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1.
ACS Appl Mater Interfaces ; 16(37): 49013-49029, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39231128

RESUMO

Heparan sulfate (HS) is a major component of cell surface glycocalyx with extensive negative charges and plays a protective role by preventing toxins, including small molecule drugs and anticancer cationic lytic peptides (ACLPs), from cells. However, this effect may compromise the treatment efficiency of anticancer drugs. To overcome the impedance of cancer cell glycocalyx, an HS-targeting ACLP PTP-7z was designed by fusion of an ACLP and a Zn2+-binding HS-targeting peptide. Upon Zn2+ ion binding, PTP-7z could self-assemble into uniform nanoparticles and show improved serum stability and reduced hemolysis, which enable it to self-deliver to tumor sites. The peptide PTP-7z showed a pH- and Zn2+ ion-dependent HS-binding ability, which triggers the HS-induced in situ self-assembling on the cancer cell surface in the acidic tumor microenvironment (TME). The self-assembled PTP-7z can overcome the impedance of cell glycocalyx by either disrupting cell membranes or translocating into cells through endocytosis and inducing cell apoptosis. Moreover, PTP-7z can also inhibit cancer cell migration. These results proved that HS-responsive in situ self-assembling is a practical strategy to overcome the cancer cell glycocalyx barrier for ACLPs and could be extended to the design of other peptide drugs to promote their in vivo application.


Assuntos
Antineoplásicos , Glicocálix , Heparitina Sulfato , Peptídeos , Heparitina Sulfato/química , Heparitina Sulfato/farmacologia , Glicocálix/metabolismo , Glicocálix/química , Humanos , Peptídeos/química , Peptídeos/farmacologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Camundongos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Nanopartículas/química
2.
ACS Nano ; 18(32): 21512-21522, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39096486

RESUMO

Although minimally invasive interventional occluders can effectively seal heart defect tissue, they still have some limitations, including poor endothelial healing, intense inflammatory response, and thrombosis formation. Herein, a polyphenol-reinforced medicine/peptide glycocalyx-like coating was prepared on cardiac occluders. A coating consisting of carboxylated chitosan, epigallocatechin-3-gallate (EGCG), tanshinone IIA sulfonic sodium (TSS), and hyaluronic acid grafted with 3-aminophenylboronic acid was prepared. Subsequently, the mercaptopropionic acid-GGGGG-Arg-Glu-Asp-Val peptide was grafted by the thiol-ene "click" reaction. The coating showed good hydrophilicity and free radical-scavenging ability and could release EGCG-TSS. The results of biological experiments suggested that the coating could reduce thrombosis by promoting endothelialization, and promote myocardial repair by regulating the inflammatory response. The functions of regulating cardiomyocyte apoptosis and metabolism were confirmed, and the inflammatory regulatory functions of the coating were mainly dependent on the NF-kappa B and TNF signaling pathway.


Assuntos
Glicocálix , Hidrogéis , Polifenóis , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Polifenóis/química , Polifenóis/farmacologia , Glicocálix/metabolismo , Glicocálix/química , Glicocálix/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ratos , Apoptose/efeitos dos fármacos , Camundongos , Miocárdio/metabolismo , Catequina/química , Catequina/análogos & derivados , Catequina/farmacologia , Ratos Sprague-Dawley , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Masculino
3.
Chembiochem ; 24(6): e202200707, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36642971

RESUMO

A heavy layer of glycans forms a brush matrix bound to the outside of all the cells in our bodies; it is referred to as the "sugar forest" or glycocalyx. Beyond the increased appreciation of the glycocalyx over the past two decades, recent advances in engineering the glycocalyx on live cells have spurred the creation of cellular drugs and novel medical treatments. The development of new tools and techniques has empowered scientists to manipulate the structures and functions of cell-surface glycans on target cells and endow target cells with desired properties. Herein, we provide an overview of live-cell glycocalyx engineering strategies for controlling the cell-surface molecular repertory to suit therapeutic applications, even though the realm of this field remains young and largely unexplored.


