de fibrinogène sur la base de son volume initial. La concentration finale de protéines dans l&#39;échafaudage de fibrine sera de 10 mg / ml après la polymérisation. </li><li> Obtenir thrombine stérile et des solutions de chlorure de calcium. Tout d&#39;abord, ajouter 15 ul solution de thrombine (concentration: 40 U / ml - concentration finale dans échafaudage sera de 2 U / ml) à droite de chaque bien dans la première rangée de la plaque de 24 puits. Ensuite, ajouter 15 ul de 50 mM de calcium chlsolution là pour jouer à gauche de chaque puits. Enfin, ajouter 270 ul de la solution de fibrinogène à la plaque. Serrer la plaque d&#39;un côté à côté suivi par agitation arrière vers l&#39;avant pour assurer un mélange de solutions. </li><li> Laissez la ligne contenant les mélanges polymériser pendant 5 minutes à température ambiante. Les échafaudages deviennent plus opaques comme ils se polymériser. </li><li> Répétez les étapes 2.6 et 2.7 jusqu&#39;à ce que le nombre souhaité de fibrine échafaudages ont été polymérisés. </li><li> Après les 5 dernières minutes d&#39;incubation, placer les plaques à l&#39;intérieur d&#39;un incubateur à 37 ° C pour permettre la polymérisation complète d&#39;échafaudages. </li><li> Après l&#39;incubation d&#39;une heure est terminée, la prochaine étape est d&#39;ensemencer l&#39;échafaud avec des corps embryoïdes. L&#39;utilisation d&#39;un 20 pipettemen ul, sélectionnez un corps embryoïdes individu et sa place dans le centre de l&#39;échafaud de fibrine. Vérifiez avec le microscope que chaque puits contient un corps embryoïdes unique. </li><li> Ajouter 5 pi de solution de thrombine (concentration: 40 U / ml) et 5 pi de 50 mM de chlorure de calciumsolution sur le dessus de chaque corps embryoïdes suivie 90 pl de solution de fibrinogène à chaque puits. La solution doit former une bulle encapsuler les corps embryoïdes. </li><li> Placez la plaque arrière dans 37 incubateur ° C pendant une heure supplémentaire pour assurer la polymérisation. </li><li> Après incubation, ajouter 1 ml des médias appropriés de culture cellulaire à chaque plaque bien et remettez-les dans 37 ° C incubateur. </li></ol> 3. Les résultats représentatifs La figure 1 montre un schéma de la vue de côté d&#39;un puits individuel contenant le système 3D de fibrine culture échafaudage ensemencées avec un corps embryoïdes. Figure 2A montre des images représentatives de la souris cellules souches pluripotentes induites étant cultivées sur des couches nourricières de souris embryonnaires fibroblastiques. Ces cellules sont ensuite amenés à former des corps embryoïdes, agrégats de cellules contenant progéniteurs neuronaux, en utilisant une 8 jours de traitement acide rétinoïque protocole (Figure 2B) previously décrit 14, tandis que la figure 3 montre l&#39;aspect d&#39;un iPS dérivées corps embryoïdes après 3 jours de culture à l&#39;intérieur des échafaudages de fibrine 3D. Des résultats similaires ont été obtenus précédemment en utilisant des cellules souches embryonnaires de souris 7. En outre, cette méthode a été utilisée pour la culture iPS dérivées corps embryoïdes produits en utilisant un protocole différent impliquant l&#39;acide rétinoïque et purmorphamine 15 à l&#39;intérieur des échafaudages de fibrine 3D, ce qui démontre la polyvalence de ce système de culture. <img alt="Figure 1." src="/files/ftp_upload/3641/3641fig1.jpg" /> Figure 1. Schéma montrant la vue de côté d&#39;un puits individuel contenant une 3D de fibrine échafaudage tête de série avec un corps embryoïdes. <img alt="Figure 2." src="/files/ftp_upload/3641/3641fig2.jpg" /> Figure 2. Souris pluripotentes induites sur les cellules souches de la culture (iPS) et de la différenciation. Pour différencier ces cellules dans neurphénotypes al, les cellules iPS sont cultivées en suspension pour produire des agrégats de cellules appelées corps embryoïdes (EBS). Ces EB sont ensuite traités avec de l&#39;acide rétinoïque pour induire la différenciation neuronale et ce protocole a déjà été utilisé pour induire la différenciation neurale des cellules souches embryonnaires. A) indifférencié colonie de cellules iPS de souris cultivées sur des fibroblastes de souris chargeur couche embryonnaire. B) Les corps embryoïdes dérivés de cellules iPS de souris en culture en suspension prises au jour 8 après le traitement avec de l&#39;acide rétinoïque pour induire la différenciation neurale. La barre d&#39;échelle est de 100 um. <img alt="Figure 3." src="/files/ftp_upload/3641/3641fig3.jpg" /> Exemples de résultats Figure 3. De quelques iPS de souris embryoïdes corps après 3 jours de culture à l&#39;intérieur d&#39;un échafaudage 3D fibrine. Les cellules ont commencé à migrer et se différencier à l&#39;intérieur de l&#39;échafaudage de fibrine. La barre d&#39;échelle est de 500 um.

