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1.
J Agric Food Chem ; 67(31): 8660-8667, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298531

RESUMO

Soybean allergens in food samples are currently detected in most cases using enzyme-linked immunosorbent assays (ELISAs) based on antibodies raised against bulk soybean proteins or specifically targeting soybean trypsin inhibitor, conglycinin, or glycinin. The various commercial ELISAs lack standardized reference material, and the results are often inaccurate because the antibodies cross-react with proteins from other legumes. Furthermore, the isolation of allergenic proteins involves laborious denaturing extraction conditions. To tackle these challenges, we have developed a novel sandwich ELISA based on monoclonal antibodies raised against the soybean 2S albumin Gly m 8 and a recombinant Gly m 8 reference protein with native-analogous characteristics. The antibodies do not cross-react with other legume proteins, and the extraordinary stability and solubility of Gly m 8 allows it to be extracted even from complex matrices after processing. The Gly m 8 ELISA therefore achieves greater specificity and reproducibility than current ELISA tests.


Assuntos
Albuminas 2S de Plantas/análise , Alérgenos/análise , Ensaio de Imunoadsorção Enzimática/métodos , Fast Foods/análise , Contaminação de Alimentos/análise , Proteínas de Soja/análise , Soja/imunologia , Albuminas 2S de Plantas/imunologia , Alérgenos/imunologia , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/imunologia , Reações Cruzadas , Proteínas de Soja/imunologia , Soja/química
2.
Vet Immunol Immunopathol ; 213: 109889, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307671

RESUMO

Blocking immunoglobulin G (IgG) binding receptors on leukocytes is an established and highly recommended preventive procedure for immunological assays. Failing to prevent such nonspecific binding can lead to erroneous results. Several studies testing different blocking reagents have been performed in murine or human cells, however, there are no specific studies on bovine cells. Our study aimed to investigate the efficiency of blocking reagents to inhibit the nonspecific binding of mouse monoclonal antibodies (mAbs) to bovine peripheral blood cells. We observed nonspecific interactions of IgG2a and IgG2b negative isotypes with bovine leukocytes, but not IgG1. We found that these nonspecific bindings could be eliminated by blocking with purified mouse IgG, whereas little or no blocking effect was observed when bovine serum or Mouse Seroblock FcR were applied. Moreover, in the absence of an efficient blocking reagent, the percentage of CD335 positive cells was significantly higher than in the group previously blocked with mouse IgG. Based on these results, and due to the lack of specific commercial blocking reagents for bovine cells, our recommendation is to use purified mouse IgG as a blocking reagent for immune assays targeting bovine leukocytes in order to enhance the accuracy of the results.


Assuntos
Anticorpos Monoclonais/imunologia , Imunofenotipagem/métodos , Leucócitos Mononucleares/imunologia , Receptores Fc/imunologia , Erro Experimental , Animais , Bovinos , Epitopos/imunologia , Citometria de Fluxo , Imunoglobulina G/imunologia , Imunoglobulina G/isolamento & purificação , Imunofenotipagem/normas , Camundongos , Ligação Proteica
3.
Artigo em Chinês | MEDLINE | ID: mdl-31315359

RESUMO

Objective: To observe the effect of tumor necrosis factor-α (TNF-α) monoclonal antibody on autophagy in allergic rhinitis (AR) mice. Methods: Thirty six weeks old BALB/c mice were randomly divided by random number table method into five groups: control group, model group (AR group), TNF-α antibody intervention group (AR+TNF-α group), autophagy inhibitor (3-methylindole, 3-NA) intervention group (AR+3-MA group), TNF-α antibody combined with autophagy inducer rapamycin (RAP) intervention group (AR+TNF-α+RAP group), with 6 mice in each group. AR model was established by conventional method, the corresponding reagent was administered before nasal cavity stimulation sensitization and during the whole experiment. Behavioral scores of mice were obtained, blood was collected from the eye socket, and mice in each group were sacrificed to collect nasal mucosa tissue samples. Pathological changes of nasal mucosa were observed by hematoxylin-eosin staining. Expression levels of inflammatory factor and IgE in serum were detected by enzyme-linked immunosorbent assay (ELISA). Expressions of autophagy related indicators microtubule-associated protein-1 light chain-3B (LC3B), Beclin-1, sequestosome1 (p62), autophagy-related 5 (ATG5), autophagy-related 7 (ATG7) were measured by Real-time PCR and Western blot. The aggregation of LC3B protein was observed by immunofluorescence. SPSS 19.0 software was used for statistical analysis. Results: Compared with the AR model group, symptoms of AR in AR+TNF-α group and AR+3-MA group were mild; the pathological changes of nasal mucosa were weak; the expression of IgE, TNF-α, interleukin 4 (IL-4), interferon-γ (IFN-γ) in serum significantly reduced (IgE: 666.19±78.35 (x±s) vs. 692.38±64.29 vs. 1 059.05±146.44, TNF-α: 112.06±12.95 vs. 113.17±15.43 vs. 161.22±17.96, IL-4: 54.05±7.14 vs. 58.26±5.67 vs. 79.95±6.33, IFN-γ: 28.58±4.51 vs. 30.67±2.60 vs. 39.83±3.31, all P<0.05), and the expression of LC3B Ⅱ/Ⅰ, Beclin-1, ATG5, ATG7 in nasal mucosa significantly decreased, the expression of p62 significantly elevated. After intervention with autophagy inducer RAP, the therapeutic effect of TNF-α monoclonal antibodies on AR was antagonized. Conclusion: TNF-α monoclonal antibody significantly improves nasal symptoms in AR mice by inhibiting autophagy levels.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Autofagia/imunologia , Rinite Alérgica/tratamento farmacológico , Rinite Alérgica/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C
4.
Anal Chim Acta ; 1078: 142-150, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31358212