Assuntos
Glicocálix , Polissacarídeos , Glicocálix/química , Glicocálix/metabolismo , Membrana Celular/metabolismo , Polissacarídeos/química
4.
Colloids Surf B Biointerfaces ; 212: 112337, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35051794

RESUMO

The endothelial glycocalyx is a carbohydrate-rich layer overlying the outermost surface of endothelial cells. It mediates intercellular interactions by specific chemical compositions (e.g., proteoglycans containing glycosaminoglycan (GAG) side chains) and micro/nanotopography. Inspired by the endothelial glycocalyx, we fabricated a series of glycocalyx-mimetic surfaces with tunable chemical compositions (GAG-like polymers with different functional units) and topographical structures (micro/nanopatterns with pillars different in size). The combination of micro/nanopatterns and GAG-like polymers was flexibly and precisely controlled by replica molding using silicon templates (Si templates) and visible light-initiated polymerization. Human umbilical vein endothelial cells (HUVECs) and human umbilical vein smooth muscle cells (HUVSMCs) were suppressed on surfaces modified with polymers of 2-methacrylamido glucopyranose (MAG) but promoted on surfaces modified with polymers of sodium 4-vinyl-benzenesulfonate (SS) and copolymers of SS and MAG. Surface micro/nanopatterns showed highly complicated effects on surfaces grafted with different GAG-like polymers. Moreover, the spread of HUVSMCs was highly promoted on all flat/patterned surfaces containing sulfonate units, and the elongation effect was stronger on surfaces with smaller pillars. On all the flat/patterned surfaces modified with GAG-like polymers, the adsorption of human vascular endothelial growth factor (VEGF) and human basic fibroblast growth factor (bFGF) was improved, and the amount of VEGF and bFGF absorbed on patterned surfaces containing sulfonate units decreased with pattern dimensions. The decreasing trend of VEGF and bFGF adsorption was in accordance with HUVEC density, suggesting that glycocalyx-mimetic surfaces influence the adsorption of VEGF and bFGF and further influence the growth behavior of vascular cells.


Assuntos
Glicocálix , Fator A de Crescimento do Endotélio Vascular , Adsorção , Células Cultivadas , Glicocálix/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Propriedades de Superfície
5.
J Biol Chem ; 297(6): 101391, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34762909

RESUMO

Placental malaria infection is mediated by the binding of the malarial VAR2CSA protein to the placental glycosaminoglycan, chondroitin sulfate. Recombinant subfragments of VAR2CSA (rVAR2) have also been shown to bind specifically and with high affinity to cancer cells and tissues, suggesting the presence of a shared type of oncofetal chondroitin sulfate (ofCS) in the placenta and in tumors. However, the exact structure of ofCS and what determines the selective tropism of VAR2CSA remains poorly understood. In this study, ofCS was purified by affinity chromatography using rVAR2 and subjected to detailed structural analysis. We found high levels of N-acetylgalactosamine 4-O-sulfation (∼80-85%) in placenta- and tumor-derived ofCS. This level of 4-O-sulfation was also found in other tissues that do not support parasite sequestration, suggesting that VAR2CSA tropism is not exclusively determined by placenta- and tumor-specific sulfation. Here, we show that both placenta and tumors contain significantly more chondroitin sulfate moieties of higher molecular weight than other tissues. In line with this, CHPF and CHPF2, which encode proteins required for chondroitin polymerization, are significantly upregulated in most cancer types. CRISPR/Cas9 targeting of CHPF and CHPF2 in tumor cells reduced the average molecular weight of cell-surface chondroitin sulfate and resulted in a marked reduction of rVAR2 binding. Finally, utilizing a cell-based glycocalyx model, we showed that rVAR2 binding correlates with the length of the chondroitin sulfate chains in the cellular glycocalyx. These data demonstrate that the total amount and cellular accessibility of chondroitin sulfate chains impact rVAR2 binding and thus malaria infection.


Assuntos
Antígenos de Protozoários/metabolismo , Sulfatos de Condroitina/metabolismo , Glicocálix/metabolismo , Malária Falciparum/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Antígenos de Protozoários/química , Antígenos de Protozoários/genética , Sulfatos de Condroitina/química , Sulfatos de Condroitina/genética , Feminino , Glicocálix/química , Glicocálix/genética , Células HEK293 , Células HeLa , Humanos , Malária Falciparum/genética , N-Acetilgalactosaminiltransferases/genética , N-Acetilgalactosaminiltransferases/metabolismo , Placenta/metabolismo , Plasmodium falciparum/genética , Gravidez , Proteínas de Protozoários/química , Proteínas de Protozoários/genética
6.
Int J Mol Sci ; 22(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34830227

