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1.
J Comp Pathol ; 210: 29-37, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552538

RESUMO

Neospora caninum is an obligate intracellular parasite that causes abortion in ruminants. Different strains produce differences in the severity of disease outcomes. These differences may cause physiological or pathological changes in cells, modifying the intercellular interactions and intracellular transport pathways that could be evidenced by identifying the terminal sugars. This study aimed to characterize the oligosaccharide pattern in the bovine placenta and uterus after infection with tachyzoites of three different strains of N. caninum (Nc-1, Nc-6 Argentina and Nc Spain-7) during early gestation. Fourteen heifers were inoculated intravenously on day 70 of gestation with 2 × 108 N. caninum tachyzoites and samples of placentae and uteri were analysed by histology and lectin histochemistry. In the infected groups, severe placentitis was associated with changes in lectin binding in the vascular endothelium by Lens culinaris agglutinin (LCA), Pisum sativum agglutinin (PSA) and Ricinus communis I (RCA-I) lectins, in the epithelial cells of the endometrial glands by RCA-I, Dolichos biflorus agglutinin (DBA), succinylated wheat germ agglutinin, peanut agglutinin (PNA), concanavalin-A (CON-A), LCA, PSA and Phaseolus vulgaris erythroagglutinin (PHA-e), and in the trophoblast layer by PNA, CON-A, LCA, PSA, PHA-e, soybean agglutinin, RCA-I, DBA and Bandieraea simplicifolia agglutinin (BSA-I). The results suggest that N. caninum causes changes in the glycosylation pattern in the maternofetal interface tissues and might cause abortions in early gestation due to changes in the cellular structure of the placenta.


Assuntos
Neospora , Gravidez , Bovinos , Animais , Feminino , Neospora/metabolismo , Glicosilação , Lectinas , Placenta/metabolismo , Útero/metabolismo , Aglutininas/metabolismo
2.
Protein J ; 43(2): 283-297, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38265733

RESUMO

Scavenger receptors are a protein superfamily that typically consists of one or more repeats of the scavenger receptor cysteine-rich structural domain (SRCRD), which is an ancient and highly conserved protein module. The expression and purification of eukaryotic proteins containing multiple disulfide bonds has always been challenging. The expression systems that are commonly used to express SRCRD proteins mainly consist of eukaryotic protein expression systems. Herein, we established a high-level expression strategy of a Type B SRCRD unit from human salivary agglutinin using the Escherichia coli expression system, followed by a refolding and purification process. The untagged recombinant SRCRD was expressed in E. coli using the pET-32a vector, which was followed by a refolding process using the GSH/GSSG redox system. The SRCRD expressed in E. coli SHuffle T7 showed better solubility after refolding than that expressed in E. coli BL21(DE3), suggesting the importance of the disulfide bond content prior to refolding. The quality of the refolded protein was finally assessed using crystallization and crystal structure analysis. As proteins refolded from inclusion bodies exhibit a high crystal quality and reproducibility, this method is considered a reliable strategy for SRCRD protein expression and purification. To further confirm the structural integrity of the refolded SRCRD protein, the purified protein was subjected to crystallization using sitting-drop vapor diffusion method. The obtained crystals of SRCRD diffracted X-rays to a resolution of 1.47 Å. The solved crystal structure appeared to be highly conserved, with four disulfide bonds appropriately formed. The surface charge distribution of homologous SRCRD proteins indicates that the negatively charged region at the surface is associated with their calcium-dependent ligand recognition. These results suggest that a high-quality SRCRD protein expressed by E. coli SHuffle T7 can be successfully folded and purified, providing new options for the expression of members of the scavenger receptor superfamily.


Assuntos
Escherichia coli , Redobramento de Proteína , Proteínas Recombinantes , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Cristalografia por Raios X , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Cristalização , Aglutininas/química , Aglutininas/genética , Aglutininas/metabolismo , Domínios Proteicos , Expressão Gênica , Modelos Moleculares , Cisteína/química , Cisteína/genética , Receptores Depuradores/química , Receptores Depuradores/genética , Receptores Depuradores/metabolismo
3.
BMC Vet Res ; 19(1): 187, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789311

