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1.
J Cell Sci ; 135(24)2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36546396

RESUMEN

Pancreatic cancer is a deadly and highly metastatic disease, although how metastatic lesions establish is not fully understood. A key feature of pancreatic tumours is extensive fibrosis and deposition of extracellular matrix (ECM). While pancreatic cancer cells are programmed by stimuli derived from a stiff ECM, metastasis requires loss of attachment and adaptation to a softer microenvironment at distant sites. Growing evidence suggests that stiff ECM influences pancreatic cancer cell behaviour. Here, we argue that this influence is reversible and that pancreatic cancer cells can be reprogrammed upon sensing soft substrates. Using engineered polyacrylamide hydrogels with tuneable mechanical properties, we show that collagen VI is specifically upregulated in pancreatic cancer cells on soft substrates, due to a lack of integrin engagement. Furthermore, the expression of collagen VI is inversely correlated with mechanosensing and activity of YAP (also known as YAP1), which might be due to a direct or indirect effect on transcription of genes encoding collagen VI. Collagen VI supports migration in vitro and metastasis formation in vivo. Metastatic nodules formed by pancreatic cancer cells lacking Col6a1 display stromal cell-derived collagen VI deposition, suggesting that collagen VI derived from either cancer cells or the stroma is an essential component of the metastatic niche. This article has an associated First Person interview with Vasileios Papalazarou, joint first author of the paper.


Asunto(s)
Colágeno , Neoplasias Pancreáticas , Humanos , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Integrinas/metabolismo , Microambiente Tumoral , Neoplasias Pancreáticas
2.
Development ; 147(22)2020 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-33028610

RESUMEN

The Arp2/3 complex is essential for the assembly of branched filamentous actin, but its role in physiology and development is surprisingly little understood. Melanoblasts deriving from the neural crest migrate along the developing embryo and traverse the dermis to reach the epidermis, colonising the skin and eventually homing within the hair follicles. We have previously established that Rac1 and Cdc42 direct melanoblast migration in vivo We hypothesised that the Arp2/3 complex might be the main downstream effector of these small GTPases. Arp3 depletion in the melanocyte lineage results in severe pigmentation defects in dorsal and ventral regions of the mouse skin. Arp3 null melanoblasts demonstrate proliferation and migration defects and fail to elongate as their wild-type counterparts. Conditional deletion of Arp3 in primary melanocytes causes improper proliferation, spreading, migration and adhesion to extracellular matrix. Collectively, our results suggest that the Arp2/3 complex is absolutely indispensable in the melanocyte lineage in mouse development, and indicate a significant role in developmental processes that require tight regulation of actin-mediated motility.


Asunto(s)
Complejo 2-3 Proteico Relacionado con la Actina/metabolismo , Adhesión Celular , Proliferación Celular , Melanocitos/metabolismo , Pigmentación de la Piel , Piel/metabolismo , Complejo 2-3 Proteico Relacionado con la Actina/genética , Animales , Línea Celular , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Melanocitos/citología , Ratones , Neuropéptidos/genética , Neuropéptidos/metabolismo , Piel/citología , Proteína de Unión al GTP cdc42/genética , Proteína de Unión al GTP cdc42/metabolismo , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo
3.
Circ Res ; 126(8): 988-1003, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32065054