RESUMO

Ricin toxin isolated from the castor bean (Ricinus communis) is one of the most potent and lethal molecules known. While the pathophysiology and clinical consequences of ricin poisoning by the parenteral route, i.e., intramuscular penetration, have been described recently in various animal models, the preceding mechanism underlying the clinical manifestations of systemic ricin poisoning has not been completely defined. Here, we show that following intramuscular administration, ricin bound preferentially to the vasculature in both mice and swine, leading to coagulopathy and widespread hemorrhages. Increased levels of circulating VEGF and decreased expression of vascular VE-cadherin caused blood vessel impairment, thereby promoting hyperpermeability in various organs. Elevated levels of soluble heparan sulfate, hyaluronic acid and syndecan-1 were measured in blood samples following ricin intoxication, indicating that the vascular glycocalyx of both mice and swine underwent extensive damage. Finally, by using side-stream dark field intravital microscopy imaging, we determined that ricin poisoning leads to microvasculature malfunctioning, as manifested by aberrant blood flow and a significant decrease in the number of diffused microvessels. These findings, which suggest that glycocalyx shedding and microcirculation dysfunction play a major role in the pathology of systemic ricin poisoning, may serve for the formulation of specifically tailored therapies for treating parenteral ricin intoxication.


Assuntos
Células Endoteliais/efeitos dos fármacos , Glicocálix/efeitos dos fármacos , Ricina/toxicidade , Ricinus/química , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Relação Dose-Resposta a Droga , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Glicocálix/química , Glicocálix/metabolismo , Heparitina Sulfato/química , Heparitina Sulfato/metabolismo , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/metabolismo , Hidrólise , Injeções Intramusculares , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Microcirculação/efeitos dos fármacos , Ricina/isolamento & purificação , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/patologia , Suínos , Sindecana-1/química , Sindecana-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Annu Rev Cell Dev Biol ; 37: 257-283, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34613816

RESUMO

Morphological transitions are typically attributed to the actions of proteins and lipids. Largely overlooked in membrane shape regulation is the glycocalyx, a pericellular membrane coat that resides on all cells in the human body. Comprised of complex sugar polymers known as glycans as well as glycosylated lipids and proteins, the glycocalyx is ideally positioned to impart forces on the plasma membrane. Large, unstructured polysaccharides and glycoproteins in the glycocalyx can generate crowding pressures strong enough to induce membrane curvature. Stress may also originate from glycan chains that convey curvature preference on asymmetrically distributed lipids, which are exploited by binding factors and infectious agents to induce morphological changes. Through such forces, the glycocalyx can have profound effects on the biogenesis of functional cell surface structures as well as the secretion of extracellular vesicles. In this review, we discuss recent evidence and examples of these mechanisms in normal health and disease.


Assuntos
Glicocálix , Membrana Celular/metabolismo , Glicocálix/química , Glicocálix/metabolismo , Glicoproteínas , Humanos , Polissacarídeos/análise , Polissacarídeos/química , Polissacarídeos/metabolismo
8.
Int J Mol Sci ; 22(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070901

RESUMO

Glycosaminoglycans (GAGs) and proteoglycans (PGs) are major components of the glycocalyx. The secreted GAG and CD44 ligand hyaluronic acid (HA), and the cell surface PG syndecan-1 (Sdc-1) modulate the expression and activity of cytokines, chemokines, growth factors, and adhesion molecules, acting as critical regulators of tumor cell behavior. Here, we studied the effect of Sdc-1 siRNA depletion and HA treatment on hallmark processes of cancer in breast cancer cell lines of different levels of aggressiveness. We analyzed HA synthesis, and parameters relevant to tumor progression, including the stem cell phenotype, Wnt signaling constituents, cell cycle progression and apoptosis, and angiogenic markers in luminal MCF-7 and triple-negative MDA-MB-231 cells. Sdc-1 knockdown enhanced HAS-2 synthesis and HA binding in MCF-7, but not in MDA-MB-231 cells. Sdc-1-depleted MDA-MB-231 cells showed a reduced CD24-/CD44+ population. Furthermore, Sdc-1 depletion was associated with survival signals in both cell lines, affecting cell cycle progression and apoptosis evasion. These changes were linked to the altered expression of KLF4, MSI2, and miR-10b and differential changes in Erk, Akt, and PTEN signaling. We conclude that Sdc-1 knockdown differentially affects HA metabolism in luminal and triple-negative breast cancer model cell lines and impacts the stem phenotype, cell survival, and angiogenic factors.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glicocálix/metabolismo , Ácido Hialurônico/metabolismo , Sindecana-1/genética , Neoplasias de Mama Triplo Negativas/genética , Via de Sinalização Wnt/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Antígeno CD24/genética , Antígeno CD24/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Bases de Dados Factuais , Feminino , Glicocálix/química , Glicocálix/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Hialuronan Sintases/genética , Hialuronan Sintases/metabolismo , Ácido Hialurônico/farmacologia , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Células MCF-7 , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Análise de Sobrevida , Sindecana-1/antagonistas & inibidores , Sindecana-1/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
9.
Reprod Biol Endocrinol ; 19(1): 73, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33992099

