RESUMO
BACKGROUND: Tissue engineering seeks to improve, maintain, or replace the biological functions of damaged organs or tissues with biological substitutes such as the development of scaffolds. In the case of bone tissue, they must have excellent mechanical properties like native bone. OBJECTIVE: In this work, three geometric models were designed for scaffolds with different structure lattices and porosity that could be biomechanically suitable and support cell growth for trabecular bone replacement applications in tissue engineering and regenerative medicine to the proximal femur area. METHODS: Geometries were designed using computer-aided design (CAD) software and evaluated using finite element analysis in compression tests. Three loads were considered according to the daily activity: 1177 N for slow walking, 2060 N for fast walking, and 245.25 N for a person in a bipedal position. All these loads for an adult weight of 75 kg. For each of them, three biomaterials were assigned: two polymers (poly-glycolic acid (PGA) and poly-lactic acid (PLA)) and one mineral (hydroxyapatite (HA)). 54 tests were performed: 27 for each of the tests. RESULTS: The results showed Young's modulus (E) between 1 and 4 GPa. CONCLUSION: If the resultant E is in the range of 0.1 to 5 GPa, the biomaterial is considered an appropriate alternative for the trabecular bone which is the main component of the proximal bone. However, for the models applied in this study, the best option is the poly-lactic acid which will allow absorbing the acting loads.
Assuntos
Desenho Assistido por Computador , Análise de Elementos Finitos , Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Humanos , Engenharia Tecidual/métodos , Durapatita/química , Módulo de Elasticidade , Bioimpressão/métodos , Poliésteres/química , Porosidade , Simulação por Computador , Materiais Biocompatíveis/química , Substitutos Ósseos/química , Ácido Poliglicólico/química , Impressão Tridimensional , Teste de Materiais , Osso e OssosRESUMO
3D in vitro systems offer advantages over the shortcomings of two-dimensional models by simulating the morphological and functional features of in vivo-like environments, such as cell-cell and cell-extracellular matrix interactions, as well as the co-culture of different cell types. Nevertheless, these systems present technical challenges that limit their potential in cancer research requiring cell line- and culture-dependent standardization. This protocol details the use of a magnetic 3D bioprinting method and other associated techniques (cytotoxicity assay and histological analysis) using oral squamous cell carcinoma cell line, HSC3, which offer advantages compared to existing widely used approaches. This protocol is particularly timely, as it validates magnetic bioprinting as a method for the rapid deployment of 3D cultures as a tool for compound screening and development of heterotypic cultures such as co-culture of oral squamous cell carcinoma cells with cancer-associated fibroblasts (HSC3/CAFs).
Assuntos
Bioimpressão , Carcinoma de Células Escamosas , Técnicas de Cocultura , Neoplasias Bucais , Impressão Tridimensional , Esferoides Celulares , Humanos , Neoplasias Bucais/patologia , Bioimpressão/métodos , Linhagem Celular Tumoral , Carcinoma de Células Escamosas/patologia , Técnicas de Cocultura/métodos , Esferoides Celulares/patologia , Técnicas de Cultura de Células em Três Dimensões/métodosRESUMO
3D-printed hydrogel scaffolds biomimicking the extracellular matrix (ECM) are key in cartilage tissue engineering as they can enhance the chondrogenic differentiation of mesenchymal stem cells (MSCs) through the presence of active nanoparticles such as graphene oxide (GO). Here, biomimetic hydrogels were developed by cross-linking alginate, gelatin, and chondroitin sulfate biopolymers in the presence of GO as a bioactive filler, with excellent processability for developing bioactive 3D printed scaffolds and for the bioprinting process. A novel bioink based on our hydrogel with embedded human MSCs presented a cell survival rate near 100% after the 3D bioprinting process. The effects of processing and filler concentration on cell differentiation were further quantitatively evaluated. The nanocomposited hydrogels render high MSC proliferation and viability, exhibiting intrinsic chondroinductive capacity without any exogenous factor when used to print scaffolds or bioprint constructs. The bioactivity depended on the GO concentration, with the best performance at 0.1 mg mL-1. These results were explained by the rational combination of the three biopolymers, with GO nanoparticles having carboxylate and sulfate groups in their structures, therefore, biomimicking the highly negatively charged ECM of cartilage. The bioactivity of this biomaterial and its good processability for 3D printing scaffolds and 3D bioprinting techniques open up a new approach to developing novel biomimetic materials for cartilage repair.
