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1.
Biosci Biotechnol Biochem ; 84(3): 594-597, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31760857

RESUMO

Reg3ß, a lectin, displays antibacterial activity. This study investigated Reg3ß-expressing cells using IL-22-stimulated enteroids. IL-22 stimulation elevated the mRNA and protein levels of Reg3ß. IL-22 also increased the mRNA levels of CD133 (a transit-amplifying cell marker) and lysozyme (a Paneth cell marker). Immunohistochemistry showed partial colocalization of Reg3ß- and lysozyme-positive cells, suggesting that Paneth cells are one of Reg3ß-producing cells.


Assuntos
Lectinas/biossíntese , Celulas de Paneth/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Interleucinas/farmacologia , Lectinas/genética , Lectinas/metabolismo , Celulas de Paneth/metabolismo
2.
Chem Commun (Camb) ; 56(3): 360-363, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31825399

RESUMO

A crystalline biohybrid with a 4 : 1 protein : cucurbituril mass ratio is presented. This result was achieved by engineering additional cucurbit[7]uril (Q7) binding sites into a ß-propeller protein. In contrast to the parent protein, Q7-controlled assembly of the engineered variant occurred in solution, as evidenced by NMR and SAXS measurements.


Assuntos
Proteínas de Bactérias/química , Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Imidazóis/metabolismo , Lectinas/química , Lectinas/genética , Lectinas/metabolismo , Ressonância Magnética Nuclear Biomolecular , Ralstonia solanacearum/metabolismo , Espalhamento a Baixo Ângulo , Difração de Raios X
3.
PLoS Pathog ; 15(12): e1008168, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31869396

RESUMO

We report here two cases of Herpes simplex virus encephalitis (HSE) in adult patients with very rare, previously uncharacterized, non synonymous heterozygous G634R and R203W substitution in mannan-binding lectin serine protease 2 (MASP2), a gene encoding a key protease of the lectin pathway of the complement system. None of the 2 patients had variants in genes involved in the TLR3-interferon signaling pathway. Both MASP2 variants induced functional defects in vitro, including a reduced (R203W) or abolished (G634R) protein secretion, a lost capability to cleave MASP-2 precursor into its active form (G634R) and an in vivo reduced antiviral activity (G634R). In a murine model of HSE, animals deficient in mannose binding lectins (MBL, the main pattern recognition molecule associated with MASP-2) had a decreased survival rate and an increased brain burden of HSV-1 compared to WT C57BL/6J mice. Altogether, these data suggest that MASP-2 deficiency can increase susceptibility to adult HSE.


Assuntos
Encefalite por Herpes Simples/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/deficiência , Adulto , Animais , Encefalite por Herpes Simples/genética , Encefalite por Herpes Simples/imunologia , Humanos , Imunidade Inata/genética , Lectinas/genética , Lectinas/metabolismo , Masculino , Lectina de Ligação a Manose/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
4.
Biochem Soc Trans ; 47(6): 1569-1579, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31724699

RESUMO

Bacterial surfaces are rich in glycoconjugates that are mainly present in their outer layers and are of great importance for their interaction with the host innate immune system. The innate immune system is the first barrier against infection and recognizes pathogens via conserved pattern recognition receptors (PRRs). Lectins expressed by innate immune cells represent an important class of PRRs characterized by their ability to recognize carbohydrates. Among lectins in innate immunity, there are three major classes including the galectins, siglecs, and C-type lectin receptors. These lectins may contribute to initial recognition of bacterial glycans, thus providing an early defence mechanism against bacterial infections, but they may also be exploited by bacteria to escape immune responses. In this review, we will first exemplify bacterial glycosylation systems; we will then describe modes of recognition of bacterial glycans by lectins in innate immunity and, finally, we will briefly highlight how bacteria have found ways to exploit these interactions to evade immune recognition.