RESUMO

BACKGROUND: Avian Escherichia coli (E.coli) type 1 fimbriae adhere to avian tracheal epithelial cells through the FimH protein. However, the adhesion-related antigen is still unknown. The purpose of this study was to analyze the antigenicity of the type 1 fimbrial FimH protein of wild-type avian E. coli, screen antigen epitopes, and prepare monoclonal antibodies (mAbs) that can block the adhesion of avian E. coli. RESULTS: In this study, the nucleic acid homologies of MG2 (O11), TS12 (O18), and YR5 (O78) with K12 were 97.7%, 99.6%, and 97.7%, respectively, and the amino acid sequence similarity reached 98.7%, 99.3%, and 98.0%, respectively. The epitopes and hydrophilicities of the FimH proteins of these three strains were similar. The more obvious lectin domain epitopes were located at FimH protein positions 111-124 and 154-162. The mAbs 7C2 and 7D8 against these two epitopes were prepared. An adhesion inhibition test showed that 7C2 and 7D8 blocked bacterial adhesion to avian tracheal epithelial cells. The mAb 7C2 against the 111-124 epitope inhibited O78 strain adhesion by 93%, and the mAb 7D8 against the 154-162 epitope inhibited O78 strain adhesion by 49%, indicating that these two epitopes are closely related to the adhesion of type 1 fimbriae. However, only the 111-124 epitope-recognizing mAb 7C2 inhibited bacterial agglutination of erythrocytes, indicating that host cell receptor binding and erythrocyte agglutination are not mediated by the same spatial locations within the FimH protein. CONCLUSIONS: The results demonstrate that the mAbs 7C2 and 7D8 against FimH protein positions 111-124 and 154-162 could inhibit the adhesion of E.coli to the chicken trachea.


Assuntos
Escherichia coli , Proteínas de Fímbrias , Animais , Escherichia coli/genética , Proteínas de Fímbrias/genética , Epitopos/metabolismo , Adesinas de Escherichia coli/genética , Adesinas de Escherichia coli/química , Aglutininas/metabolismo , Aderência Bacteriana
4.
Tissue Cell ; 82: 102074, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36948081

RESUMO

INTRODUCTION: Recent investigations suggest the potential negative impact of SARS-CoV-2 infection on pregnant women and pregnancy outcome. In addition, some studies have described pathological changes in the placental tissue of SARS-CoV-2-positive mothers, which are related or not to the infection severity and/or infection trimester. Among the various molecules involved in the normal structure and functionality of the placenta, sialic acids (Sias) seem to play an important role. Hence, we aimed to investigate possible changes in the distribution and content of Sias with different glycosidic linkages, namely α2,3 and α2,6 Galactose- or N-acetyl-Galactosamine-linked Sias and polymeric Sia (PolySia), in placentas from pregnant women infected by SARS-CoV-2 during the three different pregnancy trimesters. METHODS: α2,3 and α2,6 Galactose-linked Sias were evaluated by lectin histochemistry (Maackia amurensis agglutinin (MAA) and Sambucus nigra agglutinin (SNA), respectively), while immunohistochemistry was used for PolySia detection. RESULTS: Data showed lower levels of α2,3 Galactose-linked Sias in the trophoblast and underlying basement membrane/basal plasma membrane in placentas from women infected during the second and third infection trimester compared with uninfected cases and those infected during first trimester. On the other hand, higher levels of PolySia were detected in the trophoblast during the second and third infection trimester. CONCLUSIONS: Our findings suggest that changes in the sialylation status of trophoblast and its basement membrane/basal plasma membrane, together with other concomitant factors, could be at the basis of the most common placental histopathological alterations and gestational complications found especially in pregnancies with SARS-CoV-2 infection during the second and third trimester.


Assuntos
COVID-19 , Placenta , Gravidez , Feminino , Humanos , Placenta/metabolismo , COVID-19/patologia , SARS-CoV-2 , Galactose/metabolismo , Aglutininas/metabolismo
5.
Transplantation ; 107(6): 1291-1301, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367925

RESUMO

BACKGROUND: Organ allograft rejection is mainly driven by T-cell response. Studies have shown that fucosylation plays essential roles in the immune cell development and function. Terminal fucosylation inhibitor, 2-deoxy-D-galactose (2-D-gal), has been reported to suppress immunoresponse of macrophages, but its effects on T-cell-mediated immune response and transplant rejection have not been fully explored. METHODS: The terminal fucosylation level in T cells was detected through ulex europaeus agglutinin-I staining. The consequences of 2-D-gal on murine T-cell proliferation, activation, cytokine secretion, and cell cycle were investigated in vitro. T-cell receptor signaling cascades were examined. Last, mouse skin transplant model was utilized to evaluate the regulatory effects of 2-D-gal on T-cell response in vivo. RESULTS: The expression of fucosyltransferase1 was upregulated in CD3/CD28-activated T cells along with an elevation of α(1,2)-fucosylation level as seen by ulex europaeus agglutinin-I staining. Furthermore, 2-D-gal suppressed T-cell activation and proliferation, decrease cytokines production, arrest cell cycle, and prevent the activation of T-cell receptor signaling cascades. In vivo experiments showed that 2-D-gal limited T-cell proliferation to prolong skin allograft in mice. This was accompanied by lower level of inflammatory cytokines, and were comparable to those treated with Cyclosporin A. CONCLUSIONS: Terminal fucosylation appears to play a role in T-cell activation and proliferation, and its inhibitor, 2-D-gal, can suppress T-cell activation and proliferation both in vitro and in vivo. In a therapeutic context, inhibiting terminal fucosylation may be a potential strategy to prevent allogeneic transplant rejection.