RESUMEN

RATIONALE: Despite increasing understanding of the prognostic importance of vascular stiffening linked to perivascular fibrosis in hypertension, the molecular and cellular regulation of this process is poorly understood. OBJECTIVES: To study the functional role of microRNA-214 (miR-214) in the induction of perivascular fibrosis and endothelial dysfunction driving vascular stiffening. METHODS AND RESULTS: Out of 381 miRs screened in the perivascular tissues in response to Ang II (angiotensin II)-mediated hypertension, miR-214 showed the highest induction (8-fold, P=0.0001). MiR-214 induction was pronounced in perivascular and circulating T cells, but not in perivascular adipose tissue adipocytes. Global deletion of miR-214-/- prevented Ang II-induced periaortic fibrosis, Col1a1, Col3a1, Col5a1, and Tgfb1 expression, hydroxyproline accumulation, and vascular stiffening, without difference in blood pressure. Mechanistic studies revealed that miR-214-/- mice were protected against endothelial dysfunction, oxidative stress, and increased Nox2, all of which were induced by Ang II in WT mice. Ang II-induced recruitment of T cells into perivascular adipose tissue was abolished in miR-214-/- mice. Adoptive transfer of miR-214-/- T cells into RAG1-/- mice resulted in reduced perivascular fibrosis compared with the effect of WT T cells. Ang II induced hypertension caused significant change in the expression of 1380 T cell genes in WT, but only 51 in miR-214-/-. T cell activation, proliferation and chemotaxis pathways were differentially affected. MiR-214-/- prevented Ang II-induction of profibrotic T cell cytokines (IL-17, TNF-α, IL-9, and IFN-γ) and chemokine receptors (CCR1, CCR2, CCR4, CCR5, CCR6, and CXCR3). This manifested in reduced in vitro and in vivo T cell chemotaxis resulting in attenuation of profibrotic perivascular inflammation. Translationally, we show that miR-214 is increased in plasma of patients with hypertension and is directly correlated to pulse wave velocity as a measure of vascular stiffness. CONCLUSIONS: T-cell-derived miR-214 controls pathological perivascular fibrosis in hypertension mediated by T cell recruitment and local profibrotic cytokine release.


Asunto(s)
Endotelio Vascular/metabolismo , Hipertensión/genética , Hipertensión/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Linfocitos T/metabolismo , Animales , Endotelio Vascular/patología , Fibrosis/genética , Fibrosis/metabolismo , Fibrosis/patología , Humanos , Hipertensión/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Análisis de la Onda del Pulso/métodos , Linfocitos T/patología , Transcriptoma/fisiología
4.
EMBO J ; 36(16): 2373-2389, 2017 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-28694244

RESUMEN

Tumor progression alters the composition and physical properties of the extracellular matrix. Particularly, increased matrix stiffness has profound effects on tumor growth and metastasis. While endothelial cells are key players in cancer progression, the influence of tumor stiffness on the endothelium and the impact on metastasis is unknown. Through quantitative mass spectrometry, we find that the matricellular protein CCN1/CYR61 is highly regulated by stiffness in endothelial cells. We show that stiffness-induced CCN1 activates ß-catenin nuclear translocation and signaling and that this contributes to upregulate N-cadherin levels on the surface of the endothelium, in vitro This facilitates N-cadherin-dependent cancer cell-endothelium interaction. Using intravital imaging, we show that knockout of Ccn1 in endothelial cells inhibits melanoma cancer cell binding to the blood vessels, a critical step in cancer cell transit through the vasculature to metastasize. Targeting stiffness-induced changes in the vasculature, such as CCN1, is therefore a potential yet unappreciated mechanism to impair metastasis.


Asunto(s)
Comunicación Celular , Células Endoteliales/fisiología , Melanocitos/fisiología , Cadherinas/análisis , Línea Celular , Proteína 61 Rica en Cisteína/análisis , Regulación de la Expresión Génica , Humanos , Espectrometría de Masas , beta Catenina/análisis
5.
Cell Biol Toxicol ; 37(6): 915-933, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33420657

RESUMEN

Mesenchymal stem cells represent an important resource, for bone regenerative medicine and therapeutic applications. This review focuses on new advancements and biophysical tools which exploit different physical and chemical markers of mesenchymal stem cell populations, to finely characterize phenotype changes along their osteogenic differentiation process. Special attention is paid to recently developed label-free methods, which allow monitoring cell populations with minimal invasiveness. Among them, quantitative phase imaging, suitable for single-cell morphometric analysis, and nanoindentation, functional to cellular biomechanics investigation. Moreover, the pool of ion channels expressed in cells during differentiation is discussed, with particular interest for calcium homoeostasis.Altogether, a biophysical perspective of osteogenesis is proposed, offering a valuable tool for the assessment of the cell stage, but also suggesting potential physiological links between apparently independent phenomena.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Biomarcadores , Diferenciación Celular , Células Cultivadas
6.
Biochem J ; 477(17): 3349-3366, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32941644

