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1.
Genes Dev ; 32(5-6): 430-447, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29549180

RESUMO

The p53 tumor suppressor protein is the most well studied as a regulator of transcription in the nucleus, where it exists primarily as a tetramer. However, there are other oligomeric states of p53 that are relevant to its regulation and activities. In unstressed cells, p53 is normally held in check by MDM2 that targets p53 for transcriptional repression, proteasomal degradation, and cytoplasmic localization. Here we discovered a hydrophobic region within the MDM2 N-terminal domain that binds exclusively to the dimeric form of the p53 C-terminal domain in vitro. In cell-based assays, MDM2 exhibits superior binding to, hyperdegradation of, and increased nuclear exclusion of dimeric p53 when compared with tetrameric wild-type p53. Correspondingly, impairing the hydrophobicity of the newly identified N-terminal MDM2 region leads to p53 stabilization. Interestingly, we found that dimeric mutant p53 is partially unfolded and is a target for ubiquitin-independent degradation by the 20S proteasome. Finally, forcing certain tumor-derived mutant forms of p53 into dimer configuration results in hyperdegradation of mutant p53 and inhibition of p53-mediated cancer cell migration. Gaining insight into different oligomeric forms of p53 may provide novel approaches to cancer therapy.


Assuntos
Neoplasias/fisiopatologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Citoplasma/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Mutação , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Domínios Proteicos , Multimerização Proteica/genética , Proteólise , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética
2.
Anal Chem ; 96(14): 5509-5518, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551492

RESUMO

Micromotor (MM) technology offers a valuable and smart on-the-move biosensing microscale approach in clinical settings where sample availability is scarce in the case of Alzheimer's disease (AD). Soluble amyloid-ß protein oligomers (AßO) (mainly AßO42) that circulate in biological fluids have been recognized as a molecular biomarker and therapeutic target of AD due to their high toxicity, and they are correlated much more strongly with AD compared to the insoluble Aß monomers. A graphene oxide (GO)-gold nanoparticles (AuNPs)/nickel (Ni)/platinum nanoparticles (PtNPs) micromotors (MMGO-AuNPs)-based electrochemical label-free aptassay is proposed for sensitive, accurate, and rapid determination of AßO42 in complex clinical samples such as brain tissue, cerebrospinal fluid (CSF), and plasma from AD patients. An approach that implies the in situ formation of AuNPs on the GO external layer of tubular MM in only one step during MM electrosynthesis was performed (MMGO-AuNPs). The AßO42 specific thiolated-aptamer (AptAßO42) was immobilized in the MMGO-AuNPs via Au-S interaction, allowing for the selective recognition of the AßO42 (MMGO-AuNPs-AptAßO42-AßO42). AuNPs were smartly used not only to covalently bind a specific thiolated-aptamer for the design of a label-free electrochemical aptassay but also to improve the final MM propulsion performance due to their catalytic activity (approximately 2.0× speed). This on-the-move bioplatform provided a fast (5 min), selective, precise (RSD < 8%), and accurate quantification of AßO42 (recoveries 94-102%) with excellent sensitivity (LOD = 0.10 pg mL-1) and wide linear range (0.5-500 pg mL-1) in ultralow volumes of the clinical sample of AD patients (5 µL), without any dilution. Remarkably, our MM-based bioplatform demonstrated the competitiveness for the determination of AßO42 in the target samples against the dot blot analysis, which requires more than 14 h to provide qualitative results only. It is also important to highlight its applicability to the potential analysis of liquid biopsies as plasma and CSF samples, improving the reliability of the diagnosis given the heterogeneity and temporal complexity of neurodegenerative diseases. The excellent results obtained demonstrate the analytical potency of our approach as a future tool for clinical/POCT (Point-of-care testing) routine scenarios.


