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1.
J Biomed Mater Res A ; 111(1): 71-87, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36129207

RESUMO

Tissue engineering is an alternative method for preparing small-caliber (<6 mm) vascular grafts. Dynamic mechanical conditioning is being researched as a method to improve mechanical properties of tissue engineered blood vessels. This method attempts to induce unique reaction in implanted cells that regenerate the matrix around them, thereby improving the overall mechanical stability of the grafts. In this study, we used a bioreactor to seed endothelial cells and smooth muscle cells into the inner and outer layers of the electrospun spider silk protein scaffold respectively to construct vascular grafts. The cell proliferation, mechanical properties, blood compatibility and other indicators of the vascular grafts were characterized in vitro. Furthermore, the vascular grafts were implanted in Sprague Dawley rats, and the vascular grafts' patency, extracellular matrix formation, and inflammatory response were evaluated in vivo. We aimed to construct spider silk protein vascular grafts with the potential for in vivo implantation by using a pulsating flow bioreactor. The results showed that, when compared with the static culture condition, the dynamic culture condition improved cell proliferation on vascular scaffolds and enhanced mechanical function of vascular scaffolds. In vivo experiments also showed that the dynamic culture of vascular grafts was more beneficial for the extracellular matrix deposition and anti-thrombogenesis, as well as reducing the inflammatory response of vascular grafts. In conclusion, dynamic mechanical conditioning aid in the resolution of challenges impeding the application of electrospun scaffolds and have the potential to construct small-caliber blood vessels with regenerative function for cardiovascular tissue repair.


Assuntos
Seda , Engenharia Tecidual , Ratos , Animais , Engenharia Tecidual/métodos , Tecidos Suporte , Células Endoteliais , Ratos Sprague-Dawley , Prótese Vascular
2.
J Biomed Mater Res A ; 111(1): 106-117, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36194510

RESUMO

The properties and structure of the cellular microenvironment can influence cell behavior. Sites of cell adhesion to the extracellular matrix (ECM) initiate intracellular signaling that directs cell functions such as proliferation, differentiation, and apoptosis. Electrospun fibers mimic the fibrous nature of native ECM proteins and cell culture in fibers affects cell shape and dimensionality, which can drive specific functions, such as the osteogenic differentiation of primary human bone marrow stromal cells (hBMSCs), by. In order to probe how scaffolds affect cell shape and behavior, cell-fiber contacts were imaged to assess their shape and dimensionality through a novel approach. Fluorescent polymeric fiber scaffolds were made so that they could be imaged by confocal fluorescence microscopy. Fluorescent polymer films were made as a planar control. hBSMCs were cultured on the fluorescent substrates and the cells and substrates were imaged. Two different image analysis approaches, one having geometrical assumptions and the other having statistical assumptions, were used to analyze the 3D structure of cell-scaffold contacts. The cells cultured in scaffolds contacted the fibers in multiple planes over the surface of the cell, while the cells cultured on films had contacts confined to the bottom surface of the cell. Shape metric analysis indicated that cell-fiber contacts had greater dimensionality and greater 3D character than the cell-film contacts. These results suggest that cell adhesion site-initiated signaling could emanate from multiple planes over the cell surface during culture in fibers, as opposed to emanating only from the cell's basal surface during culture on planar surfaces.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Tecidos Suporte/química , Diferenciação Celular , Matriz Extracelular/metabolismo , Células Cultivadas , Engenharia Tecidual/métodos , Células da Medula Óssea
3.
J Biomed Mater Res A ; 111(1): 118-131, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36205385

