Os autores gostariam de agradecer NSERC Discovery Grant 402462 &quot;andaimes da engenharia de tecidos para controlar pluripotentes induzidas comportamento de células-tronco&quot;.

Notas antes de iniciar o protocolo: O fibrinogênio é uma proteína derivada de sangue e treinamento de segurança, pois, adequado deve ser concluída antes do manuseio. Este protocolo requer 2 dias para ser concluído assim que o tempo das culturas-tronco desejadas de forma adequada para garantir que eles estão prontos para a semeadura. Em termos de cálculo quanto fibrinogénio a pesar, três pratos 35 mm de petri de solução salina tamponada com tris (TBS, pH 7,4) contendo 110-130 mg de fibrinogénio dissolvido em 3 mL de TBS será suficiente para produzir uma placa de 24 poços contendo 400 uL andaimes de fibrina em cada poço. 1. Dia: Fazendo soluções de fibrinogênio e diálise durante a noite <ol><li> Tome fibrinogênio liofilizado da geladeira e deixe descansar por 20 minutos para permitir que a temperatura ambiente. </li><li> Adicionar 3 ml de solução salina tamponada com Tris (TBS) a cada placa de Petri de 35 mm. Cada placa de rendimentos de fibrinogénio 2-3 mL de solução de fibrinogénio variando em concentração de 12-20mg / mL e da quantidade total de fibrinogénio necessária pode ser calculada com base na estas aproximações. </li><li> Pesar cerca de 100-130 mg de fibrinogénio (Fg) e salpique para a superfície do presente TBS em cada prato. Espere 5 minutos para que o fibrinogénio para começar a entrar em solução. Cubra placa de Petri com tampa. </li><li> Pratos de Petri incubar a 37 ° C durante 2 horas para permitir que o fibrinogénio em totalmente ir para dentro da solução de TBS. </li><li> Tubo de diálise Wet (7000 MW cortado) com TBS. Extremidade inferior dobra da extremidade da tubagem e se fecham com uma braçadeira de diálise. </li><li> Pipetar as soluções de fibrinogénio a partir de pratos em tubo de diálise. Dobre extremidade superior e se fecham com uma braçadeira de diálise. </li><li> Tubo de diálise contendo o local de solução de fibrinogénio em um recipiente de 4 litros de TBS. Solução mistura usando placa de agitação definido para a baixa velocidade (100 rpm). </li><li> Dialisar solução durante a noite em agitar placa durante, pelo menos, 12 horas. A solução de TBS não precisa de ser alterada ao longo deste período de tempo. </li></ol&gt; 2. Dia 2: Polimerização de andaimes de fibrina e semeadura de células estaminais em andaimes Todos os passos descritos para este processo deve ser realizado em um capuz estéril de cultura de tecidos como estes suportes serão semeada com culturas de células estaminais. <ol><li> Remover a solução de fibrinogénio a partir de tubo de diálise e coloque em um tubo de tamanho apropriado cónica (quer mL 15 ou 50 mL). </li><li> Solução de fibrinogénio filtro com um filtro de seringa de 5,0 mm a remover as impurezas grandes na solução. Dependendo do volume da solução, a utilização de filtros múltiplos pode ser necessário para processar a solução inteira. </li><li> Filtro estéril, a solução de fibrinogénio com um filtro de 0,22 um para um tubo de 50 mL cónico. Usando uma pipeta de tamanho adequado, determinar o volume da solução de fibrinogénio filtrou-se para uso posterior ao fazer cálculos. Dependendo do volume da solução, a utilização de filtros múltiplos pode ser necessário para processar a entsolução ira. </li><li> Medir a absorvância da solução de fibrinogénio a 280 nm utilizando o espectrofotómetro. Um factor de diluição de 50 vezes é necessário para obter uma absorvância inferior a 1. </li><li> Calcular a concentração de proteína presente na solução de fibrinogénio através da seguinte equação: [Fibrinogénio em mg / mL] = (A 280 × factor de diluição) ÷ 1,55 1,55 onde é o coeficiente de extinção a 280 A para o fibrinogénio humano 13. Em seguida calcular a quantidade de TBS necessário para diluir a concentração da solução a 11,1 mg / mL de fibrinogénio com base no volume inicial. A concentração final de proteína na andaimes de fibrina será de 10 mg / mL, após a polimerização. </li><li> Obter trombina estéril e soluções de cloreto de cálcio. Em primeiro lugar, adicionar 