Assuntos
Doença de Alzheimer , Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Ouro/química , Peptídeos beta-Amiloides/análise , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Limite de Detecção , Platina , Proteínas Amiloidogênicas , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos
3.
Anal Chem ; 96(11): 4580-4588, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38348822

RESUMO

This work reports the first electrochemical bioplatforms developed for the determination of the total contents of either target miRNA or methylated target miRNA. The bioplatforms are based on the hybridization of the target miRNA with a synthetic biotinylated DNA probe, the capture of the formed DNA/miRNA heterohybrids on the surface of magnetic microcarriers, and their recognition with an antibody selective to these heterohybrids or to the N6-methyladenosine (m6A) epimark. The determination of the total or methylated target miRNA was accomplished by labeling such secondary antibodies with the horseradish peroxidase (HRP) enzyme. In both cases, amperometric transduction was performed on the surface of disposable electrodes after capturing the resulting HRP-tagged magnetic bioconjugates. Because of their increasing relevance in colorectal cancer (CRC) diagnosis and prognosis, miRNA let-7a and m6A methylation were selected. The proposed electrochemical bioplatforms showed attractive analytical and operational characteristics for the determination of the total and m6A-methylated target miRNA in less than 75 min. These bioplatforms, innovative in design and application, were applied to the analysis of total RNA samples extracted from cultured cancer cells with different metastatic profiles and from paired healthy and tumor tissues of patients diagnosed with CRC at different stages. The obtained results demonstrated, for the first time using electrochemical platforms, the potential of interrogating the target miRNA methylation level to discriminate the metastatic capacities of cancer cells and to identify tumor tissues and, in a pioneering way, the potential of the m6A methylation in miRNA let-7a to serve as a prognostic biomarker for CRC.


Assuntos
Técnicas Biossensoriais , Neoplasias Colorretais , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/análise , Epigenoma , Hibridização de Ácido Nucleico/métodos , Anticorpos/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Prognóstico , Técnicas Biossensoriais/métodos
4.
Int Arch Allergy Immunol ; : 1-7, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39137738

RESUMO

INTRODUCTION: Egg allergy usually manifests during the initial 2 years of life, a period in which most vaccinations are administered. This often leads to delays in the application of some vaccines in patients with egg allergies, exposing them to a risk of contracting preventable infections. The aim of the study was to describe the frequency of reactions after applying the yellow fever vaccine (YFV) within a population with egg allergy. METHODS: This was a cohort study with retrospective, multicenter data (2014-2023). Patient records diagnosed with egg allergy were gathered from their initial egg-related reactions until their YFV administration. Information was also collected about hypersensitivity tests conducted for egg and YFV such as the skin prick test (SPT) and intradermal test (IDT). RESULTS: Among the 171 records analyzed, 23.9% of patients had a history of egg anaphylaxis. Out of these, 5 patients had a positive SPT and 21 IDT with the YFV. All patients tolerated the application of YFV without developing hypersensitivity reactions, regardless of the results of the YFV tests, the severity of egg reactions, the number of egg reactions, or the time since the last egg reaction. Out of the total patient cohort, 46.1% (79 individuals) encountered delays in receiving the YFV, and in this subset, 14% faced delays lasting longer than 12 months. CONCLUSION: The risk of allergic reactions with the YFV remains low. YFV tests generate delays in the vaccine application without providing high diagnostic accuracy. YFV should not be deferred even in patients with a history of severe egg reactions.