RESUMO

BACKGROUND: Low endometrial receptivity is one of the major factors affecting successful implantation in assisted reproductive technologies (ART). Infertile patients with thin endometrium have a significantly lower cumulative clinical pregnancy rate than patients with normal endometrium. Molecular pathophysiology of low receptivity of thin endometrium remains understudied. We have investigated composition of glycocalyx of the apical surface of luminal and glandular epithelial cells in thin endometrium of infertile women. METHODS: Thirty-two patients with tubal-peritoneal infertility undergoing in vitro fertilization (IVF) were included in the study. Endometrial samples were obtained in a natural menstrual cycle. Patients were divided into two groups: patients with normal endometrium (≥8 mm) and with thin endometrium (< 8 mm). Histochemical and immunohistochemical analysis of paraffin-embedded endometrial samples was performed using six biotinylated lectins (UEA-I, MAL-II, SNA, VVL, ECL, Con A) and anti-LeY and MECA-79 monoclonal antibodies (MAbs). RESULTS: Complex glycans analysis taking into account the adjusted specificity of glycan-binding MAbs revealed 1.3 times less expression of MECA-79 glycans on the apical surface of the luminal epithelial cells of thin endometrium compared to normal endometrium; this deficiency may adversely affect implantation, since MECA-79 glycans are a ligand of L-selectin and mediate intercellular interactions. The glycans containing a type-2 unit Galß1-4GlcNAcß (LacNAc) but lacking sulfo-residues at 6-OH of GlcNAcß, and binding to MECA-79 MAbs were found; they can be considered as potential markers of endometrium receptivity. Expression of the lectins-stained glycans on the apical surfaces of the luminal and glandular epithelial cells did not differ significantly. Correlation between the expression of difucosylated oligosaccharide LeY on the apical surfaces of the luminal and glandular epithelial cells was found in patients with thin endometrium and recurrent implantation failure. A similar relationship was shown for mannose-rich glycans. CONCLUSIONS: Specific features of key glycans expression in epithelial compartments of thin endometrium may be essential for morphogenesis of the endometrial functional layer and explain its low receptivity.


Assuntos
Endométrio/patologia , Células Epiteliais/metabolismo , Glicocálix/química , Infertilidade Feminina/metabolismo , Polissacarídeos/análise , Adulto , Anticorpos Monoclonais/imunologia , Sequência de Carboidratos , Polaridade Celular , Implantação do Embrião , Transferência Embrionária , Células Epiteliais/ultraestrutura , Feminino , Fertilização in vitro , Glicosilação , Humanos , Infertilidade Feminina/patologia , Análise em Microsséries , Morfogênese , Projetos Piloto , Polissacarídeos/imunologia
10.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33802220

RESUMO

Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac4ManNAz) and N-alkyneacetylmannosamine (Ac4ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac4ManNAz was detectable for up to six days while Ac4ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.


