RESUMO
Tissue engineering using cardiomyocytes derived from human pluripotent stem cells holds a promise to revolutionize drug discovery, but only if limitations related to cardiac chamber specification and platform versatility can be overcome. We describe here a scalable tissue-cultivation platform that is cell source agnostic and enables drug testing under electrical pacing. The plastic platform enabled on-line noninvasive recording of passive tension, active force, contractile dynamics, and Ca2+ transients, as well as endpoint assessments of action potentials and conduction velocity. By combining directed cell differentiation with electrical field conditioning, we engineered electrophysiologically distinct atrial and ventricular tissues with chamber-specific drug responses and gene expression. We report, for the first time, engineering of heteropolar cardiac tissues containing distinct atrial and ventricular ends, and we demonstrate their spatially confined responses to serotonin and ranolazine. Uniquely, electrical conditioning for up to 8 months enabled modeling of polygenic left ventricular hypertrophy starting from patient cells.
Assuntos
Miócitos Cardíacos/citologia , Técnicas de Cultura de Tecidos/instrumentação , Engenharia Tecidual/métodos , Potenciais de Ação , Diferenciação Celular , Células Cultivadas , Fenômenos Eletrofisiológicos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Biológicos , Miocárdio/citologia , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes/citologia , Técnicas de Cultura de Tecidos/métodosRESUMO
The development of epithelial lumens in ducts is essential to the functioning of various organs and in organogenesis. Ductal elongation requires the collective migration of cell cohorts in three-dimensional (3D) confined spaces, while maintaining their epithelial integrity. Epithelial lumens generally adopt circular morphologies, however abnormalities in complex physiological environments can lead to the narrowing of glandular spaces that adopt elongated and slit-like morphologies. Here, we describe a simple method to form epithelial tissues in microchannels of various widths (100-300 µm) with a constant height of 25 µm that mimic elongated geometries of glandular spaces. The significance of this biomimetic platform has been evidenced by studying the migration of epithelial cell sheets inside these narrow slits of varying dimensions. We show that the growth of epithelial tissues in 3D-confined slits leads to a gradient of cell density along the slit axis and that the migration cell velocity depends on the extent of the spatial confinement. Our findings indicate that nuclear orientation is higher for leader cells and depends on the slit width, whereas YAP protein was predominantly localized in the nucleus of leader cells. This method will pave the way to studies aiming at understanding how 3D-confined spaces, which are reminiscent of in vivo pathological conditions, can affect the growth and the homeostasis of epithelial tissues.
Assuntos
Movimento Celular/fisiologia , Epitélio/metabolismo , Microtecnologia/instrumentação , Técnicas de Cultura de Tecidos , Animais , Núcleo Celular/metabolismo , Cães , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Desenho de Equipamento , Células Madin Darby de Rim Canino , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodosRESUMO
Cultured skin has been used extensively for testing therapeutic drugs because it replicates the physical and biochemical properties of whole skin. However, traditional static culture cannot fully maintain cell viability and skin morphology because of the limitations involved with nutrient transmission. Here, we develop a new dynamic perfusion platform for skin culture and compare it with a static culture device. Rat skins were cultured in either static or dynamic condition for 0, 3, 6, 9 and 12 days. H&E, periodic acid-Schiff (PAS) and picrosirius red (PSR) staining were used for skin morphology detection, immunostaining against cytokeratin 10 (CK10) for differentiation detection, immunostaining against proliferating cell nuclear antigen (PCNA) for cell proliferation detection and TUNEL staining for apoptosis detection. After culturing for 12 days, the epidermis, basement membrane, hair follicles and connective tissue were disrupted in the static group, whereas these features were preserved in the dynamic group. Moreover, compared to the static group, proliferation in the epidermis and hair follicles was significantly improved and apoptosis in dermis was significantly decreased in the dynamic group. These findings suggest that our device is effective for extending the culture period of rat skin to maintain its characteristics and viability in vitro.