5.
Cell Mol Life Sci ; 80(6): 141, 2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37149819

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive, chronic, and neurodegenerative disease, and the most common cause of dementia worldwide. Currently, the mechanisms underlying the disease are far from being elucidated. Thus, the study of proteins involved in its pathogenesis would allow getting further insights into the disease and identifying new markers for AD diagnosis. METHODS: We aimed here to analyze protein dysregulation in AD brain by quantitative proteomics to identify novel proteins associated with the disease. 10-plex TMT (tandem mass tags)-based quantitative proteomics experiments were performed using frozen tissue samples from the left prefrontal cortex of AD patients and healthy individuals and vascular dementia (VD) and frontotemporal dementia (FTD) patients as controls (CT). LC-MS/MS analyses were performed using a Q Exactive mass spectrometer. RESULTS: In total, 3281 proteins were identified and quantified using MaxQuant. Among them, after statistical analysis with Perseus (p value < 0.05), 16 and 155 proteins were defined as upregulated and downregulated, respectively, in AD compared to CT (Healthy, FTD and VD) with an expression ratio ≥ 1.5 (upregulated) or ≤ 0.67 (downregulated). After bioinformatics analysis, ten dysregulated proteins were selected as more prone to be associated with AD, and their dysregulation in the disease was verified by qPCR, WB, immunohistochemistry (IHC), immunofluorescence (IF), pull-down, and/or ELISA, using tissue and plasma samples of AD patients, patients with other dementias, and healthy individuals. CONCLUSIONS: We identified and validated novel AD-associated proteins in brain tissue that should be of further interest for the study of the disease. Remarkably, PMP2 and SCRN3 were found to bind to amyloid-ß (Aß) fibers in vitro, and PMP2 to associate with Aß plaques by IF, whereas HECTD1 and SLC12A5 were identified as new potential blood-based biomarkers of the disease.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/metabolismo , Demência Frontotemporal/genética , Proteômica , Cromatografia Líquida , Espectrometria de Massas em Tandem , Peptídeos beta-Amiloides/metabolismo , Córtex Pré-Frontal/metabolismo , Biomarcadores , Proteínas tau/metabolismo
6.
Mikrochim Acta ; 191(7): 369, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834823

RESUMO

A trendsetting direct competitive-based biosensing tool has been developed and implemented for the determination of the polyunsaturated fatty acid arachidonic acid (ARA), a highly significant biological regulator with decisive roles in viral infections. The designed methodology involves a competitive reaction between the target endogenous ARA and a biotin-ARA competitor for the recognition sites of anti-ARA antibodies covalently attached to the surface of carboxylic acid-coated magnetic microbeads (HOOC-MµBs), followed by the enzymatic label of the biotin-ARA residues with streptavidin-horseradish peroxidase (Strep-HRP) conjugate. The resulting bioconjugates were magnetically trapped onto the sensing surface of disposable screen-printed carbon transducers (SPCEs) to monitor the extent of the biorecognition reaction through amperometry. The operational functioning of the exhaustively optimized and characterized immunosensing bioplatform was highly convenient for the quantitative determination of ARA in serum samples from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2-) and respiratory syncytial virus (RSV)-infected individuals in a rapid, affordable, trustful, and sensitive manner.


Assuntos
Ácido Araquidônico , Técnicas Biossensoriais , COVID-19 , SARS-CoV-2 , Humanos , Ácido Araquidônico/sangue , COVID-19/sangue , COVID-19/diagnóstico , COVID-19/imunologia , Técnicas Biossensoriais/métodos , SARS-CoV-2/imunologia , Peroxidase do Rábano Silvestre/química , Vírus Sinciciais Respiratórios/imunologia , Imunoensaio/métodos , Estreptavidina/química , Biotina/química , Limite de Detecção
7.
Int J Mol Sci ; 25(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39000104

RESUMO

Cataracts and glaucoma account for a high percentage of vision loss and blindness worldwide. Small extracellular vesicles (sEVs) are released into different body fluids, including the eye's aqueous humor. Information about their proteome content and characterization in ocular pathologies is not yet well established. In this study, aqueous humor sEVs from healthy individuals, cataracts, and glaucoma patients were studied, and their specific protein profiles were characterized. Moreover, the potential of identified proteins as diagnostic glaucoma biomarkers was evaluated. The protein content of sEVs from patients' aqueous humor with cataracts and glaucoma compared to healthy individuals was analyzed by quantitative proteomics. Validation was performed by western blot (WB) and ELISA. A total of 828 peptides and 192 proteins were identified and quantified. After data analysis with the R program, 8 significantly dysregulated proteins from aqueous humor sEVs in cataracts and 16 in glaucoma showed an expression ratio ≥ 1.5. By WB and ELISA using directly aqueous humor samples, the dysregulation of 9 proteins was mostly confirmed. Importantly, GAS6 and SPP1 showed high diagnostic ability of glaucoma, which in combination allowed for discriminating glaucoma patients from control individuals with an area under the curve of 76.1% and a sensitivity of 65.6% and a specificity of 87.7%.


