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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.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
Bioelectrochemistry ; 117: 89-94, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28651174

RESUMO

In recent decades, it has become clear that most of human proteins are glycosylated and that protein glycosylation plays an important role in health and diseases. At present, simple, fast and inexpensive methods are sought for clinical applications and particularly for improved diagnostics of various diseases, including cancer. We propose a label- and reagent-free electrochemical method based on chronopotentiometric stripping (CPS) analysis and a hanging mercury drop electrode for the detection of interaction of sialylated protein biomarker a prostate specific antigen (PSA) with two important lectins: Sambucus nigra agglutinin (SNA) and Maackia amurensis agglutinin (MAA). Incubation of PSA-modified electrode with specific SNA lectin resulted in an increase of CPS peak H of the complex as compared to this peak of individual PSA. By adjusting polarization current and temperature, PSA-MAA interaction can be either eliminated or distinguished from the more abundant PSA-SNA complex. CPS data were in a good agreement with the data obtained by complementary methods, namely surface plasmon resonance and fluorescent lectin microarray. It can be anticipated that CPS will find application in glycomics and proteomics.


Assuntos
Aglutininas/metabolismo , Condutividade Elétrica , Ácido N-Acetilneuramínico/metabolismo , Antígeno Prostático Específico/química , Antígeno Prostático Específico/metabolismo , Eletroquímica , Maackia/química , Sambucus nigra/química
12.
Neurotox Res ; 31(4): 570-577, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28124768

RESUMO

Animal models, such as cuprizone (bis-cyclohexanone oxaldihydrazone) feeding, are helpful to study experimental demyelination and remyelination in the context of diseases like multiple sclerosis. Cuprizone is a copper chelator, which when supplemented to the normal food of C57BL/6J mice in a concentration of 0.2% leads to oligodendroglial loss, subsequent microglia and astrocyte activation, resulting in demyelination. Termination of the cuprizone diet results in remyelination, promoted by newly formed mature oligodendrocytes. The exact mode of cuprizone's action is not well understood, and information about its inactivation and cleavage are still not available. The knowledge of these processes could lead to a better understanding of cuprizone's mode of action, as well as a safer handling of this toxin. We therefore performed experiments with the aim to inactivate cuprizone by thermal heating, since it was suggested in the past that cuprizone is heat sensitive. C57BL/6J mice were fed for 4 weeks with 0.2% cuprizone, either thermally pretreated (60, 80, 105, 121 °C) or not heated. In addition, primary rat oligodendrocytes, as a known selective toxic target of cuprizone, were incubated with 350 µM cuprizone solutions, which were either thermally pretreated or not. Our results demonstrate that none of the tested thermal pretreatment conditions could abrogate or restrict the toxic and demyelinating effects of cuprizone, neither in vitro nor in vivo. In conclusion, the current study rebuts the hypothesis of cuprizone as a heat-sensitive compound, as well as the assumption that heat exposure is a reason for an insufficient demyelination of cuprizone-containing pellets.


Assuntos
Cuprizona/toxicidade , Doenças Desmielinizantes/metabolismo , Temperatura Alta , Oligodendroglia/efeitos dos fármacos , Proteína da Polipose Adenomatosa do Colo/metabolismo , Aglutininas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Córtex Cerebral/metabolismo , Corpo Caloso/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Proteína Glial Fibrilar Ácida/metabolismo , Camundongos , Proteína Básica da Mielina/metabolismo , Oligodendroglia/metabolismo , Cultura Primária de Células , Ratos
13.
PLoS One ; 11(2): e0147867, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26828433

RESUMO

Pre-eclampsia is a leading cause of maternal and perinatal morbidity and mortality worldwide. The etiology is not clear, but an immune attack towards components of placenta or fetus has been indicated. This involves activation of the complement system in the placenta. We have previously described the presence of the complement-regulating protein salivary scavenger and agglutinin (SALSA) in amniotic fluid. In this study we investigated the potential role of SALSA in pregnancy by analyzing its presence in amniotic fluid and placental tissue during healthy and complicated pregnancies. SALSA levels in amniotic fluid increased during pregnancy. Before 20 weeks of gestation the levels were slightly higher in patients who later developed pre-eclampsia than in gestation age-matched controls. In the placenta of pre-eclamptic patients syncytial damage is often followed by the formation of fibrinoid structures. SALSA was found clustered into these fibrinoid structures in partial co-localization with complement C1q and fibronectin. In vitro analysis showed direct protein binding of SALSA to fibronectin. SALSA binds also to fibrin/fibrinogen but did not interfere with the blood clotting process in vitro. Thus, in addition to antimicrobial defense and epithelial differentiation, the data presented here suggest that SALSA, together with fibronectin and C1q, may be involved in the containment of injured placental structures into fibrinoids.