RESUMEN

Twenty-five years have passed since the first clinical trial utilising mesenchymal stomal/stem cells (MSCs) in 1995. In this time academic research has grown our understanding of MSC biochemistry and our ability to manipulate these cells in vitro using chemical, biomaterial, and mechanical methods. Research has been emboldened by the promise that MSCs can treat illness and repair damaged tissues through their capacity for immunomodulation and differentiation. Since 1995, 31 therapeutic products containing MSCs and/or progenitors have reached the market with the level of in vitro manipulation varying significantly. In this review, we summarise existing therapeutic products containing MSCs or mesenchymal progenitor cells and examine the challenges faced when developing new therapeutic products. Successful progression to clinical trial, and ultimately market, requires a thorough understanding of these hurdles at the earliest stages of in vitro pre-clinical development. It is beneficial to understand the health economic benefit for a new product and the reimbursement potential within various healthcare systems. Pre-clinical studies should be selected to demonstrate efficacy and safety for the specific clinical indication in humans, to avoid duplication of effort and minimise animal usage. Early consideration should also be given to manufacturing: how cell manipulation methods will integrate into highly controlled workflows and how they will be scaled up to produce clinically relevant quantities of cells. Finally, we summarise the main regulatory pathways for these clinical products, which can help shape early therapeutic design and testing.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Factores Inmunológicos , Inmunomodulación , Células Madre Mesenquimatosas/metabolismo , Animales , Humanos , Factores Inmunológicos/metabolismo , Factores Inmunológicos/uso terapéutico
7.
Proc Natl Acad Sci U S A ; 115(6): 1192-1197, 2018 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-29358406

RESUMEN

Cell response to matrix rigidity has been explained by the mechanical properties of the actin-talin-integrin-fibronectin clutch. Here the molecular clutch model is extended to account for cell interactions with purely viscous surfaces (i.e., without an elastic component). Supported lipid bilayers present an idealized and controllable system through which to study this concept. Using lipids of different diffusion coefficients, the mobility (i.e., surface viscosity) of the presented ligands (in this case RGD) was altered by an order of magnitude. Cell size and cytoskeletal organization were proportional to viscosity. Furthermore, there was a higher number of focal adhesions and a higher phosphorylation of FAK on less-mobile (more-viscous) surfaces. Actin retrograde flow, an indicator of the force exerted on surfaces, was also seen to be faster on more mobile surfaces. This has consequential effects on downstream molecules; the mechanosensitive YAP protein localized to the nucleus more on less-mobile (more-viscous) surfaces and differentiation of myoblast cells was enhanced on higher viscosity. This behavior was explained within the framework of the molecular clutch model, with lower viscosity leading to a low force loading rate, preventing the exposure of mechanosensitive proteins, and with a higher viscosity causing a higher force loading rate exposing these sites, activating downstream pathways. Consequently, the understanding of how viscosity (regardless of matrix stiffness) influences cell response adds a further tool to engineer materials that control cell behavior.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Quinasa 1 de Adhesión Focal/metabolismo , Membrana Dobles de Lípidos/química , Mioblastos/citología , Fosfoproteínas/metabolismo , Actinas/metabolismo , Animales , Proteínas de Ciclo Celular , Línea Celular , Forma de la Célula , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fibronectinas/química , Adhesiones Focales , Membrana Dobles de Lípidos/metabolismo , Ratones , Microscopía de Fuerza Atómica , Mioblastos/metabolismo , Oligopéptidos/química , Oligopéptidos/metabolismo , Fosfatidilcolinas/química , Propiedades de Superficie , Viscosidad , Proteínas Señalizadoras YAP
8.
Small ; 16(31): e2001975, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32603002

