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1.
Nat Commun ; 11(1): 5079, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033234

RESUMO

Tumor heterogeneity and lack of knowledge about resistant cell states remain a barrier to targeted cancer therapies. Basal cell carcinomas (BCCs) depend on Hedgehog (Hh)/Gli signaling, but can develop mechanisms of Smoothened (SMO) inhibitor resistance. We previously identified a nuclear myocardin-related transcription factor (nMRTF) resistance pathway that amplifies noncanonical Gli1 activity, but characteristics and drivers of the nMRTF cell state remain unknown. Here, we use single cell RNA-sequencing of patient tumors to identify three prognostic surface markers (LYPD3, TACSTD2, and LY6D) which correlate with nMRTF and resistance to SMO inhibitors. The nMRTF cell state resembles transit-amplifying cells of the hair follicle matrix, with AP-1 and TGFß cooperativity driving nMRTF activation. JNK/AP-1 signaling commissions chromatin accessibility and Smad3 DNA binding leading to a transcriptional program of RhoGEFs that facilitate nMRTF activity. Importantly, small molecule AP-1 inhibitors selectively target LYPD3+/TACSTD2+/LY6D+ nMRTF human BCCs ex vivo, opening an avenue for improving combinatorial therapies.


Assuntos
Carcinoma Basocelular/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Neoplasias Cutâneas/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/metabolismo , DNA de Neoplasias/metabolismo , Resistencia a Medicamentos Antineoplásicos , Matriz Extracelular/metabolismo , Ontologia Genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Folículo Piloso/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Proteína Smad3/metabolismo , Transativadores/metabolismo , Regulação para Cima
2.
Nat Commun ; 11(1): 4907, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999289

RESUMO

Global alterations in the metabolic network provide substances and energy to support tumor progression. To fuel these metabolic processes, extracellular matrix (ECM) plays a dominant role in supporting the mass transport and providing essential nutrients. Here, we report a fibrinogen and thrombin based coagulation system to construct an artificial ECM (aECM) for selectively cutting-off the tumor metabolic flux. Once a micro-wound is induced, a cascaded gelation of aECM can be triggered to besiege the tumor. Studies on cell behaviors and metabolomics reveal that aECM cuts off the mass transport and leads to a tumor specific starvation to inhibit tumor growth. In orthotopic and spontaneous murine tumor models, this physical barrier also hinders cancer cells from distant metastasis. The in vivo gelation provides an efficient approach to selectively alter the tumor mass transport. This strategy results in a 77% suppression of tumor growth. Most importantly, the gelation of aECM can be induced by clinical operations such as ultrasonic treatment, surgery or radiotherapy, implying this strategy is potential to be translated into a clinical combination regimen.


Assuntos
Materiais Biomiméticos/administração & dosagem , Matriz Extracelular/química , Neoplasias/terapia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/efeitos da radiação , Materiais Biomiméticos/química , Materiais Biomiméticos/efeitos da radiação , Linhagem Celular Tumoral/transplante , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Quimiorradioterapia/métodos , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos da radiação , Feminino , Fibrinogênio/administração & dosagem , Fibrinogênio/química , Fibrinogênio/efeitos da radiação , Géis , Humanos , Injeções Intravenosas , Metabolômica , Camundongos , Neoplasias/metabolismo , Trombina/administração & dosagem , Trombina/química , Trombina/efeitos da radiação , Terapia por Ultrassom/métodos , Ondas Ultrassônicas
3.
Nat Commun ; 11(1): 4818, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968060

RESUMO

Migrating cells move across diverse assemblies of extracellular matrix (ECM) that can be separated by micron-scale gaps. For membranes to protrude and reattach across a gap, actin filaments, which are relatively weak as single filaments, must polymerize outward from adhesion sites to push membranes towards distant sites of new adhesion. Here, using micropatterned ECMs, we identify T-Plastin, one of the most ancient actin bundling proteins, as an actin stabilizer that promotes membrane protrusions and enables bridging of ECM gaps. We show that T-Plastin widens and lengthens protrusions and is specifically enriched in active protrusions where F-actin is devoid of non-muscle myosin II activity. Together, our study uncovers critical roles of the actin bundler T-Plastin to promote protrusions and migration when adhesion is spatially-gapped.