Assuntos
Aglutininas/metabolismo , Complicações na Gravidez/metabolismo , Receptores de Superfície Celular/metabolismo , Saliva/metabolismo , Líquido Amniótico/metabolismo , Coagulação Sanguínea , Proteínas de Ligação ao Cálcio , Complemento C1q/metabolismo , Proteínas de Ligação a DNA , Feminino , Fibronectinas/metabolismo , Imunofluorescência , Humanos , Placenta/metabolismo , Gravidez , Primeiro Trimestre da Gravidez/sangue , Proteínas Supressoras de Tumor
14.
Int J Biol Macromol ; 84: 208-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706839

RESUMO

Isolated caprine epididymal plasma glycoprotein "anti sticking factor" (ASF) interacts with caudal sperm surface in a D-galactose dependent manner. ASF acts as a Ca(2+) dependent soluble lectin principally activated in acidic pH. As a D-galactose specific lectin, it has a specific affinity for fibronectin as well as fibronectin receptor, i.e. integrins α5ß3 and α5ß1. By virtue of this particular property, it hampers the in vitro adhesion of the adherent breast cancer cell MCF7 with fibronectin. The effective anti-adhesive concentration of ASF promotes p53 dependent apoptosis in MCF7, which was established by Hoechst 33342 staining, DNA fragmentation assay, FITC tagged Annexin-V flowcytometry and western blot analysis. We suggest that ASF inhibits fibronectin-integrin interactions by binding with them and induces adhesion dependent apoptosis on adherent MCF7.


Assuntos
Apoptose , Epididimo/metabolismo , Glicoproteínas/metabolismo , Lectinas/metabolismo , Aglutininas/metabolismo , Animais , Adesão Celular , Matriz Extracelular , Proteínas da Matriz Extracelular/metabolismo , Citometria de Fluxo , Expressão Gênica , Glicoproteínas/isolamento & purificação , Cabras , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Masculino , Ligação Proteica , Espermatozoides/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Nephrol Dial Transplant ; 30(8): 1315-21, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26109484

RESUMO

BACKGROUND: Galactose-deficient IgA1 (Gd-IgA1) is a critical effector molecule in the pathogenesis of IgA nephropathy (IgAN). Although many researchers have measured serum levels of Gd-IgA1 using snail helix aspersa agglutinin (HAA) lectin-based assay, the lectin-dependent assay has some serious problems in robustness. In this study, we aimed to establish a more robust and stable enzyme-linked immunosorbent assay (ELISA) method that uses a specific monoclonal antibody to recognize a hinge region in human Gd-IgA1 (Gd-IgA1 ELISA). METHODS: Rats were immunized with human Gd-IgA1 hinge region peptide to obtain Gd-IgA1-specific monoclonal antibody KM55. Gd-IgA1 ELISA for specifically detecting serum Gd-IgA1 was consequently constructed. Serum Gd-IgA1 concentrations in human subjects were measured using KM55 ELISA assay. To further confirm specificity of the Gd-IgA1-specific antibody, KM55 was also applied for immunofluorescence staining of glomerular Gd-IgA1 in paraffin-embedded sections of renal biopsy specimens. RESULTS: Measurement of serum levels of Gd-IgA1 in human subjects by Gd-IgA1 ELISA revealed increased serum Gd-IgA1 level in patients with IgAN compared with patients with other renal diseases or non-renal diseases. Importantly, the results obtained from Gd-IgA1 ELISA positively correlated with those from the HAA lectin-based assay (R = 0.75). Immunofluorescence staining of renal biopsy specimens with KM55 detected glomerular co-localization of Gd-IgA1 and IgA. CONCLUSION: This novel lectin-independent method with KM55 for measuring serum levels of Gd-IgA1 can pave the way for more convincing diagnosis and activity assessment of IgAN, and can expedite clinical research to better understand this difficult disease.


Assuntos
Biomarcadores/sangue , Galactose/deficiência , Glomerulonefrite por IGA/diagnóstico , Imunoglobulina A/sangue , Glomérulos Renais/patologia , Lectinas/metabolismo , Aglutininas/metabolismo , Animais , Anticorpos Monoclonais , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Glomerulonefrite por IGA/sangue , Humanos , Glomérulos Renais/metabolismo , Ratos , Ratos Sprague-Dawley
16.
Biochimie ; 115: 93-107, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25978938