Assuntos
Imunidade Inata , Lectinas/metabolismo , Polissacarídeos/metabolismo , Animais , Bactérias/metabolismo , Glicosilação , Humanos , Ligação Proteica
5.
Chem Biodivers ; 16(12): e1900401, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31654480

RESUMO

The complement system participates in host defense by eliminating microorganisms and triggering inflammation. However, insufficient control or exacerbated complement activation contributes to inflammatory diseases. Since promising antioxidant and anti-inflammatory activities have been identified in Arctium lappa L. extracts, this study aims to explore the effect of A. lappa extracts on the lectin pathway (LP) of complement activation. Four extracts were obtained by supercritical extraction using scCO2 with or without ethanol as co-solvent, at different temperatures and pressures (E1: 2.2 mg/mL, E2: 2.6 mg/mL and E3: 2.0 mg/mL, E4: 1.5 mg/mL). To evaluate the effect of A. lappa extracts on the LP activation, an ELISA assay using mannose binding lectin pathway of complement was carried out with C4 detection. All extracts showed a concentration-dependent inhibitory effect on the activation of complement by the LP. The following IC50 were observed for E1, E2, E3 and E4: 179.4 µg/mL, 74.69 µg/mL, 119.1 µg/mL and 72.19 µg/mL, respectively. Our results suggest that A. lappa extracts are potential candidates for the treatment of inflammatory disorders that are complement-related.


Assuntos
Arctium/química , Cromatografia com Fluido Supercrítico/métodos , Proteínas do Sistema Complemento/metabolismo , Lectinas/metabolismo , Extratos Vegetais/química , Arctium/metabolismo , Dióxido de Carbono/química , Proteínas do Sistema Complemento/agonistas , Lectinas/antagonistas & inibidores , Folhas de Planta/química , Folhas de Planta/metabolismo , Temperatura Ambiente
6.
Adv Clin Chem ; 93: 1-61, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31655728

RESUMO

Cancer has high incidence and it will continue to increase over the next decades. Detection and quantification of cancer-associated biomarkers is frequently carried out for diagnosis, prognosis and treatment monitoring at various disease stages. It is well-known that glycosylation profiles change significantly during oncogenesis. Aberrant glycans produced during tumorigenesis are, therefore, valuable molecules for detection and characterization of cancer, and for therapeutic design and monitoring. Although glycoproteomics has benefited from the development of analytical tools such as high performance liquid chromatography, two-dimensional gel and capillary electrophoresis and mass spectrometry, these approaches are not well suited for rapid point-of-care (POC) testing easily performed by medical staff. Lectins are biomolecules found in nature with specific affinities toward particular glycan structures and bind them thus forming a relatively strong complex. Because of this characteristic, lectins have been used in analytical techniques for the selective capture or separation of certain glycans in complex samples, namely, in lectin affinity chromatography, or to characterize glycosylation profiles in diverse clinical situations, using lectin microarrays. Lectin-based biosensors have been developed for the detection of specific aberrant and cancer-associated glycostructures to aid diagnosis, prognosis and treatment assessment of these patients. The attractive features of biosensors, such as portability and simple use make them highly suitable for POC testing. Recent developments in lectin biosensors, as well as their potential and pitfalls in cancer glycan biomarker detection, are presented in this chapter.


Assuntos
Biomarcadores Tumorais/metabolismo , Técnicas Biossensoriais , Lectinas/metabolismo , Neoplasias/metabolismo , Polissacarídeos/metabolismo , Humanos
7.
Nat Commun ; 10(1): 4752, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628314

RESUMO

Meningococcus utilizes ß-arrestin selective activation of endothelial cell ß2 adrenergic receptor (ß2AR) to cause meningitis in humans. Molecular mechanisms of receptor activation by the pathogen and of its species selectivity remained elusive. We report that ß2AR activation requires two asparagine-branched glycan chains with terminally exposed N-acetyl-neuraminic acid (sialic acid, Neu5Ac) residues located at a specific distance in its N-terminus, while being independent of surrounding amino-acid residues. Meningococcus triggers receptor signaling by exerting direct and hemodynamic-promoted traction forces on ß2AR glycans. Similar activation is recapitulated with beads coated with Neu5Ac-binding lectins, submitted to mechanical stimulation. This previously unknown glycan-dependent mode of allosteric mechanical activation of a G protein-coupled receptor contributes to meningococcal species selectivity, since Neu5Ac is only abundant in humans due to the loss of CMAH, the enzyme converting Neu5Ac into N-glycolyl-neuraminic acid in other mammals. It represents an additional mechanism of evolutionary adaptation of a pathogen to its host.