15 uL solução de trombina (concentração: 40 U / mL - concentração final no andaime será de 2 U / mL) para o lado direito de cada poço na primeira linha da placa de 24 poços. Em seguida, adicionar 15 uL de 50 mM de cálcio chlsolução oride para o lado esquerdo de cada poço. Finalmente, adicionar 270 uL da solução de fibrinogénio ao prato. Agitar placa de lado a lado, seguido por agitação trás para a frente para assegurar a mistura de soluções. </li><li> Deixe a linha que contém as misturas polimerizar durante 5 minutos à temperatura ambiente. Os andaimes tornam-se mais opaca como polimerização. </li><li> Repetir os passos 2.6 e 2.7 até que o número desejado de andaimes de fibrina foram polimerizados. </li><li> Após a incubação último minuto 5, colocar as placas dentro de uma incubadora a 37 ° C para permitir a polimerização completa de andaimes. </li><li> Após a incubação de uma hora é completa, o próximo passo é a semente da andaime com corpos embrióides. Usando um 20 pipettemen microlitro, selecione um corpo embrióides individual e lugar no centro do andaime de fibrina. Verifique com microscópio que cada poço contenha um corpo único embrióides. </li><li> Adicionar 5 uL de solução de trombina (concentração: 40 U / mL) e 5 uL de 50 mM de cloreto de cálciosolução no topo de cada corpo embrióides seguido por 90 uL de solução de fibrinogénio a cada poço. A solução deve formar uma bolha encapsulando os corpos embrióides. </li><li> Colocar a placa de volta em 37 ° C incubadora durante uma hora adicional para assegurar a polimerização. </li><li> Após a incubação, adicionar 1 mL de meio de cultura de células apropriadas para cada placa bem e de volta para o local de 37 ° C incubadora. </li></ol> 3. Os resultados representativos A Figura 1 mostra um diagrama esquemático do vista lateral de um indivíduo bem contendo o 3D fibrina sistema de cultura de andaime semeado com um corpo embrióides. Figura 2A mostra imagens representativas de rato células pluripotentes induzidas estaminais a ser cultivado em camadas alimentadoras de fibroblastos de rato embrionários. Estas células são então induzida a formar corpos embrióides, agregados de células que contenham progenitores neurais, utilizando um ácido retinóico 8 dias de tratamento protocolo (Figura 2B) como previously descrito 14 enquanto que a Figura 3 mostra o aspecto de um IPS-derivada corpo embrióides após 3 dias de cultura dentro de andaimes 3D de fibrina. Resultados semelhantes têm sido obtidos anteriormente usando células de ratinho estaminais embrionárias 7. Além disso, este método tem sido utilizado para a cultura IPS-derivados corpos embrióides produzido usando um protocolo diferente envolvendo ácido retinóico e purmorphamine 15 dentro de andaimes 3D de fibrina, demonstrando a versatilidade da presente sistema de cultura. <img alt="Figura 1." src="/files/ftp_upload/3641/3641fig1.jpg" /> Figura 1. Esquemático, mostrando a vista lateral de um indivíduo bem contendo um 3D fibrina andaime semeado com um corpo embrióides. <img alt="Figura 2." src="/files/ftp_upload/3641/3641fig2.jpg" /> Figura 2. Rato tronco pluripotentes induzidas cultura de células (iPS) e diferenciação. Para diferenciar essas células em neurfenótipos al, as células iPS são cultivadas em suspensão para produzir agregados de células chamados corpos embrióides (EBS). Estes EBS são então tratadas com ácido retinóico para induzir a diferenciação neuronal e este protocolo foi previamente utilizado para induzir a diferenciação neuronal das células estaminais embrionárias. A) Indiferenciado rato colônia de células iPS cultivadas sobre uma camada de fibroblastos embrionários alimentador do mouse. B) corpos embrióides derivados de células de rato iPS em cultura em suspensão tomada no dia 8 após tratamento com ácido retinóico para induzir a diferenciação neuronal. Barra de escala é 100 mm. <img alt="Figura 3." src="/files/ftp_upload/3641/3641fig3.jpg" /> Resultados Figura 3. Exemplo de um mouse iPS embrióides corpo após 3 dias de cultura dentro de um andaime 3D fibrina. As células começaram a migrar e se diferenciar dentro do andaime de fibrina. Barra de escala é 500 mm.