Assuntos
Pele/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodos , Animais , Apoptose , Proliferação de Células , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Sprague-Dawley , Pele/anatomia & histologia , Pele/citologia , Coloração e RotulagemRESUMO
BACKGROUND: Though the management of malignancies has improved vastly in recent years, many treatment options lack the desired efficacy and fail to adequately augment patient morbidity and mortality. It is increasingly clear that patient response to therapy is unique to each individual, necessitating personalised, or 'precision' medical care. This demand extends to thyroid cancer; ~ 10% patients fail to respond to radioiodine treatment due to loss of phenotypic differentiation, exposing the patient to unnecessary ionising radiation, as well as delaying treatment with alternative therapies. METHODS: Human thyroid tissue (n = 23, malignant and benign) was live-sliced (5 mm diameter × 350-500 µm thickness) then analysed or incorporated into a microfluidic culture device for 96 h (37 °C). Successful maintenance of tissue was verified by histological (H&E), flow cytometric propidium iodide or trypan blue uptake, immunohistochemical (Ki67 detection/ BrdU incorporation) and functional analysis (thyroxine [T4] output) in addition to analysis of culture effluent for the cell death markers lactate dehydrogenase (LDH) and dead-cell protease (DCP). Apoptosis was investigated by Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL). Differentiation was assessed by evaluation of thyroid transcription factor (TTF1) and sodium iodide symporter (NIS) expression (western blotting). RESULTS: Maintenance of gross tissue architecture was observed. Analysis of dissociated primary thyroid cells using flow cytometry both prior to and post culture demonstrated no significant change in the proportion of viable cells. LDH and DCP release from on-chip thyroid tissue indicated that after an initial raised level of release, signifying cellular damage, detectable levels dropped markedly. A significant increase in apoptosis (p < 0.01) was observed after tissue was perfused with etoposide and JNK inhibitor, but not in control tissue incubated for the same time period. No significant difference in Ki-67 positivity or TTF1/NIS expression was detected between fresh and post-culture thyroid tissue samples, moreover BrdU positive nuclei indicated on-chip cellular proliferation. Cultured thyroid explants were functionally viable as determined by production of T4 throughout the culture period. CONCLUSIONS: The described microfluidic platform can maintain the viability of thyroid tissue slices ex vivo for a minimum of four days, providing a platform for the assessment of thyroid tissue radioiodine sensitivity/adjuvant therapies in real time.
Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/instrumentação , Dispositivos Lab-On-A-Chip , Técnicas de Cultura de Tecidos/instrumentação , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/patologiaRESUMO
The folding and three-dimensional (3D) organization of chromatin in the nucleus critically impacts genome function. The past decade has witnessed rapid advances in genomic tools for delineating 3D genome architecture. Among them, chromosome conformation capture (3C)-based methods such as Hi-C are the most widely used techniques for mapping chromatin interactions. However, traditional Hi-C protocols rely on restriction enzymes (REs) to fragment chromatin and are therefore limited in resolution. We recently developed DNase Hi-C for mapping 3D genome organization, which uses DNase I for chromatin fragmentation. DNase Hi-C overcomes RE-related limitations associated with traditional Hi-C methods, leading to improved methodological resolution. Furthermore, combining this method with DNA capture technology provides a high-throughput approach (targeted DNase Hi-C) that allows for mapping fine-scale chromatin architecture at exceptionally high resolution. Hence, targeted DNase Hi-C will be valuable for delineating the physical landscapes of cis-regulatory networks that control gene expression and for characterizing phenotype-associated chromatin 3D signatures. Here, we provide a detailed description of method design and step-by-step working protocols for these two methods.