RESUMO

Lyophilization of protein solutions, such as silk fibroin (silk), produces porous scaffolds useful for tissue engineering (TE). The impact of modifying lyophilization primary drying parameters on scaffold properties has not yet been explored previously. In this work, changes to primary drying duration and temperature were investigated using 3%, 6%, 9%, and 12% (w/v) silk solutions, via protocols labeled as Long Hold, Slow Ramp, and Standard. The 9% and 12% scaffolds were not successfully fabricated using the Standard protocol, while the Long Hold and Slow Ramp protocols resulted in scaffolds from all silk solution concentrations. Scaffolds fabricated using the Long Hold protocol had higher Young's moduli, smaller pore Feret diameters, and faster degradation. To investigate the utility of the different lyophilized scaffolds for in vitro cell culturing, the HepaRG liver cell line was cultured in the 3% to 12% scaffolds fabricated using the Long Hold protocol. The HepaRG cells grown in 3% scaffolds initially had greater lipid accumulation and metabolic activity than the other groups, although these differences were no longer apparent by Day 28. The deoxyribonucleic acid content of the HepaRG cells grown in 3% scaffold group was also initially significantly higher than the other groups. Significant differences in gene expression by 9% scaffolded HepaRG cells (CK19, HNFα) were seen on Day 14 while significant differences by 12% scaffolded HepaRG cells (ALB, APOA4) were seen on Day 28. Overall, modifying the primary drying parameters and silk concentration resulted in lyophilized scaffolds with tunable properties useful for TE applications.


Assuntos
Fibroínas , Seda , Porosidade , Tecidos Suporte , Temperatura , Engenharia Tecidual , Liofilização
4.
J Biomed Mater Res B Appl Biomater ; 111(1): 51-61, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35799479

RESUMO

Spinal cord injury (SCI) will lead to irreversible damage of sensory and motor function of central nervous system, which seriously affects patient's quality of life. A variety of nerve engineering materials carrying various stem cells and cell growth factors had used to promote the repair of SCI, but they could not mimic the actual matric niche at spinal cord to promote cell proliferation and differentiation. Thus, developing novel biomaterial providing better niche of spinal cord is a new strategy to treat the severe SCI. In this study, we constructed porcine spinal cord decellularized matrix scaffold (SC-DM) with biocompatibility to load engineered basic fibroblast growth factor-overexpressing human umbilical cord mesenchymal stromal cells (bFGF-HUCMSCs) for treating SCI. The continuously released bioactive bFGF factors from grafted bFGF-HUCMSCs and three-dimensional niche by SC-DM promoted the differentiation of endogenous stem cells into neurons with nerve conduction function, leading a markedly motor function recovery of SCI. These results indicated that the functional bFGF-HUCMSCs/SC-DM scaffold provided more suitable matric niche for nerve cells, that would be a promising strategy for the clinical application of SCI.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Humanos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Qualidade de Vida , Traumatismos da Medula Espinal/metabolismo , Tecidos Suporte , Cordão Umbilical/citologia , Animais
5.
Carbohydr Polym ; 300: 120264, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372515

RESUMO

After bone tumor resection, the severe complications including cancer recurrence, infection and extensive bone loss are still a challenge. To address this problem, a chitosan/hydroxypropyltrimethyl ammonium chloride chitosan/hydroxyapatite/black phosphorus (CS/HC/HA/BP) hybrid photothermal scaffold with a multistage photothermal strategy was developed. HC-stabilized BP endowed the scaffold with simultaneous antitumor/antibacterial properties under photothermal stimulation of <50 °C. Subsequently, excellent osteogenesis could be achieved with mild hyperthermia stimulation (∼42 °C) through up-regulating the expressions of heat shock proteins. Under NIR irradiation, the scaffold could eliminate 95 % of osteosarcoma cells as well as 97 % of E. coli and 92 % of S. aureus. The osteogenic gene expressions of ALP, COL 1A1, and OCN in photothermal group were 1.64, 1.31 and 1.27 folds higher than that of non-photothermal group in vivo, respectively. Therefore, the obtained scaffold synergized with multistage photothermal strategy was effective and a reference for the treatment of other complex diseases.