Assuntos
Transplante de Pele , Linfócitos T , Camundongos , Animais , Linfócitos T/metabolismo , Modelos Animais de Doenças , Citocinas/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Aglutininas/metabolismo
6.
Cytokine ; 160: 156022, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099756

RESUMO

Although conventional knockout and transgenic mouse models have significantly advanced our understanding of Receptor Activator of NF-κB Ligand (RANKL) signaling in intra-thymic crosstalk that establishes self-tolerance and later stages of lymphopoiesis, the unique advantages of conditional mouse transgenesis have yet to be explored. A main advantage of conditional transgenesis is the ability to express a transgene in a spatiotemporal restricted manner, enabling the induction (or de-induction) of transgene expression during predetermined stages of embryogenesis or during defined postnatal developmental or physiological states, such as puberty, adulthood, and pregnancy. Here, we describe the K5: RANKL bigenic mouse, in which transgene derived RANKL expression is induced by doxycycline and targeted to cytokeratin 5 positive medullary thymic epithelial cells (mTECs). Short-term doxycycline induction reveals that RANKL transgene expression is significantly induced in the thymic medulla and only in response to doxycycline. Prolonged doxycycline induction in the K5: RANKL bigenic results in a significantly enlarged thymus in which mTECs are hyperproliferative. Flow cytometry showed that there is a marked enrichment of CD4+ and CD8+ single positive thymocytes with a concomitant depletion of CD4+ CD8+ double positives. Furthermore, there is an increase in the number of FOXP3+ T regulatory (Treg) cells and Ulex Europaeus Agglutinin 1+ (UEA1+) mTECs. Transcriptomics revealed that a remarkable array of signals-cytokines, chemokines, growth factors, transcription factors, and morphogens-are governed by RANKL and drive in part the K5: RANKL thymic phenotype. Extended doxycycline administration to 6-weeks results in a K5: RANKL thymus that begins to display distinct histopathological features, such as medullary epithelial hyperplasia, extensive immune cell infiltration, and central tissue necrosis. As there are intense efforts to develop clinical approaches to restore thymic medullary function in the adult to treat immunopathological conditions in which immune cell function is compromised following cancer therapy or toxin exposure, an improved molecular understanding of RANKL's involvement in thymic medulla enlargement will be required. We believe the versatility of the conditional K5: RANKL mouse represents a tractable model system to assist in addressing this requirement as well as many other questions related to RANKL's role in thymic normal physiology and disease processes.


Assuntos
Doxiciclina , Ligante RANK/metabolismo , Transcriptoma , Aglutininas/metabolismo , Animais , Citocinas/metabolismo , Doxiciclina/farmacologia , Células Epiteliais/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Queratina-5/genética , Queratina-5/metabolismo , Ligantes , Camundongos , Camundongos Transgênicos , NF-kappa B/metabolismo , Fenótipo , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Timo/metabolismo
7.
F1000Res ; 11: 557, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112976

RESUMO

Background: A relationship between oral microbiota and susceptibility to SARS-CoV-2 infection has been extensively studied. However, the relationship between oral commensal flora and expression of angiotensin-converting enzyme 2 ( ACE2) remains to be established. In this observational study, we collected saliva from patients with COVID-19 and evaluated the relationship between ACE2 expression and Candida albicans as well as with selected gram-negative bacteria ( Aggregatibacter actin o mycetemcomitans, Fusobacterium nucleatum, and Veillonella parvula). We investigated how this may be directly or indirectly involved in oral dysbiosis in patients with COVID-19. Methods: We included 23 hospitalized patients admitted to Universitas Indonesia Hospital with PCR-confirmed COVID-19, with six healthy participants serving as controls. Saliva and tongue surface swabs were collected from patients with diabetes (DG) and without diabetes (NDG) and subject controls. Using quantitative PCR (qPCR) we assessed the mRNA expression of ACE2, the abundance of C. albicans, and the transcription levels of its biofilm-associated genes, agglutinin-like protein 3 ( ALS3), hyphal wall protein 1 ( HWP1), and yeast-form wall protein 1 ( YWP1). We also counted the relative proportion of the three selected gram-negative oral bacteria in saliva. All analyses were performed to determine the relationship between ACE2 expression and C. albicans and gram-negative bacteria. Results: ACE2 mRNA expression was significantly higher in tongue swab samples than in saliva. However, no significant difference was observed between the patient groups. Conversely, DG patients had a significantly higher abundance of C. albicans in saliva compared to NDG patients and control group patients. The correlation and sensitivity/specificity relationship between ACE2 expression and C. albicans or the selected oral bacteria were also observed. Conclusions: The data show that ACE2 expression can be detected in saliva of patients with COVID-19 and its association with C. albicans and gram-negative oral bacteria might contribute toward developing an oral dysbiosis based predictor for prognosis of COVID-19 severity.