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Les auteurs n&#39;ont rien à révéler.

Ce protocole détaillé ci-dessus fournit une méthode pour générer des matrices 3D de fibrine pour la culture de cellules souches pluripotentes, spécialement pour les embryonnaire de la souris et cellules souches pluripotentes induites. Ce système 3D biomatériau culture fondée sur plus de précision imite la niche de cellules souches in vivo et ont trouvé, par conséquent, il peut être utilisé pour cribler des indices biologiques afin de déterminer leurs effets sur la différenciation des cellules so...

Équipement nécessaire: Balance analytique pH-mètre Incubateur de culture tissulaire (37 ° C, 5% de CO 2) Incorporer la plaque Spectrophotomètre Stérile hotte culture de tissus Une solution saline tamponnée Tris (pH 7,4) (Need 4 L plus assez pour dissoudre le fibrinogène) Solution à 50 mM de chlorure de calcium Stériles tubes coniques (15 ou 50 ml) 35 mm boîtes de Pétri Un tube de dialyse (7000 coupure MW) Clips de dialyse 5.0 Les filtres seringues pm Stériles enveloppés séparément des filtres de 0,22 um seringue Seringue 24 plaques à puits de culture de tissus <table border="1"><tbody><tr><td> Nom du réactif </td><td> Entreprise </td><td> Numéro de catalogue </td><td> Commentaires </td></tr><tr><td> Fibrinogène (humaine) </td><td> Calbiocourlet </td><td> 341578 </td><td></td></tr><tr><td> Thrombine (humaine) </td><td> Sigma </td><td> T7009 </td><td></td></tr></tbody></table>