Assuntos
Humor Aquoso , Biomarcadores , Catarata , Vesículas Extracelulares , Glaucoma , Peptídeos e Proteínas de Sinalização Intercelular , Osteopontina , Proteômica , Humanos , Humor Aquoso/metabolismo , Humor Aquoso/química , Glaucoma/metabolismo , Glaucoma/diagnóstico , Vesículas Extracelulares/metabolismo , Biomarcadores/metabolismo , Proteômica/métodos , Feminino , Masculino , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/análise , Idoso , Osteopontina/metabolismo , Pessoa de Meia-Idade , Catarata/metabolismo , Catarata/diagnóstico , Proteoma/análise , Proteoma/metabolismo , Ensaio de Imunoadsorção Enzimática
8.
Brain Behav Immun ; 113: 44-55, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37406976

RESUMO

BACKGROUND: Multiple sclerosis (MS) is an immune-mediated central nervous system disease whose course is unpredictable. Finding biomarkers that help to better comprehend the disease's pathogenesis is crucial for supporting clinical decision-making. Blood extracellular vesicles (EVs) are membrane-bound particles secreted by all cell types that contain information on the disease's pathological processes. PURPOSE: To identify the immune and nervous system-derived EV profile from blood that could have a specific role as biomarker in MS and assess its possible correlation with disease state. RESULTS: Higher levels of T cell-derived EVs and smaller size of neuron-derived EVs were associated with clinical relapse. The smaller size of the oligodendrocyte-derived EVs was related with motor and cognitive impairment. The proteomic analysis identified mannose-binding lectin serine protease 1 and complement factor H from immune system cell-derived EVs as autoimmune disease-associated proteins. We observed hepatocyte growth factor-like protein in EVs from T cells and inter-alpha-trypsin inhibitor heavy chain 2 from neurons as white matter injury-related proteins. In patients with MS, a specific protein profile was found in the EVs, higher levels of alpha-1-microglobulin and fibrinogen ß chain, lower levels of C1S and gelsolin in the immune system-released vesicles, and Talin-1 overexpression in oligodendrocyte EVs. These specific MS-associated proteins, as well as myelin basic protein in oligodendrocyte EVs, correlated with disease activity in the patients with MS. CONCLUSION: Neural-derived and immune-derived EVs found in blood appear to be good specific biomarkers in MS for reflecting the disease state.


Assuntos
Vesículas Extracelulares , Esclerose Múltipla , Humanos , Esclerose Múltipla/metabolismo , Proteômica , Encéfalo/patologia , Vesículas Extracelulares/metabolismo , Sistema Imunitário , Matriz Extracelular , Biomarcadores
9.
Anal Bioanal Chem ; 415(11): 2045-2057, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36344668

RESUMO

The glycosylation status of proteins is increasingly used as biomarker to improve the reliability in the diagnosis and prognosis of diseases as relevant as cancer. This feeds the need for tools that allow its simple and reliable analysis and are compatible with applicability in the clinic. With this objective in mind, this work reports the first bioelectronic immunoplatforms described to date for the determination of glycosylated haptoglobin (Hp) and the simultaneous determination of total and glycosylated Hp. The bioelectronic immunoplatform is based on the implementation of non-competitive bioassays using two different antibodies or an antibody and a lectin on the surface of commercial magnetic microcarriers. The resulting bioconjugates are labeled with the horseradish peroxidase (HRP) enzyme, and after their magnetic capture on disposable electroplatforms, the amperometric transduction using the H2O2/hydroquinone (HQ) system allows the single or multiple detection. The developed immunoplatform achieves limits of detection (LODs) of 0.07 and 0.46 ng mL-1 for total and glycosylated Hp in buffer solution, respectively. The immunoplatform allows accurate determination using simple and relatively short protocols (approx. 75 min) of total and glycosylated Hp in the secretomes of in vitro-cultured colorectal cancer (CRC) cells with different metastatic potentials, which is not feasible, due to lack of sensitivity, by means of some commercial ELISA kits and Western blot methodology.