Assuntos
Fímbrias Bacterianas/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Neisseria meningitidis/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Animais , Linhagem Celular , Membrana Celular/metabolismo , Fímbrias Bacterianas/genética , Células HEK293 , Humanos , Lectinas/metabolismo , Microscopia Confocal , Neisseria meningitidis/fisiologia , Polissacarídeos/metabolismo , Receptores Adrenérgicos beta 2/genética , Homologia de Sequência de Aminoácidos , beta-Arrestinas/metabolismo
8.
Int J Mol Sci ; 20(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540487

RESUMO

We determined the primary structures of jacalin-related lectins termed PPL3s (PPL3A, 3B, and 3C, which are dimers consisting of sequence variants α + α, α + ß, ß + ß, respectively) and PPL4, which is heterodimer consisting of α + ß subunits, isolated from mantle secretory fluid of Pteria penguin (Mabe) pearl shell. Their carbohydrate-binding properties were analyzed, in addition to that of PPL2A, which was previously reported as a matrix protein. PPL3s and PPL4 shared only 35-50% homology to PPL2A, respectively; they exhibited significantly different carbohydrate-binding specificities based on the multiple glycan binding profiling data sets from frontal affinity chromatography analysis. The carbohydrate-binding specificity of PPL3s was similar to that of PPL2A, except only for Man3Fuc1Xyl1GlcNAc2 oligosaccharide, while PPL4 showed different carbohydrate-binding specificity compared with PPL2A and PPL3s. PPL2A and PPL3s mainly recognize agalactosylated- and galactosylated-type glycans. On the other hand, PPL4 binds to high-mannose-and hybrid-type N-linked glycans but not agalactosylated- and galactosylated-type glycans.


Assuntos
Lectinas/metabolismo , Pinctada/metabolismo , Lectinas de Plantas/metabolismo , Polissacarídeos/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Lectinas/química , Modelos Moleculares , Pinctada/química , Lectinas de Plantas/química , Polissacarídeos/química , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Alinhamento de Sequência
9.
Fish Shellfish Immunol ; 94: 72-80, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472263

RESUMO

In the present study, a sialic acid-binding lectin was cloned and characterized from Manila clam Ruditapes philippinarum (designed as RpSabl). The open reading frame of RpSabl encoded a polypeptide of 162 amino acids with a calculated molecular mass of 17.7 kDa. Analysis of the conserved domain suggested that RpSabl was a new member of the sialic acid-binding lectins family. In non-stimulated clams, RpSabl transcripts were constitutively expressed in all five tested tissues, especially in hepatopancreas. After Vibrio anguillarum challenge, the expression of RpSabl mRNA in hepatopancreas was significantly up-regulated at 3 h (3.8-fold, P < 0.05), 6 h (4.9-fold, P < 0.05), 12 h (12.3-fold, P < 0.01) and 24 h (9.7-fold, P < 0.01), while RpSabl transcripts in hemocytes was only significantly up-regulated at 6 h (8.5-Fold, P < 0.01). RNAi-mediated knockdown of RpSabl transcripts affected the survival rates of Manila clam against V. anguillarum, perhaps mainly due to the inhibited expression of antibacterial effectors (e.g. lysozyme and defensin). Moreover, recombinant protein of RpSabl (rRpSabl) possessed binding activities towards lipopolysaccharides (LPS), peptidoglycan (PGN) and glucan in vitro. Coinciding with the Pathogen-associated molecular patterns (PAMPs) binding assay, rRpSabl displayed broad bacterial-agglutination properties towards Vibrio harveyi, Vibrio splendidus, V. anguillarum, Enterobacter cloacae and Aeromonas hydrophila. Meanwhile, the phagocytosis and encapsulation ability of hemocytes could be significantly enhanced by rRpSabl incubation. All these results showed that RpSabl could function as a versatile molecule involved in the innate immune responses of R. philippinarum.