Assuntos
Movimento Celular/fisiologia , Extensões da Superfície Celular/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Sistemas CRISPR-Cas , Adesão Celular , Linhagem Celular , Citoesqueleto/metabolismo , Matriz Extracelular/metabolismo , Técnicas de Inativação de Genes , Humanos , Cinética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/ultraestrutura , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/ultraestrutura , Miosinas/metabolismo , Pseudópodes/metabolismo , Receptor EphB2
4.
Mem Inst Oswaldo Cruz ; 115: e200007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935749

RESUMO

BACKGROUND: Behavioral and neurochemical alterations associated with toxoplasmosis may be influenced by the persistence of tissue cysts and activation of an immune response in the brain of Toxoplasma gondii-infected hosts. The cerebral extracellular matrix is organised as perineuronal nets (PNNs) that are both released and ensheath by some neurons and glial cells. There is evidences to suggest that PNNs impairment is a pathophysiological mechanism associated with neuropsychiatric conditions. However, there is a lack of information regarding the impact of parasitic infections on the PNNs integrity and how this could affect the host's behavior. OBJECTIVES: In this context, we aimed to analyse the impact of T. gondii infection on cyst burden, PNNs integrity, and possible effects in the locomotor activity of chronically infected mice. METHODS: We infected mice with T. gondii ME-49 strain. After thirty days, we assessed locomotor performance of animals using the open field test, followed by evaluation of cysts burden and PNNs integrity in four brain regions (primary and secondary motor cortices, prefrontal and somesthetic cortex) to assess the PNNs integrity using Wisteria floribunda agglutinin (WFA) labeling by immunohistochemical analyses. FINDINGS AND MAIN CONCLUSIONS: Our findings revealed a random distribution of cysts in the brain, the disruption of PNNs surrounding neurons in four areas of the cerebral cortex and hyperlocomotor behavior in T. gondii-infected mice. These results can contribute to elucidate the link toxoplasmosis with the establishment of neuroinflammatory response in neuropsychiatric disorders and to raise a discussion about the mechanisms related to changes in brain connectivity, with possible behavioral repercussions during chronic T. gondii infection.


Assuntos
Cerebelo/metabolismo , Matriz Extracelular/metabolismo , Neurônios Motores/citologia , Neurônios/patologia , Toxoplasmose Animal , Toxoplasmose/patologia , Animais , Cerebelo/citologia , Modelos Animais de Doenças , Camundongos , Neurônios Motores/metabolismo , Neurônios/metabolismo , Toxoplasma , Toxoplasmose/metabolismo
5.
Nat Commun ; 11(1): 4596, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929083

RESUMO

Earlier studies indicate that either the canonical or non-canonical pathways of inflammasome activation have a limited role on malaria pathogenesis. Here, we report that caspase-8 is a central mediator of systemic inflammation, septic shock in the Plasmodium chabaudi-infected mice and the P. berghei-induced experimental cerebral malaria (ECM). Importantly, our results indicate that the combined deficiencies of caspases-8/1/11 or caspase-8/gasdermin-D (GSDM-D) renders mice impaired to produce both TNFα and IL-1ß and highly resistant to lethality in these models, disclosing a complementary, but independent role of caspase-8 and caspases-1/11/GSDM-D in the pathogenesis of malaria. Further, we find that monocytes from malaria patients express active caspases-1, -4 and -8 suggesting that these inflammatory caspases may also play a role in the pathogenesis of human disease.


Assuntos
Caspase 8/metabolismo , Inflamação/patologia , Malária Cerebral/enzimologia , Animais , Encéfalo/patologia , Caspase 1/metabolismo , Células Dendríticas/metabolismo , Ativação Enzimática , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , Interferon gama/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Malária Cerebral/genética , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Plasmodium chabaudi/fisiologia , Baço/metabolismo , Receptores Toll-Like/metabolismo
6.
Nat Commun ; 11(1): 4283, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883967

RESUMO

Our understanding of the spatiotemporal regulation of cardiogenesis is hindered by the difficulties in modeling this complex organ currently by in vitro models. Here we develop a method to generate heart organoids from mouse embryonic stem cell-derived embryoid bodies. Consecutive morphological changes proceed in a self-organizing manner in the presence of the laminin-entactin (LN/ET) complex and fibroblast growth factor 4 (FGF4), and the resulting in vitro heart organoid possesses atrium- and ventricle-like parts containing cardiac muscle, conducting tissues, smooth muscle and endothelial cells that exhibited myocardial contraction and action potentials. The heart organoids exhibit ultrastructural, histochemical and gene expression characteristics of considerable similarity to those of developmental hearts in vivo. Our results demonstrate that this method not only provides a biomimetic model of the developing heart-like structure with simplified differentiation protocol, but also represents a promising research tool with a broad range of applications, including drug testing.