RESUMO

Mycotoxins and pesticides are prevalent in cereal food. It is difficult to detect these two kinds of hazard factors simultaneously in rapid assay. In order to find a solution to the problem, carbamates and aflatoxins were selected in this study to establish a rapid, on-site, and quantitative paper sensor. Two novel monoclonal antibodies (mAbs) against carbaryl and carbofuran (1D2 and G11) were developed. The IC50 values (half maximal inhibitory concentration) were 0.8 ng/mL and 217.6 ng/mL for carbaryl and carbofuran, respectively. Based on the sensitive and specific mAbs, a multi-TRFICA (time-resolved fluorescence) paper sensor was developed, which simultaneously detected six types of hazardous chemicals, including AFB1, AFB2, AFG1, AFG2, carbaryl, and carbofuran. A universal sample pretreatment method for mycotoxins and pesticides was explored to apply on established competitive indirect enzyme-linked immunosorbent assay (icELISA) and multi-TRFICA-paper sensor. The established paper sensor can be easily observed with naked eyes, qualitatively under a UV lamp, and quantitated using a home-made device. It exhibited a calculated limit of quantity for AFTs, carbaryl, and carbofuran of 0.03, 0.02, and 60.2 ng/mL in corn samples, respectively. The spiking-recoveries and real sample studies proved that multi-TRFICA-paper sensor is an accurate, sensitive, and high throughput detection method for simple and low-cost analysis in corn samples.


Assuntos
Aflatoxinas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Papel , Resíduos de Praguicidas/análise , Anticorpos Monoclonais/imunologia , Carbaril/imunologia , Carbofurano/imunologia , Európio/química , Fluorescência , Contaminação de Alimentos/análise , Nanopartículas Metálicas/química , Zea mays/química
5.
Int J Nanomedicine ; 14: 4293-4307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354261

RESUMO

Purpose: Antibodies are key reagents in the development of immunoassay. We attempted to develop high-performance CPP immunoassays using high-affinity monoclonal antibodies prepared via cytokine-assisted immunization. Methods: We used fetal liver tyrosine kinase 3 ligand (Flt3L), CC subtype chemokine ligand 20 (CCL20), and granulocyte-macrophage colony-stimulating factor (GM-CSF) to assist traditional subcutaneous immunization of preparing high-affinity monoclonal antibodies, and further to develop high-performance immunoassay methods for CPP. Results: This novel immune strategy significantly enhanced immune response against CPP. Six anti-CPP monoclonal antibodies (mAbs) with high affinity were successfully screened and selected for application in a fully automated magnetic chemiluminescence immunoassay (CLIA). This robust and rapid assay can efficiently detect CPP in the range of 1.2-1250 pmol L-1 with a detection limit of 6.25 pmol L-1. Significantly, the whole incubation process can be completed in 30 min as compared to about 4.5 hr for the control ELISA kit. Furthermore, this assay exhibited high sensitivity and specificity, low intra-assay and inter-assay coefficients of variation (CVs < 15%). The developed assay was applied in the detection of CPP in 115 random serum samples and results showed a high correlation with data obtained using a commercially available ELISA kit (correlation coefficient, 0.9737). Conclusion: Our assay could be applied in the point-of-care testing of CPP in the serum samples, and also the method developed in this study could be adopted to explore the detection and diagnosis of other biomarkers for various diseases.