Assuntos
Mapeamento Cromossômico/métodos , Desoxirribonuclease I/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Imageamento Tridimensional/métodos , Imagem Molecular/métodos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatina/química , Cromatina/genética , Mapeamento Cromossômico/instrumentação , Reagentes de Ligações Cruzadas/química , Enzimas de Restrição do DNA/química , Enzimas de Restrição do DNA/metabolismo , Desoxirribonuclease I/química , Formaldeído/química , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Imageamento Tridimensional/instrumentação , Imagem Molecular/instrumentação , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodos , Sequenciamento Completo do Genoma/instrumentação , Sequenciamento Completo do Genoma/métodosRESUMO
Three-dimensional tissue cultures are important models for the study of cell-cell and cell-matrix interactions, as well as, to investigate tissue repair and reconstruction pathways. Therefore, we designed a reproducible and easy to handle printable bioreactor system (Teburu), that is applicable for different approaches of pathway investigation and targeted tissue repair using human tissue slices as a three-dimensional cell culture model. Here, we definitively describe Teburu as a controlled environment to reseed a 500-µm thick decellularized human liver slice using human mesenchymal stroma cells. During a cultivation period of eight days, Teburu, as a semi-open and low consumption system, was capable to maintain steady pH and oxygenation levels. Its combination with additional modules delivers an applicability for a wide range of tissue engineering approaches under optimal culture conditions.
Assuntos
Bioimpressão , Reatores Biológicos , Impressão Tridimensional , Técnicas de Cultura de Tecidos/instrumentação , Desenho de Equipamento , Humanos , Fígado/química , Fígado/citologia , Fígado/ultraestrutura , Engenharia Tecidual/instrumentação , Alicerces Teciduais/químicaRESUMO
BACKGROUND: Injuries in the musculoskeletal system, such as tendon and ligament ruptures, are challenging to manage and often require surgical reconstructions with limited long-term success. Thus, characterizations of these tissues are urgently needed to better understand cellular mechanisms that regulate tissue homeostasis and healing. Explant culturing systems allow for ex vivo analysis of tissues in an environment that mimics the native microenvironment in vivo. METHODS: Collaborative efforts within our institution facilitated the establishment of a novel explant culturing system. Tissue specimens cultured in single wells, with individual applied loading and/or biological environment, allowed characterization of tissue cultured under a variety of biological loading conditions. Quantitative PCR analysis for selected gene markers was our primary outcome. RESULTS: Data were stratified for analysis by either culture environment or loading condition. Our gene expression results show that specimens clustered by culture condition may differ in molecular markers related to ECM production (e.g., Col1a1, Adamts4) and/or organization (e.g., Tnc, Dnc). In contrast, loading condition did significantly alter the median gene expression levels of tissues in comparison to unloaded control samples, although gene expression values related to ECM degradation (e.g., Mmp1, Mmp10) were altered in tendons cultured under tension in the device. CONCLUSION: Our study demonstrates promising utility of a novel explant culturing system for further characterization of musculoskeletal tissues such as native tendons and ligaments, as well as pathologic fibrotic tissues resulting from arthrofibrosis or Dupuytren's disease.
Assuntos
Tendões/fisiologia , Técnicas de Cultura de Tecidos/instrumentação , Engenharia Tecidual/instrumentação , Animais , Fenômenos Biomecânicos , Desenho de Equipamento , Regulação da Expressão Gênica , Coelhos , Tendões/cirurgia , Resistência à Tração , Suporte de CargaRESUMO
BACKGROUND: The purpose of this meta-analysis was to evaluate the diagnostic accuracy of periprosthetic tissue culture in blood culture bottles (BCB) for periprosthetic joint infection (PJI). METHODS: PubMed, Web of Science, and Embase were systematically searched for eligible studies evaluating the diagnostic performance of periprosthetic tissue culture in BCB for the diagnosis of PJI. The pooled data were analysed by Meta-Disc software. RESULTS: Four studies with a total of 1071 patients were included in this meta-analysis. The summarized estimates showed that periprosthetic tissue culture in BCB may be of great value in PJI diagnosis with a pooled sensitivity of 0.70 (95% confidence interval [CI]; 0.66-0.75), specificity of 0.97 (95% CI: 0.95-0.98); positive likelihood ratio (PLR) of 20.98 (95% CI: 11.52-38.2); negative likelihood ratio (NLR) of 0.28 (95% CI: 0.20-0.40); and diagnostic odds ratio (DOR) of 92.26 (95% CI: 43.93-193.78). CONCLUSIONS: The present meta-analysis showed that periprosthetic tissue in BCB improves the results of microorganism cultures, with a sensitivity of 70% and a specificity of 97%. However, more large-scale, well-performed studies are needed to verify our findings.