Assuntos
Matriz Extracelular/metabolismo , Fator 4 de Crescimento de Fibroblastos/metabolismo , Coração , Células-Tronco Embrionárias Murinas/metabolismo , Organoides , Potenciais de Ação , Diamino Aminoácidos/metabolismo , Animais , Biomimética/métodos , Diferenciação Celular , Linhagem Celular , Células Endoteliais , Coração/crescimento & desenvolvimento , Coração/fisiologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Contração Miocárdica , Miocárdio , Organoides/citologia , Organoides/crescimento & desenvolvimento , Organoides/ultraestrutura
7.
Gene ; 761: 145024, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32755659

RESUMO

Understanding how various pathologies of breast cancer respond to their environment may be imperative in the creation of novel therapeutic targets. Central to the organisation and behaviour of cells within the tumour microenvironment is the extracellular matrix (ECM), a meshwork of fibrous proteins and glycoproteins that directly influences cell behaviour and the bioavailability of signalling molecules. Our appreciation on how the composition of the ECM can influence cancer behaviour has evolved significantly and although we are highly cognisant of the dramatic impact the ECM can have on cancer cell behaviour, we continue to neglect this during diagnosis and treatment. In the following study, we aimed to identify how three breast cancer cell lines respond functionally and genetically to common components of the ECM. Using real time and end point assays we have identified similar patterns of behaviour among the three breast cancer cell lines in response to commonly found ECM components of the breast. Using a selected gene panel, we have been able to identify cell line specific changes in gene differentiation when breast cancer cells are in contact with these elements. Although the response of our cells to these elements differ at the genetic level, their functional responses are consistent. This work adds to the growing arguments that highlight a need for histologically assessing ECM composition of breast tumours. In particular monitoring of fibrous protein deposition at the site of malignancy could provide critical information during clinical assessment influencing disease prognosis and treatment decisions for breast cancer patients.


Assuntos
Neoplasias da Mama/genética , Colágeno/genética , Fibronectinas/genética , Mama/patologia , Linhagem Celular Tumoral , Colágeno/metabolismo , Colágeno Tipo I/genética , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Feminino , Fibronectinas/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Genótipo , Glicoproteínas/genética , Humanos , Fenótipo , Prognóstico , Transdução de Sinais , Microambiente Tumoral
8.
Life Sci ; 259: 118191, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32777302

RESUMO

Numerous population studies conducted worldwide indicate that the prevalence of asthma is higher in obese versus lean individuals. It has been reported that sensitized lean mice has a better recovery of lung inflammation in asthma. Extracellular matrix (ECM) plays an essential role in the structural support of the lungs regulating the airways diameter, thus preventing its collapse during expiration. ECM renewal by metalloproteinase (MMPs) enzymes is critical for pulmonary biology. There seems to be an imbalance of MMPs activity in asthma and obesity, which can impair the lung remodeling process. In this study, we characterized the pulmonary ECM of obese and lean mice, non-sensitized and sensitized with ovalbumin (OVA). Pharmacological intervention was performed by using anti-TNF-α, and MMP-8 and MMP-9 inhibitors in obese and lean sensitized mice. Activity of MMPs was assessed by gelatinase electrophorese, western blotting and zymogram in situ. Unbalance of MMP-2, MMP-8, MMP-9 and MMP-12 was detected in lung tissue of OVA-sensitized obese mice, which was accompanied by high degradation, corroborating an excessive deposition of types I and III collagen in pulmonary matrix of obese animals. Inhibitions of TNF-α and MMP-9 reduced this MMP imbalance, clearly suggesting a positive effect on pulmonary ECM. Obese and lean mice presented diverse phenotype of asthma regarding the ECM compounds and the inhibition of MMPs pathway could be a good alternative to regulate the activity in ECM lungs of asthmatic obese individuals.