Assuntos
Neoplasias Ósseas , Quitosana , Humanos , Quitosana/uso terapêutico , Tecidos Suporte , Staphylococcus aureus , Escherichia coli , Osteogênese , Neoplasias Ósseas/terapia
6.
Carbohydr Polym ; 300: 120266, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372517

RESUMO

Acute myocardial infarction (AMI), which cut down blood flow to the myocardium, is a serious health-threatening disorder that causes remarkable morbidity and mortality. To date, scaffolds have opened new prospects for potential applications for cardiac regeneration after AMI. The hybrid scaffolds as novel strategies can improve the performance of scaffolds. Chitosan is a naturally safe copolymer with good biocompatibility and biodegradability. Recently, chitosan-based formulations have attracted a lot of interest for scaffolds fabrication. Regarding, chitosan-based hybrid scaffolds have a wide application in cardiac tissue regeneration. This review is focused on the recent progression of the various biodegradable chitosan hybrid-based scaffolds (hydrogels, nanofibers, patch) that have been designed for cardiac engineering. Besides, we discussed, in short, the future perspective and challenges of these types of scaffolds.


Assuntos
Quitosana , Infarto do Miocárdio , Nanofibras , Humanos , Tecidos Suporte , Engenharia Tecidual , Nanofibras/uso terapêutico , Infarto do Miocárdio/terapia
7.
Braz. j. biol ; 83: e246592, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339408

RESUMO

Abstract Mesenchymal stem cells (MSCs) have great potential for application in cell therapy and tissue engineering procedures because of their plasticity and capacity to differentiate into different cell types. Given the widespread use of MSCs, it is necessary to better understand some properties related to osteogenic differentiation, particularly those linked to biomaterials used in tissue engineering. The aim of this study was to develop an analysis method using FT-Raman spectroscopy for the identification and quantification of biochemical components present in conditioned culture media derived from MSCs with or without induction of osteogenic differentiation. All experiments were performed between passages 3 and 5. For this analysis, MSCs were cultured on scaffolds composed of bioresorbable poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(ε-caprolactone) (PCL) polymers. MSCs (GIBCO®) were inoculated onto the pure polymers and 75:25 PHBV/PCL blend (dense and porous samples). The plate itself was used as control. The cells were maintained in DMEM (with low glucose) containing GlutaMAX® and 10% FBS at 37oC with 5% CO2 for 21 days. The conditioned culture media were collected and analyzed to probe for functional groups, as well as possible molecular variations associated with cell differentiation and metabolism. The method permitted to identify functional groups of specific molecules in the conditioned medium such as cholesterol, phosphatidylinositol, triglycerides, beta-subunit polypeptides, amide regions and hydrogen bonds of proteins, in addition to DNA expression. In the present study, FT-Raman spectroscopy exhibited limited resolution since different molecules can express similar or even the same stretching vibrations, a fact that makes analysis difficult. There were no variations in the readings between the samples studied. In conclusion, FT-Raman spectroscopy did not meet expectations under the conditions studied.


Resumo As células-tronco mesenquimais (MSCs) possuem grande potencial para aplicação em procedimentos terapêuticos ligados a terapia celular e engenharia de tecidos, considerando-se a plasticidade e capacidade de formação em diferentes tipos celulares por elas. Dada a abrangência no emprego das MSCs, há necessidade de se compreender melhor algumas propriedades relacionadas à diferenciação osteogênica, particularmente liga à biomateriais usados em engenharia de tecidos. Este projeto objetiva o desenvolvimento de uma metodologia de análise empregando-se a FT-Raman para identificação e quantificação de componentes bioquímicos presentes em meios de cultura condicionados por MSCs, com ou sem indução à diferenciação osteogênica. Todos os experimentos foram realizados entre as passagens 3 e 5. Para essas análises, as MSCs foram cultivadas sobre arcabouços de polímeros biorreabsorvíveis de poli (hidroxibutirato-co-hidroxivalerato) (PHBV) e o poli (ε-caprolactona) (PCL). As MSCs (GIBCO®) foram inoculadas nos polímeros puros e na mistura 75:25 de PHBV / PCL (amostras densas e porosas). As células foram mantidas em DMEM (com baixa glicose) contendo GlutaMAX® e 10% de SFB a 37oC com 5% de CO2 por 21 dias. A própria placa foi usada como controle. Os meios de cultura condicionados foram coletados e analisadas em FT-Raman para sondagem de grupos funcionais, bem como possíveis variações moleculares associadas com a diferenciação e metabolismo celular. Foi possível discernir grupos funcionais de moléculas específicas no meio condicionado, como colesterol, fosfatidilinositol, triglicerídeos, forma Beta de polipeptídeos, regiões de amida e ligações de hidrogênio de proteínas, além da expressão de DNA. Na presente avaliação, a FT-Raman apresentou como uma técnica de resolução limitada, uma vez que modos vibracionais de estiramento próximos ou mesmo iguais podem ser expressos por moléculas diferente, dificultando a análise. Não houve variações nas leituras entre as amostras estudadas, concluindo-se que a FT-Raman não atendeu às expectativas nas condições estudadas.