Assuntos
Bactérias/isolamento & purificação , Técnicas Bacteriológicas/instrumentação , Infecções Relacionadas à Prótese/diagnóstico , Técnicas de Cultura de Tecidos/instrumentação , Técnicas Bacteriológicas/métodos , Hemocultura/instrumentação , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Infecções Relacionadas à Prótese/microbiologia , Sensibilidade e Especificidade , Técnicas de Cultura de Tecidos/métodosRESUMO
The viability of cartilage explants preserved in vitro decreases with time, which limits its use for transplantation. The effect of mechanical stimulation to cartilage explants in vitro is unknown. In this study, we observed the effects of mechanical stimulation on chondrocyte viability and the mechanical properties of cartilage explants preserved in vitro using a rolling-sliding loading device designed by us, and the optimal stimulation protocol was established. A cylindrical osteochondral mass drilled on the femoral condyle of a healthy pig was divided into two groups (loading group and control group), and changes in the chondrocyte survival rate, matrix composition and cartilage biomechanical properties was observed at different time points. Additionally, the mRNA expression of the apoptosis-related proteins caspase-3/Bax/Bcl-2, the cytoskeletal proteins actin/vimentin, and the matrix-related protein MMP13 were detected. The loading group exhibited delayed collagen and aggrecan degeneration and improved chondrocyte viability for three days. Protein and mRNA detection showed that apoptotic factors such as caspase-3 and Bax decreased rapidly in cartilage tissue after loading. The cytoskeletal proteins actin and vimentin showed no significant changes in mRNA expression in the control group, but was significantly higher in the loading group. MMP-13 mRNA expression was significantly higher in both the control group and loading group. Overall, this study suggests that suitable mechanical stimulation decreases the loss of chondrocyte viability and the mechanical properties of cartilage explants in vitro and improves cartilage preservation.
Assuntos
Cartilagem Articular/citologia , Condrócitos/citologia , Técnicas de Cultura de Tecidos/instrumentação , Animais , Apoptose , Fenômenos Biomecânicos , Sobrevivência Celular , Células Cultivadas , Desenho de Equipamento , Pressão , Estresse Mecânico , SuínosRESUMO
Biocompatible platforms, wherein cells attach and grow, are important for controlling cytoskeletal dynamics and steering stem cell functions, including differentiation. Among various components, membrane integrins play a key role in focal adhesion of cells (18-20 nm in size) and are, thus, highly sensitive to the nanotopographical features of underlying substrates. Hence, it is necessary to develop a platform/technique that can provide high flexibility in controlling nanostructure sizes. We report a platform modified with homogeneous nanohole patterns, effective in guiding neurogenesis of mouse neural stem cells (mNSCs). Sizes of nanoholes were easily generated and varied using laser interference lithography (LIL), by changing the incident angles of light interference on substrates. Among three different nanohole patterns fabricated on conductive transparent electrodes, 500 nm-sized nanoholes showed the best performance for cell adhesion and spreading, based on F-actin and lamellipodia/filopodia expression. Enhanced biocompatibility and cell adhesion of these nanohole patterns ultimately resulted in the enhanced neurogenesis of mNSCs, based on the mRNAs expression level of the mNSCs marker and several neuronal markers. Therefore, platforms modified with homogeneous nanohole patterns fabricated by LIL are promising for the precise tuning of nanostructures in tissue culture platforms and useful for controlling various differentiation lineages of stem cells.