Assuntos
Asma/etiologia , Asma/metabolismo , Metaloproteases/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Líquido da Lavagem Broncoalveolar/citologia , Matriz Extracelular/metabolismo , Inflamação/metabolismo , Pulmão/patologia , Masculino , Metaloproteinase 8 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina/imunologia , Inibidores de Proteases/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores
9.
PLoS Comput Biol ; 16(8): e1008105, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817654

RESUMO

Epithelial sheets define organ architecture during development. Here, we employed an iterative multiscale computational modeling and quantitative experimental approach to decouple direct and indirect effects of actomyosin-generated forces, nuclear positioning, extracellular matrix, and cell-cell adhesion in shaping Drosophila wing imaginal discs. Basally generated actomyosin forces generate epithelial bending of the wing disc pouch. Surprisingly, acute pharmacological inhibition of ROCK-driven actomyosin contractility does not impact the maintenance of tissue height or curved shape. Computational simulations show that ECM tautness provides only a minor contribution to modulating tissue shape. Instead, passive ECM pre-strain serves to maintain the shape independent from actomyosin contractility. These results provide general insight into how the subcellular forces are generated and maintained within individual cells to induce tissue curvature. Thus, the results suggest an important design principle of separable contributions from ECM prestrain and actomyosin tension during epithelial organogenesis and homeostasis.


Assuntos
Actomiosina/metabolismo , Epitélio/anatomia & histologia , Matriz Extracelular/metabolismo , Animais , Drosophila/anatomia & histologia , Drosophila/embriologia , Drosophila/metabolismo , Epitélio/metabolismo , Fosforilação , Asas de Animais/anatomia & histologia , Asas de Animais/embriologia , Asas de Animais/metabolismo
10.
Int J Nanomedicine ; 15: 4943-4956, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764927

RESUMO

Background: Hydroxyapatite (HA) [Ca5(PO4)3(OH)] is a naturally occurring calcium phosphate which makes up 60-70% of the dry weight of human bones. Nano-scale HA particles are increasingly being used as carriers for controlled and targeted delivery of bioactive agents like drugs, proteins, and nucleic acids due to their high porosity, negative charge, and biodegradability. Purpose: Although much effort has been devoted to understanding the delivery kinetics and effects of the payloads in such carriers, a thorough understanding of the influence of the carriers themselves is lacking. Methods: HA particles (300 µg/mL) were administered to primary human dermal fibroblasts (HDFs). The uptake and intracellular localization of the particles were determined by flow cytometry, confocal imaging, and transmission electron microscopy (TEM). Immunological assays and PCR were performed to determine the levels of pro-inflammatory cytokines and collagens in cell lysates and media supernatant. Results: The current study explores the effects of poly-dispersed HA particles on primary HDFs as a model system. The majority of the particles were determined to range between 150 and 200 nm in diameter. Upon exposure to HA suspensions, primary HDFs internalized the particles by endocytosis within 6 hours of exposure, showing maximum uptake at 72 hours following which the particles were exocytosed by 168 hours. This correlated to reduced secretion of various pro-inflammatory and pro-collagenic cytokines. Biochemical analysis further revealed a reduction in Type I collagen expression and secretion. Conclusion: HA particles have an immune-modulatory effect on dermal fibroblasts and reduce collagen production, which may impact the integrity of the extracellular matrix (ECM). This study demonstrates the need to consider the secondary effects of particulate carriers like HA, beyond basic cytotoxicity, in the specific tissue environment where the intended function is to be realized.


Assuntos
Colágeno/metabolismo , Durapatita/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Pele/citologia , Colágeno Tipo I/metabolismo , Citocinas/metabolismo , Durapatita/química , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Humanos
11.
Nat Commun ; 11(1): 3953, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769974

RESUMO

Many important cell types in adult vertebrates have a mesenchymal origin, including fibroblasts and vascular mural cells. Although their biological importance is undisputed, the level of mesenchymal cell heterogeneity within and between organs, while appreciated, has not been analyzed in detail. Here, we compare single-cell transcriptional profiles of fibroblasts and vascular mural cells across four murine muscular organs: heart, skeletal muscle, intestine and bladder. We reveal gene expression signatures that demarcate fibroblasts from mural cells and provide molecular signatures for cell subtype identification. We observe striking inter- and intra-organ heterogeneity amongst the fibroblasts, primarily reflecting differences in the expression of extracellular matrix components. Fibroblast subtypes localize to discrete anatomical positions offering novel predictions about physiological function(s) and regulatory signaling circuits. Our data shed new light on the diversity of poorly defined classes of cells and provide a foundation for improved understanding of their roles in physiological and pathological processes.