Assuntos
Alginatos , Bioimpressão , Diferenciação Celular , Condrogênese , Sulfatos de Condroitina , Gelatina , Hidrogéis , Células-Tronco Mesenquimais , Nanocompostos , Impressão Tridimensional , Alicerces Teciduais , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Alginatos/química , Alginatos/farmacologia , Gelatina/química , Bioimpressão/métodos , Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Nanocompostos/química , Alicerces Teciduais/química , Hidrogéis/química , Hidrogéis/farmacologia , Engenharia Tecidual/métodos , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Grafite/química , Grafite/farmacologia , Proliferação de Células/efeitos dos fármacos , Células CultivadasRESUMO
Inherited and non-inherited retinopathies can affect distinct cell types, leading to progressive cell death and visual loss. In the last years, new approaches have indicated exciting opportunities to treat retinopathies. Cell therapy in retinitis pigmentosa, age-related macular disease, and glaucoma have yielded encouraging results in rodents and humans. The first two diseases mainly impact the photoreceptors and the retinal pigmented epithelium, while glaucoma primarily affects the ganglion cell layer. Induced pluripotent stem cells and multipotent stem cells can be differentiated in vitro to obtain specific cell types for use in transplant as well as to assess the impact of candidate molecules aimed at treating retinal degeneration. Moreover, stem cell therapy is presented in combination with newly developed methods, such as gene editing, Müller cells dedifferentiation, sheet & drug delivery, virus-like particles, optogenetics, and 3D bioprinting. This review describes the recent advances in this field, by presenting an updated panel based on cell transplants and related therapies to treat retinopathies.
Assuntos
Bioimpressão , Glaucoma , Transplante de Células-Tronco Hematopoéticas , Degeneração Retiniana , Humanos , Edição de Genes/métodos , Degeneração Retiniana/genética , Degeneração Retiniana/terapia , Transplante de Células-Tronco/métodosRESUMO
For the past few years, three-dimensional (3D) bioprinting has emerged as a promising approach in the field of regenerative medicine. This technique allows for the production of 3D scaffolds to support cell transplantation due to its ability to mimic the extracellular environment. One alternative to enhancing cell adhesion, survival, and proliferation is the use of decellularized extracellular matrix as a bioink component. The aim of this study was to produce a bioink using lyophilized rat decellularized spinal cord tissue (DSCT) for 3D bioprinting of nervous tissue. DNA quantification, hematoxylin and eosin and DAPI staining indicated that 1% sodium dodecyl sulfate and 9 h processing were effective in removing the cells from the spinal cord samples. The cell viability assay showed that the decellularized matrix is not cytotoxic for PC12 cells. The hydrogel containing DSCT, alginate, and gelatine used as the base for the bioink has a shear thinning behavior and low Gâ³/G' ratio, allowing for good printability without compromising cell viability after 3D bioprinting. The bioink supported long-term PC12 cell survival, with 93% of live cells 4 weeks after printing, and stimulated the production of laminin-1 and neurofilament-M. This bioink, therefore, represents an easily available biomaterial for central nervous system tissue engineering.
Assuntos
Bioimpressão , Alicerces Teciduais , Ratos , Animais , Bioimpressão/métodos , Matriz Extracelular/metabolismo , Engenharia Tecidual/métodos , Medula Espinal , Impressão TridimensionalRESUMO
Introducción: Las fracturas complejas de fémur distal AO/AOT tipo 33C3.3 constituyen un reto para los ortopedistas debido a la dificultad de su tratamiento y las complicaciones asociadas. El planeamiento y procedimiento quirúrgicos emplean placas condilares, pero estas se asocian a la pérdida de la fijación y al colapso de la reducción. Objetivo: Describir la planificación preoperatoria de una fractura de fémur distal AO/AOT 33C3.3 con bioimpresión 3D y reconstrucción por computadora. Presentación del caso: Paciente masculino de 34 años con fractura izquierda conminuta del fémur distal, AO/AOT tipo 33C3.3, por un accidente de tránsito. El planeamiento y el tratamiento quirúrgicos se realizaron exitosamente con la impresión y reconstrucción de biomodelos 3D. Basados en las imágenes tomográficas del paciente, se identificaron los principales fragmentos, la secuencia de reducción, la cantidad y la posición de los implantes a utilizar. Conclusiones: La planificación preoperatoria resulta una etapa de vital importancia en el manejo de fracturas complejas. Las técnicas convencionales pueden optimizarse con la cirugía asistida por computadora y reconstrucción con biomodelos 3D impresos. Esta novedosa propuesta permitirá el adecuado uso de materiales, una óptima secuencia de reducción, mejor estabilidad de la fractura y menor riesgo de complicaciones quirúrgicas(AU)
Introduction: Complex distal femur fractures AO/AOT type 33C3.3 constitute a challenge for orthopedists due to the difficulty of their treatment and associated complications. The surgical planning and procedure use condylar plates; but these are associated with loss of fixation and collapse of the reduction. Objective: To describe preoperative planning for an AO/AOT 33C3.3 distal femur fracture with 3D bioprinting and computer reconstruction. Case report: The case of a 34-year-old male patient is reported. He has comminuted left fracture of the distal femur, AO/AOT type 33C3.3, due to a traffic accident. Surgical planning and treatment were successfully performed with 3D biomodel printing and reconstruction. Based on the patient's tomographic images, the main fragments, the reduction sequence, the number and position of the implants to be used were identified. Conclusions: Preoperative planning is a critically important stage in managing complex fractures. Conventional techniques can be optimized with computer-assisted surgery and reconstruction with 3D printed biomodels. This novel proposal will allow the appropriate use of materials, optimal reduction sequence, better stability of the fracture and lower risk of surgical complications(AU)
Assuntos
Humanos , Masculino , Adulto , Acidentes de Trânsito , Cirurgia Assistida por Computador/instrumentação , Fraturas do Fêmur/cirurgia , Bioimpressão/métodos , PlanejamentoRESUMO
In December 2019, COVID-19 emerged in China, and in January 2020, the World Health Organization declared a state of international emergency. Within this context, there is a significant search for new drugs to fight the disease and a need for in vitro models for preclinical drug tests. This study aims to develop a 3D lung model. For the execution, Wharton's jelly mesenchymal stem cells (WJ-MSC) were isolated and characterized through flow cytometry and trilineage differentiation. For pulmonary differentiation, the cells were seeded in plates coated with natural functional biopolymer matrix as membrane until spheroid formation, and then the spheroids were cultured with differentiation inductors. The differentiated cells were characterized using immunocytochemistry and RT-PCR, confirming the presence of alveolar type I and II, ciliated, and goblet cells. Then, 3D bioprinting was performed with a sodium alginate and gelatin bioink in an extrusion-based 3D printer. The 3D structure was analyzed, confirming cell viability with a live/dead assay and the expression of lung markers with immunocytochemistry. The results showed that the differentiation of WJ-MSC into lung cells was successful, as well as the bioprinting of these cells in a 3D structure, a promising alternative for in vitro drug testing.