Assuntos
Antibacterianos/farmacologia , Bivalves/genética , Bivalves/imunologia , Lectinas/genética , Proteínas Opsonizantes/farmacologia , Ácidos Siálicos/metabolismo , Aeromonas hydrophila/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Enterobacter cloacae/efeitos dos fármacos , Lectinas/química , Lectinas/metabolismo , Alinhamento de Sequência , Vibrio/efeitos dos fármacos
10.
Chem Soc Rev ; 48(22): 5488-5505, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31552920

RESUMO

Glycans - simple or complex carbohydrates - play key roles as recognition determinants and modulators of numerous physiological and pathological processes. Thus, many biotechnological, diagnostic and therapeutic opportunities abound for molecular recognition entities that can bind glycans with high selectivity and affinity. This review begins with an overview of the current biologically and synthetically derived glycan-binding scaffolds that include antibodies, lectins, aptamers and boronic acid-based entities. It is followed by a more detailed discussion on various aspects of their generation, structure and recognition properties. It serves as the basis for highlighting recent key developments and technical challenges that must be overcome in order to fully deal with the specific recognition of a highly diverse and complex range of glycan structures.


Assuntos
Anticorpos/química , Aptâmeros de Nucleotídeos/química , Ácidos Borônicos/química , Lectinas/química , Polissacarídeos/química , Receptores Artificiais/química , Anticorpos/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Ácidos Borônicos/metabolismo , Humanos , Lectinas/metabolismo , Polissacarídeos/síntese química , Polissacarídeos/metabolismo , Receptores Artificiais/metabolismo
11.
BMC Res Notes ; 12(1): 607, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547886

RESUMO

OBJECTIVE: Research suggests human norovirus binding to histo-blood group antigen (HBGA)-like molecules on enteric bacteria may enhance viral pathogenesis; however, the properties of these bacterial ligands are not well known. Previous work identified, but did not characterize, seven norovirus-binding bacteria. To further examine this bacteria-virus binding interaction, enteric bacteria were analyzed via Western blot with anti-HBGA antibodies and lectins targeting HBGA-associated sugar components. Virus overlay assays using capsids from six different human norovirus strains further identified responsible ligands and strain dependent binding properties. RESULTS: Each bacterial species possessed varying degrees of HBGA-like activity, and lectin binding further elucidated potential sugar residues involved (N-acetyl-galactosamine, α-D-galactose or α-L-fucose). Both GI and GII norovirus capsids bound specific bacterial ligand sizes, and generally corresponded to anti-HBGA Western blot patterns. A 35-kDa band reacted with all HBGA antibodies, bound all six of the noroviruses tested, and had a high affinity for the lectins. Collectively, this work characterizes the varying carbohydrate residues potentially responsible for norovirus-bacteria interactions and provides a basis for future ligand identification.


Assuntos
Proteínas de Bactérias/metabolismo , Enterobacter cloacae/virologia , Interações Microbianas/genética , Norovirus/genética , Staphylococcus aureus/virologia , Acetilgalactosamina/química , Acetilgalactosamina/metabolismo , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/metabolismo , Bacillus/isolamento & purificação , Bacillus/virologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/genética , Antígenos de Grupos Sanguíneos/metabolismo , Western Blotting , Capsídeo/química , Capsídeo/metabolismo , Enterobacter cloacae/isolamento & purificação , Fucose/química , Fucose/metabolismo , Galactose/química , Galactose/metabolismo , Microbioma Gastrointestinal/genética , Expressão Gênica , Humanos , Klebsiella/isolamento & purificação , Klebsiella/virologia , Lectinas/química , Lectinas/metabolismo , Ligantes , Mimetismo Molecular , Norovirus/metabolismo , Ligação Proteica , Staphylococcus aureus/isolamento & purificação
12.
Int J Mol Sci ; 20(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31509989