Assuntos
Diferenciação Celular , Fibroblastos/fisiologia , Células-Tronco Mesenquimais/fisiologia , Miócitos de Músculo Liso/fisiologia , Pericitos/fisiologia , Animais , Separação Celular , Vasos Coronários/citologia , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Citometria de Fluxo , Intestinos/irrigação sanguínea , Intestinos/citologia , Masculino , Camundongos , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/citologia , Músculo Liso Vascular/citologia , Miocárdio/citologia , Miócitos de Músculo Liso/citologia , Pericitos/citologia , RNA-Seq , Análise de Célula Única , Bexiga Urinária/irrigação sanguínea , Bexiga Urinária/citologia
12.
Nature ; 584(7822): 535-546, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848221

RESUMO

Substantial research over the past two decades has established that extracellular matrix (ECM) elasticity, or stiffness, affects fundamental cellular processes, including spreading, growth, proliferation, migration, differentiation and organoid formation. Linearly elastic polyacrylamide hydrogels and polydimethylsiloxane (PDMS) elastomers coated with ECM proteins are widely used to assess the role of stiffness, and results from such experiments are often assumed to reproduce the effect of the mechanical environment experienced by cells in vivo. However, tissues and ECMs are not linearly elastic materials-they exhibit far more complex mechanical behaviours, including viscoelasticity (a time-dependent response to loading or deformation), as well as mechanical plasticity and nonlinear elasticity. Here we review the complex mechanical behaviours of tissues and ECMs, discuss the effect of ECM viscoelasticity on cells, and describe the potential use of viscoelastic biomaterials in regenerative medicine. Recent work has revealed that matrix viscoelasticity regulates these same fundamental cell processes, and can promote behaviours that are not observed with elastic hydrogels in both two- and three-dimensional culture microenvironments. These findings have provided insights into cell-matrix interactions and how these interactions differentially modulate mechano-sensitive molecular pathways in cells. Moreover, these results suggest design guidelines for the next generation of biomaterials, with the goal of matching tissue and ECM mechanics for in vitro tissue models and applications in regenerative medicine.


Assuntos
Elasticidade , Matriz Extracelular/metabolismo , Substâncias Viscoelásticas , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Técnicas de Cultura de Células , Forma Celular , Matriz Extracelular/química , Humanos , Mecanotransdução Celular , Células-Tronco Mesenquimais/citologia , Modelos Biológicos , Medicina Regenerativa
13.
Int J Nanomedicine ; 15: 5825-5838, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821104

RESUMO

Background and Purpose: The extracellular matrix (ECM) derived from bone marrow mesenchymal stem cells (BMSCs) has been used in regenerative medicine because of its good biological activity; however, its poor mechanical properties limit its application in bone regeneration. The purpose of this study is to construct a three dimensional-printed hydroxyapatite (3D-HA)/BMSC-ECM composite scaffold that not only has biological activity but also sufficient mechanical strength and reasonably distributed spatial structure. Methods: A BMSC-ECM was first extracted and formed into micron-sized particles, and then the ECM particles were modified onto the surface of 3D-HA scaffolds using an innovative linking method to generate composite 3D-HA/BMSC-ECM scaffolds. The 3D-HA scaffolds were used as the control group. The basic properties, biocompatibility and osteogenesis ability of both scaffolds were tested in vitro. Finally, a critical skull defect rat model was created and the osteogenesis effect of the scaffolds was evaluated in vivo. Results: The compressive modulus of the composite scaffolds reached 9.45±0.32 MPa, which was similar to that of the 3D-HA scaffolds (p>0.05). The pore size of the two scaffolds was 305±47 um and 315±34 um (p>0.05), respectively. A CCK-8 assay indicated that the scaffolds did not have cytotoxicity. The composite scaffolds had good cell adhesion ability, with a cell adhesion rate of up to 76.00±6.17% after culturing for 7 hours, while that of the 3D-HA scaffolds was 51.85±4.77% (p<0.01). In addition, the composite scaffold displayed higher alkaline phosphatase (ALP) activity, osteogenesis-related mRNA expression, and calcium nodule formation, thus confirming that the composite scaffolds had good osteogenic activity. The composite scaffolds exhibited good bone repair in vivo and were superior to the 3D-HA scaffolds. Conclusion: We conclude that BMSC-ECM is a good osteogenic material and that the composite scaffolds have good osteogenic ability, which provides a new method and concept for the repair of bone defects.