Assuntos
Anticorpos Monoclonais/imunologia , Citocinas/metabolismo , Glicopeptídeos/sangue , Imunização , Imunoensaio/métodos , Medições Luminescentes/métodos , Testes Imediatos , Animais , Anticorpos Monoclonais/biossíntese , Feminino , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanopartículas de Magnetita/química , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade
6.
BMC Bioinformatics ; 20(1): 387, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296178

RESUMO

BACKGROUND: Bioinformatics methods are helpful to identify new molecules for diagnostic or therapeutic applications. For example, the use of peptides capable of mimicking binding sites has several benefits in replacing a protein which is difficult to produce, or toxic. Using peptides is less expensive. Peptides are easier to manipulate, and can be used as drugs. Continuous epitopes predicted by bioinformatics tools are commonly used and these sequential epitopes are used as is in further experiments. Numerous discontinuous epitope predictors have been developed but only two bioinformatics tools have been proposed so far to predict peptide sequences: Superficial and PEPOP 2.0. PEPOP 2.0 can generate series of peptide sequences that can replace continuous or discontinuous epitopes in their interaction with their cognate antibody. RESULTS: We have developed an improved version of PEPOP (PEPOP 2.0) dedicated to answer to experimentalists' need for a tool able to handle proteins and to turn them into peptides. The PEPOP 2.0 web site has been reorganized by peptide prediction category and is therefore better formulated to experimental designs. Since the first version of PEPOP, 32 new methods of peptide design were developed. In total, PEPOP 2.0 proposes 35 methods in which 34 deal specifically with discontinuous epitopes, the most represented epitope type in nature. CONCLUSION: Through the presentation of its user-friendly, well-structured new web site conceived in close proximity to experimentalists, we report original methods that show how PEPOP 2.0 can assist biologists in dealing with discontinuous epitopes.


Assuntos
Biologia Computacional/métodos , Epitopos/metabolismo , Software , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Epitopos/química , Soros Imunes , Internet , Camundongos , Peptídeos/sangue , Peptídeos/química , Peptídeos/imunologia , Domínios Proteicos , Proteínas/química
7.
Int J Oncol ; 55(1): 223-242, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31180528

RESUMO

The aim of this study was to examine the effects of 5­fluorouracil (5­FU), anti­epidermal growth factor receptor (EGFR) antibody and aspirin (ASA) on the characteristics of two CRC cell lines, HCT116 and HT29, maintained in a spherical culture system. We observed that the morphology of both the HCT116 and HT29 cell­derived spheres was significantly impaired and the size of the colonospheres was markedly reduced following treatment with the aforementioned three drugs. In contrast to adherent cultures, the spherical cultures were more resistant to the tested drugs, as was reflected by their capacity to re­create the colonospheres when sustained in serum­free medium. Flow cytometric analysis of the drug­treated HCT116 cell­derived spheres revealed changes in the fraction of cells expressing markers of cancer stem cells (CSCs), whereas the CSC phenotype of HT29 cell­derived colonospheres was affected to a lesser extent. All reagents enhanced the percentage of non­viable cells in the colonospheres despite the diminished fraction of active caspase­3­positive cells following treatment of the HT29 cell­derived spheres with anti­EGFR antibody. Increased autophagy, assessed by acridine orange staining, was noted following the incubation of the HT29­colonospheres with ASA and 5­FU in comparison to the control. Notably, the percentage of cyclooxygenase (COX)­2­positive cells was not affected by ASA, although its activity was markedly elevated in the colonospheres incubated with anti­EGFR antibody. On the whole, the findings of this study indicate that all the tested drugs were involved in different cellular processes, which suggests that they should be considered for the combined therapeutic treatment of CRC, particularly for targeting the population of CSC­like cells. Thus, cancer cell­derived spheres may be used as a preferable model for in vitro anticancer drug testing.


Assuntos
Anticorpos Monoclonais/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Aspirina/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/farmacologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Aspirina/administração & dosagem , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/metabolismo , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Proteína Ligante Fas/biossíntese , Fluoruracila/administração & dosagem , Células HCT116 , Células HT29 , Humanos , Esferoides Celulares , Receptor fas/biossíntese
8.
J Med Microbiol ; 68(7): 1021-1032, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31188094

