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1.
Science ; 370(6512): 113-116, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33004519

RESUMO

Animal development entails the organization of specific cell types in space and time, and spatial patterns must form in a robust manner. In the zebrafish spinal cord, neural progenitors form stereotypic patterns despite noisy morphogen signaling and large-scale cellular rearrangements during morphogenesis and growth. By directly measuring adhesion forces and preferences for three types of endogenous neural progenitors, we provide evidence for the differential adhesion model in which differences in intercellular adhesion mediate cell sorting. Cell type-specific combinatorial expression of different classes of cadherins (N-cadherin, cadherin 11, and protocadherin 19) results in homotypic preference ex vivo and patterning robustness in vivo. Furthermore, the differential adhesion code is regulated by the sonic hedgehog morphogen gradient. We propose that robust patterning during tissue morphogenesis results from interplay between adhesion-based self-organization and morphogen-directed patterning.


Assuntos
Padronização Corporal/fisiologia , Caderinas/metabolismo , Adesão Celular/fisiologia , Células-Tronco Neurais/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Animais , Padronização Corporal/genética , Caderinas/genética , Adesão Celular/genética , Medula Espinal/crescimento & desenvolvimento , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
2.
Vaccine ; 38(48): 7629-7637, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33071000

RESUMO

This work demonstrates the presence of immune regulatory cells in the cervical lymph nodes draining Bacillus Calmette-Guérin (BCG) vaccinated site on the dorsum of the ear in guinea pigs. It is shown that whole cervical lymph node cells did not proliferate in vitro in the presence of soluble mycobacterial antigens (PPD or leprosin) despite being responsive to whole mycobacteria. Besides, T cells from these lymph nodes separated as a non-adherent fraction on a nylon wool column, proliferated to PPD in the presence of autologous antigen presenting cells. Interestingly, addition of as low as 20% nylon wool adherent cells to these, sharply decreased the proliferation by 83%. Looking into what cells in the adherent fraction suppressed the proliferation, it was found that neither the T cell nor the macrophage enriched cell fractions of this population individually showed suppressive effect, indicating that their co-presence was necessary for the suppression. Since BCG induced granulomas resolve much faster than granulomas induced by other mycobacteria such as Mycobacterium leprae the present experimental findings add to the existing evidence that intradermal BCG vaccination influences subsequent immune responses in the host and may further stress upon its beneficial role seen in Covid-19 patients.


Assuntos
Antígenos de Bactérias/farmacologia , Vacina BCG/farmacologia , Granuloma/imunologia , Linfonodos/imunologia , Linfócitos T/imunologia , Tuberculina/farmacologia , Animais , Células Apresentadoras de Antígenos/efeitos dos fármacos , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/microbiologia , Adesão Celular , Proliferação de Células , Infecções por Coronavirus/prevenção & controle , Orelha , Feminino , Granuloma/microbiologia , Cobaias , Humanos , Injeções Intradérmicas , Linfonodos/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/microbiologia , Masculino , Mycobacterium bovis/imunologia , Mycobacterium leprae/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Remissão Espontânea , Linfócitos T/classificação , Linfócitos T/efeitos dos fármacos , Linfócitos T/microbiologia
3.
Sheng Li Xue Bao ; 72(5): 605-616, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33106831

RESUMO

Epithelial-mesenchymal transition (EMT) plays an important role in the development and pathogenesis of respiratory system. Epithelial cells are characterized by well-developed, intercellular contacts, whereas EMT triggers the sequential destabilization of cell-cell adhesive junctions. The dynamic remodeling of the epithelial cell adhesion molecules is important for maintaining the integrity and normal function of epithelium. This paper reviews the research progress of EMT in lung development, lung injury repair and chronic lung diseases, and summarizes the effect of cell junctions and cell adhesion molecules on EMT molecular events.


Assuntos
Transição Epitelial-Mesenquimal , Sistema Respiratório , Adesão Celular , Moléculas de Adesão Celular , Células Epiteliais
4.
Folia Biol (Praha) ; 66(3): 91-103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33069188