preparation of 3d fibrin scaffolds for stem cell culture applications

Les cellules souches se trouvent dans naturellement microenvironnements 3D in vivo, qui sont souvent appelés la niche de cellules souches 1. Culture de cellules souches à l&#39;intérieur de la 3D échafaudages biomatériau offre un moyen de précision imiter ces microenvironnements, fournissant un avantage sur les méthodes traditionnelles de culture 2D à l&#39;aide de polystyrène ainsi que d&#39;une méthode pour les tissus de remplacement d&#39;ingénierie 2. Alors que la culture de tissus 2D polystyrène a été utilisé pour la majorité des expériences de culture cellulaire, des matrices 3D biomatériaux peuvent plus étroitement reproduire les micro-environnements trouvés in vivo, en permettant l&#39;établissement plus précis de la polarité cellulaire dans l&#39;environnement et possédant des propriétés biochimiques et mécaniques similaires aux tissus mous. 3 Une variété de dérivés naturels et synthétiques échafaudages de biomatériaux ont été étudiés comme des environnements 3D pour soutenir la croissance sur les cellules souches. Alors que les échafaudages synthétiques peuvent être synthétisés à avoir une plus grande range de propriétés mécaniques et chimiques et ont souvent une plus grande reproductibilité, biomatériaux naturels sont souvent composés de protéines et de polysaccharides présents dans la matrice extracellulaire et par conséquent contenir des sites de liaison pour l&#39;adhésion cellulaire et facilement soutenir la culture cellulaire. Échafaudages de fibrine, produite par la polymérisation du fibrinogène protéine obtenue à partir de plasma, ont été largement étudiés pour une grande variété d&#39;applications d&#39;ingénierie tissulaire à la fois in vitro et in vivo 4. Ces échafaudages peuvent être modifiés en utilisant une variété de méthodes permettant d&#39;intégrer les systèmes de libération contrôlée de la prestation des facteurs thérapeutiques 5. Des travaux antérieurs ont montré que ces échafaudages peuvent être utilisés avec succès des cellules souches embryonnaires et la culture ce système de culture basé sur échafaudage peut être utilisé pour cribler les effets de divers facteurs de croissance sur la différenciation des cellules souches ensemencées à l&#39;intérieur de 6,7. Ce protocole décrit le processus de polymerizing de fibrine à partir de solutions de fibrinogène échafaudages aide de l&#39;activité enzymatique de la thrombine. Le processus prend 2 jours pour compléter, y compris une étape de dialyse de nuit pour la solution de fibrinogène pour enlever les citrates qui inhibent la polymérisation. Ces méthodes détaillées s&#39;appuient sur les concentrations de fibrinogène jugées optimales pour la culture de cellules embryonnaires pluripotentes induites et la tige. D&#39;autres groupes ont en outre étudié les échafaudages de fibrine pour un large éventail de types de cellules et des applications - démontrant la polyvalence de cette approche 8-12.

Watch this Scientific Journal Video about Preparation of 3D Fibrin Scaffolds for Stem Cell Culture Applications at JoVE.com

Preparation of 3D Fibrin Scaffolds for Stem Cell Culture Applications

Cet ouvrage détaille la préparation de la 3D de fibrine échafaudages pour la culture et la différenciation des cellules souches plutipotent. Ces échafaudages peuvent être utilisés pour cribler les effets de divers composés biologiques sur le comportement des cellules souches ainsi que modifié pour contenir des systèmes de délivrance de médicaments.

Préparation de la 3D pour les applications de fibrine Échafaudages CULTURE DE CELLULES SOUCHES

Stem cells are found in naturally occurring 3D microenvironments in vivo, which are often referred to as the stem cell niche 1. Culturing stem cells ...

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25.1K vues.  University of Victoria. Cet ouvrage détaille la préparation de la 3D de fibrine échafaudages pour la culture et la différenciation des cellules souches plutipotent. Ces échafaudages peuvent être utilisés pour cribler les effets de divers composés biologiques sur le comportement des cellules souches ainsi que modifié pour contenir des systèmes de délivrance de médicaments.

Vidéo: Preparation of 3D Fibrin Scaffolds for Stem Cell Culture Applications

Self-reporting Scaffolds for 3-Dimensional Cell Culture

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting 3D cellular construct can often be more relevant to studying the molecular events and cell-cell interactions than similar experiments studied in 2D. To create effective 3D cultures with high cell viability throughout the scaffold the culture conditions such as oxygen and pH need to be carefully controlled as gradients in analyte concentration can exist throughout the 3D construct. Here we describe the methods of preparing biocompatible pH responsive sol-gel nanosensors and their incorporation into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds along with their subsequent preparation for the culture of mammalian cells. The pH responsive scaffolds can be used as tools to determine microenvironmental pH within a 3D cellular construct. Furthermore, we detail the delivery of pH responsive nanosensors to the intracellular environment of mammalian cells whose growth was supported by electrospun PLGA scaffolds. The cytoplasmic location of the pH responsive nanosensors can be utilized to monitor intracellular pH (pHi) during ongoing experimentation.