RESUMEN

Grooved topography and inherent cell contact guidance has shown promising results regarding cell proliferation, morphology, and lineage-specific differentiation. Yet these approaches are limited to 2D applications. Sandwich-culture conditions are developed to bridge the gap between 2D and 3D culture, enabling both ventral and dorsal cell surface stimulation. The effect of grooved surface topography is accessed on cell orientation and elongation in a highly controlled manner, with simultaneous and independent stimuli on two cell sides. Nanogrooved and non-nanogrooved substrates are assembled into quasi-3D systems with variable relative orientations. A plethora of sandwich-culture conditions are created by seeding cells on lower, upper, or both substrates. Software image analysis demonstrates that F-actin of cells acquires the orientation of the substrate on which cells are initially seeded, independently from the orientation of the second top substrate. Contrasting cell morphologies are observed, with a higher elongation for nanogrooved 2D substrates than nanogrooved sandwich-culture conditions. Correlated with an increased pFAK activity and vinculin staining for sandwich-culture conditions, these results point to an enhanced cell surface stimulation versus control conditions. The pivotal role of initial cell-biomaterial contact on cellular alignment is highlighted, providing important insights for tissue engineering strategies aiming to guide cellular response through mechanotransduction approaches.


Asunto(s)
Mecanotransducción Celular , Ingeniería de Tejidos , Diferenciación Celular , Proliferación Celular , Propiedades de Superficie
9.
Philos Trans A Math Phys Eng Sci ; 376(2120)2018 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-29661978

RESUMEN

Mechanical signals are ubiquitous in our everyday life and the process of converting these mechanical signals into a biological signalling response is known as mechanotransduction. Our understanding of mechanotransduction, and its contribution to vital cellular responses, is a rapidly expanding field of research involving complex processes that are still not clearly understood. The use of mechanical vibration as a stimulus of mechanotransduction, including variation of frequency and amplitude, allows an alternative method to control specific cell behaviour without chemical stimulation (e.g. growth factors). Chemical-independent control of cell behaviour could be highly advantageous for fields including drug discovery and clinical tissue engineering. In this review, a novel technique is described based on nanoscale sinusoidal vibration. Using finite-element analysis in conjunction with laser interferometry, techniques that are used within the field of gravitational wave detection, optimization of apparatus design and calibration of vibration application have been performed. We further discuss the application of nanovibrational stimulation, or 'nanokicking', to eukaryotic and prokaryotic cells including the differentiation of mesenchymal stem cells towards an osteoblast cell lineage. Mechanotransductive mechanisms are discussed including mediation through the Rho-A kinase signalling pathway. Optimization of this technique was first performed in two-dimensional culture using a simple vibration platform with an optimal frequency and amplitude of 1 kHz and 22 nm. A novel bioreactor was developed to scale up cell production, with recent research demonstrating that mesenchymal stem cell differentiation can be efficiently triggered in soft gel constructs. This important step provides first evidence that clinically relevant (three-dimensional) volumes of osteoblasts can be produced for the purpose of bone grafting, without complex scaffolds and/or chemical induction. Initial findings have shown that nanovibrational stimulation can also reduce biofilm formation in a number of clinically relevant bacteria. This demonstrates additional utility of the bioreactor to investigate mechanotransduction in other fields of research.This article is part of a discussion meeting issue 'The promises of gravitational-wave astronomy'.

10.
Nanomedicine ; 14(7): 2455-2464, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28552647

RESUMEN

Regulation of cell behavior in response to nanoscale features has been the focus of much research in recent years and the successful generation of nanoscale features capable of mimicking the natural nanoscale interface has been of great interest in the field of biomaterials research. In this review, we discuss relevant nanofabrication techniques and how they are combined with bioengineering applications to mimic the natural extracellular matrix (ECM) and create valuable nanoscale interfaces.