RESUMO

INTRODUCTION: The spread of carbapenem-resistant Acinetobacter baumannii has led to a worldwide healthcare problem. Carbapenem resistance in A. baumannii is mainly mediated by the acquisition of the carbapenem-hydrolyzing oxacillinase OXA-23. The phenotypic detection of carbapenem-producing A. baumannii is challenging and time-consuming. Hence, there is an unmet medical need for reliable and rapid diagnostic tools to detect OXA-23-producing Acinetobacter isolates to enable successful patient management. AIM: Development of an immunochromatographic lateral flow test (ICT) for the rapid and reliable detection of OXA-23-producing carbapenem-resistant Acinetobacter isolates. METHODOLOGY: For the development of an antibody-based ICT, we generated anti-OXA-23 monoclonal antibodies (MoAbs) and screened them sequentially for their ability to bind native OXA-23. Selected OXA-23-specific MoAbs were tested in different combinations for their capacity to capture and detect OXA-23His6 by sandwich enzyme-linked immunosorbent assay (ELISA) and ICT. A well-characterized collection of carbapenem-resistant Acinetobacter isolates with defined carbapenem resistance mechanisms were used to evaluate the specificity of the final OXA-23 ICT prototype. RESULTS: The antibody pairs best suited for the sandwich ELISA format did not match the best pairs in the ICT format selected during the development process of the final prototype OXA-23 ICT. This prototype was able to differentiate between OXA-23 subfamily-mediated carbapenem resistance and carbapenem-resistant Acinetobacter isolates overexpressing other OXAs with 100  % specificity and a turnaround time of 20 min from culture plate to result. CONCLUSION: With this rapid detection assay one can save 12-48 h of diagnostic time, which could help avoid inappropriate use of carbapenems and enable earlier intervention to control the transmission of OXA-23-producing carbapenem-resistant Acinetobacter isolates to other patients and healthcare workers.


Assuntos
Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla , Imunoensaio/métodos , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/imunologia , Animais , Antibacterianos/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Proteínas de Bactérias , Carbapenêmicos/metabolismo , Clonagem Molecular , Feminino , Regulação Bacteriana da Expressão Gênica , Camundongos , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/imunologia , beta-Lactamases/metabolismo
9.
Anal Bioanal Chem ; 411(21): 5499-5507, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31179529

RESUMO

Anti-Müllerian hormone (AMH) is a biomarker for the assessment of female fertility. The accurate measurement of the concentration of AMH is relevant for the success of assisted reproductive therapies and diagnosis of clinical cases. In this study, we show that cytokines such as fetal liver tyrosine kinase 3 ligand (Flt3L), CC subtype chemokine ligand 20 (CCL20), granulocyte-macrophage colony-stimulating factor (GM-CSF), and ß2-microglobulin (ß2M) significantly enhance the immune response against AMH. Two anti-AMH monoclonal antibodies (mAbs) with high affinity were selected by biolayer interferometry (BLI) technology for application in a fully automated magnetic chemiluminescence immunoassay (CLIA). This robust and rapid assay can efficiently detect AMH in the range of 0.125~20 ng mL-1 with a detection limit of 0.099 ng mL-1. This immunoassay showed high specificity with no cross-reaction with structurally related proteins and some of the other members of the TGF-ß super family, such as inhibin A, activin A, follicle-stimulating hormone, and luteinizing hormone. The average recovery rates of three different batches were 100.19%, 102.72%, and 103.59%, respectively, with coefficients of variation of less than 12%. The developed assay was applied in the detection of AMH in 69 serum samples from randomly selected patients. Our data showed a high correlation with those obtained using commercially available ELISA kits (correlation coefficient, 0.9831). Hence, we suggest that this immunoassay could find application in the development of POCT for the diagnosis of AMH in clinical samples. Graphical abstract.


Assuntos
Hormônio Antimülleriano/metabolismo , Imunoensaio/métodos , Interferometria/métodos , Hormônio Antimülleriano/imunologia , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Calibragem , Citocinas/metabolismo , Feminino , Humanos
10.
BMC Infect Dis ; 19(1): 565, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253101

RESUMO

BACKGROUND: To detect carbapenemase-producing Gram-negative bacteria in bacterial laboratories at medical settings, a new immunochromatographic assay for New Delhi metallo-ß-lactamases (NDMs) was developed. METHODS: The immunochromatographic assay for New Delhi metallo-ß-lactamases producers was developed using rat monoclonal antibodies against NDMs. The assessment was performed using 350 isolates of Gram-negative bacteria, including Acinetobacter baumannii (51 isolates), Enterobacteriaceae (163 isolates), and Pseudomonas aeruginosa (136 isolates) obtained from 2015 to 2017 in medical settings in Myanmar. Of them, 302 isolates were resistant to carbapenems, including imipenem and/or meropenem. The blaNDM genes were identified by PCR and sequencing. RESULTS: Of the 350 clinical isolates tested, 164 (46.9%) (60 isolates of Escherichia coli, 51 isolates of Klebsiella pneumoniae, 25 isolates of Enterobacter cloacae, 23 isolates of P. aeruginosa, and 5 isolates of A. baumannii) were positive on this assay, and all the positive isolates harbored genes encoding NDM-1, - 4, - 5 and - 7. The remaining 186 (53.1%) isolates negative on the assay did not harbor genes encoding NDMs. The assay had a specificity of 100% and a sensitivity of 100%. The assessment revealed that more than 90% of carbapenem-resistant Enterobacteriaceae produced NDMs. CONCLUSIONS: The immunochromatographic assay is an easy-to-use and reliable kit for detection of NDMs-producing Gram-negative bacteria. The assay revealed that NDM-producing Enterobacteriaceae isolates are wide-spread in medical settings in Myanmar.


