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1.
Food Chem ; 329: 127224, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516716

RESUMO

To overcome the drawbacks of antibody labeling dependence and single-readout system in the conventional lateral flow immunoassays (LFIAs) as well as the non-targeted combination of new capture agents reported recently for pathogen detection, in this work, a multi-readout and label-free LFIA was proposed for rapid detection of Escherichia coli O157:H7 (E. coli O157:H7) based on a nanozyme-bacteria-antibody sandwich pattern. A type of functional nanozyme-mannose modified Prussian blue (man-PB), was introduced as the recognition agent as well as signal indicator. Apart from original signal intensity on the T-line, the peroxidase-like catalytic activity-driven generation of colorimetric signal could be used as another format of quantitation. Importantly, such LFIA could exhibit excellent performance for target pathogens detection separately with a quantitative range of 102-108 cfu·mL-1 and a low detection limit of 102 cfu·mL-1 based on different readout formats, indicating the application potential of the proposed LFIA in real samples.


Assuntos
Escherichia coli O157/isolamento & purificação , Imunoensaio , Nanopartículas/química , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/imunologia , Catálise , Colorimetria , Escherichia coli O157/imunologia , Ferrocianetos/química , Microbiologia de Alimentos , Limite de Detecção , Manose/química , Nanopartículas/metabolismo
2.
Nat Commun ; 11(1): 2664, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32471982

RESUMO

Controlling the chemical glycosylation reaction remains the major challenge in the synthesis of oligosaccharides. Though 1,2-trans glycosidic linkages can be installed using neighboring group participation, the construction of 1,2-cis linkages is difficult and has no general solution. Long-range participation (LRP) by distal acyl groups may steer the stereoselectivity, but contradictory results have been reported on the role and strength of this stereoelectronic effect. It has been exceedingly difficult to study the bridging dioxolenium ion intermediates because of their high reactivity and fleeting nature. Here we report an integrated approach, using infrared ion spectroscopy, DFT computations, and a systematic series of glycosylation reactions to probe these ions in detail. Our study reveals how distal acyl groups can play a decisive role in shaping the stereochemical outcome of a glycosylation reaction, and opens new avenues to exploit these species in the assembly of oligosaccharides and glycoconjugates to fuel biological research.


Assuntos
Química Computacional/métodos , Oligossacarídeos/síntese química , Compostos de Selênio/química , Configuração de Carboidratos , Galactose/química , Glucose/química , Glicosilação , Manose/química , Espectrofotometria Infravermelho
3.
Chemistry ; 26(51): 11782-11795, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32253776

RESUMO

Synthetic carbohydrate receptors (SCRs) that selectively recognize cell-surface glycans could be used for detection, drug delivery, or as therapeutics. Here we report the synthesis of seven new C2h symmetric tetrapodal SCRs. The structures of these SCRs possess a conserved biaryl core, and they vary in the four heterocyclic binding groups that are linked to the biaryl core via secondary amines. Supramolecular association between these SCRs and five biologically relevant C1 -O-octyloxy glycans, α/ß-glucoside (α/ß-Glc), α/ß-mannoside (α/ß-Man), and ß-galactoside (ß-Gal), was studied by mass spectrometry, 1 H NMR titrations, and molecular modeling. These studies revealed that selectivity can be achieved in these tetrapodal SCRs by varying the heterocyclic binding group. We found that SCR017 (3-pyrrole), SCR021 (3-pyridine), and SCR022 (2-phenol) bind only to ß-Glc. SCR019 (3-indole) binds only to ß-Man. SCR020 (2-pyridine) binds ß-Man and α-Man with a preference to the latter. SCR018 (2-indole) binds α-Man and ß-Gal with a preference to the former. The glycan guests bound within their SCR hosts in one of three supramolecular geometries: center-parallel, center-perpendicular, and off-center. Many host-guest combinations formed higher stoichiometry complexes, 2:1 glycan⋅SCR or 1:2 glycan⋅SCR, where the former are driven by positive allosteric cooperativity induced by glycan-glycan contacts.