Asunto(s)
Materiales Biocompatibles/química , Biomimética , Adhesión Celular , Matriz Extracelular/química , Nanoestructuras/química , Animales , Humanos
11.
Langmuir ; 32(3): 800-9, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26715432

RESUMEN

Cells, by interacting with surfaces indirectly through a layer of extracellular matrix proteins, can respond to a variety of physical properties, such as topography or stiffness. Polymer surface mobility is another physical property that is less well understood but has been indicated to hold the potential to modulate cell behavior. Polymer mobility is related to the glass-transition temperature (Tg) of the system, the point at which a polymer transitions from an amorphous solid to a more liquid-like state. This work shows that changes in polymer mobility translate to interfacial mobility of extracellular matrix proteins adsorbed on the material surface. This study has utilized a family of polyalkyl acrylates with similar chemistry but different degrees of mobility, obtained through increasing length of the side chain. These materials are used, in conjunction with fluorescent fibronectin, to determine the mobility of this interfacial layer of protein that constitutes the initial cell-material interface. Furthermore, the extent of fibronectin domain availability (III9, III10, - the integrin binding site), cell-mediated reorganization, and cell differentiation was also determined. A nonmonotonic dependence of fibronectin mobility on polymer surface mobility was observed, with a similar trend noted in cell-mediated reorganization of the protein layer by L929 fibroblasts. The availability of the integrin-binding site was higher on the more mobile surfaces, where a similar organization of the protein into networks at the material interface was observed. Finally, differentiation of C2C12 myoblasts was seen to be highly sensitive to surface mobility upon inhibition of cell contractility. Altogether, these findings show that polymer mobility is a subtle influence that translates to the cell/material interface through the protein layer to alter the biological activity of the surface.


Asunto(s)
Acrilatos/química , Proteínas de la Matriz Extracelular/química , Fibronectinas/química , Integrinas/química , Animales , Adhesión Celular , Línea Celular , Fibroblastos/química , Fibroblastos/citología , Fluoresceína-5-Isotiocianato/química , Colorantes Fluorescentes/química , Ratones , Mioblastos/química , Mioblastos/citología , Transición de Fase , Unión Proteica , Transporte de Proteínas , Propiedades de Superficie , Temperatura de Transición
12.
Adv Mater ; 36(23): e2310789, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38253339

RESUMEN

Conventional osteogenic platforms utilize active growth factors to repair bone defects that are extensive in size, but they can adversely affect patient health. Here, an unconventional osteogenic platform is reported that functions by promoting capture of inactive osteogenic growth factor molecules to the site of cell growth for subsequent integrin-mediated activation, using a recombinant fragment of latent transforming growth factor beta-binding protein-1 (rLTBP1). It is shown that rLTBP1 binds to the growth-factor- and integrin-binding domains of fibronectin on poly(ethyl acrylate) surfaces, which immobilizes rLTBP1 and promotes the binding of latency associated peptide (LAP), within which inactive transforming growth factor beta 1 (TGF-ß1) is bound. rLTBP1 facilitates the interaction of LAP with integrin ß1 and the subsequent mechanically driven release of TGF-ß1 to stimulate canonical TGF-ß1 signaling, activating osteogenic marker expression in vitro and complete regeneration of a critical-sized bone defect in vivo.