RESUMO

The most recent genome-editing system called CRISPR-Cas9 (clustered regularly interspaced short palindromic repeat system with associated protein 9-nuclease) was employed to delete four non-essential genes (i.e., Caeco1, Caidh1, Carom2, and Cataf10) individually to establish their gene functionality annotations in pathogen Candida albicans. The biological roles of these genes were investigated with respect to the cell wall integrity and biogenesis, calcium/calcineurin pathways, susceptibility of mutants towards temperature, drugs and salts. All the mutants showed increased vulnerability compared to the wild-type background strain towards the cell wall-perturbing agents, (antifungal) drugs and salts. All the mutants also exhibited repressed and defective hyphal growth and smaller colony size than control CA14. The cell cycle of all the mutants decreased enormously except for those with Carom2 deletion. The budding index and budding size also increased for all mutants with altered bud shape. The disposition of the mutants towards cell wall-perturbing enzymes disclosed lower survival and more rapid cell wall lysis events than in wild types. The pathogenicity and virulence of the mutants was checked by adhesion assay, and strains lacking rom2 and eco1 were found to possess the least adhesion capacity, which is synonymous to their decreased pathogenicity and virulence.


Assuntos
Candida albicans/fisiologia , Proteínas Fúngicas/fisiologia , Genes Fúngicos , Acetiltransferases/deficiência , Acetiltransferases/genética , Acetiltransferases/fisiologia , Antifúngicos/farmacologia , Sistemas CRISPR-Cas , Cálcio/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candida albicans/patogenicidade , Cátions/farmacologia , Adesão Celular , Ciclo Celular , Parede Celular/efeitos dos fármacos , Quitinases/farmacologia , Dano ao DNA , Proteínas Fúngicas/genética , Deleção de Genes , Glucana Endo-1,3-beta-D-Glucosidase/farmacologia , Hifas/crescimento & desenvolvimento , Isocitrato Desidrogenase/deficiência , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/fisiologia , Fases de Leitura Aberta , Reprodução Assexuada , Fatores Associados à Proteína de Ligação a TATA/deficiência , Fatores Associados à Proteína de Ligação a TATA/genética , Fatores Associados à Proteína de Ligação a TATA/fisiologia , Virulência/genética
5.
Nat Commun ; 11(1): 5426, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110060

RESUMO

Novel atherosclerosis models are needed to guide clinical therapy. Here, we report an in vitro model of early atherosclerosis by fabricating and perfusing multi-layer arteriole-scale human tissue-engineered blood vessels (TEBVs) by plastic compression. TEBVs maintain mechanical strength, vasoactivity, and nitric oxide (NO) production for at least 4 weeks. Perfusion of TEBVs at a physiological shear stress with enzyme-modified low-density-lipoprotein (eLDL) with or without TNFα promotes monocyte accumulation, reduces vasoactivity, alters NO production, which leads to endothelial cell activation, monocyte accumulation, foam cell formation and expression of pro-inflammatory cytokines. Removing eLDL leads to recovery of vasoactivity, but not loss of foam cells or recovery of permeability, while pretreatment with lovastatin or the P2Y11 inhibitor NF157 reduces monocyte accumulation and blocks foam cell formation. Perfusion with blood leads to increased monocyte adhesion. This atherosclerosis model can identify the role of drugs on specific vascular functions that cannot be assessed in vivo.


Assuntos
Arteríolas/fisiopatologia , Aterosclerose/fisiopatologia , Arteríolas/química , Arteríolas/citologia , Aterosclerose/genética , Aterosclerose/metabolismo , Fenômenos Biomecânicos , Adesão Celular , Proliferação de Células , Células Cultivadas , Células Espumosas/citologia , Células Espumosas/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Modelos Biológicos , Monócitos/citologia , Monócitos/metabolismo , Óxido Nítrico/metabolismo , Engenharia Tecidual , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
6.
Int J Nanomedicine ; 15: 6373-6383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32904686

RESUMO

Background: The treatment of tendon injuries remains a challenging problem in clinical due to their slow and insufficient natural healing process. Scaffold-based tissue engineering provides a promising strategy to facilitate tendon healing and regeneration. However, many tissue engineering scaffolds have failed due to their poor and unstable mechanical properties. To address this, we fabricated nanofibrous polycaprolactone/methacrylated poly(trimethylene carbonate) (PCL/PTMC-MA) composite scaffolds via electrospinning. Materials and Methods: PTMC-MA was characterized by nuclear magnetic resonance. Fiber morphology of composite scaffolds was evaluated using scanning electron microscopy. The monotonic tensile test was performed for determining the mechanical properties of composite scaffolds. Cell viability and collagen deposition were assessed via PrestoBlue assay and enzyme-linked immunosorbent assay, respectively. Results: These PCL/PTMC-MA composite scaffolds had an increase in mechanical properties as PTMC-MA content increase. After photo-crosslinking, they showed further enhanced mechanical properties including creep resistance, which was superior to pure PCL scaffolds. It is worth noting that photo-crosslinked PCL/PTMC-MA (1:3) composite scaffolds had a Young's modulus of 31.13 ± 1.30 MPa and Max stress at break of 23.80 ± 3.44 MPa that were comparable with the mechanical properties of native tendon (Young's modulus 20-1200 MPa, max stress at break 5-100 MPa). In addition, biological experiments demonstrated that PCL/PTMC-MA composite scaffolds were biocompatible for cell adhesion, proliferation, and differentiation.