Assuntos
Animais , Ratos , Células-Tronco Mesenquimais , Osteogênese , Poliésteres , Análise Espectral Raman , Meios de Cultivo Condicionados , Proliferação de Células , Tecidos Suporte
8.
Methods Mol Biol ; 2598: 1-7, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36355280

RESUMO

Once damaged, cartilage has limited healing capability. This has led to a huge body of research that aims to repair or regenerate this important tissue. Despite the progress made, significant hurdles still need to be overcome. This chapter highlights some of the progress made, while elaborating on areas that need further research. The concept of translation and the route to clinical translation must be kept in mind if some of the promising preclinical research is to make it to routine clinical application.


Assuntos
Cartilagem Articular , Engenharia Tecidual , Medicina Regenerativa , Tecidos Suporte
9.
Methods Mol Biol ; 2598: 301-311, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36355300

RESUMO

Removing cellular material from a tissue, a process called decellularization, reduces the risk of adverse host reactions, allows for efficient decontamination, and extends the shelf-life of the matrix. It facilitates the use of cartilage tissue as human-derived allograft, thus providing the field of cartilage regeneration with a biomaterial unmatched in its similarity to native cartilage in terms of structure, composition, and mechanical properties.The dense extracellular matrix of articular cartilage requires a particularly thorough process to achieve the removal of cells, cell debris, and reagents used in the process. In our studies (Nürnberger et al., EBioMedicine 64:103196, 2021; Schneider et al., Tissue Eng Part C Methods 22(12):1095-1107, 2016), we have successfully developed a protocol for achieving decellularization via physical, chemical, and enzymatic steps. Combining freeze-thaw cycles for devitalization, hydrochloric acid as decellularization agent and the enzymatic removal of glycosaminoglycans, results in an acellular scaffold that is fully biocompatible and promotes cellular attachment. The structure and sophisticated architecture of collagen type II is left intact.This chapter provides a comprehensive guide to the steps and reagents needed to decellularize articular cartilage. In addition to the standard decell-deGAG protocol, a fast option is given which is suitable for thin specimen. Histological evaluation is presented to illustrate treatment success.


Assuntos
Cartilagem Articular , Humanos , Tecidos Suporte/química , Engenharia Tecidual/métodos , Ácido Clorídrico , Matriz Extracelular/química
10.
Methods Mol Biol ; 2598: 313-323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36355301

RESUMO

The goal of a self-assembly tissue engineering is to create functional tissue following a natural cell-driven process that mirrors natural development. This approach to tissue engineering has tremendous potential for the development of reparative strategies to treat musculoskeletal injuries and diseases, especially for articular cartilage which has poor regenerative capacity. Additionally, many bioengineering and culture methods fail to maintain the chondrocyte phenotype and contain the correct matrix composition in the long term. Existing cartilage-engineering approaches have been developed, but many approaches involve complicated culture techniques and require foreign substances and biomaterials as scaffolds. While these scaffold-based approaches have numerous advantages, such as an instant or rapid creation of biomechanical properties, they frequently result in dedifferentiation of cells in part, due to the adherence to foreign scaffold materials. In this chapter, we describe a novel approach of developing a scaffold-less cartilage-like biomaterial, using the simple principle that cells at high density bear a capacity to coalesce when they cannot attach to any culture substrate. We refer to the biomaterial formed as a cartilage tissue equivalent or CTA and have published to describe their characteristics and utility in high-throughput drug screening. The method is described to generate reproducible cartilage analogs using a specialized high-density suspension culture technique using a hydrogel poly-2-hydroxyethyl methacrylate (polyHEMA) coating of a culture dish. We have demonstrated that this approach can rapidly form biomass of chondrocytes that over time becomes very synthetically active producing a cartilage-like extracellular matrix that closely mimics the biochemical and biomechanical characteristics of native articular cartilage. The culture approach can also be used to form CTA from other than articular cartilage-derived chondrocytes as well as mesenchymal stem cells (MSCs) (while differentiating MSCs into chondrocytes). Some of the advantages are phenotype stability, reproducible CTA size, and biomechanical and biochemical characteristics similar to natural cartilage.


Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Engenharia Tecidual/métodos , Condrócitos , Materiais Biocompatíveis/farmacologia , Tecidos Suporte/química , Condrogênese
11.
Colloids Surf B Biointerfaces ; 221: 112958, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36327774

RESUMO

The development of highly porous cell supportive polymeric scaffolds with sufficient mechanical strength has always been a challenging task in tissue engineering. The widely used nanofiber fabrication methods like electrospinning are time consuming and the obtained nanofibrous scaffolds are generally consist of compactly packed fibers, which affect proper cell penetration. On the other hand, air-jet spinning is an upcoming, less explored alternative approach for generating loosely arranged nanofibrous scaffolds within short time. However, air-jet spun scaffolds show inferior mechanical properties due to loosely organized fibers. Herein, we report the fabrication and detailed characterization of polycaprolactone (PCL) tissue engineering scaffolds loaded with diamond nanosheets (DNS) by air-jet spinning. Our results showed that the inclusion of DNS could improve the mechanical strength of the scaffolds. In vitro biocompatibility, and in vivo implantation studies demonstrated that PCL-DNS scaffolds are highly biocompatible and are suitable for tissue engineering applications. Our studies showed that mammalian cells can proliferate well in the presence of PCL-DNS scaffolds and the nanocomposite scaffolds implanted in rats did not show any considerable adverse effects. Overall, the findings show that the developed novel air-jet spun PCL-DNS nanocomposite scaffolds can be used as cell supportive scaffolds for various tissue engineering applications.


Assuntos
Nanocompostos , Nanofibras , Ratos , Animais , Engenharia Tecidual/métodos , Diamante , Tecidos Suporte , Poliésteres , Mamíferos
12.
J Mech Behav Biomed Mater ; 137: 105524, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36332397

RESUMO

This work is dedicated to combining nanotechnology with bone tissue engineering to prepare and characterize electrospun gelatin/monetite nanofibrous scaffold with improved physicochemical, mechanical, and biological properties. Nanofibrous scaffolds possessing fiber diameter in the range of 242-290 nm were prepared after incorporating varying content of monetite nanoparticles up to 7 wt % into the gelatin matrix using the electrospinning technique. Cross-linking of gelatin chains in the scaffold was performed using 0.25 wt% glutaraldehyde as indicated by imine (-CN-) bond formation in the FTIR analysis. With an increase in monetite addition up to 7 wt%, a decrease in swelling ratio and bio-degradability of cross-linked gelatin scaffolds was observed. Gelatin scaffold with 7 wt% monetite content registered the highest values of tensile strength and tensile modulus of 18.8 MPa and 170 MPa, as compared to 0% and 5 wt% monetite containing scaffolds respectively. Cell viability and differentiation were studied after culturing MG-63 cells onto the scaffolds from confocal microscopy of live and dead cells images, MTT assay, and alkaline phosphatase assay for a cell culture period of up to 21 days. It was observed that 7 wt % monetite containing gelatin scaffold exhibited better MG-63 cell adhesion, proliferation, higher biomineralization, and ALP activity compared to 0% and 5 wt% monetite containing electrospun scaffolds studied here.