Assuntos
Células-Tronco Neurais/citologia , Neurogênese , Técnicas de Cultura de Tecidos/instrumentação , Actinas/metabolismo , Animais , Adesão Celular , Diferenciação Celular , Células Cultivadas , Camundongos , Nanoestruturas , Células-Tronco Neurais/metabolismo , Tamanho da Partícula , Pseudópodes/metabolismoRESUMO
We have previously demonstrated that culturing periprosthetic tissue in blood culture bottles (BCBs) improves sensitivity compared to conventional agar and broth culture methods for diagnosis of prosthetic joint infection (PJI). We have also shown that prosthesis sonication culture improves sensitivity compared to periprosthetic tissue culture using conventional agar and broth methods. The purpose of this study was to compare the diagnostic accuracy of tissue culture in BCBs (subsequently referred to as tissue culture) to prosthesis sonication culture (subsequently referred to as sonicate fluid culture). We studied 229 subjects who underwent arthroplasty revision or resection surgery between March 2016 and October 2017 at Mayo Clinic in Rochester, Minnesota. Using the Infectious Diseases Society of America (IDSA) PJI diagnostic criteria (omitting culture criteria) as the gold standard, the sensitivity of tissue culture was similar to that of the sonicate fluid culture (66.4% versus 73.1%, P = 0.07) but was significantly lower than that of the two tests combined (66.4% versus 76.9%, P < 0.001). Using Bayesian latent class modeling, which assumes no gold standard for PJI diagnosis, the sensitivity of tissue culture was slightly lower than that of sonicate fluid culture (86.3% versus 88.7%) and much lower than that of the two tests combined (86.3% versus 99.1%). In conclusion, tissue culture in BCBs reached sensitivity similar to that of prosthesis sonicate fluid culture for diagnosis of PJI, but the two tests combined had the highest sensitivity without compromising specificity. The combination of tissue culture in BCBs and sonicate fluid culture is recommended to achieve the highest level of microbiological diagnosis of PJI.
Assuntos
Técnicas Bacteriológicas/instrumentação , Técnicas Bacteriológicas/métodos , Infecções Relacionadas à Prótese/diagnóstico , Manejo de Espécimes/métodos , Técnicas de Cultura de Tecidos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Contagem de Colônia Microbiana , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções Relacionadas à Prótese/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sonicação , Manejo de Espécimes/instrumentação , Infecções Estafilocócicas/diagnóstico , Staphylococcus/crescimento & desenvolvimento , Staphylococcus/isolamento & purificação , Técnicas de Cultura de Tecidos/instrumentaçãoRESUMO
Adaptive remodeling processes are essential to the maintenance and viability of coronary artery bypass grafts where clinical outcomes depend strongly on the tissue source. In this investigation, we utilized an ex vivo perfusion bioreactor to culture porcine analogs of common human bypass grafts: the internal thoracic artery (ITA), the radial artery (RA), and the great saphenous vein (GSV), and then evaluated samples acutely (6 h) and chronically (7 days) under in situ or coronary-like perfusion conditions. Although morphologically similar, primary cells harvested from the ITA illustrated lower intimal and medial, but not adventitial, cell proliferation rates than those from the RA or GSV. Basal gene expression levels were similar in all vessels, with only COL3A1, SERPINE1, FN1, and TGFB1 being differentially expressed prior to culture; however, over half of all genes were affected nominally by the culturing process. When exposed to coronary-like conditions, RAs and GSVs experienced pathological remodeling not present in ITAs or when vessels were studied in situ. Many of the remodeling genes perturbed at 6 h were restored after 7 days (COL3A1, FN1, MMP2, and TIMP1) while others (SERPINE1, TGFB1, and VCAM1) were not. The findings elucidate the potential mechanisms of graft failure and highlight strategies to encourage healthy ex vivo pregraft conditioning.