Assuntos
Durapatita/farmacologia , Matriz Extracelular/metabolismo , Células-Tronco Mesenquimais/citologia , Tecidos Suporte/química , Animais , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Hidrodinâmica , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Osteogênese/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos
14.
Proc Natl Acad Sci U S A ; 117(32): 19033-19044, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32709748

RESUMO

Therapeutic factors secreted by mesenchymal stem cells (MSCs) promote angiogenesis in vivo. However, delivery of MSCs in the absence of a cytoprotective environment offers limited efficacy due to low cell retention, poor graft survival, and the nonmaintenance of a physiologically relevant dose of growth factors at the injury site. The delivery of stem cells on an extracellular matrix (ECM)-based platform alters cell behavior, including migration, proliferation, and paracrine activity, which are essential for angiogenesis. We demonstrate the biophysical and biochemical effects of preconditioning human MSCs (hMSCs) for 96 h on a three-dimensional (3D) ECM-based microgel platform. By altering the macromolecular concentration surrounding cells in the microgels, the proangiogenic phenotype of hMSCs can be tuned in a controlled manner through cell-driven changes in extracellular stiffness and "outside-in" integrin signaling. The softest microgels were tested at a low cell dose (5 × 104 cells) in a preclinical hindlimb ischemia model showing accelerated formation of new blood vessels with a reduced inflammatory response impeding progression of tissue damage. Molecular analysis revealed that several key mediators of angiogenesis were up-regulated in the low-cell-dose microgel group, providing a mechanistic insight of pathways modulated in vivo. Our research adds to current knowledge in cell-encapsulation strategies by highlighting the importance of preconditioning or priming the capacity of biomaterials through cell-material interactions. Obtaining therapeutic efficacy at a low cell dose in the microgel platform is a promising clinical route that would aid faster tissue repair and reperfusion in "no-option" patients suffering from peripheral arterial diseases, such as critical limb ischemia (CLI).


Assuntos
Células-Tronco Mesenquimais/química , Células-Tronco Mesenquimais/citologia , Microgéis/química , Neovascularização Fisiológica , Animais , Proliferação de Células , Células Imobilizadas/química , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Membro Posterior/irrigação sanguínea , Membro Posterior/metabolismo , Membro Posterior/cirurgia , Humanos , Integrinas/genética , Integrinas/metabolismo , Isquemia/fisiopatologia , Isquemia/cirurgia , Isquemia/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Nus
16.
Arterioscler Thromb Vasc Biol ; 40(9): 2212-2226, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32640908

RESUMO

OBJECTIVE: The ductus arteriosus (DA) is a fetal artery connecting the aorta and pulmonary arteries. Progressive matrix remodeling, that is, intimal thickening (IT), occurs in the subendothelial region of DA to bring anatomic DA closure. IT is comprised of multiple ECMs (extracellular matrices) and migrated smooth muscle cells (SMCs). Because glycoprotein fibulin-1 binds to multiple ECMs and regulates morphogenesis during development, we investigated the role of fibulin-1 in DA closure. Approach and Results: Fibulin-1-deficient (Fbln1-/-) mice exhibited patent DA with hypoplastic IT. An unbiased transcriptome analysis revealed that EP4 (prostaglandin E receptor 4) stimulation markedly increased fibulin-1 in DA-SMCs via phospholipase C-NFκB (nuclear factor κB) signaling pathways. Fluorescence-activated cell sorting (FACS) analysis demonstrated that fibulin-1 binding protein versican was derived from DA-endothelial cells (ECs). We examined the effect of fibulin-1 on directional migration toward ECs in association with versican by using cocultured DA-SMCs and ECs. EP4 stimulation promoted directional DA-SMC migration toward ECs, which was attenuated by either silencing fibulin-1 or versican. Immunofluorescence demonstrated that fibulin-1 and versican V0/V1 were coexpressed at the IT of wild-type DA, whereas 30% of versican-deleted mice lacking a hyaluronan binding site displayed patent DA. Fibulin-1 expression was attenuated in the EP4-deficient mouse (Ptger4-/-) DA, which exhibits patent DA with hypoplastic IT, and fibulin-1 protein administration restored IT formation. In human DA, fibulin-1 and versican were abundantly expressed in SMCs and ECs, respectively. CONCLUSIONS: Fibulin-1 contributes to DA closure by forming an environment favoring directional SMC migration toward the subendothelial region, at least, in part, in combination with EC-derived versican and its binding partner hyaluronan.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Permeabilidade do Canal Arterial/metabolismo , Canal Arterial/metabolismo , Células Endoteliais/metabolismo , Matriz Extracelular/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Proteínas de Ligação ao Cálcio/deficiência , Proteínas de Ligação ao Cálcio/genética , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Canal Arterial/anormalidades , Permeabilidade do Canal Arterial/genética , Permeabilidade do Canal Arterial/patologia , Células Endoteliais/patologia , Matriz Extracelular/genética , Matriz Extracelular/patologia , Humanos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/patologia , NF-kappa B/metabolismo , Técnicas de Cultura de Órgãos , Proteína Quinase C/metabolismo , Ratos Wistar , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Transdução de Sinais , Fosfolipases Tipo C/metabolismo
17.
Arterioscler Thromb Vasc Biol ; 40(9): 2195-2211, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32698686