Asunto(s)
Osteogénesis , Factor de Crecimiento Transformador beta1 , Animales , Humanos , Factor de Crecimiento Transformador beta1/metabolismo , Fibronectinas/metabolismo , Fibronectinas/química , Proteínas de Unión a TGF-beta Latente/metabolismo , Proteínas de Unión a TGF-beta Latente/química , Regeneración Ósea , Propiedades de Superficie , Integrinas/metabolismo , Unión Proteica , Integrina beta1/metabolismo , Transducción de Señal
13.
ACS Appl Mater Interfaces ; 16(26): 32930-32944, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38888932

RESUMEN

Protein materials are versatile tools in diverse biomedical fields. Among them, artificial secretory granules (SGs), mimicking those from the endocrine system, act as mechanically stable reservoirs for the sustained release of proteins as oligomeric functional nanoparticles. Only validated in oncology, the physicochemical properties of SGs, along with their combined drug-releasing and scaffolding abilities, make them suitable as smart topographies in regenerative medicine for the prolonged delivery of growth factors (GFs). Thus, considering the need for novel, safe, and cost-effective materials to present GFs, in this study, we aimed to biofabricate a protein platform combining both endocrine-like and extracellular matrix fibronectin-derived (ECM-FN) systems. This approach is based on the sustained delivery of a nanostructured histidine-tagged version of human fibroblast growth factor 2. The GF is presented onto polymeric surfaces, interacting with FN to spontaneously generate nanonetworks that absorb and present the GF in the solid state, to modulate mesenchymal stromal cell (MSC) behavior. The results show that SGs-based topographies trigger high rates of MSCs proliferation while preventing differentiation. While this could be useful in cell therapy manufacture demanding large numbers of unspecialized MSCs, it fully validates the hybrid platform as a convenient setup for the design of biologically active hybrid surfaces and in tissue engineering for the controlled manipulation of mammalian cell growth.


Asunto(s)
Matriz Extracelular , Fibronectinas , Células Madre Mesenquimatosas , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fibronectinas/química , Factor 2 de Crecimiento de Fibroblastos/química , Factor 2 de Crecimiento de Fibroblastos/farmacología , Proliferación Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Nanoestructuras/química
14.
Biotechnol Bioeng ; 110(11): 3048-58, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23744752

RESUMEN

While most of the in vivo extracellular matrices are 3D, most of the in vitro cultures are 2D--where only ventral adhesion is permitted--thus modifying cell behavior as a way to self-adaptation to this unnatural environment. We hypothesize that the excitation of dorsal receptors in cells already attached on a 2D surface (sandwich culture) could cover the gap between 2D and 3D cell-material interactions and result in a more physiological cell behavior. In this study we investigate the role of dorsal stimulation on myoblast differentiation within different poly(L-lactic acid) (PLLA) sandwich-like microenvironments, including plain material and aligned fibers. Enhanced cell differentiation levels were found for cells cultured with dorsal fibronectin-coated films. Seeking to understand the underlying mechanisms, experiments were carried out with (i) different types of dorsal stimuli (FN, albumin, FN after blocking the RGD integrin-binding site and activating dorsal cell integrin receptors), (ii) in the presence of an inhibitor of cell contractility, and (iii) increasing the frequency of culture medium changes to assess the effect of paracrine factors. Furthermore, FAK and integrin expressions, determined by Western blotting, revealed differences between cell sandwiches and 2D controls. Results show a stimuli-dependent response to dorsal excitation, proving that integrin outside-in signaling is involved in the enhanced cell differentiation. Due to their easiness and versatility, these sandwich-like systems are excellent candidates to get deeper insights into the study of 3D cell behavior and to direct cell fate within multilayer constructs.


Asunto(s)
Diferenciación Celular , Mioblastos/fisiología , Transducción de Señal , Animales , Técnicas de Cultivo de Célula/métodos , Línea Celular , Medios de Cultivo/química , Ratones
15.
Med Oral Patol Oral Cir Bucal ; 18(4): e733-6, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23524430