Assuntos
COVID-19 , Candida albicans , Actinas , Aglutininas/metabolismo , Aggregatibacter actinomycetemcomitans , Enzima de Conversão de Angiotensina 2 , Disbiose , Humanos , RNA Mensageiro/metabolismo , SARS-CoV-2 , Saliva/microbiologia
8.
Nat Commun ; 13(1): 2463, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513379

RESUMO

Candida albicans is the most common fungal pathogen and a prevalent cause of deadly bloodstream infections. Better understanding of the immune response against it, and the ways by which it evades immunity, are crucial for developing new therapeutics against it. Natural Killer (NK) cells are innate lymphocytes best known for their role against viruses and tumors. In recent years it became clear that NK cells also play an important role in anti-fungal immunity. Here we show that while NK cells recognize and eliminate C. albicans, the fungal cells inhibit NK cells by manipulating the immune checkpoint receptor TIGIT (T cell immunoreceptor with Ig and ITIM domains) in both humans and mice. We identify the responsible fungal ligands as members of the Als (Agglutinin-Like Sequences) protein family. Furthermore, we show that blocking this interaction using immunotherapy with a TIGIT-blocking antibody can re-establish anti-Candida immunity and serve as a potential therapeutic tool.


Assuntos
Aglutininas , Candida albicans , Aglutininas/metabolismo , Animais , Candida albicans/metabolismo , Imunoterapia , Células Matadoras Naturais , Camundongos , Receptores Imunológicos/metabolismo
9.
Turk J Gastroenterol ; 33(2): 88-94, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35238778

RESUMO

BACKGROUND: Glycosylation is a common post-translational modification, and it has been reported that alterations in the glycosylation patterns on cells are related to cell proliferation, differentiation, tissue adhesion, and carcinogenesis. This study aimed to investigate the relationship between Helicobacter pylori infection and gastric mucosal glycosylation using a lectin microarray system. METHODS: Gastric mucosal samples were obtained from 10 Helicobacter pylori-non-infected patients, 10 H. pylori-infected patients, and 10 after H. pylori-eradicated patients who underwent gastric mucosal biopsy by endoscopy in our institute. The gastric gland cells which were isolated from formalin-fixed, paraffin-embedded gastric mucosal biopsy samples using laser capture microdissection were used for lectin microarray to obtain lectin-glycan interaction values. RESULTS: Comparison of the lectin-glycan interaction values before and after eradication in the same patients showed significant increases for Ricinus communis agglutinin 120, Trichosanthes japonica agglutinin II, Euonymus europaeus lectin, jacalin, Amaranthus caudatus agglutinin, and Maclura pomifera agglutinin and significant decreases for Urtica dioica agglutinin, Lycopersicon esculentum lectin, Ulex europaeus agglutinin, Sambucus nigra agglutinin, Sambucus sieboldiana agglutinin, and Trichosanthes japonica agglutinin I. Furthermore, jacalin and MPA in the gastric antrum were significantly decreased with H. pylori infection compared with the without infection group and improved to the levels seen without infection as a result of eradication. Lycopersicon esculentum lectin, Sambucus nigra agglutinin, Sambucus sieboldiana agglutinin, and Trichosanthes japonica agglutinin I in the gastric body were significantly increased with H. pylori infection and improved to the level seen without infection as a result of eradication. CONCLUSION: H. pylori infection changes the lectin binding state which is related to various cancers on the gastric mucosal cell. Furthermore, those changes are reversible by H. pylori eradication.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Aglutininas/metabolismo , Mucosa Gástrica/patologia , Glicosilação , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/patologia , Humanos , Lectinas/metabolismo , Análise em Microsséries , Polissacarídeos/metabolismo
10.
Chembiochem ; 23(4): e202100388, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34490706

RESUMO

We have designed and synthesized six different multivalent electrophiles as carbohydrate affinity labeling probes. Evaluation of the reactivity of the electrophiles against peanut agglutinin (PNA) and Ricinus communis agglutinin (RCA) showed that p- and m-aryl sulfonyl fluoride are effective protein reactive groups that label carbohydrate binding lectins in a ligand-dependent fashion at a nanomolar probe concentration. Analysis of the selectivity of affinity labeling in the presence of excess BSA as a nonspecific protein indicated that m-arylsulfonyl fluoride is a more selective protein-reactive group, albeit with attenuated reactivity. Further analysis showed that the labeling efficiency of the multivalent electrophilic probes can be improved by employing reaction conditions involving 25 °C instead of typically employed 4 °C. Both isomers of arylsulfonyl fluoride groups together represent promising affinity labels for target identification studies that could serve as more efficient alternatives to photoreactive groups.