Assuntos
Bactérias Gram-Negativas/isolamento & purificação , Imunoensaio/métodos , beta-Lactamases/imunologia , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/isolamento & purificação , Animais , Antibacterianos/farmacologia , Anticorpos Monoclonais/imunologia , Farmacorresistência Bacteriana , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/genética , Humanos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Mianmar , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/isolamento & purificação , Ratos , beta-Lactamases/genética , beta-Lactamases/metabolismo
11.
Anal Bioanal Chem ; 411(17): 3881-3890, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31152222

RESUMO

Aflatoxin B1 (AFB1) is one of the major mycotoxins, which naturally occurs in food and agricultural products. In this study, a cyclic peptide (CVPSKPGLC) mimicking AFB1 was used to develop a biotinylated peptide-based immunoassay (bp-ELISA) for AFB1 determination. This cyclic peptide was isolated from a commercially available phage-displayed random 7-mer cyclic peptide library, and then synthesized chemically. Instead of phage particles, the peptide was biotinylated and used to detect AFB1 by bp-ELISA, with an IC50 of 0.92 ng/mL, which was approximately 60-fold better than that of phage ELISA. Good recoveries (83-102%) were obtained in spiked rice and corn samples, which were further validated by high-performance liquid chromatography-fluorescence detector. As better sensitivities (0.92-1.21 ng/mL) were obtained by bp-ELISA even using selected anti-AFB1 antibodies prepared previously in laboratory, this cyclic peptide is suitable as a substitute for synthetic competitive AFB1 antigens in food contamination monitoring. Graphical abstract.


Assuntos
Aflatoxina B1/imunologia , Antígenos/química , Antígenos/imunologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Biotina/química , Técnicas de Visualização da Superfície Celular , Cromatografia Líquida de Alta Pressão/métodos , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Contaminação de Alimentos/análise , Concentração Inibidora 50 , Limite de Detecção , Espectrometria de Fluorescência/métodos , Estreptavidina/química
12.
Dokl Biochem Biophys ; 485(1): 126-128, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31201631

RESUMO

We generated a novel human neutralizing human mAb RabD4 against rabies virus glycoprotein using in vitro stimulation of human peripheral B cells produced by immunized donor. The human mAb RabD4 showed a high antigen-binding activity and virus-neutralizing activity in the FAVN test with the CVS-11 rabies virus.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vírus da Raiva/imunologia , Proteínas Virais/imunologia , Humanos
13.
Food Chem ; 293: 144-150, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151594

RESUMO

Nobiletin, a polymethoxyflavone mainly found in citrus fruits, have been reported to exhibit various beneficial biological activities for human health. It is an important bioactive compound in traditional Chinese medicine, Pericarpium Citri Reticulatae and Fructus Aurantii. To detect the contents of nobiletin in citrus and herb samples, we developed an indirect competitive enzyme-linked immunosorbent assay (icELISA) based on monoclonal antibodies. It possessed a median inhibition concentration (IC50) of 2.43 ±â€¯0.19 ng/mL and a working range of 0.52-12.3 ng/mL. The assay exhibited the average recoveries of 72.5-85.3% in citrus peel, pulp and juice samples. Moreover, eleven citrus cultivars samples and four herb samples were also detected by the icELISA. The nobiletin content varied in different citrus cultivars samples and herb samples, which were confirmed by the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS). These results indicated that the developed immunoassay was suitable for detecting nobiletin in citrus and herb samples.