Assuntos
Técnicas Biossensoriais , Neoplasias , Humanos , Haptoglobinas , Peróxido de Hidrogênio , Reprodutibilidade dos Testes , Ensaio de Imunoadsorção Enzimática , Anticorpos , Técnicas Biossensoriais/métodos
10.
Br J Cancer ; 126(11): 1604-1615, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35347323

RESUMO

BACKGROUND: Liver metastasis is the primary cause of colorectal cancer (CRC)-associated death. Aryl-hydrocarbon receptor-interacting protein (AIP), a putative positive intermediary in aryl-hydrocarbon receptor-mediated signalling, is overexpressed in highly metastatic human KM12SM CRC cells and other highly metastatic CRC cells. METHODS: Meta-analysis and immunohistochemistry were used to assess the relevance of AIP. Cellular functions and signalling mechanisms mediated by AIP were assessed by gain-of-function experiments and in vitro and in vivo experiments. RESULTS: A significant association of high AIP expression with poor CRC patients' survival was observed. Gain-of-function and quantitative proteomics experiments demonstrated that AIP increased tumorigenic and metastatic properties of isogenic KM12C (poorly metastatic) and KM12SM (highly metastatic to the liver) CRC cells. AIP overexpression dysregulated epithelial-to-mesenchymal (EMT) markers and induced several transcription factors and Cadherin-17 activation. The former induced the signalling activation of AKT, SRC and JNK kinases to increase adhesion, migration and invasion of CRC cells. In vivo, AIP expressing KM12 cells induced tumour growth and liver metastasis. Furthermore, KM12C (poorly metastatic) cells ectopically expressing AIP became metastatic to the liver. CONCLUSIONS: Our data reveal new roles for AIP in regulating proteins associated with cancer and metastasis to induce tumorigenic and metastatic properties in colon cancer cells driving liver metastasis.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Retais , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Hidrocarbonetos , Imuno-Histoquímica , Neoplasias Hepáticas/secundário , Metástase Neoplásica
11.
Anal Bioanal Chem ; 414(1): 399-412, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33635388

RESUMO

Metastasis is responsible for about 90% of cancer-associated deaths. In the context of solid tumors, the low oxygen concentration in the tumor microenvironment (hypoxia) is one of the key factors contributing to metastasis. Tumor cells adapt to these conditions by overexpressing certain proteins such as programmed death ligand 1 (PD-L1) and hypoxia-inducible factor 1 alpha (HIF-1α). However, the determination of these tumor hypoxia markers that can be used to follow-up tumor progression and improve the efficiency of therapies has been scarcely addressed using electrochemical biosensors. In this work, we report the first electrochemical bioplatform for the determination of PD-L1 as well as the first one allowing its simultaneous determination with HIF-1α. The target proteins were captured and enzymatically labeled on magnetic microbeads and amperometric detection was undertaken on the surface of screen-printed dual carbon electrodes using the hydrogen peroxide/peroxidase/hydroquinone system. Sandwich immunoassays were implemented for both the HIF-1α and PD-L1 sensors and the analytical characteristics were evaluated providing LOD values of 86 and 279 pg mL-1 for the amperometric determination of PD-L1 and HIF-1α standards, respectively. The developed electrochemical immunoplatforms are competitive versus the only electrochemical immunosensor reported for the determination of HIF-1α and the "gold standard" ELISA methodology for the single determination of both proteins in terms of assay time, compatibility with the simultaneous determination of both proteins making their use suitable for untrained users at the point of attention. The dual amperometric immunosensor was applied to the simultaneous determination of HIF-1α and PD-L1 in cancer cell lysates. The analyses lasted only 2 h and just 0.5 µg of the sample was required.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos , Humanos , Hipóxia , Imunoensaio , Hipóxia Tumoral
12.
Mikrochim Acta ; 189(4): 143, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35286499

RESUMO

A dual immunosensor is reported for the simultaneous determination of two important immunity-related cytokines: BAFF (B cell activation factor) and APRIL (a proliferation-induced signal). Sandwich-type immunoassays with specific antibodies (cAbs) and a strategy for signal amplification based on labelling the detection antibodies (dAbs) with binary MoS2/MWCNTs nanostructures and using horseradish peroxidase (HRP) were implemented. Amperometric detection was carried out at screen-printed dual carbon electrodes (SPdCEs) through the hydroquinone HQ/H2O2 system. The developed dual immunosensor provided limit of detection (LOD) of 0.08 and 0.06 ng mL-1 for BAFF and APRIL, respectively, and proved to be useful for the determination of both cytokines in cancer cell lysates and serum samples from patients diagnosed with autoimmune diseases and cancer. The obtained results agreed with those found using ELISA methodologies.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Anticorpos , Técnicas Biossensoriais/métodos , Proliferação de Células , Citocinas , Técnicas Eletroquímicas , Humanos , Peróxido de Hidrogênio , Imunoensaio/métodos , Molibdênio
13.
Angew Chem Int Ed Engl ; 61(28): e202203662, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35507573