Assuntos
Carboidratos/síntese química , Lectinas Tipo C/química , Lectinas de Ligação a Manose/química , Manose/síntese química , Polissacarídeos/química , Receptores Artificiais/química , Receptores de Superfície Celular/química , Carboidratos/química , Espectroscopia de Ressonância Magnética , Manose/química , Modelos Moleculares , Estrutura Molecular
4.
Chin J Nat Med ; 18(3): 219-225, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32245592

RESUMO

The rapid detection of pathogenic bacteria is vital for the prevention of outbreaks of infectious diseases, including infections by the common foodborne bacteria E.coli and Salmonella Carbohydrate microarrays have been developed as a powerful method to investigate carbohydrate-protein interaction with only very small amounts of glycans, which show great potential for detect the carbohydrate mediated interaction with pathogens. Here, different mannose-coated microarrays were constructed and tested with E.coli (K-12 and BL-21) and Salmonella enterica strains (ATCC9184 and ATCC31685) exhibiting different mannose binding affinities. The optimized carbohydrate microarray was then applied to test the binding of 12 Salmonella enterica and 9 E.coli isolates from local patients for the first time and showed strong binding with certain serovars or subtypes. The results showed that microarray probed with the single mannose structure is not enough for the detection of bacteria with various serovars or subtypes, which contain a high degree of allelic variation in adhesin. We suggest that a complex carbohydrate microarray containing different glycan conformation may be needed for detection of different bacteria isolates.


Assuntos
Carboidratos/química , Escherichia coli/isolamento & purificação , Análise em Microsséries/métodos , Salmonella enterica/isolamento & purificação , Adesinas Bacterianas/química , Contaminação de Alimentos , Microbiologia de Alimentos , Humanos , Manose/química , Polissacarídeos/química
5.
Nat Commun ; 11(1): 899, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060313

RESUMO

The human gut microbiota plays a central role not only in regulating the metabolism of nutrients but also promoting immune homeostasis, immune responses and protection against pathogen colonization. The genome of the Gram-negative symbiont Bacteroides thetaiotaomicron, a dominant member of the human intestinal microbiota, encodes polysaccharide utilization loci PULs, the apparatus required to orchestrate the degradation of a specific glycan. EndoBT-3987 is a key endo-ß-N-acetylglucosaminidase (ENGase) that initiates the degradation/processing of mammalian high-mannose-type (HM-type) N-glycans in the intestine. Here, we provide structural snapshots of EndoBT-3987, including the unliganded form, the EndoBT-3987-Man9GlcNAc2Asn substrate complex, and two EndoBT-3987-Man9GlcNAc and EndoBT-3987-Man5GlcNAc product complexes. In combination with alanine scanning mutagenesis and activity measurements we unveil the molecular mechanism of HM-type recognition and specificity for EndoBT-3987 and an important group of the GH18 ENGases, including EndoH, an enzyme extensively used in biotechnology, and for which the mechanism of substrate recognition was largely unknown.


Assuntos
Bacteroides thetaiotaomicron/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteroides thetaiotaomicron/química , Bacteroides thetaiotaomicron/enzimologia , Bacteroides thetaiotaomicron/genética , Microbioma Gastrointestinal , Regulação Bacteriana da Expressão Gênica , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Humanos , Manose/química , Manose/metabolismo , Especificidade por Substrato
6.
J Virol ; 94(7)2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-31915280