RESUMO

Altered cell surface glycosylation in congenital and acquired diseases has been shown to affect cell differentiation and cellular responses to external signals. Hence, it may have an important role in immune regulation; however, T cell surface glycosylation has not been studied in systemic lupus erythematosus (SLE), a prototype of autoimmune diseases. Analysis of the glycosylation of T cells from patients suffering from SLE was performed by lectin-binding assay, flow cytometry, and quantitative real-time PCR. The results showed that resting SLE T cells presented an activated-like phenotype in terms of their glycosylation pattern. Additionally, activated SLE T cells bound significantly less galectin-1 (Gal-1), an important immunoregulatory lectin, while other lectins bound similarly to the controls. Differential lectin binding, specifically Gal-1, to SLE T cells was explained by the increased gene expression ratio of sialyltransferases and neuraminidase 1 (NEU1), particularly by elevated ST6 beta-galactosamide alpha-2,6-sialyltranferase 1 (ST6GAL1)/NEU1 and ST3 beta-galactoside alpha-2,3-sialyltransferase 6 (ST3GAL6)/NEU1 ratios. These findings indicated an increased terminal sialylation. Indeed, neuraminidase treatment of cells resulted in the increase of Gal-1 binding. Altered T cell surface glycosylation may predispose the cells to resistance to the immunoregulatory effects of Gal-1, and may thus contribute to the pathomechanism of SLE.


Assuntos
Galectina 1/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Ativação Linfocitária , Linfócitos T/metabolismo , Adulto , Antígenos CD/genética , Antígenos CD/metabolismo , Feminino , Expressão Gênica , Glicosilação , Humanos , Lectinas/metabolismo , Lúpus Eritematoso Sistêmico/genética , Masculino , Pessoa de Meia-Idade , Neuraminidase/genética , Neuraminidase/metabolismo , Sialiltransferases/genética , Sialiltransferases/metabolismo , Propriedades de Superfície , Adulto Jovem
13.
J Physiol Pharmacol ; 70(2)2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31443090

RESUMO

Omentin and vaspin are adipokines potentially considered in the development of liver pathology. Irisin is new myokin potentially participating in energy processes in the organisms. The aim of this study was to evaluate the plasma concentration of these cytokines and the relationships of them with selected parameters of laboratory tests and of histopathological changes in selected chronic liver diseases: non-alcoholic fatty liver diseases (NAFLD), primary biliary cholangitis (PBC) and alcoholic cirrhosis (AC). The plasma concentration of omentin was the highest in AC group and the lowest in control group (CG). Irisin plasma concentration was the highest in CG and the lowest in AC. Mean vaspin concentrations did not differ significantly between groups. Among many laboratory parameters, only in the AC group positive relationships were found between omentin concentration and bilirubin, as well as glucose, and negative between omentin level and the number of platelets and erythrocytes; there was a positive relationship between the concentration of vaspin and bilirubin, as well as negative between vaspin level and the number of erythrocytes or hematocrit value in this group. INR value had positive correlation with vaspin concentration and negative with irisin level in NAFLD group. No significant dependences between the concentrations of explored cytokines and laboratory tests were found in PBC group. It was found the positive correlation between the plasma concentration of irisin and fibrosis as well as inflammation in PBC group. The negative correlation between irisin level and inflammation in NAFLD was also showed. Omentin can be considered as an indicator for predicting inflammation, steatosis and balloon degeneration in NAFLD and PBC. Summarizing, it is unclear but possible that explored cytokines have some relationships with certain features of liver damage and development of chronic diseases of this organ.


Assuntos
Citocinas/metabolismo , Fibronectinas/metabolismo , Lectinas/metabolismo , Hepatopatias/metabolismo , Serpinas/metabolismo , Adulto , Idoso , Doença Crônica , Feminino , Proteínas Ligadas por GPI/metabolismo , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Chem Commun (Camb) ; 55(66): 9869-9872, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31364617

RESUMO

In this work, we designed and synthesized an aggregation-induced emission (AIE)-active tetraphenylethene-decorated pseudo-trisialic acid (TPE3S) and validated its high affinity for Siglecs using microscale thermophoresis techniques. TPE3S was a unique binding-on fluorescent trivalent sialocluster which was successfully utilized for the visualization of Siglecs expressed on the surface of mammalian cells.