RESUMO

The development of versatile and sensitive biotools to quantify specific SARS-CoV-2 immunoglobulins in SARS-CoV-2 infected and non-infected individuals, built on the surface of magnetic microbeads functionalized with nucleocapsid (N) and in-house expressed recombinant spike (S) proteins is reported. Amperometric interrogation of captured N- and S-specific circulating total or individual immunoglobulin (Ig) isotypes (IgG, IgM, and IgA), subsequently labelled with HRP-conjugated secondary antibodies, was performed at disposable single or multiplexed (8×) screen-printed electrodes using the HQ/HRP/H2 O2 system. The obtained results using N and in-house expressed S ectodomains of five SARS-CoV-2 variants of concern (including the latest Delta and Omicron) allow identification of vulnerable populations from those with natural or acquired immunity, monitoring of infection, evaluation of vaccine efficiency, and even identification of the variant responsible for the infection.


Assuntos
Técnicas Biossensoriais , COVID-19 , Anticorpos Antivirais , COVID-19/diagnóstico , Teste para COVID-19 , Humanos , Imunidade , Imunoglobulina G , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
14.
J Proteome Res ; 20(11): 5115-5130, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34628858

RESUMO

New biomarkers of Alzheimer's disease (AD) with a diagnostic value in preclinical and prodromal stages are urgently needed. AD-related serum autoantibodies are potential candidate biomarkers. Here, we aimed at identifying AD-related serum autoantibodies using protein microarrays and mass spectrometry-based methods. To this end, an untargeted complementary screening using high-density (42,100 antigens) and low-density (384 antigens) planar protein-epitope signature tag (PrEST) arrays and an immunoprecipitation protocol coupled to mass spectrometry analysis were used for serum autoantibody profiling. From the untargeted screening phase, 377 antigens corresponding to 338 proteins were selected for validation. Out of them, IVD, CYFIP1, and ADD2 seroreactivity was validated using 128 sera from AD patients and controls by PrEST-suspension bead arrays, and ELISA or luminescence Halotag-based bead immunoassay using full-length recombinant proteins. Importantly, IVD, CYFIP1, and ADD2 showed in combination a noticeable AD diagnostic ability. Moreover, IVD protein abundance in the prefrontal cortex was significantly two-fold higher in AD patients than in controls by western blot and immunohistochemistry, whereas CYFIP1 and ADD2 were significantly down-regulated in AD patients. The panel of AD-related autoantigens identified by a comprehensive multiomics approach may provide new insights of the disease and should help in the blood-based diagnosis of Alzheimer's disease. Mass spectrometry raw data are available in the ProteomeXchange database with the access number PXD028392.


Assuntos
Doença de Alzheimer , Autoanticorpos , Autoantígenos , Biomarcadores , Humanos , Análise Serial de Proteínas/métodos
15.
Anal Bioanal Chem ; 413(3): 799-811, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32474723