RESUMO

Dengue virus (DENV) is a mosquito-borne flavivirus responsible for dengue disease, a major human health concern for which no specific therapies are available. Like other viruses, DENV relies heavily on the host cellular machinery for productive infection. In this study, we performed a genome-wide CRISPR-Cas9 screen using haploid HAP1 cells to identify host genes important for DENV infection. We identified DPM1 and -3, two subunits of the endoplasmic reticulum (ER) resident dolichol-phosphate mannose synthase (DPMS) complex, as host dependency factors for DENV and other related flaviviruses, such as Zika virus (ZIKV). The DPMS complex catalyzes the synthesis of dolichol-phosphate mannose (DPM), which serves as mannosyl donor in pathways leading to N-glycosylation, glycosylphosphatidylinositol (GPI) anchor biosynthesis, and C- or O-mannosylation of proteins in the ER lumen. Mutation in the DXD motif of DPM1, which is essential for its catalytic activity, abolished DPMS-mediated DENV infection. Similarly, genetic ablation of ALG3, a mannosyltransferase that transfers mannose to lipid-linked oligosaccharide (LLO), rendered cells poorly susceptible to DENV. We also established that in cells deficient for DPMS activity, viral RNA amplification is hampered and truncated oligosaccharides are transferred to the viral prM and E glycoproteins, affecting their proper folding. Overall, our study provides new insights into the host-dependent mechanisms of DENV infection and supports current therapeutic approaches using glycosylation inhibitors to treat DENV infection.IMPORTANCE Dengue disease, which is caused by dengue virus (DENV), has emerged as the most important mosquito-borne viral disease in humans and is a major global health concern. DENV encodes only few proteins and relies on the host cell machinery to accomplish its life cycle. The identification of the host factors important for DENV infection is needed to propose new targets for antiviral intervention. Using a genome-wide CRISPR-Cas9 screen, we identified DPM1 and -3, two subunits of the DPMS complex, as important host factors for the replication of DENV as well as other related viruses such as Zika virus. We established that DPMS complex plays dual roles during viral infection, both regulating viral RNA replication and promoting viral structural glycoprotein folding/stability. These results provide insights into the host molecules exploited by DENV and other flaviviruses to facilitate their life cycle.


Assuntos
Sistemas CRISPR-Cas , Vírus da Dengue/fisiologia , Dengue/virologia , Manosiltransferases/metabolismo , Animais , Chlorocebus aethiops , Retículo Endoplasmático/metabolismo , Fibroblastos/metabolismo , Glicoproteínas/metabolismo , Glicosilação , Glicosilfosfatidilinositóis/metabolismo , Células HEK293 , Humanos , Manose/química , Oligossacarídeos/química , RNA Guia/metabolismo , RNA Viral/química , Células Vero , Replicação Viral
7.
Proc Natl Acad Sci U S A ; 117(3): 1438-1446, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31900356

RESUMO

Feline infectious peritonitis virus (FIPV) is an alphacoronavirus that causes a nearly 100% mortality rate without effective treatment. Here we report a 3.3-Å cryoelectron microscopy (cryo-EM) structure of the serotype I FIPV spike (S) protein, which is responsible for host recognition and viral entry. Mass spectrometry provided site-specific compositions of densely distributed high-mannose and complex-type N-glycans that account for 1/4 of the total molecular mass; most of the N-glycans could be visualized by cryo-EM. Specifically, the N-glycans that wedge between 2 galectin-like domains within the S1 subunit of FIPV S protein result in a unique propeller-like conformation, underscoring the importance of glycosylation in maintaining protein structures. The cleavage site within the S2 subunit responsible for activation also showed distinct structural features and glycosylation. These structural insights provide a blueprint for a better molecular understanding of the pathogenesis of FIP.


Assuntos
Coronavirus Felino/química , Glicoproteína da Espícula de Coronavírus/química , Microscopia Crioeletrônica , Galectinas/química , Glicosilação , Células HEK293 , Humanos , Manose/química , Conformação Proteica
8.
AAPS PharmSciTech ; 21(1): 13, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31807947

RESUMO

The launched hepatitis B vaccine could induce powerful antibodies, whereas it failed to improve potent cellular immune responses due to that the Th2-type response-induced aluminum adjuvant was adopted. Here, to target antigen-presenting cells under the epidermis and induce potent cellular and humoral immune responses, mannose-modified poly D,L-lactide-co-glycolic acid (PLGA) was synthesized and nanoparticle (MNP)-loaded hepatitis B surface antigen (HBsAg) protein was prepared. HBsAg could be slowly released and highly presented to lymphocytes which facilitated to produce long-lasting immunity based on characters of PLGA. In vitro uptake test results showed that MNPs could enhance internalization in bone marrow-derived dendritic cells (BMDCs) and RAW 264.7 cells. Subcutaneous delivery of MNPs into mice kept humoral immune and strengthened cellular immune responses. Experimental results indicated that MNPs showed significantly modified properties compared with parental PLGA nanoparticles. Thus, the obtained MNPs could be a promising vehicle for hepatitis B vaccine delivery.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/efeitos dos fármacos , Imunização/métodos , Manose/administração & dosagem , Nanopartículas/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Animais , Sistemas de Liberação de Medicamentos/métodos , Excipientes/administração & dosagem , Excipientes/química , Feminino , Antígenos de Superfície da Hepatite B/administração & dosagem , Vacinas contra Hepatite B/química , Vírus da Hepatite B/imunologia , Manose/química , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Células RAW 264.7
9.
Int J Mol Sci ; 20(24)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817246