Biocompatible pH responsive sol-gel nanosensors can be incorporated into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds. The produced self-reporting scaffolds can be used for in&#160;situ monitoring of microenvironmental conditions whilst culturing cells upon the scaffold. This is beneficial as the 3D cellular construct can be monitored in real-time without disturbing the experiment.

Les échafaudages auto-déclaration pour les 3-Dimensional Culture cellulaire

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting ...

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Sample Preparation Strategies for Mass Spectrometry Imaging of 3D Cell Culture Models

Three dimensional cell cultures are attractive models for biological research. They combine the flexibility and cost-effectiveness of cell culture with some of the spatial and molecular complexity of tissue. For example, many cell lines form 3D structures given appropriate in vitro conditions. Colon cancer cell lines form 3D cell culture spheroids, in vitro mimics of avascular tumor nodules. While immunohistochemistry and other classical imaging methods are popular for monitoring the distribution of specific analytes, mass spectrometric imaging examines the distribution of classes of molecules in an unbiased fashion. While MALDI mass spectrometric imaging was originally developed to interrogate samples obtained from humans or animal models, this report describes the analysis of in vitro three dimensional cell cultures, including improvements in sample preparation strategies. Herein is described methods for growth, harvesting, sectioning, washing, and analysis of 3D cell cultures via matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) imaging. Using colon carcinoma 3D cell cultures as a model system, this protocol demonstrates the ability to monitor analytes in an unbiased fashion across the 3D cell culture system with MALDI-MSI.

Immortalized cancer cell lines can be grown as 3D cell cultures, a valuable model for biological research. This protocol describes mass spectrometry imaging of 3D cell cultures, including improvements in the sample preparation platform. The goal of this protocol is to instruct users to prepare 3D cell cultures for mass spectrometry imaging analysis.

Exemple Stratégies Préparation de Spectrométrie de Masse Imagerie de culture cellulaire 3D Modèles

Three dimensional cell cultures are attractive models for biological research. They combine the flexibility and cost-effectiveness of cell culture with ...

3D Hydrogel Scaffolds for Articular Chondrocyte Culture and Cartilage Generation

Human articular cartilage is highly susceptible to damage and has limited self-repair and regeneration potential. Cell-based strategies to engineer cartilage tissue offer a promising solution to repair articular cartilage. To select the optimal cell source for tissue repair, it is important to develop an appropriate culture platform to systematically examine the biological and biomechanical differences in the tissue-engineered cartilage by different cell sources. Here we applied a three-dimensional (3D) biomimetic hydrogel culture platform to systematically examine cartilage regeneration potential of juvenile, adult, and osteoarthritic (OA) chondrocytes. The 3D biomimetic hydrogel consisted of synthetic component poly(ethylene glycol) and bioactive component chondroitin sulfate, which provides a physiologically relevant microenvironment for in vitro culture of chondrocytes. In addition, the scaffold may be potentially used for cell delivery for cartilage repair in vivo. Cartilage tissue engineered in the scaffold can be evaluated using quantitative gene expression, immunofluorescence staining, biochemical assays, and mechanical testing. Utilizing these outcomes, we were able to characterize the differential regenerative potential of chondrocytes of varying age, both at the gene expression level and in the biochemical and biomechanical properties of the engineered cartilage tissue. The 3D culture model could be applied to investigate the molecular and functional differences among chondrocytes and progenitor cells from different stages of normal or aberrant development.

Cartilage repair represents an unmet medical challenge and cell-based approaches to engineer human articular cartilage are a promising solution. Here, we describe three-dimensional (3D) biomimetic hydrogels as an ideal tool for the expansion and maturation of human articular chondrocytes.

3D hydrogel échafaudages pour articulaire chondrocytes Culture and Cartilage Generation

Human articular cartilage is highly susceptible to damage and has limited self-repair and regeneration potential. Cell-based strategies to engineer ...