Assuntos
Células-Tronco Mesenquimais/citologia , Nanofibras/química , Fotoquímica/métodos , Tecidos Suporte/química , Animais , Adesão Celular , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Colágeno/metabolismo , Dioxanos/química , Teste de Materiais , Camundongos Endogâmicos C57BL , Poliésteres/química , Polímeros/química , Regeneração , Tendões/fisiologia
7.
Cell Prolif ; 53(10): e12899, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32896929

RESUMO

OBJECTIVES: Stem cell niche regulated the renewal and differentiation of germline stem cells (GSCs) in Drosophila. Previously, we and others identified a series of genes encoding ribosomal proteins that may contribute to the self-renewal and differentiation of GSCs. However, the mechanisms that maintain and differentiate GSCs in their niches were not well understood. MATERIALS AND METHODS: Flies were used to generate tissue-specific gene knockdown. Small interfering RNAs were used to knockdown genes in S2 cells. qRT-PCR was used to examine the relative mRNA expression level. TUNEL staining or flow cytometry assays were used to detect cell survival. Immunofluorescence was used to determine protein localization and expression pattern. RESULTS: Herein, using a genetic manipulation approach, we investigated the role of ribosomal protein S13 (RpS13) in testes and S2 cells. We reported that RpS13 was required for the self-renewal and differentiation of GSCs. We also demonstrated that RpS13 regulated cell proliferation and apoptosis. Mechanistically, we showed that RpS13 regulated the expression of ribosome subunits and could moderate the expression of the Rho1, DE-cad and Arm proteins. Notably, Rho1 imitated the phenotype of RpS13 in both Drosophila testes and S2 cells, and recruited cell adhesions, which was mediated by the DE-cad and Arm proteins. CONCLUSION: These findings uncover a novel mechanism of RpS13 that mediates Rho1 signals in the stem cell niche of the Drosophila testis.


Assuntos
Proteínas de Drosophila/metabolismo , Proteínas Ribossômicas/metabolismo , Transdução de Sinais , Testículo/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Animais , Apoptose , Adesão Celular , Diferenciação Celular , Proliferação de Células , Autorrenovação Celular , Drosophila/metabolismo , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Células Germinativas/citologia , Masculino , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Nicho de Células-Tronco , Células-Tronco/citologia , Células-Tronco/metabolismo , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/genética
8.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(8): 750-754, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32958132

RESUMO

Integrins are transmembrane glycoproteins expressed on the surface of various cells. They can conduct bidirectional signal transduction across cell membranes, exchange information between extracellular matrix proteins and intracellular molecules, and regulate cell adhesion and activation. During cancer development, integrins mediate crucial regulatory functions in anti-tumor response including tumor antigen uptake, activation of tumor-specific T cells, leukocyte trafficking into the tumor site and tumor cell killing. We provided a comprehensive overview of the structure of integrins, immune regulation, effects of integrins on tumor immunity and covered in vivo and in vitro studies of tissue culture, animal models of human diseases and gene knockout animals as well as the progress in clinical diagnosis and therapy of tumors.


Assuntos
Integrinas , Neoplasias , Animais , Adesão Celular , Movimento Celular , Humanos , Integrinas/química , Integrinas/genética , Integrinas/imunologia , Neoplasias/diagnóstico , Neoplasias/imunologia , Neoplasias/terapia , Pesquisa/tendências , Transdução de Sinais , Linfócitos T
9.
Chem Biol Interact ; 331: 109270, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32991862

RESUMO

Hyperuricosuria is associated with kidney stone disease, especially uric acid (UA) and calcium oxalate (CaOx) types. Nevertheless, detailed mechanisms of hyperuricosuria-induced kidney stone formation remained unclear. This study examined changes in cellular proteome and function of renal tubular cells after treatment with high-dose UA for 48-h. Quantitative proteomics using 2-DE followed by nanoLC-ESI-ETD MS/MS tandem mass spectrometry revealed significant changes in levels of 22 proteins in the UA-treated cells. These proteomic data could be confirmed by Western blotting. Functional assays revealed an increase in intracellular ATP level and enhancement of tissue repairing capability in the UA-treated cells. Interestingly, levels of HSP70 and HSP90 (the known receptors for CaOx crystals) were increased in apical membranes of the UA-treated cells. CaOx crystal-cell adhesion assay revealed significant increase in CaOx-binding capability of the UA-treated cells, whereas neutralization of the surface HSP70 and/or HSP90 using their specific monoclonal antibodies caused significant reduction in such binding capability. These findings highlighted changes in renal tubular cells in response to high-dose UA that may, at least in part, explain the pathogenic mechanisms of hyperuricosuria-induced mixed kidney stone disease.