Assuntos
Gelatina , Nanofibras , Gelatina/química , Tecidos Suporte/química , Engenharia Tecidual/métodos , Fosfatos de Cálcio , Nanofibras/química , Proliferação de Células
13.
Colloids Surf B Biointerfaces ; 221: 112929, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334516

RESUMO

Peripheral nerve injury (PNI) is the leading cause of permanent dysfunction in movement and sensation. Despite the rapid development of tissue engineering in peripheral nerve regeneration, autograft remains the gold standard for treating PNI. Synthesized nerve guidance conduits (NGCs) were reported as a potential alternative treatment that could replace autograft. However, most current NGCs are hollow tubular structured, or NGCs with macro or microstructures, but not both. These simple structures could not meet the need for neurite and Schwann cell guidance and accelerate peripheral nerve regeneration. In the current study, we combine unidirectional freezing with electrospinning to produce a unique NGC with longitudinal microchannels and parallel nanofibers. The in vitro study showed the importance of having both features in promoting Schwann cell growth, migration, and PC-12 cells neurite elongation. The novel NGCs could provide desirable physical support and guidance for peripheral nerve regeneration. From the current study, we found both the micro feature and the nano feature are helpful in terms of helping cell migrating through the NGCs, and the combination of both features will have a syngeneic effect.


Assuntos
Quitosana , Nanofibras , Nanofibras/química , Quitosana/farmacologia , Neuritos , Regeneração Nervosa , Células de Schwann , Tecidos Suporte/química
14.
Methods Mol Biol ; 2575: 127-152, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36301474

RESUMO

The low regenerative potential of the human body hinders proper regeneration of dysfunctional or lost tissues and organs due to trauma, congenital defects, and diseases. Tissue or organ transplantation has hence been a major conventional option for replacing the diseased or dysfunctional body parts of the patients. In fact, a great number of patients on waiting lists would benefit tremendously if tissue and organs could be replaced with biomimetic spare parts on demand. Herein, regenerative medicine and advanced biomaterials strive to reach this distant goal. Tissue engineering aims to create new biological tissue or organ substitutes, and promote regeneration of damaged or diseased tissue and organs. This approach has been jointly evolving with the major advances in biomaterials, stem cells, and additive manufacturing technologies. In particular, three-dimensional (3D) bioprinting utilizes 3D printing to fabricate viable tissue-like structures (perhaps organs in the future) using bioinks composed of special hydrogels, cells, growth factors, and other bioactive contents. A third generation of multifunctional biomaterials could also show opportunities for building biomimetic scaffolds, upon which to regenerate stem cells in vivo. Besides, decellularization technology based on isolation of extracellular matrix of tissue and organs from their inhabiting cells is presented as an alternative to synthetic biomaterials. Today, the gained knowledge of functional microtissue engineering and biointerfaces, along with the remarkable advances in pluripotent stem cell technology, seems to be instrumental for the development of more realistic microphysiological 3D in vitro tissue models, which can be utilized for personalized disease modeling and drug development. This chapter will discuss the recent advances in the field of regenerative medicine and biomaterials, alongside challenges, limitations, and potentials of the current technologies.


Assuntos
Bioimpressão , Células-Tronco Pluripotentes , Humanos , Medicina Regenerativa/métodos , Materiais Biocompatíveis/química , Engenharia Tecidual/métodos , Impressão Tridimensional , Tecidos Suporte
15.
Methods Mol Biol ; 2575: 269-274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36301480

RESUMO

For decades, scientists and physicians aim to generate functional human tissues in the laboratory using stem cells. In this section, we will describe a novel method that combines state-of-the-art stem cell culture with 3D bioprinting to generate potentially transplantable tissue grafts. For this purpose, we will use the liver as a model. The liver is an important metabolic hub and responsible to perform many endocrine and exocrine vital functions. It is estimated that two million deaths/year are associated with liver disease. This illustrates the need for developing new efficient alternatives for liver transplantation. Modern 3D bioprinting technologies in combination with autologous induced pluripotent stem cells (iPS)-derived grafts could represent a relevant tissue engineering approach to treat end-stage liver disease. Here, we described a novel method for 3D bioprinting functional and stable liver grafts using human iPS-derived cells. The novel method described in this section uses the hepatocyte-like cells in a spheroid culture format (i.e., obtained from three-dimensional cell culture), in combination or not with non-parenchymal cells (e.g., mesenchymal and endothelial cells), which generates the final liver graft. This method has proved to sustain epithelial phenotype and to increase the stability and functionality of the constructs for prolonged periods.