Assuntos
Metabolismo dos Carboidratos , Lectinas/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Animais , Membrana Celular/metabolismo , Corantes Fluorescentes/química , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Células PC12 , Ligação Proteica , Ratos
15.
Fish Shellfish Immunol ; 94: 10-16, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465869

RESUMO

In crustaceans, it has been suggested that specific protection against pathogens could be triggered by vaccines and biological response modifiers; although the specific mechanisms of this protection have not been clarified yet. In the crayfish Cherax quadricarinatus, a humoral lectin (CqL) binds its own granular hemocytes through a specific receptor (CqLR) and increases the production of reactive oxygen species (ROS). In the present study, we challenged in vivo crayfishes with immunostimulants, ß-glucan (200 µg/kg) or LPS (20 µg/kg), and identified the participation of cellular and humoral mechanisms. The stimulants generated a complex modification in the total hemocytes count (THC), as well as in the proportion of hemocyte subsets. At 2 h after the challenge, the largest value in THC was observed in either challenged crayfishes. Furthermore, at the same time, hyaline hemocytes were the most abundant subset in the hemolymph; after 6 h, granular hemocytes (GH) were the most abundant hemocyte subset. It has been observed that a specific subset of GH possesses a CqLR that has been related to ROS production. After 2 and 6 h of the ß-glucan challenge, a significant increase in CqLR expression was observed in the three circulating hemocyte subsets; also, an increased expression of CqL was detected in a granular hemocytes sub-population. After 2 and 6 h of stimulation, the specific activity of the serum lectin challenged with ß-glucan was 250% and 160% higher than in the LPS-treated-group, respectively (P < 0.05). Hemocytes from challenged crayfishes were stimulated ex vivo with CqL, ROS production was 180% higher in hemocytes treated with ß-glucan + CqL than in hemocytes treated with LPS + CqL (P < 0.05). The results evidence the effectivity of immune stimulators to activate specific crayfish defense mechanisms, the participation of CqL and its receptor (CqLR) could play an important role in the regulation of immune cellular functions, like ROS production, in Cherax quadricarinatus.


Assuntos
Astacoidea/genética , Astacoidea/imunologia , Expressão Gênica/efeitos dos fármacos , Imunidade Celular/genética , Imunidade Humoral/genética , Lectinas/genética , Receptores Mitogênicos/genética , Adjuvantes Imunológicos/farmacologia , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Astacoidea/efeitos dos fármacos , Hemócitos , Hemolinfa/metabolismo , Lectinas/metabolismo , Lipopolissacarídeos/farmacologia , Receptores Mitogênicos/metabolismo , beta-Glucanas/farmacologia
16.
Molecules ; 24(16)2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31443278

RESUMO

For the effective discovery of the biological roles and disease-specific alterations concerning protein glycosylation in tissue samples, it is important to know beforehand the quantitative and qualitative variations of glycan structures expressed in various types of cells, sites, and tissues. To this end, we used laser microdissection-assisted lectin microarray (LMA) to establish a simple and reproducible method for high-throughput and in-depth glycomic profiling of formalin-fixed paraffin-embedded tissue sections. Using this "tissue glycome mapping" approach, we present 234 glycomic profiling data obtained from nine tissue sections (pancreas, heart, lung, thymus, gallbladder, stomach, small intestine, colon, and skin) of two 8-week-old male C57BL/6J mice. We provided this LMA-based dataset in the similar interface as that of GlycomeAtlas, a previously developed tool for mass spectrometry-based tissue glycomic profiling, allowing easy comparison of the two types of data. This online tool, called "LM-GlycomeAtlas", allows users to visualize the LMA-based tissue glycomic profiling data associated with the sample information as an atlas. Since the present dataset allows the comparison of glycomic profiles, it will facilitate the evaluation of site- and tissue-specific glycosylation patterns. Taking advantage of its extensibility, this tool will continue to be updated with the expansion of deposited data.