RESUMO

Aging represents the accumulation of changes in an individual over time, encompassing physical, psychological, and social changes. Posttranslational modifications of proteins such as glycosylation, including sialylation or glycation, are proposed to be involved in this process, since they modulate a variety of molecular and cellular functions. In this study, we analyzed selected posttranslational modifications and the respective proteins on which they occur in young and old mouse brains. The expression of neural cell adhesion molecule (NCAM), receptor for advanced glycation endproducts (RAGE), as well as the carbohydrate-epitopes paucimannose and high-mannose, polysialic acid, and O-GlcNAc were examined. We demonstrated that mannose-containing glycans increased on glycoproteins in aged mouse brains and identified synapsin-1 as one major carrier of paucimannose in aged brains. In addition, we found an accumulation of so-called advanced glycation endproducts, which are generated by non-enzymatic reactions and interfere with protein function. Furthermore, we analyzed the expression of sialic acid and found also an increase during aging.


Assuntos
Envelhecimento , Encéfalo/metabolismo , Glicoproteínas/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Produtos Finais de Glicação Avançada/metabolismo , Glicoproteínas/análise , Glicosilação , Masculino , Manose/química , Manose/metabolismo , Espectrometria de Massas , Camundongos , Ácido N-Acetilneuramínico/análise , Moléculas de Adesão de Célula Nervosa/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo
10.
Elife ; 82019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31868591

RESUMO

Previous studies demonstrated importance of C-mannosylation for efficient protein secretion. To study its impact on protein folding and stability, we analyzed both C-mannosylated and non-C-mannosylated thrombospondin type 1 repeats (TSRs) of netrin receptor UNC-5. In absence of C-mannosylation, UNC-5 TSRs could only be obtained at low temperature and a significant proportion displayed incorrect intermolecular disulfide bridging, which was hardly observed when C-mannosylated. Glycosylated TSRs exhibited higher resistance to thermal and reductive denaturation processes, and the presence of C-mannoses promoted the oxidative folding of a reduced and denatured TSR in vitro. Molecular dynamics simulations supported the experimental studies and showed that C-mannoses can be involved in intramolecular hydrogen bonding and limit the flexibility of the TSR tryptophan-arginine ladder. We propose that in the endoplasmic reticulum folding process, C-mannoses orient the underlying tryptophan residues and facilitate the formation of the tryptophan-arginine ladder, thereby influencing the positioning of cysteines and disulfide bridging.


Assuntos
Proteínas de Caenorhabditis elegans/química , Manose/química , Proteínas de Membrana/química , Dobramento de Proteína , Receptores de Superfície Celular/química , Trombospondinas/química , Animais , Arginina/química , Caenorhabditis elegans/química , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/ultraestrutura , Cisteína/química , Dissulfetos/química , Drosophila melanogaster/química , Drosophila melanogaster/genética , Retículo Endoplasmático/química , Retículo Endoplasmático/genética , Glicosilação , Ligação de Hidrogênio , Manose/genética , Proteínas de Membrana/genética , Simulação de Dinâmica Molecular , Conformação Proteica , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/ultraestrutura , Trombospondinas/genética , Triptofano/química , Triptofano/genética
11.
Carbohydr Res ; 486: 107822, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31600611