Assuntos
Lectinas/análise , Ácidos Sulfínicos/química , Aglutininas/metabolismo , Estrutura Molecular , Aglutinina de Amendoim/química , Ricinus/química , Ácidos Sulfínicos/síntese química , Ácidos Sulfínicos/farmacologia
11.
Molecules ; 26(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066878

RESUMO

Plant lectins are widely used in medical glycosciences and glycotechnology. Many lectin-based techniques have been applied for the detection of disease-associated glycans and glycoconjugates. In this study, Butea monosperma agglutinin (BMA), a lectin purified from seeds of the medicinal plant Butea monosperma, was used for the detection of cholangiocarcinoma (CCA)-associated glycans. Expression of BMA-binding N-acetyl galactosamine/galactose (GalNAc/Gal)-associated glycan (BMAG) in CCA tissues was determined using BMA lectin histochemistry; the results showed that BMAG was undetectable in normal bile ducts and drastically increased in preneoplastic bile ducts and CCA. The study in hamsters showed that an increase of BMAG was associated with carcinogenesis of CCA. Using an in-house double BMA sandwich enzyme-linked lectin assay, BMAG was highly detected in the sera of CCA patients. The level of serum BMAG in CCA patients (N = 83) was significantly higher than non-CCA controls (N = 287) and it was applicable for diagnosis of CCA with 55.4% sensitivity, 81.9% specificity, and 76.0% accuracy. A high level of serum BMAG (≥82.5 AU/mL) was associated with unfavorable survival of CCA patients; this information suggested the potential of serum BMAG as a poor prognostic indicator of CCA. In summary, BMAG was aberrantly expressed in preneoplastic bile ducts and CCA, it was also highly detected in patient serum which potentially used as a marker for diagnosis and prognostic prediction of CCA.


Assuntos
Aglutininas/metabolismo , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/diagnóstico , Butea/química , Colangiocarcinoma/sangue , Colangiocarcinoma/diagnóstico , Extratos Vegetais/metabolismo , Lectinas de Plantas/metabolismo , Polissacarídeos/metabolismo , Animais , Neoplasias dos Ductos Biliares/patologia , Biomarcadores Tumorais/sangue , Colangiocarcinoma/patologia , Cricetinae , Modelos Animais de Doenças , Feminino , Histocitoquímica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Plantas Medicinais/química , Prognóstico , Sementes/química
12.
Anal Chem ; 92(20): 14012-14020, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32936606

RESUMO

Glycans attached to lipids and membrane-bound and secreted proteins and peptides mediate many important physiological and pathophysiological processes through interactions with glycan-binding proteins (GBPs). However, uncovering functional glycan ligands is challenging due to the large number of naturally occurring glycan structures, the limited availability of glycans in their purified form, the low affinities of GBP-glycan interactions, and limitations in existing binding assays. This work explores the application of catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) for screening libraries of N-glycans derived from natural sources. The assay was tested by screening a small-defined library of complex N-glycans at equimolar concentrations against plant and human GBPs with known specificities for either α2-3- or α2-6-linked sialosides, with affinities in the millimolar to micromolar range. Validation experiments, performed in negative ion mode, revealed that bound N-glycan ligands are readily released, as intact deprotonated ions, from GBPs in the gas phase using collision-induced dissociation. Moreover, the relative abundances of the released ligands closely match their solution affinities. The results obtained for a natural N-glycan library produced from cultured immune cells serve to highlight the ease with which CaR-ESI-MS can screen complex mixtures of N-glycans for interactions. Additionally, scaling the relative abundances of released glycan ligands according to their relative abundances in solution, as determined by hydrophilic interaction-ultrahigh-performance liquid chromatography of the fluorescently labeled library, allows the relative affinities of glycan ligands to be ranked.


Assuntos
Glicômica/métodos , Polissacarídeos/análise , Espectrometria de Massas por Ionização por Electrospray , Aglutininas/química , Aglutininas/metabolismo , Cromatografia Líquida de Alta Pressão , Humanos , Ligantes , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Polissacarídeos/metabolismo , Ligação Proteica , Sambucus nigra/metabolismo , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/química , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo
13.
Eur J Histochem ; 64(3)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32613817