Assuntos
Trifosfato de Adenosina/metabolismo , Oxalato de Cálcio/metabolismo , Proteoma/efeitos dos fármacos , Ácido Úrico/farmacologia , Animais , Anticorpos Monoclonais/imunologia , Oxalato de Cálcio/química , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cristalização , Cães , Proteínas de Choque Térmico HSP70/imunologia , Proteínas de Choque Térmico HSP70/metabolismo , Cálculos Renais/etiologia , Cálculos Renais/patologia , Células Madin Darby de Rim Canino/citologia , Células Madin Darby de Rim Canino/efeitos dos fármacos , Células Madin Darby de Rim Canino/metabolismo , Mapas de Interação de Proteínas , Proteoma/análise , Espectrometria de Massas em Tandem , Ácido Úrico/urina
10.
Anticancer Res ; 40(9): 5125-5140, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878801

RESUMO

BACKGROUND/AIM: Neuroblastoma (NB), the most common extracranial malignant childhood tumor accounts for about 15% of cancer-related deaths in children. Despite the intensive treatment of patients with high-risk scarification of NB, clinical outcomes indicate tumor recurrence greater than 50% and late severe adverse effects. Oxazolidinones are 5-membered heterocyclic compounds with antibacterial activity against resistant bacterial strains. Structural modifications around the oxazolidinone moiety have resulted in derivatives with anti-cancer properties against proliferation, motility, and invasion of breast cancer cells. This study aimed to examine the anti-cancer potential of novel oxazolidinones against a model of a neuroblastoma cell line. MATERIALS AND METHODS: Newly synthesized and characterized triazolyl-oxazolidinone derivatives were incubated with neuroblastoma Kelly cells. The anti-proliferation and anti-progression effects of the compounds were evaluated by MTT, and adhesion with migration assays. RESULTS: The 5-nitrofuroyl glycinyl-oxazolidinone containing 4-methyltriazolyl group demonstrated the most potent activity with an IC50=6.52 µM. Furthermore, the D-isomer of 5-nitrothiophenecarbonyl alaninyl containing derivative reduced the adhesion to fibronectin by 56.34%, while the D-isomer of 5-nitrofuroyl alaninyl derivative reduced the migration of Kelly cells by 29.14%. CONCLUSION: The presence of the 4-methyltriazolyl moiety seems to enhance the anti-proliferative property of triazolyl-oxazolidinone derivatives, as demonstrated by PH-145. There is little or no effect of the stereochemistry of the alanine side-chain on the antiproliferative effect, as demonstrated by the 5-nitrofuroyl D- and L-alaninyl containing derivatives with similar IC50 values. The observed differences in the inhibition of adhesion and migration by the oxazolidinones on Kelly cells provide a new therapeutic approach that needs further investigation.


Assuntos
Antineoplásicos/farmacologia , Oxazolidinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Neuroblastoma , Oxazolidinonas/síntese química , Oxazolidinonas/química
11.
Medicine (Baltimore) ; 99(39): e22172, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32991410

RESUMO

Osteoporosis is a severe chronic skeletal disorder that increases the risks of disability and mortality; however, the mechanism of this disease and the protein markers for prognosis of osteoporosis have not been well characterized. This study aims to characterize the imbalanced serum proteostasis, the disturbed pathways, and potential serum markers in osteoporosis by using a set of bioinformatic analyses. In the present study, the large-scale proteomics datasets (PXD006464) were adopted from the Proteome Xchange database and processed with MaxQuant. The differentially expressed serum proteins were identified. The biological process and molecular function were analyzed. The protein-protein interactions and subnetwork modules were constructed. The signaling pathways were enriched. We identified 209 upregulated and 230 downregulated serum proteins. The bioinformatic analyses revealed a highly overlapped functional protein classification and the gene ontology terms between the upregulated and downregulated protein groups. Protein-protein interactions and pathway analyses showed a high enrichment in protein synthesis, inflammation, and immune response in the upregulated proteins, and cell adhesion and cytoskeleton regulation in the downregulated proteins. Our findings greatly expand the current view of the roles of serum proteins in osteoporosis and shed light on the understanding of its underlying mechanisms and the discovery of serum proteins as potential markers for the prognosis of osteoporosis.