Assuntos
Glicocálix , Hexosaminas , Células-Tronco Mesenquimais/metabolismo , Engenharia Metabólica , Modelos Biológicos , Mioblastos Esqueléticos/metabolismo , Linhagem Celular Transformada , Glicocálix/química , Glicocálix/metabolismo , Hexosaminas/química , Hexosaminas/metabolismo , Humanos
11.
Proc Natl Acad Sci U S A ; 117(23): 12643-12650, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32457151

RESUMO

The mechanism(s) by which cell-tethered mucins modulate infection by influenza A viruses (IAVs) remain an open question. Mucins form both a protective barrier that can block virus binding and recruit IAVs to bind cells via the sialic acids of cell-tethered mucins. To elucidate the molecular role of mucins in flu pathogenesis, we constructed a synthetic glycocalyx to investigate membrane-tethered mucins in the context of IAV binding and fusion. We designed and synthesized lipid-tethered glycopolypeptide mimics of mucins and added them to lipid bilayers, allowing chemical control of length, glycosylation, and surface density of a model glycocalyx. We observed that the mucin mimics undergo a conformational change at high surface densities from a compact to an extended architecture. At high surface densities, asialo mucin mimics inhibited IAV binding to underlying glycolipid receptors, and this density correlated to the mucin mimic's conformational transition. Using a single virus fusion assay, we observed that while fusion of virions bound to vesicles coated with sialylated mucin mimics was possible, the kinetics of fusion was slowed in a mucin density-dependent manner. These data provide a molecular model for a protective mechanism by mucins in IAV infection, and therefore this synthetic glycocalyx provides a useful reductionist model for studying the complex interface of host-pathogen interactions.


Assuntos
Glicocálix/virologia , Vírus da Influenza A/fisiologia , Bicamadas Lipídicas/química , Mucinas/metabolismo , Internalização do Vírus , Glicocálix/química , Mucinas/química , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Conformação Proteica
12.
Small ; 16(27): e1906890, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32068952

RESUMO

Akin to a cellular "fingerprint," the glycocalyx is a glycan-enriched cellular coating that plays a crucial role in mediating cell-to-cell interactions. To gain a better understanding of the factors that govern in vivo recognition, artificial glycoproteins were initially created to probe changes made to the accumulation and biodistribution of specific glycan assemblies through biomimicry. As a result, the organ-specific accumulation for a variety of glycoproteins decorated with simple and/or complex glycans was identified. Additionally, binding trends with regard to cancer cell selectivity were also investigated. To exploit the knowledge gained from these studies, numerous groups thus became engaged in developing targeted drug methodologies based on the use of artificial glycoproteins. This has either been done through adopting the glycoprotein scaffold as a drug carrier, or to directly glycosylate therapeutic proteins/enzymes to localize their biological activity. The principle aim of this Review is to present the foundational research that has driven artificial glycoprotein-based targeting and subsequent adaptations with potential therapeutic applications.


Assuntos
Sistemas de Liberação de Medicamentos , Glicoproteínas , Sistemas de Liberação de Medicamentos/métodos , Glicocálix/química , Glicocálix/metabolismo , Glicoproteínas/química , Humanos , Neoplasias/tratamento farmacológico , Distribuição Tecidual
13.
Faraday Discuss ; 219(0): 168-182, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31305856

RESUMO

The glycocalyx is the immediate pericellular matrix that surrounds many cell types, including endothelial cells (ECs), and is typically composed of glycans (glycosaminoglycans, proteoglycans, and glycoproteins). The endothelial glycocalyx is rich in hyaluronic acid (HA), which plays an important role in the maintenance of vascular integrity, although fundamental questions about the precise molecular regulation mechanisms remain unanswered. Here, we investigate the contribution of HA to the regulation of endothelial function using model surfaces. The peptide sequence GAHWQFNALTVR, previously identified by phage display with strong binding affinity for HA and named Pep-1, was thiolated at the N-terminal to form self-assembled monolayers (SAMs) on gold (Au) substrates, and microcontact printing (µCP) was used to develop patterned surfaces for the controlled spatial presentation of HA. Acetylated Pep-1 and a scrambled sequence of Pep-1 were used as controls. The SAMs and HA-coated surfaces were characterized by X-ray photoelectron spectroscopy (XPS), contact angle measurements, and quartz crystal microbalance with dissipation (QCM-D) monitoring, which confirmed the binding and presence of thiolated peptides on the Au surfaces and the deposition of HA. Fluorescence microscopy showed the localization of fluorescently labelled HA only on areas printed with Pep-1 SAMs. Cell culture studies demonstrated that low molecular weight HA improved the adhesion of human umbilical vein endothelial cells (HUVECs) to the substrate and also stimulated their migration. This research provides insight into the use of SAMs for the controlled presentation of HA with defined size in cultures of HUVECs to study their functions.