RESUMO

Maackia amurensis agglutinin (MAA) is gaining recognition as the potential diagnostic agent for cancer. Previous studies from our laboratory have demonstrated that this lectin could interact specifically with the cells and biopsy samples of non-small cell lung cancer (NSCLC) origin but not with normal lung fibroblast cells. Moreover, this lectin was also found to induce apoptosis in NSCLC cells. Further, the biological activity of this lectin was shown to survive gastrointestinal proteolysis and inhibit malignant cell growth and tumorigenesis in mice model of melanoma thereby indicating the therapeutic potential of this lectin. Paclitaxel is one of the widely used traditional chemotherapeutic drugs for treatment of NSCLC but it exerts side-effects on normal healthy cells too. Studies have revealed that lectins have potential to act as an adjuvant chemotherapeutic agent in cancer of different origin. Thus, in the present study, an attempt was made to assess the chemo-adjuvant role of MAA in three types of NSCLC cell lines [adenocarcinoma cell line (A549), squamous cell carcinoma cell line (NCI-H520) and large cell carcinoma cell line (NCI-H460)]. We have observed that the non-cytotoxic concentration of this lectin was able to enhance the cytotoxic activity of Paclitaxel even at low dose by inducing apoptosis through intrinsic/mitochondrial pathway in all the three types of NSCLC cell lines, although the involvement of extrinsic pathway of apoptosis in case of NCI-H460 cell line could not be ruled out. Further, this lectin was also found to augment the chemo-preventive activity of this drug by arresting cells in G2-M phase of the cell cycle. Collectively, our results have suggested that Maackia amurensis agglutinin may have the potential to be used as adjuvant chemotherapeutic agent in case of NSCLC.


Assuntos
Aglutininas/farmacologia , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Maackia/química , Paclitaxel/farmacologia , Aglutininas/metabolismo , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Lectinas de Plantas/metabolismo
17.
PLoS One ; 10(1): e0116649, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25629615

RESUMO

High rate of fetal mortality in ruminant somatic cell nuclear transfer (SCNT) pregnancies is due, at least in part, to immune-mediated abortion of fetuses. In the present study, goat uterine leukocytes were isolated by Dolichos biflorus agglutinin (DBA) coated magnetic beads, and with majority being were CD56+CD16- in phenotype with low levels of perforin and Granzyme B expression. The responses of the isolated cells to SCNT and in vitro fertilization (IVF) embryos conditioned mediums containing hormone steroids were compared by measuring their phenotype and cytokines expression. The results showed there was a 2-fold increase in the numbers of isolated uterine leukocytes after incubation with different conditioned mediums for 120 h. However, significantly lower percentage and absolute numbers of uterine CD56+CD16- leukocytes incubated with SCNT conditioned mediums were detected as compared with those incubated with IVF conditioned mediums (P < 0.05). The group treated with progesterone (P4) or the combination of P4 and 17ß-estradiol (E2) were associated with significantly higher percentage and absolute numbers of CD56+CD16- cells as compared with those treated with E2 alone (P < 0.05). Furthermore, in the presence of steroids, the isolated leukocytes incubated with SCNT conditioned mediums associated with greater levels of IFN-γ secretion and expression, as well as lesser levels of VEGF, as compared with those treated with IVF conditioned mediums (P < 0.05). In conclusion, this study demonstrates that SCNT embryos have a profound effect on the phenotype expression of goat uterine DBA+ leukocytes, as well as the secretion and expression of IFN-γ and VEGF by these cells in vitro.


Assuntos
Aglutininas/metabolismo , Diferenciação Celular , Citocinas/metabolismo , Leucócitos/citologia , Leucócitos/metabolismo , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Técnicas de Cultura Embrionária , Embrião de Mamíferos/metabolismo , Endométrio/citologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Fertilização in vitro , Cabras , Imunofenotipagem , Fenótipo , Receptores de Esteroides/metabolismo , Útero
18.
Clin Cancer Res ; 20(23): 6117-26, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25320359

RESUMO

PURPOSE: The ABO gene locus is associated with the risk of developing pancreatic ductal adenocarcinoma (PDAC) resulting in an increased incidence in individuals with non-O blood groups. Up to 90% of PDAC specimens display alterations in mucin type O-GalNAc glycosylation. Because aberrant O-GalNAc glycans (Tn and T antigen) are structurally related to blood group A and B glycans, we investigated the role of IgM isoagglutinins in PDAC. EXPERIMENTAL DESIGN: Binding studies of IgM isoagglutinins toward blood group A, B, Tn antigen, and T antigen glycoconjugates from patients with PDAC and healthy individuals were conducted. Isoagglutinin titers and total IgM were compared between patients with PDAC and control group. An anti-A antibody was used for immunoprecipitation of aberrant O-glycosylated tumor proteins and subsequent mass spectromic analysis. RESULTS: We found that IgM isoagglutinins bind blood group antigens, Tn and T glycoconjugates as well as tumor-derived glycoproteins. Blood group A isoagglutinins exhibited a strong binding toward blood group B antigen and T antigen, whereas blood group B showed binding to blood group A antigen and Tn antigen. Furthermore, we confirmed a decreased frequency in individuals with blood group O and observed a significant decrease of IgM isoagglutinin titers in PDAC sera compared with control sera, whereas total IgM levels were unaltered. We identified new PDAC-derived O-GalNAc glycoproteins by mass spectrometry using a blood group A-specific antibody. CONCLUSION: Our data elucidated a novel interaction of blood group IgM isoagglutinins and PDAC O-GalNAc glycoproteins that may contribute to the pathogenesis and progression of pancreatic cancer.