Assuntos
Citrus/química , Flavonas/análise , Anticorpos Monoclonais/imunologia , Citrus/metabolismo , Ensaio de Imunoadsorção Enzimática , Flavonas/química , Flavonas/imunologia , Frutas/química , Frutas/metabolismo , Sucos de Frutas e Vegetais/análise , Haptenos/química , Haptenos/imunologia , Medicina Tradicional Chinesa
14.
APMIS ; 127(8): 588-593, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31233243

RESUMO

Microfibrillar-associated protein 4 (MFAP4) is a non-structural matrix protein with cell regulatory activities and a potential as seromarker for fibrosis. We aimed to study the occurrence of MFAP4 in the synovial membrane from patients with rheumatoid arthritis (RA) vs osteoarthritis (OA). Formaldehyde-fixed synovial tissue sections, from patients with RA (N = 6) and OA (N = 6) undergoing total hip arthroplasty, were deparaffinized and immunostained with monoclonal antibodies against MFAP4. Elastin was detected using ElastiKit. MFAP4 in serum (sMFAP4) and synovial fluid was measured by an immunoassay. MFAP4 was present in synovial biopsies from both RA and OA patients, particularly prominent in deep arterioles where it colocalized with elastin. Notably however, MFAP4 was absent from the internal elastic lamina in RA arterioles irrespective of disease duration and synovitis activity, while present although with irregular staining patterns in OA specimens. sMFAP4 was increased in RA and OA serum vs healthy controls: median (interquartile range) 29.8 (25.3-39.1) and 25.5 U/L (18.1-43.3) vs 17.7 U/L (13.7-21.2), p = 0.006 and p = 0.02, respectively The concentration of synovial fluid was lower than in serum in both RA and OA. These findings may suggest that MFAP4 is involved in adaptive vessel wall remodeling associated with chronic joint disease.


Assuntos
Artrite Reumatoide/imunologia , Proteínas de Transporte/análise , Proteínas da Matriz Extracelular/análise , Glicoproteínas/análise , Osteoartrite/imunologia , Membrana Sinovial/imunologia , Idoso , Anticorpos Monoclonais/imunologia , Biomarcadores/análise , Proteínas de Transporte/imunologia , Estudos de Casos e Controles , Proteínas da Matriz Extracelular/imunologia , Feminino , Glicoproteínas/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Líquido Sinovial/química , Membrana Sinovial/patologia
15.
Nat Commun ; 10(1): 2699, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221976

RESUMO

Human cytomegalovirus (CMV) causes a wide array of disease to diverse populations of immune-compromised individuals. Thus, a more comprehensive understanding of how CMV enters numerous host cell types is necessary to further delineate the complex nature of CMV pathogenesis and to develop targeted therapeutics. To that end, we establish a vaccination strategy utilizing membrane vesicles derived from epithelial cells to generate a library of monoclonal antibodies (mAbs) targeting cell surface proteins in their native conformation. A high-throughput inhibition assay is employed to screen these antibodies for their ability to limit infection, and mAbs targeting CD46 are identified. In addition, a significant reduction of viral proliferation in CD46-KO epithelial cells confirms a role for CD46 function in viral dissemination. Further, we demonstrate a CD46-dependent entry pathway of virus infection in trophoblasts, but not in fibroblasts, highlighting the complexity of CMV entry and identifying CD46 as an entry factor in congenital infection.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Interações Hospedeiro-Patógeno/imunologia , Proteína Cofatora de Membrana/imunologia , Internalização do Vírus , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Linhagem Celular , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/virologia , Células Epiteliais/imunologia , Células Epiteliais/virologia , Fibroblastos/imunologia , Fibroblastos/virologia , Técnicas de Inativação de Genes , Humanos , Proteína Cofatora de Membrana/genética , RNA Interferente Pequeno/metabolismo , Trofoblastos/imunologia , Trofoblastos/virologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia
16.
Vet Microbiol ; 234: 83-91, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31213277

RESUMO

Since 2011, there have been outbreaks of pseudorabies (PR) in several pig farms despite vaccination coverage, which causes substantial economic loss to the swine industry in China. The emergence of a pseudorabies virusvariant strain with high virulence and antigenic variation (e.g., PRV ZJ01), is considered to be the primary cause. In this study, truncated gB, gC, and gE of PRV ZJ01 was expressed and used to generate seven monoclonal antibodies (mAbs) against gB, gC, or gE. An indirect immunofluorescence assay (IFA) revealed that these mAbs were specific against PRV. Subsequently we identified the B cell epitopes recognized by these mAbs by Western blot. The mAbs 5A2 and 6G5 against gB recognized the same B cell linear epitope at 576SAVATAA582, the mAb 5D10 against gC recognized the B cell linear epitope at 134GETFE138, mAb 7C5 against gC recognized the B cell linear epitope at 143RRGRFRSPDAD153, and mAbs 3E1, 3H8, and 4D2 against gE recognized the same B cell linear epitope at 151IGDYL155 of gE. Biological information analysis showed that these B cell linear epitopes are highly conserved among different PRV isolates and the epitope 143RRGRFRSPDAD153 with a high antigenic index and high hydrophilicity, fully exposed on the surface of the gC, is likely to be an important B cell epitope. These mAbs and their defined epitopes may provide useful tools for the study of the structure and function of the PRV protein, analysis of antigenic epitope characteristics, and establishment of antibody detection methods.