Assuntos
Glicômica , Lectinas/metabolismo , Análise Serial de Proteínas , Software , Interface Usuário-Computador , Animais , Glicômica/métodos , Glicosilação , Masculino , Camundongos , Microdissecção , Especificidade de Órgãos , Análise Serial de Proteínas/métodos
17.
Glycoconj J ; 36(4): 241-257, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31267247

RESUMO

We have explored the fundamental biological processes by which complex carbohydrates expressed on cellular glycoproteins and glycolipids and in secretions of cells promote cell adhesion and signaling. We have also explored processes by which animal pathogens, such as viruses, bacteria, and parasites adhere to glycans of animal cells and initiate disease. Glycans important in cell signaling and adhesion, such as key O-glycans, are essential for proper animal development and cellular differentiation, but they are also involved in many pathogenic processes, including inflammation, tumorigenesis and metastasis, and microbial and parasitic pathogenesis. The overall hypothesis guiding these studies is that glycoconjugates are recognized and bound by a growing class of proteins called glycan-binding proteins (GBPs or lectins) expressed by all types of cells. There is an incredible variety and diversity of GBPs in animal cells involved in binding N- and O-glycans, glycosphingolipids, and proteoglycan/glycosaminoglycans. We have specifically studied such molecular determinants recognized by selectins, galectins, and many other C-type lectins, involved in leukocyte recruitment to sites of inflammation in human tissues, lymphocyte trafficking, adhesion of human viruses to human cells, structure and immunogenicity of glycoproteins on the surfaces of human parasites. We have also explored the molecular basis of glycoconjugate biosynthesis by exploring the enzymes and molecular chaperones required for correct protein glycosylation. From these studies opportunities for translational biology have arisen, involving production of function-blocking antibodies, anti-glycan specific antibodies, and synthetic glycoconjugates, e.g. glycosulfopeptides, that specifically are recognized by GBPs. This invited short review is based in part on my presentation for the IGO Award 2019 given by the International Glycoconjugate Organization in Milan.


Assuntos
Adesão Celular/fisiologia , Açúcares/metabolismo , Animais , Galactosiltransferases/metabolismo , Glicoconjugados/metabolismo , Glicômica/métodos , Glicoproteínas/metabolismo , Glicosilação , Humanos , Inflamação/metabolismo , Lectinas/metabolismo , Polissacarídeos/metabolismo , Transdução de Sinais/fisiologia
18.
Molecules ; 24(13)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277476

RESUMO

Advanced glycation end products (AGE), the most known aging biomarker, may cause "inflamm-aging" (i.e., chronic low-grade inflammation that develops with aging) in both aged and diabetes groups. However, the molecular bases of inflamm-aging remain obscure. We prepared AGE by incubating BSA (0.0746 mmol/L) + glucose (0.5 mol/L) at 37 °C in 5% CO2-95% air for 1-180 days. The lysine glycation in BSA-AGE reached 77% on day 30 and 100% after day 130, whereas the glycation of arginine and cysteine was minimal. The Nε-(carboxymethyl)-lysine content in BSA-AGE was also increased with increasing number of incubation days. The lectin-binding assay revealed that the glycation of BSA not only altered the conformational structure, but lost binding capacity with various lectins. An immunological functional assay showed that BSA-AGE > 8 µg/mL significantly suppressed normal human Th1 (IL-2 and IFN-γ) and Th2 (IL-10) mRNA expression, whereas AGE > 0.5 µg/mL enhanced monocyte IL-6 production irrelevant to cell apoptosis. The AGE-enhanced monocyte IL-6 production was via MAPK-ERK and MyD88-transduced NF-κBp50 signaling pathways. To elucidate the structure-function relationship of BSA-AGE-enhanced IL-6 production, we pre-preincubated BSA-AGE with different carbohydrate-degrading, protein-degrading, and glycoprotein-degrading enzymes. We found that trypsin and carboxypeptidase Y suppressed whereas ß-galactosidase enhanced monocyte IL-6 production. In conclusion, BSA-AGE exerted both immunosuppressive and pro-inflammatory effects that are the molecular basis of inflamm-aging in aged and diabetes groups.