Assuntos
Bioimpressão , Células-Tronco Pluripotentes Induzidas , Transplante de Fígado , Humanos , Bioimpressão/métodos , Células Endoteliais , Impressão Tridimensional , Engenharia Tecidual/métodos , Fígado , Tecidos Suporte
16.
J Biomed Mater Res B Appl Biomater ; 111(1): 62-72, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35822935

RESUMO

Regenerative bio-scaffolds, widely used for clinical tissue reconstruction and tissue repairs, are functionally diversified and structurally complex decellularized tissue materials (e.g., extracellular matrix, ECM). ECM is naturally cross-linked and can be further selectively cross-linked upon processing. Identification, quantification and bioinformatics functional comparison of all ECM proteins are challenging for regenerative bio-scaffolds. In this study, we have applied proteomic profiling with a two-step sequential trypsinization method, and identified and quantified 300-400 constituent proteins in three commercially available regenerative bio-scaffolds (BioDesign Surgisis, ReGen tissue matrix, and ThormalGEN mesh). These proteins were classified into four categories and 14 subcategories based on their mainly biological function. The main components of regenerative bio-scaffolds were highly abundant ECM structural proteins, and the minor parts of bio-scaffolds were lowly abundant, less cross-linked, functionally more diversified proteins, especially extracellular fluid proteins that were easily solubilized by trypsin. The comparative analysis has revealed large differences in the number, type, abundance and function of identified proteins, as well as the extent of decellularization and cross-linking among regenerative bio-scaffolds. So, the proteomic profiling with a two-step sequential trypsinization method could not only provide the molecular basis to better understand the degradation process of regenerative bio-scaffolds in vivo and different clinical outcomes among various regenerative bio-scaffolds, facilitate the exploration of the response mechanisms in the host's early clinical stages of ECM-induced tissue regeneration that is still poorly understood, but also can be used for optimization of the decellularization and cross-linking process, product characterization and rational design of new ECM products.


Assuntos
Proteômica , Tecidos Suporte , Tecidos Suporte/química , Proteômica/métodos , Matriz Extracelular/química , Proteínas da Matriz Extracelular/metabolismo , Engenharia Tecidual/métodos
17.
J Biomed Mater Res B Appl Biomater ; 111(1): 73-84, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35841326

RESUMO

Periodontal disease is a common disease in the oral field, and many researchers are studying periodontal disease and try to find some biological scaffold materials to make periodontal tissue regenerative. In this study, we attempted to construct a carbon nanotube/chitosan/sodium alginate (CNT/CS/AL) ternary composite hydrogel and then prepare porous scaffold by 3D printing technology. Subsequently, characterizing the materials and testing the mechanical properties of the scaffold. Additionally, its effect on the proliferation of human periodontal ligament cells (hPDLCs) and its antibacterial effect on Porphyromonas gingivalis were detected. We found that CNT/CS/AL porous composite scaffolds with uniform pores could be successfully prepared. Moreover, with increasing CNT concentration, the degradation rate and the swelling degree of scaffold showed a downward trend. The compressive strength test indicated the elastic modulus of composite scaffolds ranged from 18 to 80 kPa, and 1% CNT/CS/AL group had the highest quantitative value. Subsequently, cell experiments showed that the CNT/CS/AL scaffold had good biocompatibility and could promote the proliferation of hPDLCs. Among 0.1%-1% CNT/CS/AL groups, the biocompatibility of 0.5% CNT/CS/AL scaffold performed best. Meanwhile, in vitro antibacterial experiments showed that the CNT/CS/AL scaffold had a certain bacteriostatic effect on P. gingivalis. When the concentration of CNT was more than 0.5%, the antimicrobial activity of composite scaffold was significantly promoted, and about 30% bacteria were inactivated. In conclusion, this 3D-printed CNT/CS/AL composite scaffold, with good material properties, biocompatibility and bacteriostatic activity, may be used for periodontal tissue regeneration, providing a new avenue for the treatment of periodontal disease.