Assuntos
Materiais Biocompatíveis/química , Células Endoteliais/química , Glicocálix/química , Ácido Hialurônico/química , Bioimpressão , Adesão Celular , Movimento Celular , Células Endoteliais/citologia , Ouro/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Peptídeos/química , Compostos de Sulfidrila/química , Propriedades de Superfície
14.
Faraday Discuss ; 219(0): 138-153, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31313786

RESUMO

In the mucosal epithelium, the cellular glycocalyx can project tens to hundreds of nanometers into the extracellular space, erecting a physical barrier that provides protective functions, mediates the exchange of nutrients and regulates cellular interactions. Little is understood about how the physical properties of the mucosal glycocalyx influence molecular recognition at the cellular boundary. Here, we report the synthesis of PEG-based glycopolymers with tunable glycan composition, which approximate the extended architecture of mucin glycoproteins, and tether them to the plasma membranes of red blood cells (RBC) to construct an artificial mucin brush-like glycocalyx. We evaluated the association of two lectins, ConA and SNA, with their endogenous glycan ligands on the surface of the remodelled cells. The extended glycocalyx provided protection against agglutination of RBCs by both lectins; however, the rate and magnitude of ConA binding were attenuated to a greater degree in the presence of the glycopolymer spectators compared to those measured for SNA. The different sensitivity of ConA and SNA to glycocalyx crowding likely arises from the distinct presentation of their mannoside and sialoside receptors, respectively, within the native RBC glycocalyx.


Assuntos
Materiais Biomiméticos/metabolismo , Eritrócitos/metabolismo , Glicocálix/metabolismo , Hemaglutinação , Polietilenoglicóis/metabolismo , Materiais Biomiméticos/química , Concanavalina A/metabolismo , Membrana Eritrocítica/química , Membrana Eritrocítica/metabolismo , Eritrócitos/citologia , Glicocálix/química , Glicoconjugados/química , Glicoconjugados/metabolismo , Humanos , Mucinas/química , Mucinas/metabolismo , Lectinas de Plantas/metabolismo , Polietilenoglicóis/química , Polímeros/química , Polímeros/metabolismo , Proteínas Inativadoras de Ribossomos/metabolismo , Sambucus nigra/metabolismo
15.
Adv Exp Med Biol ; 1097: 29-49, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30315538

RESUMO

There has been rapid progress over the past decade to extend the concept that a quasiperiodic inner endothelial glycocalyx layer (EGL, <300 nm thick, with key components associated with the endothelial cell membrane) forms the primary molecular filter between circulating blood and the body tissues. The EGL is common to both continuous and fenestrated microvessels. The revised Starling Principle describing steady-state fluid exchange across the EGL describes new ways to understand transvascular exchange of water and plasma proteins in microvessels in both normal and disturbed states such as hemorrhage and fluid replacement during surgery. At the same time, direct optical observations describe endothelial surface layers (ESLs) with porous outer layers that extend 1-2 µm beyond the EGL. Preliminary analyses of water and plasma protein transport through barriers formed by a thick ESL in series with the EGL indicate that such two-layer structures can have permeability properties that are not consistent with measured water and plasma exchange in microvessels. Such multilayer models provide a basis for future detailed evaluations of both transports across endothelial surface layers and the methods to image components of both the EGL and the ESL. Furthermore changes in the thickness and distribution of thick ESLs in vessels with diameters larger than 50 µm may not reflect functional changes in the inner glycocalyx layer.


Assuntos
Endotélio Vascular , Glicocálix/química , Proteínas Sanguíneas , Células Endoteliais , Humanos , Modelos Moleculares , Estrutura Molecular
16.
Matrix Biol ; 74: 21-34, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29730504

RESUMO

Myocardial damage as a consequence of cardiotropic viruses leads to a broad variety of clinical presentations and is still a complicated condition to diagnose and treat. Whereas the extracellular matrix protein Secreted Protein Acidic and Rich in Cysteine or SPARC has been implicated in hypertensive and ischemic heart disease by modulating collagen production and cross-linking, its role in cardiac inflammation and endothelial function is yet unknown. Absence of SPARC in mice resulted in increased cardiac inflammation and mortality, and reduced cardiac systolic function upon coxsackievirus-B3 induced myocarditis. Intra-vital microscopic imaging of the microvasculature of the cremaster muscle combined with electron microscopic imaging of the microvasculature of the cardiac muscle uncovered the significance of SPARC in maintaining endothelial glycocalyx integrity and subsequent barrier properties to stop inflammation. Moreover, systemic administration of recombinant SPARC restored the endothelial glycocalyx and consequently reversed the increase in inflammation and mortality observed in SPARC KO mice in response to viral exposure. Reducing the glycocalyx in vivo by systemic administration of hyaluronidase, an enzyme that degrades the endothelial glycocalyx, mimicked the barrier defects found in SPARC KO mice, which could be restored by subsequent administration of recombinant SPARC. In conclusion, the secreted glycoprotein SPARC protects against adverse cardiac inflammation and mortality by improving the glycocalyx function and resulting endothelial barrier function during viral myocarditis.