Assuntos
Bioimpressão , COVID-19 , Geleia de Wharton , Humanos , COVID-19/metabolismo , Células Cultivadas , Diferenciação Celular , Impressão Tridimensional , Engenharia TecidualRESUMO
Currently, the only feasible option for patients with progressive and/or end-stage organ degeneration is to undergo transplantation. Due to the growing unmatched demand of available organ donors and, as a consequence, the continuous growth of patients' waiting lists, the development of new tissue engineering technologies is a relevant need. In this chapter, we will focus on the liver as a model organ to discuss contemporary tissue engineering strategies. Induced pluripotent cells are an attractive alternative to serve as a cell source for tissue engineering applications due to their pluripotency, the potentiality to generate autologous transplantation, and for their high proliferation rate. Among the main liver tissue engineering technologies, 3D bioprinting, hepatic organoids, and decellularization/recellularization of biological matrixes have grown much attention as alternatives to derive functional liver grafts. Thus, this chapter will discuss how recent publications have demonstrated the use of induced pluripotent cells in the development of the aforementioned technologies. Bioprinting is an additive manufacturing biofabrication process where cells are dispersed within a matrix formulation (i.e., bioink) and extruded in a modified 3D-printer. Polymers within bioink can be cross-linked to increase stiffness. Hepatic spheroids showed greater viability and liver function, due to preserved epithelial phenotype over time. Organoid is multi-lineage tissue constructs derived from a stem cell that recapitulates the early stages of organogenesis. The influence of cellular composition of non-parenchymal cells using induced pluripotent-derived cells or primary adult cells for hepatic organoid formation was recently tested. Decellularization is a process where harvested tissues or organs are washed with a detergent-based solution, to lyse and remove all cellular components. The final product is an extracellular scaffold with preserved tissue vasculature and ultra-structure, which can be used for subsequent recellularization with recipient cells. This chapter sheds light on recent works on the use of induced pluripotent-derived cells for liver tissue engineering approaches and on how such technologies could potentially generate therapeutic alternatives for patients on waiting lists for liver transplantation.
Assuntos
Proliferação de Células , Hepatócitos , Células-Tronco , Engenharia Tecidual , Bioimpressão , Proliferação de Células/fisiologia , Hepatócitos/fisiologia , Transplante de Órgãos , Impressão Tridimensional , Células-Tronco/fisiologia , Tecnologia , Engenharia Tecidual/métodosRESUMO
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 , Alicerces TeciduaisRESUMO
The increasing demand for tissue replacement has encouraged scientists worldwide to focus on developing new biofabrication technologies. Multimaterials/cells printed with stringent resolutions are necessary to address the high complexity of tissues. Advanced inkjet 3D printing can use multimaterials and attain high resolution and complexity of printed structures. However, a decisive yet limiting aspect of translational 3D bioprinting is selecting the befitting material to be used as bioink; there is a complete lack of cytoactive bioinks with adequate rheological, mechanical, and reactive properties. This work strives to achieve the right balance between resolution and cell support through methacrylamide functionalization of a psychrophilic gelatin and new fluorosurfactants used to engineer a photo-cross-linkable and immunoevasive bioink. The syntonized parameters following optimal formulation conditions allow proficient printability in a PolyJet 3D printer comparable in resolution to a commercial synthetic ink (â¼150 µm). The bioink formulation achieved the desired viability (â¼80%) and proliferation of co-printed cells while demonstrating in vivo immune tolerance of printed structures. The practical usage of existing high-resolution 3D printing systems using a novel bioink is shown here, allowing 3D bioprinted structures with potentially unprecedented complexity.