Fabrication of Mechanically Tunable and Bioactive Metal Scaffolds for Biomedical Applications

Biometal systems have been widely used for biomedical applications, in particular, as load-bearing materials. However, major challenges are high stiffness and low bioactivity of metals. In this study, we have developed a new method towards fabricating a new type of bioactive and mechanically reliable porous metal scaffolds-densified porous Ti scaffolds. The method consists of two fabrication processes, 1) the fabrication of porous Ti scaffolds by dynamic freeze casting, and 2) coating and densification of the porous scaffolds. The dynamic freeze casting method to fabricate porous Ti scaffolds allowed the densification of porous scaffolds by minimizing the chemical contamination and structural defects. The densification process is distinctive for three reasons. First, the densification process is simple, because it requires a control of only one parameter (degree of densification). Second, it is effective, as it achieves mechanical enhancement and sustainable release of biomolecules from porous scaffolds. Third, it has broad applications, as it is also applicable to the fabrication of functionally graded porous scaffolds by spatially varied strain during densification.

Bioactive and mechanically reliable metal scaffolds have been fabricated through a method which consists of two processes, dynamic freeze casting for the fabrication of porous Ti, and coating and densification of the Ti scaffolds. The densification process is simple, effective and applicable to the fabrication of functionally graded scaffolds.

Fabrication de mécanique accordable et bioactifs Métal échafaudages pour des applications biomédicales

Biometal systems have been widely used for biomedical applications, in particular, as load-bearing materials. However, major challenges are high stiffness ...

Micropatterning and Assembly of 3D Microvessels

In vitro platforms to study endothelial cells and vascular biology are largely limited to 2D endothelial cell culture, flow chambers with polymer or glass based substrates, and hydrogel-based tube formation assays. These assays, while informative, do not recapitulate lumen geometry, proper extracellular matrix, and multi-cellular proximity, which play key roles in modulating vascular function. This manuscript describes an injection molding method to generate engineered vessels with diameters on the order of 100 &#181;m. Microvessels are fabricated by seeding endothelial cells in a microfluidic channel embedded within a native type I collagen hydrogel. By incorporating parenchymal cells within the collagen matrix prior to channel formation, specific tissue microenvironments can be modeled and studied. Additional modulations of hydrodynamic properties and media composition allow for control of complex vascular function within the desired microenvironment. This platform allows for the study of perivascular cell recruitment, blood-endothelium interactions, flow response, and tissue-microvascular interactions. Engineered microvessels offer the ability to isolate the influence from individual components of a vascular niche and precisely control its chemical, mechanical, and biological properties to study vascular biology in both health and disease.

This manuscript presents an injection molding method to engineer microvessels that recapitulate physiological properties of endothelium. The microfluidic-based process creates patent 3D vascular networks with tailorable conditions, such as flow, cellular composition, geometry, and biochemical gradients. The fabrication process and examples of potential applications are described.

Micromodelage et l&#39;Assemblée des microvaisseaux 3D

In vitro platforms to study endothelial cells and vascular biology are largely limited to 2D endothelial cell culture, flow chambers with polymer or glass ...

Light-mediated Formation and Patterning of Hydrogels for Cell Culture Applications