RESUMO

Lectin histochemistry (LHC) and immunohistochemistry (IHC), which demonstrate the composition and localisation of sugar residues and proteins in cell membranes, respectively, are generally used separately. Using these two methods, we previously demonstrated that malignant transformation of urothelial cells results in the alterations of protein glycosylation and reduced expression of urothelium-specific integral membrane proteins uroplakins (UPs). However, the correlation between these changes was not studied yet. To evaluate this correlation, we developed innovative method, which we named combined lectin- and immuno- histochemistry (CLIH). We used human biopsies of 6 normal urothelia and 9 papillary urothelial carcinomas, i.e. 3 papillary urothelial neoplasms of low malignant potential (PUNLMP), 3 non-invasive papillary urothelial carcinomas of low grade (pTa, l.g.), and 3 invasive papillary urothelial carcinomas of high grade (pT1, h.g.). We tested five different protocols (numbered 1-5) of CLIH on paraffin and cryo-semithin sections and compared them with LHC and IHC performed separately. Additionally, we carried out western and lectin blotting with antibodies against UPs and lectins Amaranthus caudatus agglutinin (ACA), Datura stramonium agglutinin (DSA), and jacalin, respectively. We showed that incubation with primary antibodies first, followed by the mixture of secondary antibodies and lectins is the most efficient CLIH method (protocol number 5). Additionally, 300 nm thick cryo-semithin sections enabled better resolution of co-localisation between sugar residues and proteins than 5 µm thick paraffin sections. In the normal urothelium, CLIH showed co-localisation of lectins ACA and jacalin with UPs in the apical plasma membrane (PM) of superficial umbrella cells. In papillary urothelial carcinomas, all three lectins (ACA, DSA and jacalin) labelled regions of apical PM, where they occasionally co-localised with UPs. Western and lectin blotting confirmed the differences between normal urothelium and papillary urothelial carcinomas. Our results show that CLIH, when used with various sets of lectins and antigens, is a useful, quick, and reliable method that could be applied for basic cell biology research as well as detailed subtyping of human urothelial carcinomas.


Assuntos
Carcinoma Papilar/diagnóstico por imagem , Células Epiteliais/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Aglutininas/metabolismo , Amaranthus/química , Animais , Anticorpos/imunologia , Artocarpus/química , Bovinos , Datura stramonium/química , Corantes Fluorescentes/química , Cabras , Humanos , Imuno-Histoquímica , Microscopia de Fluorescência , Lectinas de Plantas/metabolismo , Coelhos , Rodaminas/química , Ácidos Sulfônicos/química , Bexiga Urinária/patologia , Uroplaquinas/imunologia , Uroplaquinas/metabolismo , Urotélio/metabolismo , Urotélio/patologia
14.
Turk J Med Sci ; 50(4): 1028-1037, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-31655502

RESUMO

Background/aim: We aimed to explore the roles of glycoprotein glycosylation in the pathogenesis of Kashin­Beck disease (KBD), and evaluated the effectiveness of sodium hyaluronate treatment. Materials and methods: Blood and saliva were collected from KBD patients before and after the injection of sodium hyaluronate. Normal healthy subjects were included as controls. Saliva and serum lectin microarrays and saliva and serum microarray verifications were used to screen and confirm the differences in lectin levels among the three groups. Results: In saliva lectin microarray, bindings to Sophora japonica agglutinin (SJA), Griffonia (Bandeiraea) simplicifolia lectin I (GSL-I), Euonymus europaeus lectin (EEL), Maackia amurensis lectin II (MAL-II), Sambucus nigra lectin (SNA), Hippeastrum hybrid lectin (HHL), and Aleuria aurantia lectin (AAL) were higher in the untreated KBD patients than in the control group. Increased levels of HHL, MAL-II, and GSL-I in the untreated KBD patients discriminated them in particular from the treated ones. Jacalin was lower in the untreated KBD patients compared to the treated KBD and control groups. In serum lectin microarray, HHL and peanut agglutinin (PNA) were increased in the untreated KBD group in comparison to the control one. AAL, Phaseolus vulgaris agglutinin (E+L) (PHA-E+L), and Psophocarpus tetragonolobus lectin I (PTL-I) were lower in the untreated KBD patients compared to the treated KBD and control groups. Hyaluronate treatment appeared to normalize SNA, AAL, and MAL-II levels in saliva, and HHL, PNA, AAL, PTL-I, and PHA-E+L levels in serum. Saliva reversed microarray verification confirmed significant differences between the groups in SNA and Jacalin, in particular for GSL-I levels, while serum reversed microarray verification indicated that HHL, PNA, and AAL levels returned to normal levels after the hyaluronate treatment. Lectin blot confirmed significant differences in HHL, AAL, and Jacalin in saliva, and HHL, PNA, PHA-E+L, and AAL in serum. Conclusion: HHL in saliva and serum may be a valuable diagnostic biomarker of KBD, and it may be used as follow-up for the hyaluronate treatment.