RESUMO

OBJECTIVE: To delineate temporal and spatial dynamics of vascular smooth muscle cell (SMC) transcriptomic changes during aortic aneurysm development in Marfan syndrome (MFS). Approach and Results: We performed single-cell RNA sequencing to study aortic root/ascending aneurysm tissue from Fbn1C1041G/+ (MFS) mice and healthy controls, identifying all aortic cell types. A distinct cluster of transcriptomically modulated SMCs (modSMCs) was identified in adult Fbn1C1041G/+ mouse aortic aneurysm tissue only. Comparison with atherosclerotic aortic data (ApoE-/- mice) revealed similar patterns of SMC modulation but identified an MFS-specific gene signature, including plasminogen activator inhibitor-1 (Serpine1) and Kruppel-like factor 4 (Klf4). We identified 481 differentially expressed genes between modSMC and SMC subsets; functional annotation highlighted extracellular matrix modulation, collagen synthesis, adhesion, and proliferation. Pseudotime trajectory analysis of Fbn1C1041G/+ SMC/modSMC transcriptomes identified genes activated differentially throughout the course of phenotype modulation. While modSMCs were not present in young Fbn1C1041G/+ mouse aortas despite small aortic aneurysm, multiple early modSMCs marker genes were enriched, suggesting activation of phenotype modulation. modSMCs were not found in nondilated adult Fbn1C1041G/+ descending thoracic aortas. Single-cell RNA sequencing from human MFS aortic root aneurysm tissue confirmed analogous SMC modulation in clinical disease. Enhanced expression of TGF-ß (transforming growth factor beta)-responsive genes correlated with SMC modulation in mouse and human data sets. CONCLUSIONS: Dynamic SMC phenotype modulation promotes extracellular matrix substrate modulation and aortic aneurysm progression in MFS. We characterize the disease-specific signature of modSMCs and provide temporal, transcriptomic context to the current understanding of the role TGF-ß plays in MFS aortopathy. Collectively, single-cell RNA sequencing implicates TGF-ß signaling and Klf4 overexpression as potential upstream drivers of SMC modulation.


Assuntos
Aneurisma Aórtico/genética , Fibrilina-1/genética , Perfilação da Expressão Gênica , Síndrome de Marfan/complicações , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Análise de Célula Única , Transcriptoma , Animais , Aorta/metabolismo , Aorta/patologia , Aneurisma Aórtico/metabolismo , Aneurisma Aórtico/patologia , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Modelos Animais de Doenças , Progressão da Doença , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Predisposição Genética para Doença , Masculino , Síndrome de Marfan/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Liso Vascular/patologia , Mutação , Miócitos de Músculo Liso/patologia , Fenótipo , RNA-Seq , Fatores de Tempo , Remodelação Vascular/genética
18.
J Vis Exp ; (160)2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32658183

RESUMO

Significant progress has been made in treating cancer with immunotherapy, although a large number of cancers remain resistant to treatment. A limited number of assays allow for direct monitoring and mechanistic insights into the interactions between tumor and immune cells, amongst which, T-cells play a significant role in executing the cytotoxic response of the adaptive immune system to cancer cells. Most assays are based on two-dimensional (2D) co-culture of cells due to the relative ease of use but with limited representation of the invasive growth phenotype, one of the hallmarks of cancer cells. Current three-dimensional (3D) co-culture systems either require special equipment or separate monitoring for invasion of co-cultured cancer cells and interacting T-cells. Here we describe an approach to simultaneously monitor the invasive behavior in 3D of cancer cell spheroids and T-cell cytotoxicity in co-culture. Spheroid formation is driven by enhanced cell-cell interactions in scaffold-free agarose microwell casts with U-shaped bottoms. Both T-cell co-culture and cancer cell invasion into type I collagen matrix are performed within the microwells of the agarose casts without the need to transfer the cells, thus maintaining an intact 3D co-culture system throughout the assay. The collagen matrix can be separated from the agarose cast, allowing for immunofluorescence (IF) staining and for confocal imaging of cells. Also, cells can be isolated for further growth or subjected to analyses such as for gene expression or fluorescence activated cell sorting (FACS). Finally, the 3D co-culture can be analyzed by immunohistochemistry (IHC) after embedding and sectioning. Possible modifications of the assay include altered compositions of the extracellular matrix (ECM) as well as the inclusion of different stromal or immune cells with the cancer cells.