Assuntos
Mineração de Dados/métodos , Osteoporose/sangue , Proteoma/fisiologia , Biomarcadores , Adesão Celular/fisiologia , Biologia Computacional , Citoesqueleto/metabolismo , Regulação para Baixo , Humanos , Mediadores da Inflamação/metabolismo , Mapas de Interação de Proteínas/fisiologia , Proteômica , Regulação para Cima
12.
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
13.
Nat Commun ; 11(1): 4477, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901019

RESUMO

Individual cells detach from cohesive ensembles during development and can inappropriately separate in disease. Although much is known about how cells separate from epithelia, it remains unclear how cells disperse from clusters lacking apical-basal polarity, a hallmark of advanced epithelial cancers. Here, using live imaging of the developmental migration program of Drosophila primordial germ cells (PGCs), we show that cluster dispersal is accomplished by stabilizing and orienting migratory forces. PGCs utilize a G protein coupled receptor (GPCR), Tre1, to guide front-back migratory polarity radially from the cluster toward the endoderm. Posteriorly positioned myosin-dependent contractile forces pull on cell-cell contacts until cells release. Tre1 mutant cells migrate randomly with transient enrichment of the force machinery but fail to separate, indicating a temporal contractile force threshold for detachment. E-cadherin is retained on the cell surface during cell separation and augmenting cell-cell adhesion does not impede detachment. Notably, coordinated migration improves cluster dispersal efficiency by stabilizing cell-cell interfaces and facilitating symmetric pulling. We demonstrate that guidance of inherent migratory forces is sufficient to disperse cell clusters under physiological settings and present a paradigm for how such events could occur across development and disease.


Assuntos
Drosophila melanogaster/embriologia , Células Germinativas Embrionárias/fisiologia , Animais , Animais Geneticamente Modificados , Fenômenos Biomecânicos , Padronização Corporal/fisiologia , Caderinas/metabolismo , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Células Germinativas Embrionárias/citologia , Microscopia de Fluorescência por Excitação Multifotônica , Miosina Tipo II/metabolismo , Transdução de Sinais , Análise de Célula Única , Proteínas rho de Ligação ao GTP/metabolismo
14.
Science ; 369(6504): 618-619, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32764051
15.
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
16.
PLoS One ; 15(8): e0237116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857787

RESUMO

Bone metastases are a frequent complication in prostate cancer, and several studies have shown that vitamin D deficiency promotes bone metastases. However, while many studies focus on vitamin D's role in cell metabolism, the effect of chronically low vitamin D levels on bone tissue, i.e. insufficient mineralization of the tissue, has largely been ignored. To investigate, whether poor tissue mineralization promotes cancer cell attachment, we used a fluorescence based adhesion assay and single cell force spectroscopy to quantify the adhesion of two prostate cancer cell lines to well-mineralized and demineralized dentin, serving as biomimetic bone model system. Adhesion rates of bone metastases-derived PC3 cells increased significantly on demineralized dentin. Additionally, on mineralized dentin, PC3 cells adhered mainly via membrane anchored surface receptors, while on demineralized dentin, they adhered via cytoskeleton-anchored transmembrane receptors, pointing to an interaction via exposed collagen fibrils. The adhesion rate of lymph node derived LNCaP cells on the other hand is significantly lower than that of PC3 and not predominately mediated by cytoskeleton-linked receptors. This indicates that poor tissue mineralization facilitates the adhesion of invasive cancer cells by the exposure of collagen and emphasizes the disease modifying effect of sufficient vitamin D for cancer patients.