Assuntos
Infecções por Coxsackievirus/metabolismo , Hialuronoglucosaminidase/farmacologia , Miocardite/virologia , Osteonectina/genética , Osteonectina/metabolismo , Músculos Abdominais/irrigação sanguínea , Músculos Abdominais/virologia , Animais , Infecções por Coxsackievirus/genética , Modelos Animais de Doenças , Enterovirus Humano B/patogenicidade , Técnicas de Inativação de Genes , Glicocálix/química , Masculino , Camundongos , Microscopia Eletrônica , Miocardite/genética , Miocardite/metabolismo
17.
Biomacromolecules ; 19(6): 2098-2108, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29634251

RESUMO

Immune checkpoint blockade by anti-PD-L1 monoclonal antibody (αPD-L1) has achieved unprecedented clinical benefits in certain cancers, whereas the therapeutic efficacy is often hindered by immunosuppressive tumor microenvironment mediated by tumor-associated macrophages (TAMs), which leads to innate resistance to this approach. To improve checkpoint blockade efficacy, the amphiphilic diblock copolymers poly(mannopyranoside/galactopyranoside methacrylate)- block-polystyrene are prepared by RAFT polymerization, which are sequentially self-assembled into glycocalyx-mimicking nanoparticles (GNPs) to neutralize TAMs. It is shown that GNPs can be specifically internalized by TAMs via lectin receptors, which results in upregulation of immunostimulatory IL-12 and downregulation of immunosuppressive IL-10, arginase 1, and CCL22, indicating functional reversion of protumor TAMs toward antitumor phenotype. The reversion of TAMs is proved to be mainly controlled by suppressing STAT6 and activating NF-κB phosphorylation. In vivo therapeutic studies have demonstrated that GNPs significantly enhance the therapeutic efficacy of αPD-L1 cancer therapy by reduction of tumor burden. Moreover, combination therapies with GNPs and αPD-L1 greatly improve immunosuppressive tumor microenvironment by reciprocal modulation of tumor-infiltrating effector and regulatory T cells. Notably, for the first time, our results demonstrate the reversion of TAMs and improvement of αPD-L1 cancer therapy by synthetic carbohydrate-containing nanomaterials. This research highlights a promising strategy for optimizing immune checkpoint blockade in cancer immunotherapy.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Glicocálix/química , Imunoterapia/métodos , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Animais , Antineoplásicos Imunológicos/química , Antineoplásicos Imunológicos/farmacocinética , Antígeno B7-H1/imunologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ativação Linfocitária/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Mimetismo Molecular , NF-kappa B/metabolismo , Nanopartículas/administração & dosagem , Nanopartículas/uso terapêutico , Polimerização , Polímeros/química , Polímeros/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Thromb Haemost ; 118(4): 676-687, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618154

RESUMO

Decrease of plasma activity of ADAMTS13, a metalloenzyme that cleaves von Willebrand factor (VWF) and prevents adhesion and aggregation of platelets, has been reported early after onset of systemic inflammation resulting from infections and after severe trauma. Here, we determined whether trauma-induced systemic (sterile) inflammation would be associated with a reduction of plasma ADAMTS13 activity in paediatric patients and its association with disease severity and outcome. Paediatric patients (n = 106) with severe trauma at a level 1 paediatric trauma centre between 2014 and 2016 were prospectively enrolled. Blood samples were collected upon arrival and at 24 hours and analysed for plasma levels of ADAMTS13 activity, VWF antigen, collagen binding activity, human neutrophil peptides (HNP) 1-3, coagulation abnormalities, endothelial glycocalyx damage and clinical outcome. Plasma samples were also collected for similar measurements from 52 healthy paediatric controls who underwent elective minor surgery. The median age of patients was 9 years with 81% sustaining blunt trauma. The median injury severity score was 22 and the mortality rate was 11%. Plasma levels of ADAMTS13 activity were significantly lower and plasma levels of VWF antigen and HNP 1-3 proteins were significantly higher for paediatric trauma patients on admission and at 24 hours when compared with controls. Finally, the lowest plasma ADAMTS13 activity was found in patients who died from their injuries. We conclude that relative plasma deficiency of ADAMTS13 activity may be associated with more severe traumatic injury, significant endothelial glycocalyx damage, coagulation abnormalities and mortality after severe trauma in paediatric patients.