Assuntos
Artéria Torácica Interna/patologia , Perfusão , Artéria Radial/patologia , Veia Safena/patologia , Técnicas de Cultura de Tecidos , Remodelação Vascular , Animais , Reatores Biológicos , Proliferação de Células , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Artéria Torácica Interna/metabolismo , Perfusão/instrumentação , Artéria Radial/metabolismo , Veia Safena/metabolismo , Transdução de Sinais , Sus scrofa , Fatores de Tempo , Técnicas de Cultura de Tecidos/instrumentação , Remodelação Vascular/genéticaRESUMO
PURPOSE: Cell migration/invasion assays are widely used in commercial drug discovery screening. 3D printing enables the creation of diverse geometric restrictive barrier designs for use in cell motility studies, permitting on-demand assays. Here, the utility of 3D printed cell exclusion spacers (CES) was validated as a cell motility assay. METHODS: A novel CES fit was fabricated using 3D printing and customized to the size and contour of 12 cell culture plates including 6 well plates of basal human brain vascular endothelial (D3) cell migration cells compared with 6 well plates with D3 cells challenged with 1uM cytochalasin D (Cyto-D), an F-actin anti-motility drug. Control and Cyto-D treated cells were monitored over 3 days under optical microscopy. RESULTS: Day 3 cell migration distance for untreated D3 cells was 1515.943µm ± 10.346µm compared to 356.909µm ± 38.562µm for the Cyt-D treated D3 cells (p < 0.0001). By day 3, untreated D3 cells reached confluency and completely filled the original voided spacer regions, while the Cyt-D treated D3 cells remained significantly less motile. CONCLUSIONS: Cell migration distances were significantly reduced by Cyto-D, supporting the use of 3D printing for cell exclusion assays. 3D printed CES have great potential for studying cell motility, migration/invasion, and complex multi-cell interactions.
Assuntos
Técnicas de Cultura de Células/instrumentação , Ensaios de Migração Celular/instrumentação , Células Endoteliais/citologia , Impressão Tridimensional , Encéfalo/citologia , Linhagem Celular , Movimento Celular , Desenho de Equipamento , Humanos , Técnicas de Cultura de Tecidos/instrumentaçãoRESUMO
Recent breakthroughs in organ-on-a-chip and related technologies have highlighted the extraordinary potential for microfluidics to not only make lasting impacts in the understanding of biological systems but also to create new and important in vitro culture platforms. Adipose tissue (fat), in particular, is one that should be amenable to microfluidic mimics of its microenvironment. While the tissue was traditionally considered important only for energy storage, it is now understood to be an integral part of the endocrine system that secretes hormones and responds to various stimuli. As such, adipocyte function is central to the understanding of pathological conditions such as obesity, diabetes, and metabolic syndrome. Despite the importance of the tissue, only recently have significant strides been made in studying dynamic function of adipocytes or adipose tissues on microfluidic devices. In this critical review, we highlight new developments in the special class of microfluidic systems aimed at culture and interrogation of adipose tissue, a sub-field of microfluidics that we contend is only in its infancy. We close by reflecting on these studies as we forecast a promising future, where microfluidic technologies should be capable of mimicking the adipose tissue microenvironment and provide novel insights into its physiological roles in the normal and diseased states. Graphical abstract This critical review focuses on recent developments and challenges in applying microfluidic systems to the culture and analysis of adipocytes and adipose tissue.
Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Técnicas Analíticas Microfluídicas/métodos , Adipócitos/citologia , Adipocinas/metabolismo , Tecido Adiposo/citologia , Animais , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Desenho de Equipamento , Ácidos Graxos/metabolismo , Glucose/metabolismo , Hormônios/metabolismo , Humanos , Insulina/metabolismo , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodosRESUMO
DNA polymeric films (DNA-PFs) are a promising drug delivery system (DDS) in modern medicine. In this study, we evaluated the growth behavior of oral squamous cell carcinoma (OSCC) cells on DNA-PFs. The morphological, biochemical, and cytometric features of OSCC cell adhesion on DNA-PFs were also assessed. An initial, temporary alteration in cell morphology was observed at early time points owing to the inhibition of cell attachment to the film, which then returned to a normal morphological state at later time points. MTT and resazurin assays showed a moderate reduction in cell viability related to increased DNA concentration in the DNA-PFs. Flow cytometry studies showed low cytotoxicity of DNA-PFs, with cell viabilities higher than 90% in all the DNA-PFs tested. Flow cytometric cell cycle analysis also showed average cell cycle phase distributions at later time points, indicating that OSCC cell growth is maintained in the presence of DNA-PFs. These results show high biocompatibility of DNA-PFs and suggest their use in designing "dressing material," where the DNA film acts as a support for cell growth, or with incorporation of active or photoactive compounds, which can induce tissue regeneration and are useful to treat many diseases, especially oral cancer.