RESUMEN

OBJECTIVE: To study nanostructural dentinal changes produced by endodontic irrigants. STUDY DESIGN: Experimental study. Nanoindentations were performed on peritubular (PD) and intertubular dentine (ID) with an atomic force microscopy. Stiffness and adhesion force were determined before and after application of 5.25% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA). Normalized differences before and after treatment for stiffness and adhesion forces were calculated. A paired T-test was used to compare stiffness and adhesion force before and after irrigants application. RESULTS: After treatment with EDTA there was a 29.80% reduction in stiffness in ID and a 63.53% reduction in PD. Adhesion force was reduced by 21.22% and 8.21% respectively. After treatment with 5.25% NaOCI stiffness was reduced by 2.49% in ID and increased by 15.01% in PD. Adhesion force increased by 25.11% and 23.97% respectively. CONCLUSIONS: 17% EDTA reduced stiffness and adhesion force in ID and PD. Treatment with NaOCI at 5.25% had no significant effect on stiffness but did affect adhesion force in ID and PD.


Asunto(s)
Dentina/efectos de los fármacos , Dentina/ultraestructura , Ácido Edético/farmacología , Irrigantes del Conducto Radicular/farmacología , Hipoclorito de Sodio/farmacología , Humanos , Técnicas In Vitro
16.
Adv Healthc Mater ; 12(17): e2202110, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36938891

RESUMEN

Tissue engineering aims at replicating tissues and organs to develop applications in vivo and in vitro. In vivo, by engineering artificial constructs using functional materials and cells to provide both physiological form and function. In vitro, by engineering three-dimensional (3D) models to support drug discovery and enable understanding of fundamental biology. 3D culture constructs mimic cell-cell and cell-matrix interactions and use biomaterials seeking to increase the resemblance of engineered tissues with its in vivo homologues. Native tissues, however, include complex architectures, with compartmentalized regions of different properties containing different types of cells that can be captured by multicompartment constructs. Recent advances in fabrication technologies, such as micropatterning, microfluidics or 3D bioprinting, have enabled compartmentalized structures with defined compositions and properties that are essential in creating 3D cell-laden multiphasic complex architectures. This review focuses on advances in engineered multicompartment constructs that mimic tissue heterogeneity. It includes multiphasic 3D implantable scaffolds and in vitro models, including systems that incorporate different regions emulating in vivo tissues, highlighting the emergence and relevance of 3D bioprinting in the future of biological research and medicine.


Asunto(s)
Bioimpresión , Impresión Tridimensional , Hidrogeles/química , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/química , Andamios del Tejido/química
17.
ACS Appl Bio Mater ; 6(5): 1755-1762, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37067245

RESUMEN

Fibronectin (FN) mediates cell-material interactions during events such as tissue repair, and therefore the biomimetic modeling of this protein in vitro benefits regeneration. The nature of the interface is crucial in determining cell adhesion, morphology, and differentiation. Poly(ethyl acrylate) (PEA) spontaneously organizes FN into biological nanonetworks, resulting in exceptional bone regeneration in animal models. Spontaneous network organization of FN is also observed in poly(buthyl acrylate) (PBA) substrates that have higher surface mobility than PEA. C2C12 myoblasts differentiate efficiently on PEA and PBA substrates. In this study, we investigate if intermediate surface mobilities between PEA and PBA induce cell differentiation more efficiently than PEA. A family of P(EA-co-BA) copolymers were synthesized in the entire range of compositions to finely tune surface mobility between PEA and PBA. Surface characterization demonstrates that FN mobility steadily increased with the PBA content. All compositions allowed the biological organization of FN with similar exposure of cell binding domains. C2C12 myoblasts adhered well in all the materials, with higher focal adhesions in PEA and PBA. The increase of the interfacial mobility had an impact in cell adhesion by increasing the number of FAs per cell. In addition, cell differentiation decreased proportionally with surface mobility, from PEA to PBA.