Assuntos
Proteína ADAMTS13/sangue , Transtornos da Coagulação Sanguínea/complicações , Coagulação Sanguínea , Células Endoteliais/metabolismo , Ferimentos e Lesões/complicações , Adolescente , Testes de Coagulação Sanguínea , Plaquetas/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Colágeno/química , Feminino , Glicocálix/química , Humanos , Lactente , Inflamação , Masculino , Plasma/metabolismo , Estudos Prospectivos , Índice de Gravidade de Doença , Sindecana-1/sangue , Resultado do Tratamento , alfa-Defensinas/sangue , Fator de von Willebrand/análise
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 198: 338-345, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29486925

RESUMO

Combined micro-Raman imaging and AFM imaging are efficient methods for analyzing human tissue due to their high spatial and spectral resolution as well as sensitivity to subtle chemical, structural and topographical changes. The aim of this study was to determine biochemical composition and mechanical topography around blood vessels in the tumor mass of human breast tissue. Significant alterations of the chemical composition and structural architecture around the blood vessel were found compared to the normal breast tissue. A pronounced increase of collagen-fibroblast-glycocalyx network, as well as enhanced lactic acid, and glycogen activity in patients affected by breast cancer were reported.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Neovascularização Patológica/diagnóstico por imagem , Análise Espectral Raman/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Colágeno Tipo I/análise , Colágeno Tipo III/análise , Feminino , Glicocálix/química , Humanos , Microscopia de Força Atômica
20.
Cytometry A ; 93(1): 73-81, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28906588

RESUMO

The use of bone marrow-derived mesenchymal stem cells (MSCs) for clinical and experimental studies is increasing, but full characterization of MSCs in veterinary species is hindered by the variability in species-specific cell surface marker expression and antibody cross reactivity. Recent studies demonstrated that the glycans in the glycocalyx of MSCs are promising candidates as cell biomarkers. In the present study, we analyzed the glycocalyx of canine MSCs (cMSCs), ovine MSCs (oMSCs), and equine MSCs (eMSCs) using a cell microarray procedure in which MSCs were spotted on microarray slides and incubated with a panel of 14 biotinylated lectins and Cy3-conjugated streptavidin. The signal intensity was then detected using a microarray scanner. The lectin-binding signals indicated that the MSC surface of the investigated species contained both N- and O-linked glycan types, with N-glycosylation predominating over O-glycosylation and fucosylation being more abundant than sialylation. Relative quantification revealed an interspecific difference between these glycans. In addition, cMSCs expressed more α2,3-linked sialic acid (MAL II), terminal lactosamine (RCA120 ), and α1,6 and α1,3 fucosylated oligosaccharides (PSA, LTA); oMSCs exhibited more T antigen (Jacalin), GalNAcα1,3(LFucα1,2)Galß1,3/4GlcNAcß1 (DBA), chitotriose (succinylated WGA), and α1,2-linked fucose (UEA I); and eMSCs showed a higher density of α2,6 sialic acids (SNA) and high mannose N-glycans (Con A). Using cell microarray methodology, we have for the first time demonstrated differences in the glycosylation profiles of cMSC, oMSC, and eMSC surfaces. These results could be valuable as resources and references for MSC differentiation and molecular remodeling in clinical cell-based therapy and tissue engineering studies. © 2017 International Society for Advancement of Cytometry.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Polissacarídeos/metabolismo , Animais , Biomarcadores/metabolismo , Cães , Glicocálix/química , Glicocálix/metabolismo , Glicômica/métodos , Histocitoquímica , Cavalos , Lectinas/metabolismo , Células-Tronco Mesenquimais/citologia , Polissacarídeos/química , Ovinos , Especificidade da Espécie , Análise Serial de Tecidos/métodos
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