RESUMO

Size exclusion chromatography of short chain ß-manno-oligosaccharides (GG-ß-MOS) produced after endo-mannanase (ManB-1601) hydrolysis of guar gum resulted in seven (P1-P7) peaks. Electron spray ionization mass-spectrometry (ESI-MS) revealed P3, P4, P5 and P6 peaks as pentasaccharide (DP5), tetrasaccharide (DP4), trisaccharide (DP3) and disaccharide (DP2), respectively. DP2 and DP3 GG-ß-MOS were structurally characterized by NMR (1H and 13C), FTIR and XRD. DP2 GG-ß-MOS was composed of two species (A) mannopyranose ß-1,4 mannopyranose and (B) α-1,6-galactosyl-mannopyranose while, DP3 oligosaccharide showed presence of three species i.e. (A) α-d-galactosyl-ß-d-mannobiose (galactosyl residue at reducing end), (B) α-d-galactosyl-ß-d-mannobiose (galactosyl residue at non-reducing end) and (C) mannopyranose ß-1,4 mannose ß-1,4 mannopyranose. In batch fermentation, DP2 GG-ß-MOS was preferred over DP3 by all Lactobacillus sp. except Lactobacillus casei var rhamnosus. DP2/DP3 and GG-ß-MOS mixture inhibited the growth of enteropathogens in monoculture and co-culture fermentations, respectively. Fermentation of GG-ß-MOS mixture by Lactobacillus sp. produced short chain fatty acids.


Assuntos
Galactanos/química , Mananas/química , Manose/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Gomas Vegetais/química , Prebióticos , beta-Manosidase/metabolismo , Bactérias/metabolismo , Fermentação , Hidrólise , Prebióticos/microbiologia
12.
Food Chem Toxicol ; 133: 110778, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472224

RESUMO

This study was to investigate the structure of a polysaccharide fraction from the Fortunella margarita and the relationship between its digestibility and structure. A novel polysaccharide fraction extracted by graded precipitation at ethanol concentrations of 20% from F. margarita (named FP20) comprised mainly glucose, galactose, and mannose. The unit composition was →4)-ß-Glcp-(1 → 2)-α-Glcp-(1 → 2)-α-Galp-(1 → 4)-α-Galp-(1→ bone, and in →2)-α-Galp-(1→) with a branching point at C6 of ß-Manp. FP20 was identified as a mannogalactoglucan with a different monosaccharide composition ratio and side-chain sugar residues compared with other plant polysaccharides. Moreover, FP20 had a spherical aggregations by atomic force microscope test. FP20 had an island-shaped structures with a smooth surface revealed by field emission scanning electron microscopy. Furthermore, in vitro digestive test, FP20 was resistance to a digestion system of saliva-gastric-small intestinal. The digestibility of FP20 was related to its backbone unit, structure and tight, uniform, and spherical chain conformation in aqueous.


Assuntos
Digestão , Galactanos/química , Glucanos/química , Rutaceae/química , Sequência de Carboidratos , Suco Gástrico/química , Hidrólise , Secreções Intestinais/química , Manose/química , Peso Molecular , Saliva/química
13.
Colloids Surf B Biointerfaces ; 183: 110383, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450058

RESUMO

Preventing microorganism colonization on a surface is a great challenge in the conception of medical, food and marine devices. Here, we describe the formation of carbohydrate functionalized glass surfaces with D-glucose, D-galactose and D-mannose and how they efficiently affected the bacterial attachment. The carbohydrate entities were covalently attached to the pre-functionalized surface by click chemistry thanks the copper catalysed alkyl-azide cycloaddition. Water contact angle and X-ray photoelectron spectroscopy characterisations showed a homogeneous and quantitative cycloaddition at the scale of microorganisms. The adhesion assays with Pseudomonas aeruginosa, used as model of opportunistic pathogen, indicated a significant diminution of almost 40% of the bacterial accumulation on glycosidic surfaces with respect to initial surface. This activity was further compared with a surface presenting a simple hydroxyl residue. Exploration of specific interactions through Lectin A deficient Pseudomonas aeruginosa mutant strain provided new evidences that Lectin A was involved in biofilm maturation, rather than bacterial attachment. Subsequently, the determination of surface free energy and the adhesion free energy between surfaces and bacterial cell wall showed that the adhesion was thermodynamically unfavourable.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Vidro/análise , Pseudomonas aeruginosa/efeitos dos fármacos , Azidas/química , Biofilmes/crescimento & desenvolvimento , Química Click , Reação de Cicloadição , Galactose/química , Galactose/farmacologia , Vidro/química , Glucose/química , Glucose/farmacologia , Manose/química , Manose/farmacologia , Mitógenos da Erva-dos-Cancros/química , Mitógenos da Erva-dos-Cancros/metabolismo , Pseudomonas aeruginosa/fisiologia , Propriedades de Superfície , Termodinâmica
14.
Int J Biol Macromol ; 140: 234-244, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400430