Assuntos
Quitosana , Nanotubos de Carbono , Doenças Periodontais , Humanos , Tecidos Suporte , Engenharia Tecidual , Alginatos , Impressão Tridimensional , Antibacterianos
18.
J Biomed Mater Res B Appl Biomater ; 111(1): 140-150, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35852036

RESUMO

The objective was to synthesize and characterize fine polycaprolactone (PCL) fibers associated with a new 58S bioglass obtained by the precipitated sol-gel route, produced by the electrospinning process in order to incorporate therapeutic ions (Mg and Li). In PCL/acetone solutions were added 7% pure bioglass, bioglass doped with Mg(NO3 )2 and Li2 CO3 and were subjected to electrospinning process. The fibers obtained were characterized morphologically, chemically and biologically. The results showed the presence of fine fibers at the nanometric scale and with diameters ranging from 0.67 to 1.92 µm among groups. Groups containing bioglass showed particles both inside and on the surface of the fibers. The components of the polymer, bioglass and therapeutic ions were present in the fibers produced. The produced fibers showed cell viability and induced the formation of mineralization nodules. It was observed the applicability of that methodology in making an improved biomaterial, which adds the osteoinductive properties of the bioglass to PCL and to those of therapeutic ions, applicable to guided bone regeneration.


Assuntos
Poliésteres , Tecidos Suporte , Tecidos Suporte/química , Poliésteres/química , Cerâmica/química , Materiais Biocompatíveis/química , Íons , Engenharia Tecidual/métodos
19.
J Biomed Mater Res B Appl Biomater ; 111(1): 85-94, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35852254

RESUMO

The in vitro reconstruction of the extracellular matrix (ECM) is required in tissue engineering and regenerative medicine because the ECM can regulate cell functions in vivo. For ECM reconstruction, a decellularization technique is used. ECM reconstructed by decellularization (dECM) is prepared from tissues/organs and cultured cells. Although decellularization methods have been optimized for tissue-/organ-derived dECM, the methods for cultured cell-derived dECM have not yet been optimized. Here, two physical (osmotic shocks) and five chemical decellularization methods are compared. The decellularization efficacies were changed according to the decellularization methods used. Among them, only the Triton X-100 and Tween 20 treatments could not decellularize completely. Additionally, when the efficacies were compared among different types of cells (monolayered cells with/without strong cell adhesion, multilayered cells), the efficacies were decreased for multilayered cells or cells with strong cell adhesion. Retained ECM contents tended to be greater in the dECM prepared by osmotic shocks than in those prepared by chemical methods. The contents impacted cell adhesion, shapes, growth and intracellular signal activation on the dECM. The comparison would be helpful for the optimization of decellularization methods for cultured cells, and it could also provide new insights into developing milder decellularization methods for tissues and organs.


Assuntos
Matriz Extracelular , Engenharia Tecidual , Matriz Extracelular/química , Engenharia Tecidual/métodos , Células Cultivadas , Linhagem Celular , Octoxinol/farmacologia , Tecidos Suporte/química
20.
J Biomed Mater Res B Appl Biomater ; 111(1): 161-172, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35906959

RESUMO

Natural proteins have been reported to positively affect the attachment and proliferation of cells. For the first time, zein, a plant protein, was utilized to make patterned surface mimicking the extracellular matrix to assist the attachment and proliferation of stem cells. Zein would promote the attachment and proliferation of the stem cells more than 10 times of that of gelatin and silk fibroin, respectively, which are popular protein selections for the formation of the biomaterial scaffolds. The more the surface was covered by zein, the more the stem cell grown. It was revealed that the stem cells would grow and stretch in the direction of the patterns, and the stem cells preferred to grow in the grooves in the size of 8 µm, that was similar to the size of the stem cells, rather than the size larger or smaller than that of the cells, such as 50 and 2 µm. It was concluded that zein is a better choice than silk fibroin and gelatin with highly potential for the formation of patterned surface and structure as the biomaterial scaffolds for stem cell therapy.


Assuntos
Fibroínas , Células-Tronco Mesenquimais , Zeína , Humanos , Fibroínas/química , Gelatina/química , Tecidos Suporte/química , Biomimética , Células-Tronco Mesenquimais/metabolismo , Proliferação de Células , Materiais Biocompatíveis/metabolismo , Seda/metabolismo , Engenharia Tecidual
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