RESUMO

Early diagnosis in primary care settings can increase access to therapies and their efficiency as well as reduce health care costs. In this context, we report in this paper the development of a disposable immunoplatform for the rapid and simultaneous determination of two protein biomarkers recently reported to be involved in the pathological process of neurodegenerative disorders (NDD), tau protein (tau), and TAR DNA-binding protein 43 (TDP-43). The methodology involves implementation of a sandwich-type immunoassay on the surface of dual screen-printed carbon electrodes (dSPCEs) electrochemically grafted with p-aminobenzoic acid (p-ABA), which allows the covalent immobilization of a gold nanoparticle-poly(amidoamine) (PAMAM) dendrimer nanocomposite (3D-Au-PAMAM). This scaffold was employed for the immobilization of the capture antibodies (CAbs). Detector antibodies labeled with horseradish peroxidase (HRP) and amperometric detection at - 0.20 V (vs. Ag pseudo-reference electrode) using the H2O2/hydroquinone (HQ) system were used. The developed methodology exhibits high sensitivity and selectivity for determining the target proteins, with detection limits of 2.3 and 12.8 pg mL-1 for tau and TDP-43, respectively. The simultaneous determination of tau and TDP-43 was accomplished in raw plasma samples and brain tissue extracts from healthy individuals and NDD-diagnosed patients. The analysis can be performed in just 1 h using a simple one-step assay protocol and small sample amounts (5 µL plasma and 2.5 µg brain tissue extracts). Graphical abstract.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Dendrímeros/química , Ouro/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Doenças Neurodegenerativas/diagnóstico , Poliaminas/química , Proteínas tau/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Encéfalo/metabolismo , Estudos de Casos e Controles , Proteínas de Ligação a DNA/sangue , Eletrodos , Humanos , Doenças Neurodegenerativas/sangue , Doenças Neurodegenerativas/metabolismo , Proteínas tau/sangue
16.
Anal Bioanal Chem ; 412(24): 6177-6188, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31989193

RESUMO

Proteases are involved in cancer' taking part in immune (dis)regulation, malignant progression and tumour growth. Recently, it has been found that expression levels of one of the members of the serine protease family, trypsin, is upregulated in human cancer cells of several organs, being considered as a specific cancer biomarker. Considering the great attention that electrochemical peptide sensors have nowadays, in this work, we propose a novel electroanalytical strategy for the determination of this important biomolecule. It implies the immobilization of a short synthetic peptide sequence, dually labelled with fluorescein isothiocyanate (FITC) and biotin, onto neutravidin-modified magnetic beads (MBs), followed by the peptide digestion with trypsin. Upon peptide disruption, the modified MBs were incubated with a specific fluorescein Fab fragment antibody labelled with horseradish peroxidase (HRP-antiFITC) and magnetically captured on the surface of a screen-printed carbon electrode (SPCE), where amperometric detection was performed using the hydroquinone (HQ)/HRP/H2O2 system. The biosensor exhibited a good reproducibility of the measurements (RSD 3.4%, n = 10), and specificity against other proteins and proteases commonly found in biological samples. This work reports the first quantitative data so far on trypsin expression in human cell lysates. The developed bioplatform was used for the direct determination of this protease in lysates from pancreatic cancer, cervix carcinoma and kidney cells in only 3 h and 30 min using low amounts (~ 0.1 µg) of raw extracts. Graphical abstract.


Assuntos
Técnicas Eletroquímicas/métodos , Metástase Neoplásica , Neoplasias Pancreáticas/enzimologia , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Técnicas Biossensoriais , Calibragem , Humanos , Oxirredução , Neoplasias Pancreáticas/patologia , Reprodutibilidade dos Testes
17.
J Proteome Res ; 18(7): 2940-2953, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31136180

RESUMO

The characterization of the humoral response in Alzheimer's disease (AD) patients might aid in detecting the disease at early stages. We have combined phage display and protein microarrays to identify AD autoantibodies and their target biomarkers. After enrichment of the T7 phage display libraries from AD and healthy brain tissue mRNA in AD-specific phages, 1536 monoclonal phages were printed on microarrays to probe them with 8 AD and 8 healthy control sera. A total of 57 phages showed higher seroreactivity in AD. In total, 13 out of the 44 unique sequences displayed on the phages were selected for validation using 68 AD and 52 healthy control sera. Peptides from Anthrax toxin receptor 1, Nuclear protein 1, Glycogen phosphorylase, and Olfactory receptor 8J1 expressed in bacteria as HaloTag fusion proteins showed a statistically significant ability to discriminate between AD patients and controls. The identified panel of AD autoantibodies might provide new insights into the blood-based diagnosis of the disease.