Asunto(s)
Acrilatos , Animales , Adhesión Celular , Diferenciación Celular , Acrilatos/farmacología
18.
Biomater Adv ; 154: 213587, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37633007

RESUMEN

In this work, Engineered Living Materials (ELMs), based on the combination of genetically-modified bacteria and mineral-reinforced organic matrices, and endowed with self-healing or regenerative properties and adaptation to specific biological environments were developed. Concretely, we produced ELMs combining human mesenchymal stem cells (hMSCs) and Lactococcus lactis (L. lactis), which was specifically programmed to deliver bone morphogenetic protein (BMP-2) upon external stimulation using nisin, into mineralized alginate matrices. The hybrid organic/inorganic matrix was built through a protocol, inspired by bone mineralization, in which alginate (Alg) assembly and apatite (HA) mineralization occurred simultaneously driven by calcium ions. Chemical composition, structure and reologhical properties of the hybrid 3D matrices were dedicately optimized prior the incorportation of the living entities. Then, the same protocol was reproduced in the presence of hMSC and engineered L. lactis that secrete BMP-2 resulting in 3D hybrid living hydrogels. hMSC viability and osteogenic differentiation in the absence and presence of the bacteria were evaluated by live/dead and quantitative real-time polymerase chain reaction (qPCR) and immunofluorescence assays, respectively. Results demonstrate that these 3D engineered living material support osteogenic differentiation of hMSCs due to the synergistic effect between HA and the growth factors BMP-2 delivered by L. lactis.


Asunto(s)
Calcinosis , Células Madre Mesenquimatosas , Humanos , Osteogénesis/genética , Andamios del Tejido/química , Células Madre Mesenquimatosas/metabolismo , Alginatos , Diferenciación Celular , Calcinosis/metabolismo
19.
Biomater Adv ; 153: 213576, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37566937

RESUMEN

Cell-based liver therapies based on retrieving and steadying failed metabolic function(s) for acute and chronic diseases could be a valuable substitute for liver transplants, even though they are limited by the low engraftment capability and reduced functional quality of primary human hepatocytes (PHH). In this paper we propose the use of gelatin-hyaluronic acid (Gel-HA) scaffolds seeded with PHH for the treatment of liver failure. We first optimized the composition using Gel-HA hydrogels, looking for the mechanical properties closer to the human liver and determining HepG2 cells functionality. Gel-HA scaffolds with interconnected porosity (pore size 102 µm) were prepared and used for PHH culture and evaluation of key hepatic functions. PHH cultured in Gel-HA scaffolds exhibited increased albumin and urea secretion and metabolic capacity (CYP and UGT activity levels) compared to standard monolayer cultures. The transplant of the scaffold containing PHH led to an improvement in liver function (transaminase levels, necrosis) and ameliorated damage in a mouse model of acetaminophen (APAP)-induced liver failure. The study provided a mechanistic understanding of APAP-induced liver injury and the impact of transplantation by analyzing cytokine production and oxidative stress induction to find suitable biomarkers of cell therapy effectiveness.


Asunto(s)
Acetaminofén , Fallo Hepático Agudo , Ratones , Animales , Humanos , Acetaminofén/toxicidad , Acetaminofén/metabolismo , Hepatocitos/metabolismo , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/terapia , Fallo Hepático Agudo/metabolismo , Células Hep G2 , Ácido Hialurónico/metabolismo
20.
Artículo en Inglés | MEDLINE | ID: mdl-37718477

RESUMEN

There is an unmet clinical need to provide viable bone grafts for clinical use. Autologous bone, one of the most commonly transplanted tissues, is often used but is associated with donor site morbidity. Tissue engineering strategies to differentiate an autologous cell source, such as mesenchymal stromal cells (MSCs), into a potential bone-graft material could help to fulfill clinical demand. However, osteogenesis of MSCs can typically require long culture periods that are impractical in a clinical setting and can lead to significant cost. Investigation into strategies that optimize cell production is essential. Here, we use the piezoelectric copolymer poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE), functionalized with a poly(ethyl acrylate) (PEA) coating that drives fibronectin network formation, to enhance MSC adhesion and to present growth factors in the solid phase. Dynamic electrical cues are then incorporated, via a nanovibrational bioreactor, and the MSC response to electromechanical stimulation is investigated.

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