Assuntos
Calcificação Fisiológica , Adesão Celular , Neoplasias da Próstata/metabolismo , Animais , Materiais Biomiméticos/química , Linhagem Celular Tumoral , Colágeno/metabolismo , Citoesqueleto/metabolismo , Dentina/química , Elefantes , Humanos , Masculino , Receptores de Superfície Celular/metabolismo , Tecidos Suporte/química , Vitamina D/metabolismo
17.
Science ; 369(6504): 698-702, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32764072

RESUMO

Plant grafting is conducted for fruit and vegetable propagation, whereby a piece of living tissue is attached to another through cell-cell adhesion. However, graft compatibility limits combinations to closely related species, and the mechanism is poorly understood. We found that Nicotiana is capable of graft adhesion with a diverse range of angiosperms. Comparative transcriptomic analyses on graft combinations indicated that a subclade of ß-1,4-glucanases secreted into the extracellular region facilitates cell wall reconstruction near the graft interface. Grafting was promoted by overexpression of the ß-1,4-glucanase. Using Nicotiana stem as an interscion, we produced tomato fruits on rootstocks from other plant families. These findings demonstrate that the process of cell-cell adhesion is a potential target to enhance plant grafting techniques.


Assuntos
Adesão Celular/fisiologia , Comunicação Celular/fisiologia , Celulase/metabolismo , Horticultura/métodos , Proteínas de Plantas/metabolismo , Tabaco/fisiologia , Adesão Celular/genética , Comunicação Celular/genética , Celulase/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Tabaco/enzimologia , Tabaco/genética , Transcrição Genética
18.
Rinsho Ketsueki ; 61(7): 827-831, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32759571

RESUMO

Integrins play an important role in the homing, survival, proliferation, and drug resistance of multiple myeloma (MM) cells in the bone marrow. Among the many integrin families, the integrins α4ß1 (VLA-4) and α4ß7 have been reported to have important functions in MM cells. Previous studies have also reported that the three-dimensional structure of an integrin changes depending on its activation state; however, the conformations of integrins expressed in MM cells have not been studied so far. We recently observed that integrin α4ß7 constitutively adopts an active conformation in MM cells, and chimeric antigen receptor (CAR) T cell therapy that targets the activated conformation of integrin ß7 is a promising new treatment for MM. We are now clarifying the mechanism for the constitutive activation of integrin ß7 in MM and its relationship with the pathology of MM.


Assuntos
Mieloma Múltiplo , Medula Óssea , Adesão Celular , Humanos , Imunoterapia Adotiva , Integrina alfa4beta1 , Integrinas
19.
Nat Cell Biol ; 22(9): 1103-1115, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32839548

RESUMO

Plasticity of cancer invasion and metastasis depends on the ability of cancer cells to switch between collective and single-cell dissemination, controlled by cadherin-mediated cell-cell junctions. In clinical samples, E-cadherin-expressing and -deficient tumours both invade collectively and metastasize equally, implicating additional mechanisms controlling cell-cell cooperation and individualization. Here, using spatially defined organotypic culture, intravital microscopy of mammary tumours in mice and in silico modelling, we identify cell density regulation by three-dimensional tissue boundaries to physically control collective movement irrespective of the composition and stability of cell-cell junctions. Deregulation of adherens junctions by downregulation of E-cadherin and p120-catenin resulted in a transition from coordinated to uncoordinated collective movement along extracellular boundaries, whereas single-cell escape depended on locally free tissue space. These results indicate that cadherins and extracellular matrix confinement cooperate to determine unjamming transitions and stepwise epithelial fluidization towards, ultimately, cell individualization.


Assuntos
Neoplasias da Mama/patologia , Adesão Celular/fisiologia , Invasividade Neoplásica/patologia , Junções Aderentes/patologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Regulação para Baixo/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Células HEK293 , Humanos , Junções Intercelulares/patologia , Células MCF-7 , Camundongos Endogâmicos BALB C
20.
Proc Natl Acad Sci U S A ; 117(36): 22423-22429, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848073

RESUMO

Metastases are the cause of the vast majority of cancer deaths. In the metastatic process, cells migrate to the vasculature, intravasate, extravasate, and establish metastatic colonies. This pattern of spread requires the cancer cells to change shape and to navigate tissue barriers. Approaches that block this mechanical program represent new therapeutic avenues. We show that 4-hydroxyacetophenone (4-HAP) inhibits colon cancer cell adhesion, invasion, and migration in vitro and reduces the metastatic burden in an in vivo model of colon cancer metastasis to the liver. Treatment with 4-HAP activates nonmuscle myosin-2C (NM2C) (MYH14) to alter actin organization, inhibiting the mechanical program of metastasis. We identify NM2C as a specific therapeutic target. Pharmacological control of myosin isoforms is a promising approach to address metastatic disease, one that may be readily combined with other therapeutic strategies.


Assuntos
Acetofenonas/farmacologia , Actomiosina/metabolismo , Citoesqueleto , Metástase Neoplásica/fisiopatologia , Actinas/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Feminino , Células HCT116 , Humanos , Camundongos , Camundongos Nus
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