Assuntos
Sistema ABO de Grupos Sanguíneos , Aglutininas/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Imunoglobulina M/metabolismo , Neoplasias Pancreáticas/metabolismo , Polissacarídeos/metabolismo , Sistema ABO de Grupos Sanguíneos/imunologia , Adulto , Idoso , Aglutininas/sangue , Aglutininas/imunologia , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Estudos de Casos e Controles , Feminino , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Ligação Proteica , Adulto Jovem
19.
J Antimicrob Chemother ; 69(10): 2746-58, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24970741

RESUMO

OBJECTIVES: Oscillatoria agardhii agglutinin homologue (OAAH) proteins belong to a recently discovered lectin family. The founding member OAA and a designed hybrid OAAH (OPA) recognize similar but unique carbohydrate structures of Man-9, compared with other antiviral carbohydrate-binding agents (CBAs). These two newly described CBAs were evaluated for their inactivating properties on HIV replication and transmission and for their potential as microbicides. METHODS: Various cellular assays were used to determine antiviral activity against wild-type and certain CBA-resistant HIV-1 strains: (i) free HIV virion infection in human T lymphoma cell lines and PBMCs; (ii) syncytium formation assay using persistently HIV-infected T cells and non-infected CD4+ T cells; (iii) DC-SIGN-mediated viral capture; and (iv) transmission to uninfected CD4+ T cells. OAA and OPA were also evaluated for their mitogenic properties and potential synergistic effects using other CBAs. RESULTS: OAA and OPA inhibit HIV replication, syncytium formation between HIV-1-infected and uninfected T cells, DC-SIGN-mediated HIV-1 capture and transmission to CD4+ target T cells, thereby rendering a variety of HIV-1 and HIV-2 clinical isolates non-infectious, independent of their coreceptor use. Both CBAs competitively inhibit the binding of the Manα(1-2)Man-specific 2G12 monoclonal antibody (mAb) as shown by flow cytometry and surface plasmon resonance analysis. The HIV-1 NL4.3(2G12res), NL4.3(MVNres) and IIIB(GRFTres) strains were equally inhibited as the wild-type HIV-1 strains by these CBAs. Combination studies indicate that OAA and OPA act synergistically with Hippeastrum hybrid agglutinin, 2G12 mAb and griffithsin (GRFT), with the exception of OPA/GRFT. CONCLUSIONS: OAA and OPA are unique CBAs with broad-spectrum anti-HIV activity; however, further optimization will be necessary for microbicidal application.


Assuntos
Aglutininas/farmacologia , Fármacos Anti-HIV/farmacologia , HIV-1/efeitos dos fármacos , Lectinas/farmacologia , Oscillatoria/metabolismo , Aglutininas/metabolismo , Fármacos Anti-HIV/metabolismo , Proteínas de Bactérias/farmacologia , Linhagem Celular , Farmacorresistência Viral , Células Gigantes/efeitos dos fármacos , Células Gigantes/virologia , Proteína gp120 do Envelope de HIV/metabolismo , Humanos , Concentração Inibidora 50 , Cinética , Lectinas/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/virologia , Testes de Sensibilidade Microbiana , Ligação Proteica
20.
Biochem Biophys Res Commun ; 447(4): 586-9, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24747075

RESUMO

The Marasmius oreades mushroom agglutinin (MOA) is a blood group B-specific lectin carrying an active proteolytic domain. Its enzymatic activity has recently been shown to be critical for toxicity of MOA toward the fungivorous soil nematode Caenorhabditis elegans. Here we present evidence that MOA also induces cytotoxicity in a cellular model system (murine NIH/3T3 cells), by inhibiting protein synthesis, and that cytotoxicity correlates, at least in part, with proteolytic activity. A peptide-array screen identified the apoptosis mediator BAX as a potential proteolytic substrate and further suggests a variety of bacterial and fungal peptides as potential substrates. These findings are in line with the suggestion that MOA and related proteases may play a role for host defense.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proteínas Fúngicas/farmacologia , Proteína X Associada a bcl-2/metabolismo , Aglutininas/metabolismo , Aglutininas/farmacologia , Aglutininas/toxicidade , Substituição de Aminoácidos , Animais , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/toxicidade , Variação Genética , Lectinas/metabolismo , Lectinas/farmacologia , Lectinas/toxicidade , Marasmius/química , Marasmius/genética , Camundongos , Células NIH 3T3 , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Ácido Nucleico/toxicidade , Inibidores da Síntese de Proteínas/farmacologia , Inibidores da Síntese de Proteínas/toxicidade
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