RESUMO

Carbohydrate-binding proteins, also known as lectins, are valuable tools for biotechnology, including pharmacological uses. Mannose lectins obtained from plant and animal sources are applied to protection and characterization of autoimmune diseases as well as defense proteins against pathogens. The presence of mannose-binding lectins in plants that also recognize glucose could be entitled Man/Glc lectins; such specificity has allowed employing these vegetal lectins for several applications. Animal mannose-binding lectins are synthesized in the liver and secreted into the blood stream where both concentration and activity are greatly affected due to gene polymorphisms; these serum proteins play important roles in the immune system by recognizing mannose-like carbohydrate ligands found exclusively on pathogenic microorganisms. Mannose lectins already showed strong binding to relevant bacteria, viruses, protozoa and helminth species, initiating potent host defense mechanisms by inducing growth inhibition or death of such organisms; the ability to prevent the formation or destruction of microbial biofilms has also been reported. Mannose-binding lectins have attracted considerable attention against carcinogenesis and atherogenesis. The aim of this review article is to approach biotechnology characteristics of these lectins from different sources and microorganism/cell surface interactions with mannose; in addition, aspects of mechanisms associated to lectin antipathogenic activities are described.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Lectinas/farmacologia , Lectinas de Ligação a Manose/farmacologia , Plantas/química , Animais , Anti-Infecciosos/química , Antineoplásicos Fitogênicos/química , Sítios de Ligação , Biotecnologia , Proliferação de Células/efeitos dos fármacos , Glicosilação , Lectinas/química , Manose/química , Manose/metabolismo , Lectinas de Ligação a Manose/química , Modelos Moleculares , Lectinas de Plantas/farmacologia , Ligação Proteica
15.
Nat Nanotechnol ; 14(9): 891-901, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384037

RESUMO

A low response rate, acquired resistance and severe side effects have limited the clinical outcomes of immune checkpoint therapy. Here, we show that combining cancer nanovaccines with an anti-PD-1 antibody (αPD-1) for immunosuppression blockade and an anti-OX40 antibody (αOX40) for effector T-cell stimulation, expansion and survival can potentiate the efficacy of melanoma therapy. Prophylactic and therapeutic combination regimens of dendritic cell-targeted mannosylated nanovaccines with αPD-1/αOX40 demonstrate a synergism that stimulates T-cell infiltration into tumours at early treatment stages. However, this treatment at the therapeutic regimen does not result in an enhanced inhibition of tumour growth compared to αPD-1/αOX40 alone and is accompanied by an increased infiltration of myeloid-derived suppressor cells in tumours. Combining the double therapy with ibrutinib, a myeloid-derived suppressor cell inhibitor, leads to a remarkable tumour remission and prolonged survival in melanoma-bearing mice. The synergy between the mannosylated nanovaccines, ibrutinib and αPD-1/αOX40 provides essential insights to devise alternative regimens to improve the efficacy of immune checkpoint modulators in solid tumours by regulating the endogenous immune response.


Assuntos
Vacinas Anticâncer/administração & dosagem , Portadores de Fármacos/química , Manose/química , Melanoma/terapia , Nanopartículas/química , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Imunização , Masculino , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microambiente Tumoral
16.
Mar Drugs ; 17(8)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357490