Assuntos
Glicoproteínas/metabolismo , Ácido Hialurônico/uso terapêutico , Doença de Kashin-Bek/tratamento farmacológico , Doença de Kashin-Bek/epidemiologia , Osteoartrite/tratamento farmacológico , Osteoartrite/epidemiologia , Aglutininas/metabolismo , Estudos de Casos e Controles , China/epidemiologia , Doenças Endêmicas , Feminino , Glicosilação , Humanos , Lectinas/metabolismo , Masculino , Pessoa de Meia-Idade , Saliva/química
15.
J Peripher Nerv Syst ; 24(2): 195-206, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31119823

RESUMO

The blood-nerve barrier (BNB) formed by tight junction-forming endoneurial microvessels located in the innermost compartment of peripheral nerves, and the perineurium serve to maintain the internal microenvironment required for normal signal transduction. The specific molecular components that define the normal adult human BNB are not fully known. Guided by data derived from the adult human BNB transcriptome, we evaluated the in situ expression of 25 junctional complex, transporter, cell membrane, and cytoskeletal proteins in four histologically normal adult sural nerves by indirect fluorescent immunohistochemistry to determine proteins specifically expressed by restrictive endoneurial microvascular endothelium. Using Ulex Europaeus Agglutinin-1 expression to detect endothelial cells, we ascertained that the selected proteins were uniformly expressed in ≥90% of endoneurial microvessels. P-glycoprotein (also known as adenosine triphosphate-binding cassette subfamily B member 1) and solute carrier family 1 member 1 demonstrated restricted expression by endoneurial endothelium only, with classic tight junction protein claudin-5 also expressed on fenestrated epineurial macrovessels, and vascular-specific adherens junction protein cadherin-5 also expressed by the perineurium. The expression profiles of the selected proteins provide significant insight into the molecular composition of normal adult peripheral nerves. Further work is required to elucidate the human adult BNB molecular signature in order to better understand its development and devise strategies to restore function in peripheral neuropathies.


Assuntos
Barreira Hematoneural/metabolismo , Microvasos/metabolismo , Nervos Periféricos/metabolismo , Transcriptoma , Idoso , Aglutininas/metabolismo , Células Endoteliais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
16.
Chembiochem ; 20(13): 1688-1692, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30828921

RESUMO

The fundamental importance of protein-glycan recognition calls for specific and sensitive high-resolution techniques for their detailed analysis. After the introduction of 19 F NMR spectroscopy to study the recognition of fluorinated glycans, a new 77 Se NMR spectroscopy method is presented for complementary studies of selenoglycans with optimised resolution and sensitivity, in which direct NMR spectroscopy detection on 77 Se is replaced by its indirect observation in a 2D 1 H,77 Se HSQMBC spectrum. In contrast to OH/F substitution, O/Se exchange allows the glycosidic bond to be targeted. As an example, selenodigalactoside recognition by three human galectins and a plant toxin is readily indicated by signal attenuation and line broadening in the 2D 1 H,77 Se HSQMBC spectrum, in which CPMG-INEPT long-range transfer ensures maximal detection sensitivity, clean signal phases, and reliable ligand ranking. By monitoring competitive displacement of a selenated spy ligand, the selective 77 Se NMR spectroscopy approach may also be used to screen non-selenated compounds. Finally, 1 H,77 Se CPMG-INEPT transfer allows further NMR sensors of molecular interaction to be combined with the specificity and resolution of 77 Se NMR spectroscopy.


Assuntos
Galectinas/metabolismo , Glicosídeos/metabolismo , Compostos Organosselênicos/metabolismo , Aglutininas/metabolismo , Glicosídeos/química , Humanos , Isótopos , Ligantes , Espectroscopia de Ressonância Magnética/métodos , Compostos Organosselênicos/química , Selênio , Viscum album/química
17.
Nanomedicine ; 18: 21-30, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30844577

RESUMO

Lactosylated albumin is currently used as a radiopharmaceutical agent to image the liver asialoglycoprotein receptors and quantify hepatic liver function in various diseases. A lactosylated protein (LACTAL) conjugate showed excellent liver uptake compared to non-lactosylated protein and a high signal to noise ratio, based on the biodistribution in mice using 99mTc-scintigraphy. However, in the laboratory, it is useful to have a method that can be used in daily practice to quantify cellular targeting or biodistribution. We propose a methodology from synthesis validation to pre-clinical demonstration and introduce a new practical detector (LACTAL.Eu) of the LACTAL molecule in biological media. We confirmed the purity and colloidal stability of the sample through physical analytical techniques, then showed the absence of in vitro toxicity of the agent and demonstrated in vitro targeting. Taking advantage of the fluorescence decay of the lanthanide, we performed measurements directly on the cell media without any further treatment. Finally, biodistribution in mice was confirmed by ex vivo measurements.