Assuntos
Produtos Finais de Glicação Avançada/farmacologia , Interleucina-6/genética , Sistema de Sinalização das MAP Quinases , Monócitos/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Soroalbumina Bovina/farmacologia , Linfócitos T Auxiliares-Indutores/metabolismo , Aminoácidos/metabolismo , Animais , Bovinos , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoproteínas/metabolismo , Humanos , Interleucina-6/metabolismo , Lectinas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Reação de Maillard/efeitos dos fármacos , Peso Molecular , Monócitos/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/metabolismo
19.
Mediators Inflamm ; 2019: 9086758, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360120

RESUMO

Macrophages contribute to a continuous increase in blood pressure and kidney damage in hypertension, but their polarization status and the underlying mechanisms have not been clarified. This study revealed an important role for M2 macrophages and the YM1/Chi3l3 protein in hypertensive nephropathy in a mouse model of hypertension. Bone marrow cells were isolated from the femurs and tibia of male FVB/N (control) and transgenic hypertensive animals that overexpressed the rat form of angiotensinogen (TGM(rAOGEN)123, TGM123-FVB/N). The cells were treated with murine M-CSF and subsequently with LPS+IFN-γ to promote their polarization into M1 macrophages and IL-4+IL-13 to trigger the M2 phenotype. We examined the kidneys of TGM123-FVB/N animals to assess macrophage polarization and end-organ damage. mRNA expression was evaluated using real-time PCR, and protein levels were assessed through ELISA, CBA, Western blot, and immunofluorescence. Histology confirmed high levels of renal collagen. Cells stimulated with LPS+IFN-γ in vitro showed no significant difference in the expression of CD86, an M1 marker, compared to cells from the controls or the hypertensive mice. When stimulated with IL-4+IL-13, however, macrophages of the hypertensive group showed a significant increase in CD206 expression, an M2 marker. The M2/M1 ratio reached 288%. Our results indicate that when stimulated in vitro, macrophages from hypertensive mice are predisposed toward polarization to an M2 phenotype. These data support results from the kidneys where we found an increased infiltration of macrophages predominantly polarized to M2 associated with high levels of YM1/Chi3l3 (91,89%), suggesting that YM1/Chi3l3 may be a biomarker of hypertensive nephropathy.


Assuntos
Hipertensão/metabolismo , Nefropatias/metabolismo , Lectinas/metabolismo , Macrófagos/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo , Animais , Biomarcadores/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Rim/metabolismo , Nefropatias/genética , Lectinas/genética , Ativação de Macrófagos/fisiologia , Masculino , Camundongos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , beta-N-Acetil-Hexosaminidases/genética
20.
Mar Drugs ; 17(6)2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31207891

RESUMO

More than 80% of infectious bacteria form biofilm, which is a bacterial cell community surrounded by secreted polysaccharides, proteins and glycolipids. Such bacterial superstructure increases resistance to antimicrobials and host defenses. Thus, to control these biofilm-forming pathogenic bacteria requires antimicrobial agents with novel mechanisms or properties. Pseudomonas aeruginosa, a Gram-negative opportunistic nosocomial pathogen, is a model strain to study biofilm development and correlation between biofilm formation and infection. In this study, a recombinant hemolymph plasma lectin (rHPLOE) cloned from Taiwanese Tachypleus tridentatus was expressed in an Escherichia coli system. This rHPLOE was shown to have the following properties: (1) Binding to P. aeruginosa PA14 biofilm through a unique molecular interaction with rhamnose-containing moieties on bacteria, leading to reduction of extracellular di-rhamnolipid (a biofilm regulator); (2) decreasing downstream quorum sensing factors, and inhibiting biofilm formation; (3) dispersing the mature biofilm of P. aeruginosa PA14 to improve the efficacies of antibiotics; (4) reducing P. aeruginosa PA14 cytotoxicity to human lung epithelial cells in vitro and (5) inhibiting P. aeruginosa PA14 infection of zebrafish embryos in vivo. Taken together, rHPLOE serves as an anti-biofilm agent with a novel mechanism of recognizing rhamnose moieties in lipopolysaccharides, di-rhamnolipid and structural polysaccharides (Psl) in biofilms. Thus rHPLOE links glycan-recognition to novel anti-biofilm strategies against pathogenic bacteria.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Ramnose/metabolismo , Células A549 , Animais , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/efeitos dos fármacos , Escherichia coli/metabolismo , Glicolipídeos/metabolismo , Caranguejos Ferradura/metabolismo , Humanos , Lectinas/metabolismo , Polissacarídeos Bacterianos/metabolismo , Percepção de Quorum/efeitos dos fármacos , Peixe-Zebra
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