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Os autores não têm nada a revelar.

Este protocolo detalhado acima fornece um método para a geração de andaimes 3D de fibrina para a cultura de células estaminais pluripotentes, especificamente para o rato embrionário e células estaminais pluripotentes induzidas. Este sistema de cultura de 3D ​​biomaterial baseado com mais precisão imita o nicho de células-tronco encontrada in vivo e, como resultado, pode ser utilizado para rastrear sinais biológicos para determinar os seus efeitos sobre a diferenciação de células-tronco ...

Equipamento necessário: Balança analítica medidor de pH De cultura de tecidos incubadora (37 ° C, 5% de CO 2) Mexa placa Espectrofotômetro Capa cultura estéril tecido Solução salina tamponada com Tris (pH 7,4) (4 Necessita L mais suficiente para dissolver o fibrinogénio) 50 mM de solução de cloreto de cálcio Estéreis tubos cónicos (15 ou 50 mL) 35 mm placas de Petri Tubo de diálise (7.000 corte MW) Clipes de diálise 5.0 uM filtros de seringa Embalados individualmente estéril de 0,22 mM de seringas filtros Seringa 24 placas de cultura de tecidos <table border="1"><tbody><tr><td> Nome do reagente </td><td> Companhia </td><td> Número de catálogo </td><td> Comentários </td></tr><tr><td> Fibrinogénio (humano) </td><td> Calbiocbainha </td><td> 341578 </td><td></td></tr><tr><td> A trombina (humano) </td><td> Sigma </td><td> T7009 </td><td></td></tr></tbody></table>

preparation of 3d fibrin scaffolds for stem cell culture applications

As células estaminais são encontrados em que ocorre naturalmente microambientes 3D in vivo, os quais são muitas vezes referida como a célula nicho haste 1. A cultura de células-tronco dentro de 3D ​​biomaterial andaimes fornece uma maneira para exatidão imitar estes microambientes, proporcionando uma vantagem sobre os métodos tradicionais de cultura 2D usando poliestireno, bem como um método para tecidos de engenharia de substituição 2. Enquanto polystrene cultura 2D tecido tem sido utilizada para a maioria das experiências de cultura de células, andaimes 3D biomaterial pode mais estreitamente replicar os microambientes encontrados in vivo, permitindo estabelecimento mais precisa da polaridade de células no meio ambiente e possuindo propriedades bioquímicas e mecânicas semelhantes a tecido mole. 3 A variedade de origem natural e andaimes biomaterial sintético têm sido investigados como ambientes 3D para apoiar o crescimento de células-tronco. Enquanto andaimes sintéticos podem ser sintetizados a ter uma maior range de propriedades mecânicas e químicas e muitas vezes têm uma maior reprodutibilidade, biomateriais naturais são frequentemente compostas de proteínas e polissacáridos encontrados na matriz extracelular e, como resultado contêm sítios de ligação para a adesão celular e prontamente suporte de cultura de células. Fibrina andaimes, produzido por polimerização do fibrinogénio proteína obtida a partir de plasma, têm sido amplamente investigados para uma variedade de aplicações de engenharia de tecidos tanto in vitro como in vivo 4. Tais suportes pode ser modificada usando uma variedade de métodos para incorporar os sistemas de libertação controlada para a entrega de factores terapêuticos 5. O trabalho anterior mostrou que andaimes tais pode ser utilizado com sucesso para a cultura de células estaminais embrionárias e este sistema de cultura de andaime baseado pode ser usado para examinar os efeitos de vários factores de crescimento sobre a diferenciação das células-tronco semeadas dentro 6,7. Este detalhes protocolo do processo de polymerizing de fibrina scaffolds a partir de soluções de fibrinogénio, usando a actividade enzimática da trombina. O processo leva 2 dias para se completar, incluindo um passo de diálise durante a noite para a solução de fibrinogénio para remover citratos que inibem a polimerização. Estes métodos detalhados contar com as concentrações de fibrinogênio determinados a ser o ideal para embrionário e induzida por cultura de células pluripotentes estaminais. Outros grupos têm investigado andaimes de fibrina para uma vasta gama de tipos de células e aplicações - demonstrando a versatilidade desta abordagem 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

Isso detalhes o trabalho de preparação de fibrina scaffolds 3D para cultura e diferenciação das células-tronco plutipotent. Tais suportes podem ser usados ​​para examinar os efeitos de vários compostos biológicos sobre o comportamento das células estaminais, bem como modificada para conter sistemas de entrega de drogas.

Preparação de fibrina Andaimes 3D para aplicações de cultura de células-tronco

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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Bioengineering

25.1K visualizações.  University of Victoria. Isso detalhes o trabalho de preparação de fibrina scaffolds 3D para cultura e diferenciação das células-tronco plutipotent. Tais suportes podem ser usados ​​para examinar os efeitos de vários compostos biológicos sobre o comportamento das células estaminais, bem como modificada para conter sistemas de entrega de drogas.

Vídeo: 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.

Andaimes auto-relato para cultura de células 3-Dimensional

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

Bioengenharia

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.

Amostra Estratégias Preparação para Mass Spectrometry imagem da cultura celular 3D Models

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 Hidrogel Andaimes para articular de condrócitos Cultura e Geração de cartilagem

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.

Fabricação de Mecanicamente Tunable e Bioativos metal andaimes para aplicações biomédicas

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.

Micropatterning e Montagem de microvasos 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.

Formação Light-mediada e padronização de hidrogéis para aplicações de cultura celular

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.

Síntese de biocompatíveis cristal líquido de elastómero Espumas como andaimes celulares para cultura de células 3D espaciais

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.

Construção de uma folha de células-tronco mesenquimais em várias camadas com um sistema de cultura dinâmica 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.

Um método cultural para manter células-tronco hematopoiéticas humanas 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.

Preparação e caracterização de biotinta de hidrogel biohíbrido 3D à base de grafeno para neuroengenharia periférica

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