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1.
Cytometry A ; 101(11): 909-921, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35150047

RESUMO

Barcoded flow cytometry is a multiplexing technique allowing for the simultaneous acquisition of cells from different donors or experimental conditions in a high-throughput manner. This approach allows to synchronize acquisition of samples and reduce variance introduced through the operator or technical platform. However, to date, only very few flow cytometry barcoding protocols have been developed, which often suffer from technical limitations. Here, we developed a novel barcoding protocol for a full-spectrum flow cytometry platform. We developed a 21-color immunophenotyping assay for up to 20 different samples analyzed simultaneously with comparable variance between repeated single-tube acquisition and postde-multiplexing. Barcoding offers great potential in parallelizing the analysis of complex cell populations such as peripheral blood mononuclear cells (PBMCs). Consequently, we assessed the performance of our method in situations where PBMCs were challenged with phytohaemagglutinin (PHA), a strong mitogen and broad activator of B cells and T cells, and superantigen Staphylococcus enterotoxin B (SEB) that has been reported to induce polyclonal T cell activation. PBMCs were either barcoded before pooled challenge or challenged individually pre-barcoding. Our final workflow included pooled immunophenotyping followed by machine learning aided single-cell data analysis and enabled us to identify robust PHA and SEB mode of action related phenotypic changes in PBMC immune cell lineages. Conclusively, we present a novel technique allowing the barcoded acquisition and analysis of PBMCs from up to 20 different donors and present a valid basis for the future development of complex immunophenotyping protocols.


Assuntos
Leucócitos Mononucleares , Análise de Célula Única , Imunofenotipagem , Citometria de Fluxo/métodos , Análise de Célula Única/métodos , Fenótipo
2.
Cytometry A ; 99(8): 832-843, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33704890

RESUMO

Receptor occupancy (RO) assessment by flow cytometry is an important pharmacodynamic (PD) biomarker in the clinical development of large molecules such as monoclonal therapeutic antibodies (mAbs). The total-drug-bound RO assay format directly assesses mAb binding to cell surface targets using anti-drug detection antibodies. Here, we generated a flow cytometry detection antibody specifically binding to mAbs of the IgG1 P329GLALA backbone. Using this reagent, we developed a total-drug-bound RO assay format for RG7769, a bi-specific P329GLALA containing mAb targeting PD-1 and TIM3 on T cells. In its fit-for-purpose validated version, this RO assay has been used in the Phase-I dose escalation study of RG7769, informing on peripheral T cell RO and RG7769 antibody binding capacity (ABC). We assessed RG7769 RO in checkpoint-inhibitor (CPI) naïve patients and anti-PD-1 CPI experienced patients using our novel assay. Here, we show that in both groups, complete T cell RO can be achieved (~100%). However, we found that the maximum number of T cell binding sites for RG7769 pre-dosing was roughly twofold lower in patients recently having undergone anti-PD-1 treatment. We show that this is due to steric hindrance exerted by competing mAbs masking the available drug binding sites. Our findings highlight the importance of quantitative mAb assessment in addition to relative RO especially in the context of patients who have previously received anti-PD-1 treatment.


Assuntos
Anticorpos Monoclonais , Bioensaio , Biomarcadores , Citometria de Fluxo , Humanos
3.
Clin Infect Dis ; 65(7): 1103-1111, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575239

RESUMO

Background: Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects 10 million people worldwide. Approximately 12000 deaths attributable to Chagas disease occur annually due to chronic Chagas disease cardiomyopathy (CCC), an inflammatory cardiomyopathy presenting with heart failure and arrythmia; 30% of infected subjects develop CCC years after infection. Genetic mechanisms play a role in differential progression to CCC, but little is known about the role of epigenetic modifications in pathological gene expression patterns in CCC patients' myocardium. DNA methylation is the most common modification in the mammalian genome. Methods: We investigated the impact of genome-wide cardiac DNA methylation on global gene expression in myocardial samples from end-stage CCC patients, compared to control samples from organ donors. Results: In total, 4720 genes were differentially methylated between CCC patients and controls, of which 399 were also differentially expressed. Several of them were related to heart function or to the immune response and had methylation sites in their promoter region. Reporter gene and in silico transcription factor binding analyses indicated promoter methylation modified expression of key genes. Among those, we found potassium channel genes KCNA4 and KCNIP4, involved in electrical conduction and arrythmia, SMOC2, involved in matrix remodeling, as well as enkephalin and RUNX3, potentially involved in the increased T-helper 1 cytokine-mediated inflammatory damage in heart. Conclusions: Results support that DNA methylation plays a role in the regulation of expression of pathogenically relevant genes in CCC myocardium, and identify novel potential disease pathways and therapeutic targets in CCC.