Click chemistries have been investigated for use in numerous biomaterials applications, including drug delivery, tissue engineering, and cell culture. In particular, light-mediated click reactions, such as photoinitiated thiol&#8722;ene and thiol&#8722;yne reactions, afford spatiotemporal control over material properties and allow the design of systems with a high degree of user-directed property control. Fabrication and modification of hydrogel-based biomaterials using the precision afforded by light and the versatility offered by these thiol&#8722;X photoclick chemistries are of growing interest, particularly for the culture of cells within well-defined, biomimetic microenvironments. Here, we describe methods for the photoencapsulation of cells and subsequent photopatterning of biochemical cues within hydrogel matrices using versatile and modular building blocks polymerized by a thiol&#8722;ene photoclick reaction. Specifically, an approach is presented for constructing hydrogels from allyloxycarbonyl (Alloc)-functionalized peptide crosslinks and pendant peptide moieties and thiol-functionalized poly(ethylene glycol) (PEG) that rapidly polymerize in the presence of lithium acylphosphinate photoinitiator and cytocompatible doses of long wavelength ultraviolet (UV) light. Facile techniques to visualize photopatterning and quantify the concentration of peptides added are described. Additionally, methods are established for encapsulating cells, specifically human mesenchymal stem cells, and determining their viability and activity. While the formation and initial patterning of thiol-alloc hydrogels are shown here, these techniques broadly may be applied to a number of other light and radical-initiated material systems (e.g., thiol-norbornene, thiol-acrylate) to generate patterned substrates.

We describe a sequential process for light-mediated formation and subsequent biochemical patterning of synthetic hydrogel matrices for three-dimensional cell culture applications. The construction and modification of hydrogels with cytocompatible photoclick chemistry is demonstrated. Additionally, facile techniques to quantify and observe patterns and determine cell viability within these hydrogels are presented.

Formation et Patterning Light-médiée hydrogels pour la culture cellulaire Applications

Click chemistries have been investigated for use in numerous biomaterials applications, including drug delivery, tissue engineering, and cell culture. In ...

Synthesis of Biocompatible Liquid Crystal Elastomer Foams as Cell Scaffolds for 3D Spatial Cell Cultures

Here, we present a step-by-step preparation of a 3D, biodegradable, foam-like cell scaffold. These scaffolds were prepared by cross-linking star block co-polymers featuring cholesterol units as side-chain pendant groups, resulting in smectic-A (SmA) liquid crystal elastomers (LCEs). Foam-like scaffolds, prepared using metal templates, feature interconnected microchannels, making them suitable as 3D cell culture scaffolds. The combined properties of the regular structure of the metal foam and of the elastomer result in a 3D cell scaffold that promotes not only higher cell proliferation compared to conventional porous templated films, but also better management of mass transport (i.e., nutrients, gases, waste, etc.). The nature of the metal template allows for the easy manipulation of foam shapes (i.e., rolls or films) and for the preparation of scaffolds of different pore sizes for different cell studies while preserving the interconnected porous nature of the template. The etching process does not affect the chemistry of the elastomers, preserving their biocompatible and biodegradable nature. We show that these smectic LCEs, when grown for extensive time periods, enable the study of clinically relevant and complex tissue constructs while promoting the growth and proliferation of cells.

This study presents a methodology to prepare 3D, biodegradable, foam-like cell scaffolds based on biocompatible side-chain liquid crystal elastomers (LCEs). Confocal microscopy experiments show that foam-like LCEs allow for cell attachment, proliferation, and the spontaneous alignment of C2C12s myoblasts.

Synthèse de cristaux liquides biocompatibles mousses élastomères comme échafaudages cellulaires pour les cultures de cellules spatiales 3D

Here, we present a step-by-step preparation of a 3D, biodegradable, foam-like cell scaffold. These scaffolds were prepared by cross-linking star block ...

Construction of a Multilayered Mesenchymal Stem Cell Sheet with a 3D Dynamic Culture System

Stem cell therapy shows a promising future in regenerating injured organ and tissues, and the cell sheet technique has been developed to improve the low cell retention and poor survival within the target zone. However, during the in vitro construction process, a solution for maintaining stem cell bioactivity and increasing the cell amount within the cell sheet is urgently needed. Here, this protocol presents a method for constructing a multilayered cell sheet with favorable stem cell bioactivity and optimal operability. Decellularized porcine pericardium (DPP) is prepared by phospholipase A2 (PLA2) decellularization method as the cell sheet scaffold, and rat bone marrow mesenchymal stem cells (BMSCs) are isolated and expanded as the seeded cells. The temporary multilayered cell sheet structure is constructed by using RAD16-I peptide hydrogel. Finally, the cell sheet is cultured with a dynamic perfusion system to stabilize the three-dimensional (3D) structure, and the cell sheet could be obtained following a 48-hour culture in vitro. This protocol provides an efficient and feasible method for constructing a multilayered stem cell sheet, and the cell sheet could be developed as a favorable stem cell therapy product in the future.