RESUMO

To date, a number of mannose-specific lectins have been isolated and characterized from seaweeds, especially from red algae. In fact, man-specific seaweed lectins consist of different structural scaffolds harboring a single or a few carbohydrate-binding sites which specifically recognize mannose-containing glycans. Depending on the structural scaffold, man-specific seaweed lectins belong to five distinct structurally-related lectin families, namely (1) the griffithsin lectin family (ß-prism I scaffold); (2) the Oscillatoria agardhii agglutinin homolog (OAAH) lectin family (ß-barrel scaffold); (3) the legume lectin-like lectin family (ß-sandwich scaffold); (4) the Galanthus nivalis agglutinin (GNA)-like lectin family (ß-prism II scaffold); and, (5) the MFP2-like lectin family (MFP2-like scaffold). Another algal lectin from Ulva pertusa, has been inferred to the methanol dehydrogenase related lectin family, because it displays a rather different GlcNAc-specificity. In spite of these structural discrepancies, all members from the five lectin families share a common ability to specifically recognize man-containing glycans and, especially, high-mannose type glycans. Because of their mannose-binding specificity, these lectins have been used as valuable tools for deciphering and characterizing the complex mannose-containing glycans from the glycocalyx covering both normal and transformed cells, and as diagnostic tools and therapeutic drugs that specifically recognize the altered high-mannose N-glycans occurring at the surface of various cancer cells. In addition to these anti-cancer properties, man-specific seaweed lectins have been widely used as potent human immunodeficiency virus (HIV-1)-inactivating proteins, due to their capacity to specifically interact with the envelope glycoprotein gp120 and prevent the virion infectivity of HIV-1 towards the host CD4+ T-lymphocyte cells in vitro.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Lectinas de Ligação a Manose/química , Lectinas de Ligação a Manose/farmacologia , Manose/química , Manose/farmacologia , Rodófitas/química , Sequência de Aminoácidos , Animais , Humanos
17.
Mater Sci Eng C Mater Biol Appl ; 103: 109777, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349400

RESUMO

Tuberculosis (TB), caused by M.tuberculosis (Mtb), has become a top killer among infectious diseases. Enhancing the ability of anti-TB drugs to kill intracellular Mtb in host cells remains a big challenge. Here, an innovative nano-system was developed to increase drug delivery and Mtb-killing efficacy in Mtb-infected macrophages. We employed mannose surface decoration to develop mannosylated and PEGylated graphene oxide (GO-PEG-MAN). Such nano-platform exhibited increased uptake by macrophages via mannose receptor-mediated endocytosis in vitro. Interestingly, drug-loaded GO-PEG-MAN was preferentially up-taken by mannose receptor-expressing mucosal CD14+ macrophages isolated from Mtb-infected rhesus macaques than drug-loaded GO-PEG. Consistently, the drug concentration was also significantly higher in macrophages than that in T and B cells expressing no or low mannose receptor, implicating a useful macrophage/mannose receptor-targeted drug-delivery system relevant to the in vivo settings. Concurrently, rifampicin-loaded GO-PEG-MAN (Rif@GO-PEG-MAN) significantly increased rifampicin uptake, inducing long-lasting higher concentration of rifampicin in macrophages. Such innovative Rif@GO-PEG-MAN could readily get into the lysosomes of the Mtb host cells, where rifampicin underwent an accelerated release in acidic lysosomic condition, leading to explosive rifampicin release after cell entry for more effective killing of intracellular Mtb. Most importantly, Rif@GO-PEG-MAN-enhanced intracellular rifampicin delivery and pharmacokinetics significantly increased the efficacy of rifampicin-driven killing of intracellular BCG and Mtb bacilli in infected macrophages both in vitro and ex vivo. Such innovative nanocarrier approach may potentially enhance anti-TB drug efficacy and reduce drug side effects.


Assuntos
Sistemas de Liberação de Medicamentos , Grafite , Macrófagos , Manose , Mycobacterium tuberculosis/metabolismo , Nanopartículas , Rifampina , Tuberculose , Animais , Grafite/química , Grafite/farmacocinética , Grafite/farmacologia , Humanos , Macaca mulatta , Macrófagos/metabolismo , Macrófagos/microbiologia , Macrófagos/patologia , Manose/química , Manose/farmacocinética , Manose/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Rifampina/química , Rifampina/farmacocinética , Rifampina/farmacologia , Células THP-1 , Tuberculose/tratamento farmacológico , Tuberculose/metabolismo , Tuberculose/patologia
18.
Macromol Biosci ; 19(9): e1900124, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31310440