Assuntos
Técnicas de Cocultura/métodos , Linfócitos T Citotóxicos/citologia , Comunicação Celular , Linhagem Celular Tumoral , Colágeno Tipo I/metabolismo , Matriz Extracelular/metabolismo , Humanos , Invasividade Neoplásica , Esferoides Celulares/patologia
19.
Int J Nanomedicine ; 15: 4333-4350, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606681

RESUMO

Background: Different diseases affect both mechanical and chemical features of the involved tissue, enhancing the symptoms. Methods: In this study, using atomic force microscopy, we mechanically characterized human ovarian tissues with four distinct pathological conditions: mucinous, serous, and mature teratoma tumors, and non-tumorous endometriosis. Mechanical elasticity profiles were quantified and the resultant data were categorized using K-means clustering method, as well as fuzzy C-means, to evaluate elastic moduli of cellular and non-cellular parts of diseased tissues and compare them among four disease conditions. Samples were stained by hematoxylin-eosin staining to further study the content of different locations of tissues. Results: Pathological state vastly influenced the mechanical properties of the ovarian tissues. Significant alterations among elastic moduli of both cellular and non-cellular parts were observed. Mature teratoma tumors commonly composed of multiple cell types and heterogeneous ECM structure showed the widest range of elasticity profile and the stiffest average elastic modulus of 14 kPa. Samples of serous tumors were the softest tissues with elastic modulus of only 400 Pa for the cellular part and 5 kPa for the ECM. Tissues of other two diseases were closer in mechanical properties as mucinous tumors were insignificantly stiffer than endometriosis in cellular part, 1300 Pa compared to 1000 Pa, with the ECM average elastic modulus of 8 kPa for both. Conclusion: The higher incidence of carcinoma out of teratoma and serous tumors may be related to the intense alteration of mechanical features of the cellular and the ECM, serving as a potential risk factor which necessitates further investigation.


Assuntos
Microscopia de Força Atômica , Nanopartículas/química , Ovário/patologia , Ovário/ultraestrutura , Adulto , Fenômenos Biomecânicos , Módulo de Elasticidade , Matriz Extracelular/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade
20.
Nat Commun ; 11(1): 3677, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699279

RESUMO

Through the formation of concentration gradients, morphogens drive graded responses to extracellular signals, thereby fine-tuning cell behaviors in complex tissues. Here we show that the chemokine CXCL13 forms both soluble and immobilized gradients. Specifically, CXCL13+ follicular reticular cells form a small-world network of guidance structures, with computer simulations and optimization analysis predicting that immobilized gradients created by this network promote B cell trafficking. Consistent with this prediction, imaging analysis show that CXCL13 binds to extracellular matrix components in situ, constraining its diffusion. CXCL13 solubilization requires the protease cathepsin B that cleaves CXCL13 into a stable product. Mice lacking cathepsin B display aberrant follicular architecture, a phenotype associated with effective B cell homing to but not within lymph nodes. Our data thus suggest that reticular cells of the B cell zone generate microenvironments that shape both immobilized and soluble CXCL13 gradients.


Assuntos
Linfócitos B/imunologia , Microambiente Celular/imunologia , Quimiocina CXCL13/metabolismo , Células Dendríticas Foliculares/imunologia , Imunidade Adaptativa , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Catepsina B/genética , Catepsina B/metabolismo , Linhagem Celular , Quimiocina CXCL13/imunologia , Simulação por Computador , Células Dendríticas Foliculares/citologia , Células Dendríticas Foliculares/metabolismo , Matriz Extracelular/metabolismo , Humanos , Camundongos , Camundongos Knockout , Microscopia de Fluorescência , Modelos Biológicos , Tonsila Palatina/citologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Células Estromais/imunologia , Células Estromais/metabolismo
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