Assuntos
Anticorpos Monoclonais/imunologia , Epitopos de Linfócito B/imunologia , Pseudorraiva/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Linhagem Celular , Feminino , Hibridomas , Camundongos , Camundongos Endogâmicos BALB C , Suínos
17.
Parasitol Res ; 118(7): 2287-2293, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31168702

RESUMO

Schistosomiasis is a devastating disease caused by Schistosoma infection. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has emerged as a candidate vaccine component against Schistosoma japonicum, but only confers partial protection. Cytotoxic T lymphocyte antigen-4 (CTLA-4) regulates T cell activation and shows negative effects on vaccine-induced immune protection; however, its potential influence on the protective effects of a GAPDH vaccine against S. japonicum and the underlying mechanism remain unclear. In this study, we established a mouse model of S. japonicum infection, and the mice were randomly divided into uninfected, infected control, anti-CTLA-4 monoclonal antibody (anti-CTLA-4 mAb), GAPDH, and GAPDH combined with anti-CTLA-4 mAb groups to compare the protective effects against infection and the consequent tissue damage. The worm reduction rate in the GAPDH-treated infected mice was 26.58%, which increased to 54.61% when combined with anti-CTLA-4 mAb. The frequency of regulatory T cells (Tregs) was significantly higher in the anti-CTLA-4 mAb group and was lower in the GAPDH group. However, both anti-CTLA-4 mAb and GAPDH elevated the levels of the cytokines IFN-γ, IL-2, IL-4, and IL-5 in the spleens of infected mice, and their combination further enhanced cytokine production. The diameter of egg granuloma in the anti-CTLA-4 mAb group and combined treatment group increased significantly compared to that of the other groups. These results suggest that anti-CTLA-4 mAb can be used as an adjuvant to enhance the immune protection of the GAPDH vaccine via inducing the Th1 immune response, although this comes at the cost of enhanced body injury.


Assuntos
Antígenos de Helmintos/imunologia , Antígeno CTLA-4/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Vacinas/imunologia , Animais , Anticorpos Monoclonais/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Esquistossomose Japônica/parasitologia , Esquistossomose Japônica/prevenção & controle , Baço/imunologia , Linfócitos T Reguladores/imunologia
18.
Gastroenterology ; 157(3): 720-730.e2, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31175863

RESUMO

BACKGROUND & AIMS: Although pancreatic cystic lesions (PCLs) are frequently and incidentally detected, it is a challenge to determine their risk of malignancy. In immunohistochemical and enzyme-linked immunosorbent assay (ELISA) analyses of tissue and cyst fluid from pancreatic intraductal papillary mucinous neoplasms, the monoclonal antibody Das-1 identifies those at risk for malignancy with high levels of specificity and sensitivity. We aimed to validate the ability of Das-1 to identify high-risk PCLs in comparison to clinical guidelines and clinical features, using samples from a multicenter cohort. METHODS: We obtained cyst fluid samples of 169 PCLs (90 intraductal papillary mucinous neoplasms, 43 mucinous cystic neoplasms, and 36 non-mucinous cysts) from patients undergoing surgery at 4 tertiary referral centers (January 2010 through June 2017). Histology findings from surgical samples, analyzed independently and centrally re-reviewed in a blinded manner, were used as the reference standard. High-risk PCLs were those with invasive carcinomas, high-grade dysplasia, or intestinal-type intraductal papillary mucinous neoplasms with intermediate-grade dysplasia. An ELISA with Das-1 was performed in parallel using banked cyst fluid samples. We evaluated the biomarker's performance, generated area under the curve values, and conducted multivariate logistic regression using clinical and pathology features. RESULTS: The ELISA for Das-1 identified high-risk PCLs with 88% sensitivity, 99% specificity, and 95% accuracy, at a cutoff optical density value of 0.104. In 10-fold cross-validation analysis with 100 replications, Das-1 identified high-risk PCLs with 88% sensitivity and 98% specificity. The Sendai, Fukuoka, and American Gastroenterological Association guideline criteria identified high-risk PCLs with 46%, 52%, and 74% accuracy (P for comparison to Das-1 ELISA <.001). When we controlled for Das-1 in multivariate regression, main pancreatic duct dilation >5 mm (odds ratio, 14.98; 95% confidence interval, 2.63-108; P < .0012), main pancreatic duct dilation ≥1 cm (odds ratio, 47.9; 95% confidence interval, 6.39-490; P < .0001), and jaundice (odds ratio, 6.16; 95% confidence interval, 1.08-36.7; P = .0397) were significantly associated with high-risk PCLs. CONCLUSIONS: We validated the ability of an ELISA with the monoclonal antibody Das-1 to detect PCLs at risk for malignancy with high levels of sensitivity and specificity. This biomarker might be used in conjunction with clinical guidelines to identify patients at risk for malignancy.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos/análise , Biomarcadores Tumorais/análise , Ensaio de Imunoadsorção Enzimática , Neoplasias Císticas, Mucinosas e Serosas/química , Cisto Pancreático/química , Neoplasias Intraductais Pancreáticas/química , Neoplasias Pancreáticas/química , Adulto , Idoso , Anticorpos/imunologia , Especificidade de Anticorpos , Biomarcadores Tumorais/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Císticas, Mucinosas e Serosas/imunologia , Neoplasias Císticas, Mucinosas e Serosas/patologia , Neoplasias Císticas, Mucinosas e Serosas/cirurgia , Cisto Pancreático/imunologia , Cisto Pancreático/patologia , Cisto Pancreático/cirurgia , Neoplasias Intraductais Pancreáticas/imunologia , Neoplasias Intraductais Pancreáticas/patologia , Neoplasias Intraductais Pancreáticas/cirurgia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Medição de Risco , Estados Unidos
19.
Anal Chim Acta ; 1076: 154-161, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31203960