This article provides an efficient and feasible method for constructing multilayered stem cell sheets with favorable stem cell property.

Construction d’une feuille les cellules souches mésenchymateuses multicouche avec un système de Culture dynamique 3D

Stem cell therapy shows a promising future in regenerating injured organ and tissues, and the cell sheet technique has been developed to improve the low ...

A Culture Method to Maintain Quiescent Human Hematopoietic Stem Cells

Human hematopoietic stem cells (HSCs), like other mammalian HSCs, maintain lifelong hematopoiesis in the bone marrow. HSCs remain quiescent in vivo, unlike more differentiated progenitors, and enter the cell cycle rapidly after chemotherapy or irradiation to treat bone marrow injury or in vitro culture. By mimicking the bone marrow microenvironment in the presence of abundant fatty acids, cholesterol, low concentration of cytokines, and hypoxia, human HSCs maintain quiescence in vitro. Here, a detailed protocol for maintaining functional HSCs in the quiescent state in vitro is described. This method will enable studies of the behavior of human HSCs under physiological conditions.

This protocol enables the maintenance of quiescent human hematopoietic stem cells in vitro by mimicking the bone marrow microenvironment using abundant fatty acids, cholesterol, lower concentrations of cytokines, and hypoxia.

Une méthode de culture pour maintenir les cellules souches hématopoïétiques humaines quiescentes

Human hematopoietic stem cells (HSCs), like other mammalian HSCs, maintain lifelong hematopoiesis in the bone marrow. HSCs remain quiescent in vivo, ...

Preparation and Characterization of Graphene-Based 3D Biohybrid Hydrogel Bioink for Peripheral Neuroengineering

Peripheral neuropathies can occur as a result of axonal damage, and occasionally due to demyelinating diseases. Peripheral nerve damage is a global problem that occurs in 1.5%-5% of emergency patients and may lead to significant job losses. Today, tissue engineering-based approaches, consisting of scaffolds, appropriate cell lines, and biosignals, have become more applicable with the development of three-dimensional (3D) bioprinting technologies. The combination of various hydrogel biomaterials with stem cells, exosomes, or bio-signaling molecules is frequently studied to overcome the existing problems in peripheral nerve regeneration. Accordingly, the production of injectable systems, such as hydrogels, or implantable conduit structures formed by various bioprinting methods has gained importance in peripheral neuro-engineering. Under normal conditions, stem cells are the regenerative cells of the body, and their number and functions do not decrease with time to protect their populations; these are not specialized cells but can differentiate upon appropriate stimulation in response to injury. The stem cell system is under the influence of its microenvironment, called the stem cell niche. In peripheral nerve injuries, especially in neurotmesis, this microenvironment cannot be fully rescued even after surgically binding severed nerve endings together. The composite biomaterials and combined cellular therapies approach increases the functionality and applicability of materials in terms of various properties such as biodegradability, biocompatibility, and processability. Accordingly, this study aims to demonstrate the preparation and use of graphene-based biohybrid hydrogel patterning and to examine the differentiation efficiency of stem cells into nerve cells, which can be an effective solution in nerve regeneration.

In this manuscript, we demonstrate the preparation of a biohybrid hydrogel bioink containing graphene for use in peripheral tissue engineering. Using this 3D biohybrid material, the neural differentiation protocol of stem cells is performed. This can be an important step in bringing similar biomaterials to the clinic.

Préparation et caractérisation de bio-encre d’hydrogel biohybride 3D à base de graphène pour la neuro-ingénierie périphérique

Peripheral neuropathies can occur as a result of axonal damage, and occasionally due to demyelinating diseases. Peripheral nerve damage is a global ...