Assuntos
Doença de Alzheimer/imunologia , Autoanticorpos/análise , Doença de Alzheimer/diagnóstico , Bacteriófagos/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Humanos , Peptídeos/genética , Análise Serial de Proteínas/métodos
18.
Immunotherapy ; 16(9): 623-634, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39052282

RESUMO

Aim: To evaluate the criteria used by allergists in selecting an immunotherapy extract (allergen immunotherapy [AIT]-extract) in rhinitis patients with polysensitization. Methods: First, a cross-sectional study was carried out by evaluating different factors that influence the medical choice of AIT-extract. Second, a literature review was performed by evaluating the diagnostic performance of atopy tests. Results: A total of 419 patients were included (84 children, 149 adolescents and 186 adults). Anamnesis, atopy tests and exposure to pets were the main factors for choosing the AIT extract. The sensitivity and specificity of atopy tests were high for Dermatophagoides spp., (>80%), moderate for pets (60%) and indeterminate for Blomia tropicalis. Conclusion: NCTs could be necessary for AIT-extract selection in polysensitized allergic rhinitis patients.


Allergen immunotherapy is an effective treatment for patients with allergic rhinitis. Atopy tests are used to identify possible substances in the environment that cause symptoms. A patient may sometimes have multiple substances which could be causing their allergic reactions, which makes it difficult to choose the appropriate immunotherapy for the patient. In this study, we identified some factors that might help to guide the criteria used by allergists when selecting the extract for immunotherapy.


Assuntos
Alérgenos , Dessensibilização Imunológica , Rinite Alérgica , Humanos , Adolescente , Dessensibilização Imunológica/métodos , Criança , Alérgenos/imunologia , Estudos Transversais , Rinite Alérgica/imunologia , Rinite Alérgica/terapia , Adulto , Feminino , Masculino , Animais , Adulto Jovem , Pessoa de Meia-Idade , Pré-Escolar
19.
Mol Cell Biol ; 44(1): 27-42, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38270135

RESUMO

The p63 transcription factor, a member of the p53 family, plays an oncogenic role in squamous cell carcinomas, while in breast cancers its expression is often repressed. In the canonical conserved Hippo pathway, known to play a complex role in regulating growth of cancer cells, protein kinases MST1/2 and LATS1/2 act sequentially to phosphorylate and inhibit the YAP/TAZ transcription factors. We found that in MCF10A mammary epithelial cells as well as in squamous and breast cancer cell lines, expression of ΔNp63 RNA and protein is strongly repressed by inhibition of the Hippo pathway protein kinases. While MST1/2 and LATS1 are required for p63 expression, the next step of the pathway, namely phosphorylation and degradation of the YAP/TAZ transcriptional activators is not required for p63 repression. This suggests that regulation of p63 expression occurs by a noncanonical version of the Hippo pathway. We identified similarly regulated genes, suggesting the broader importance of this pathway. Interestingly, lowering p63 expression lead to increased YAP protein levels, indicating crosstalk of the YAP/TAZ-independent and -dependent branches of the Hippo pathway. These results, which reveal the intersection of the Hippo and p63 pathways, may prove useful for the control of their activities in cancer cells.


Assuntos
Via de Sinalização Hippo , Transdução de Sinais , Humanos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Sinalização YAP , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo
20.
Front Immunol ; 15: 1455602, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234247

RESUMO

Although blood autoantibodies were initially associated with autoimmune diseases, multiple evidence have been accumulated showing their presence in many types of cancer. This has opened their use in clinics, since cancer autoantibodies might be useful for early detection, prognosis, and monitoring of cancer patients. In this review, we discuss the different techniques available for their discovery and validation. Additionally, we discuss here in detail those autoantibody panels verified in at least two different reports that should be more likely to be specific of each of the four most incident cancers. We also report the recent developed kits for breast and lung cancer detection mostly based on autoantibodies and the identification of novel therapeutic targets because of the screening of the cancer humoral immune response. Finally, we discuss unsolved issues that still need to be addressed for the implementation of cancer autoantibodies in clinical routine for cancer diagnosis, prognosis, and/or monitoring.


Assuntos
Autoanticorpos , Biomarcadores Tumorais , Neoplasias , Humanos , Autoanticorpos/imunologia , Autoanticorpos/sangue , Neoplasias/imunologia , Neoplasias/diagnóstico , Biomarcadores Tumorais/imunologia , Prognóstico , Detecção Precoce de Câncer , Animais
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