Assuntos
Proliferação de Células , DNA/química , Membranas Artificiais , Polímeros/química , Medicina Regenerativa , Técnicas de Cultura de Tecidos/instrumentação , Alicerces Teciduais/química , Materiais Biocompatíveis/análise , Materiais Biocompatíveis/farmacologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , DNA/farmacologia , Humanos , Teste de Materiais , Neoplasias Bucais/patologia , Polímeros/farmacologia , Medicina Regenerativa/instrumentação , Medicina Regenerativa/métodos , Técnicas de Cultura de Tecidos/métodosRESUMO
The purpose of this study was to assess and evaluate new bone formation in rabbit marginal mandibular defects using expanded bone marrow-derived osteoprogenitor cells seeded in three-dimensional scaffolds of polycaprolactone/tricalcium phosphate (PCL/TCP). Bone marrow was harvested from the rabbit ilium and rabbit bone marrow-derived osteoprogenitor cells were isolated and expanded in standard culture medium and osteogenic medium supplement. The cells were then seeded into the PCL/TCP scaffolds and the cell/scaffold constructions were implanted into prepared defects in rabbit mandibles. PCL/TCP scaffold alone and autogenous bone graft from the mandible were also implanted into the other prepared defects. The specimens were evaluated at 4 and 8 weeks after the implantation using clinical, radiographic, and histological techniques. The results of the experimental group demonstrated more newly formed bone on the surface and in the pores of the PCL/TCP scaffolds. In addition, the osteoblasts, osteocytes, and new bone trabeculae were identified throughout the defects that were implanted with the cell/scaffold constructions. The PCL/TCP alone group was filled mostly with fibrous cells particularly in the middle region with less bone formation. These results would suggest that the derived osteotoprogenitor cells have the potential to form bone tissue when seeded onto PCL/TCP scaffolds.
Assuntos
Células da Medula Óssea/citologia , Regeneração Óssea/fisiologia , Fosfatos de Cálcio/química , Doenças Mandibulares/terapia , Poliésteres/química , Células-Tronco/citologia , Alicerces Teciduais/química , Animais , Células da Medula Óssea/fisiologia , Proliferação de Células , Masculino , Mandíbula/patologia , Doenças Mandibulares/patologia , Teste de Materiais , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese/fisiologia , Coelhos , Células-Tronco/fisiologia , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodosRESUMO
We propose an in vitro method for studying permeability of spinal cord dura mater for components of autological serum using an original device. Sixty native samples of the spinal cord dura mater obtained from 12 mongrel dogs were used for testing of the device. The coefficient of permeability variation (V) for blood serum substances did not exceed 5% in most cases excluding lactate (V=8.03%). Analysis of spinal cord dura mater permeability in vitro for various substances using the developed device provides reproducible results with acceptable variability (5-10%).
Assuntos
Cultura em Câmaras de Difusão/veterinária , Dura-Máter/metabolismo , Medula Espinal/metabolismo , Técnicas de Cultura de Tecidos/instrumentação , Animais , Cálcio/metabolismo , Colesterol/metabolismo , Creatinina/metabolismo , Difusão , Cães , Feminino , Glucose/metabolismo , Cinética , Ácido Láctico/metabolismo , Masculino , Permeabilidade , Fosfatos/metabolismo , Albumina Sérica/metabolismo , Triglicerídeos/metabolismo , Ureia/metabolismoRESUMO
Key developmental processes that occur on the subcellular and cellular level or occur in occluded tissues are difficult to access, let alone image and analyze. Recently, culturing living samples within polydimethylsiloxane (PDMS) microfluidic devices has facilitated the study of hard-to-reach developmental events. Here, we show that an early diverging land plant, Physcomitrella patens, can be continuously cultured within PDMS microfluidic chambers. Because the PDMS chambers are bonded to a coverslip, it is possible to image P. patens development at high resolution over long time periods. Using PDMS chambers, we report that wild-type protonemal tissue grows at the same rate as previously reported for growth on solid medium. Using long-term imaging, we highlight key developmental events, demonstrate compatibility with high-resolution confocal microscopy, and obtain growth rates for a slow-growing mutant. By coupling the powerful genetic tools available to P. patens with long-term growth and imaging provided by PDMS microfluidic chambers, we demonstrate the capability to study cellular and subcellular developmental events in plants directly and in real time.