Assuntos
Európio/química , Lactose/química , Albumina Sérica Humana/química , Coloração e Rotulagem , Aglutininas/metabolismo , Animais , Feminino , Glicosilação , Células Hep G2 , Humanos , Camundongos Endogâmicos BALB C , Ricina/metabolismo , Distribuição Tecidual
18.
Stem Cells Transl Med ; 7(12): 876-886, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30255987

RESUMO

Autologous adipose tissue is used for tissue repletion and/or regeneration as an intact lipoaspirate or as enzymatically derived stromal vascular fraction (SVF), which may be first cultured into mesenchymal stem cells (MSCs). Alternatively, transplant of autologous adipose tissue mechanically fragmented into submillimeter clusters has recently showed remarkable efficacy in diverse therapeutic indications. To document the biologic basis of the regenerative potential of microfragmented adipose tissue, we first analyzed the distribution of perivascular presumptive MSCs in adipose tissue processed with the Lipogems technology, observing a significant enrichment in pericytes, at the expense of adventitial cells, as compared to isogenic enzymatically processed lipoaspirates. The importance of MSCs as trophic and immunomodulatory cells, due to the secretion of specific factors, has been described. Therefore, we investigated protein secretion by cultured adipose tissue clusters or enzymatically derived SVF using secretome arrays. In culture, microfragmented adipose tissue releases many more growth factors and cytokines involved in tissue repair and regeneration, noticeably via angiogenesis, compared to isogenic SVF. Therefore, we suggest that the efficient tissue repair/regeneration observed after transplantation of microfragmented adipose tissue is due to the secretory ability of the intact perivascular niche. Stem Cells Translational Medicine 2018;7:876-886.


Assuntos
Tecido Adiposo/metabolismo , Pericitos/metabolismo , Gordura Abdominal/citologia , Gordura Abdominal/metabolismo , Tecido Adiposo/citologia , Adulto , Idoso , Aglutininas/metabolismo , Proteínas Angiogênicas/metabolismo , Colagenases/metabolismo , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pessoa de Meia-Idade , Pericitos/citologia , Proteoma/análise
19.
Plant Cell Rep ; 37(6): 849-863, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29520589

RESUMO

KEY MESSAGE: Transgenic Brassica juncea plants expressing Colocasia esculenta tuber agglutinin (CEA) shows the non-allergenic nature of the expressed protein leading to enhanced mortality and reduced fecundity of mustard aphid-Lipaphis erysimi. Lipaphis erysimi (common name: mustard aphid) is the most devastating sucking insect pest of Indian mustard (Brassica juncea L.). Colocasia esculenta tuber agglutinin (CEA), a GNA (Galanthus nivalis agglutinin)-related lectin has previously been reported by the present group to be effective against a wide array of hemipteran insects in artificial diet-based bioassays. In the present study, efficacy of CEA in controlling L. erysimi has been established through the development of transgenic B. juncea expressing this novel lectin. Southern hybridization of the transgenic plants confirmed stable integration of cea gene. Expression of CEA in T0, T1 and T2 transgenic plants was confirmed through western blot analysis. Level of expression of CEA in the T2 transgenic B. juncea ranged from 0.2 to 0.47% of the total soluble protein. In the in planta insect bioassays, the CEA expressing B. juncea lines exhibited enhanced insect mortality of 70-81.67%, whereas fecundity of L. erysimi was reduced by 49.35-62.11% compared to the control plants. Biosafety assessment of the transgenic B. juncea protein containing CEA was carried out by weight of evidence approach following the recommendations by FAO/WHO (Evaluation of the allergenicity of genetically modified foods: report of a joint FAO/WHO expert consultation, 22-25 Jan, Rome, http://www.fao.org/docrep/007/y0820e/y0820e00.HTM , 2001), Codex (Codex principles and guidelines on foods derived from biotechnology, Food and Agriculture Organization of the United Nations, Rome; Codex, Codex principles and guidelines on foods derived from biotechnology, Food and Agriculture Organization of the United Nations, Rome, 2003) and ICMR (Indian Council of Medical Research, guidelines for safety assessment of food derived from genetically engineered plants, http://www.icmr.nic.in/guide/Guidelines%20for%20Genetically%20Engineered%20Plants.pdf , 2008). Bioinformatics analysis, pepsin digestibility, thermal stability assay, immuno-screening and allergenicity assessment in BALB/c mice model demonstrated that the expressed CEA protein from transgenic B. juncea does not incite any allergenic response. The present study establishes CEA as an efficient insecticidal and non-allergenic protein to be utilized for controlling mustard aphid and similar hemipteran insects through the development of genetically modified plants.


Assuntos
Aglutininas/metabolismo , Afídeos/fisiologia , Colocasia/genética , Mostardeira/imunologia , Doenças das Plantas/imunologia , Aglutininas/genética , Alérgenos/imunologia , Animais , Feminino , Camundongos Endogâmicos BALB C , Mostardeira/genética , Mostardeira/parasitologia , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tubérculos/genética , Plantas Geneticamente Modificadas
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