RESUMO

Cancer cell detection in liquid biopsies has been a widely studied application in many microfluidic devices. The use of a common antibody, such as the epithelial cell adhesion molecule (Anti-EpCAM) or other specific antibodies, has facilitated the detection and study of many cancers. However, the use of such antibodies requires a priori knowledge of the cancer source, and many cancer subtypes are missed in screening applications. There remains a need to study a wider range of cancers that maintain the streamlined antibody approach in cell affinity separations. The Human transferrin receptor (CD71) has recently been demonstrated as a cancer cell affinity target in blood samples. CD71 expression in blood cells is low, whereas proliferating cancer cells have a higher expression of the surface protein. CD71 expression is variable with cell cycle, which can impact cell separations. In this work, we investigated the effects of cell cycle and CD71 expression on cell capture metrics. Six cancer cell lines were isolated from blood via CD71 affinity capture, with a capture efficiency and purity that varied with CD71 expression. Despite variation in CD71 expression, the affinity was sufficient to isolate cancer cells spiked into blood; under optimal conditions, CD71-based capture resulted in capture purity >80%. We conclude that CD71 affinity separations show potential as a biomarker for cancer studies without sacrificing sensitivity and selectivity, and that cancer cells can be isolated from liquid biopsies over a range of expression of the target protein.


Assuntos
Antígenos CD/imunologia , Biomarcadores Tumorais/imunologia , Células Neoplásicas Circulantes/imunologia , Receptores da Transferrina/imunologia , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Dispositivos Lab-On-A-Chip , Ligantes , Biópsia Líquida , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
20.
Anal Chim Acta ; 1076: 91-99, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31203968

RESUMO

The development of an automated miniaturized analytical system that allows for the rapid monitoring of carbamazepine (CBZ) levels in serum and wastewater is proposed. Molecular recognition of CBZ was achieved through its selective interaction with microbeads carrying anti-CBZ antibodies. The proposed method combines the advantages of the micro-bead injection spectroscopy and of the flow-based platform lab-on-valve for implementation of automatic immunosorbent renewal, rendering a new recognition surface for each sample. The sequential (or simultaneous) perfusion of CBZ and the horseradish peroxidase-labelled CBZ through the microbeads is followed by real-time on-column monitoring of substrate (3,3',5,5'-tetramethylbenzidine) oxidation by colorimetry. The evaluation of the initial oxidation rate and also the absorbance value at a fixed time point provided a linear response versus the logarithm of the CBZ concentration. Under the selected assay conditions, a single analysis was completed after only 11 min, with a quantification range between 1.0 and 50 µg L-1. Detection of CBZ levels in undiluted wastewater samples was feasible after a simple filtration step while good recoveries were attained for spiked certified human serum, analyzed without sample clean-up.


Assuntos
Carbamazepina/sangue , Colorimetria/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Monoclonais/imunologia , Armoracia/enzimologia , Benzidinas/química , Carbamazepina/imunologia , Peroxidase do Rábano Silvestre/química , Humanos , Microesferas , Oxirredução , Sefarose/análogos & derivados , Sefarose/química , Águas Residuárias/análise
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