Assuntos
Bryopsida/crescimento & desenvolvimento , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/métodos , Bryopsida/citologia , Bryopsida/genética , Dimetilpolisiloxanos/química , Microscopia Confocal , Mutação , Reprodutibilidade dos Testes , Fatores de Tempo , Imagem com Lapso de Tempo/métodos , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodosRESUMO
In nature, helical macromolecules such as collagen, chitin and cellulose are critical to the morphogenesis and functionality of various hierarchically structured materials. During tissue formation, these chiral macromolecules are secreted and undergo self-templating assembly, a process whereby multiple kinetic factors influence the assembly of the incoming building blocks to produce non-equilibrium structures. A single macromolecule can form diverse functional structures when self-templated under different conditions. Collagen type I, for instance, forms transparent corneal tissues from orthogonally aligned nematic fibres, distinctively coloured skin tissues from cholesteric phase fibre bundles, and mineralized tissues from hierarchically organized fibres. Nature's self-templated materials surpass the functional and structural complexity achievable by current top-down and bottom-up fabrication methods. However, self-templating has not been thoroughly explored for engineering synthetic materials. Here we demonstrate the biomimetic, self-templating assembly of chiral colloidal particles (M13 phage) into functional materials. A single-step process produces long-range-ordered, supramolecular films showing multiple levels of hierarchical organization and helical twist. Three distinct supramolecular structures are created by this approach: nematic orthogonal twists, cholesteric helical ribbons and smectic helicolidal nanofilaments. Both chiral liquid crystalline phase transitions and competing interfacial forces at the interface are found to be critical factors in determining the morphology of the templated structures during assembly. The resulting materials show distinctive optical and photonic properties, functioning as chiral reflector/filters and structural colour matrices. In addition, M13 phages with genetically incorporated bioactive peptide ligands direct both soft and hard tissue growth in a hierarchically organized manner. Our assembly approach provides insight into the complexities of hierarchical assembly in nature and could be expanded to other chiral molecules to engineer sophisticated functional helical-twisted structures.
Assuntos
Bacteriófago M13/fisiologia , Materiais Biomiméticos/química , Animais , Bacteriófago M13/química , Materiais Biomiméticos/síntese química , Linhagem Celular , Substâncias Macromoleculares/química , Camundongos , Rotação Ocular , Técnicas de Cultura de Tecidos/instrumentação , Vírion/químicaRESUMO
Gonads of sea urchin are consumed in Japan and some countries as food and most parts including its tests are discarded as marine wastes. Therefore, utilization of them as functional materials would reduce the waste as well as encourage Japanese fishery. In this study, magnesium containing calcite granules collected from sea urchin tests were hydrothermally phosphatized and the obtained granules were identified as approximately 82% in mass of magnesium containing ß-tricalcium phosphate and 18% in mass of nonstoichiometric hydroxyapatite, i.e., a biphasic calcium phosphate, maintaining the original porous network. Shape-controlled scaffolds were fabricated with the obtained biphasic calcium phosphate granules and collagen. The scaffolds showed good open porosity (83.84%) and adequate mechanical properties for handling during cell culture and subsequent operations. The MG-63 cells showed higher proliferation and osteogenic differentiation in comparison to a control material, the collagen sponge with the same size. Furthermore, cell viability assay proved that the scaffolds were not cytotoxic. These results suggest that scaffold prepared using sea urchin test derived calcium phosphate and collagen could be a potential candidate of bone void fillers for non-load bearing defects in bone reconstruction as well as scaffolds for bone tissue engineering.