RESUMO

Multivalent carbohydrate-lectin interactions play a crucial role in bacterial infection. Biomimicry of multivalent glycosystems represents a major strategy in the repression of bacterial growth. In this study, a new kind of glycopeptide (Naphthyl-Phe-Phe-Ser-Tyr, NMY) scaffold with mannose modification is designed and synthesized, which is able to perform supramolecular self-assembly with the assistance of catalytic enzyme, and present multiple mannose ligands on its self-assembled structure to target mannose-binding proteins. Relying on multivalent carbohydrate-lectin interactions, the glycopeptide hydrogel is able to bind Escherichia coli (E. coli) in high specificity, and result in bacterial adhesion, membrane disruption and subsequent cell death. In vivo wound healing assays reveal that this glycopeptide hydrogel exhibits considerable potentials for promoting wound healing and preventing E. coli infection in a full-thickness skin defect mouse model. Therefore, through a specific mannose-lectin interaction, a biocompatible hydrogel with inherent antibacterial activity against E. coli is achieved without the need to resort to antibiotic or antimicrobial agent treatment, highlighting the potential role of sugar-coated nanomaterials in wound healing and control of bacterial pathogenesis.


Assuntos
Anti-Infecciosos/farmacologia , Escherichia coli/efeitos dos fármacos , Glicopeptídeos/farmacologia , Hidrogéis/farmacologia , Lectinas/metabolismo , Manose/química , Animais , Materiais Biocompatíveis/farmacologia , Escherichia coli/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Pele/efeitos dos fármacos , Pele/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Cicatrização/efeitos dos fármacos
19.
Mar Drugs ; 17(7)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284525

RESUMO

Amongst Aeromonas spp. strains that are pathogenic to fish in Polish aquacultures, serogroup O6 was one of the five most commonly identified immunotypes especially among carp isolates. Here, we report immunochemical studies of the lipopolysaccharide (LPS) including the O-specific polysaccharide (O-antigen) of A. veronii bv. sobria strain K557, serogroup O6, isolated from a common carp during an outbreak of motile aeromonad septicemia (MAS) on a Polish fish farm. The O-polysaccharide was obtained by mild acid degradation of the LPS and studied by chemical analyses, mass spectrometry, and 1H and 13C NMR spectroscopy. It was revealed that the O-antigen was composed of two O-polysaccharides, both containing a unique sugar 4-amino-4,6-dideoxy-L-mannose (N-acetyl-L-perosamine, L-Rhap4NAc). The following structures of the O-polysaccharides (O-PS 1 and O-PS 2) were established.


Assuntos
Aeromonas veronii/química , Antígenos/química , Manose/análogos & derivados , Antígenos O/química , Açúcares/química , Animais , Carboidratos , Carpas , Pesqueiros , Cromatografia Gasosa-Espectrometria de Massas/métodos , Infecções por Bactérias Gram-Negativas/microbiologia , Lipopolissacarídeos/química , Espectroscopia de Ressonância Magnética/métodos , Manose/química , Polônia , Sorogrupo
20.
Macromol Rapid Commun ; 40(18): e1900215, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31294497

RESUMO

Searching for vaccines (antigen and adjuvant) with easy preparation and strong T-cell response are crucial for antitumor immunity. In this work, to design lymphoseek-inspired vaccine possessing the abilities of promoting vaccine internalization and enhancing CD8+ T-cell responses, a simple multicomponent strategy is successfully utilized to fabricate lymph node and dendritic cell dual-targeting glycoadjuvant@AuNPs in one pot, where three different components, catechol-containing glycopolymer, HAuCl4 , and amine-terminal CpG (CpG-NH2 ) can react in a single step to generate target adjuvant. It is found that hetero-glycoadjuvant@AuNPs could increase adjuvant internalization and enhance the activation of bone-marrow-derived dendritic cells. Critically, lymphoseek-inspired vaccine potentiates antigen-specific CD8+ T-cell immune responses.


Assuntos
Adjuvantes Imunológicos/química , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Ouro/química , Linfonodos/imunologia , Nanopartículas Metálicas/química , Adjuvantes Imunológicos/síntese química , Animais , Catecóis/química , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Glucose/química , Imunogenicidade da Vacina , Linfonodos/efeitos dos fármacos , Manose/química , Camundongos
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