Assuntos
Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Metilação de DNA/genética , Adolescente , Adulto , Idoso , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/parasitologia , Doença Crônica , Impressões Digitais de DNA/métodos , Feminino , Expressão Gênica/genética , Coração/parasitologia , Humanos , Inflamação/genética , Inflamação/parasitologia , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Canais de Potássio/genética , Regiões Promotoras Genéticas/genética , Trypanosoma cruzi/patogenicidade , Adulto Jovem
4.
J Infect Dis ; 214(1): 161-5, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-26951817

RESUMO

Long noncoding RNAs (lncRNAs) modulate gene expression at the epigenetic, transcriptional, and posttranscriptional levels. Dysregulation of the lncRNA known as myocardial infarction-associated transcript (MIAT) has been associated with myocardial infarction. Chagas disease causes a severe inflammatory dilated chronic cardiomyopathy (CCC). We investigated the role of MIAT in CCC. A whole-transcriptome analysis of heart biopsy specimens and formalin-fixed, paraffin-embedded samples revealed that MIAT was overexpressed in patients with CCC, compared with subjects with noninflammatory dilated cardiomyopathy and controls. These results were confirmed in a mouse model. Results suggest that MIAT is a specific biomarker of CCC.


Assuntos
Doença de Chagas/complicações , Doença de Chagas/genética , Perfilação da Expressão Gênica , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/genética , RNA Longo não Codificante , Animais , Doença de Chagas/fisiopatologia , Feminino , Humanos , Masculino , Camundongos , Fatores de Transcrição
5.
J Biol Chem ; 289(41): 28249-59, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25170076

RESUMO

Autoantibodies to apolipoprotein A-I (anti-apoA-I IgG) have been shown to be both markers and mediators of cardiovascular disease, promoting atherogenesis and unstable atherosclerotic plaque. Previous studies have shown that high levels of anti-apoA-I IgGs are independently associated with major adverse cardiovascular events in patients with myocardial infarction. Autoantibody responses to apoA-I can be polyclonal and it is likely that more than one epitope may exist. To identify the specific immunoreactive peptides in apoA-I, we have developed a set of methodologies and procedures to isolate, purify, and identify novel apoA-I endogenous epitopes. First, we generated high purity apoA-I from human plasma, using thiophilic interaction chromatography followed by enzymatic digestion specifically at lysine or arginine residues. Immunoreactivity to the different peptides generated was tested by ELISA using serum obtained from patients with acute myocardial infarction and high titers of autoantibodies to native apoA-I. The immunoreactive peptides were further sequenced by mass spectrometry. Our approach successfully identified two novel immunoreactive peptides, recognized by autoantibodies from patients suffering from myocardial infarction, who contain a high titer of anti-apoA-I IgG. The discovery of these epitopes may open innovative prognostic and therapeutic opportunities potentially suitable to improve current cardiovascular risk stratification.


Assuntos
Apolipoproteína A-I/química , Aterosclerose/imunologia , Autoanticorpos/sangue , Epitopos/química , Infarto do Miocárdio/imunologia , Placa Aterosclerótica/imunologia , Sequência de Aminoácidos , Apolipoproteína A-I/imunologia , Autoanticorpos/biossíntese , Biomarcadores/análise , Cromatografia de Afinidade , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Expressão Gênica , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Dados de Sequência Molecular , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/patologia , Peptídeos/química , Peptídeos/imunologia , Placa Aterosclerótica/sangue , Placa Aterosclerótica/diagnóstico , Placa Aterosclerótica/patologia , Análise de Sequência de Proteína
6.
Bioanalysis ; 15(15): 861-903, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37584363

RESUMO

The 16th Workshop on Recent Issues in Bioanalysis (16th WRIB) took place in Atlanta, GA, USA on September 26-30, 2022. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 16th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on ICH M10 BMV final guideline (focused on this guideline training, interpretation, adoption and transition); mass spectrometry innovation (focused on novel technologies, novel modalities, and novel challenges); and flow cytometry bioanalysis (rising of the 3rd most common/important technology in bioanalytical labs) were the special features of the 16th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2022 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2022 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers the recommendations on LBA, Biomarkers/CDx and Cytometry. Part 1 (Mass Spectrometry and ICH M10) and Part 3 (Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity) are published in volume 15 of Bioanalysis, issues 16 and 14 (2023), respectively.


Assuntos
Bioensaio , Relatório de Pesquisa , Citometria de Fluxo/métodos , Ligantes , Biomarcadores/análise , Bioensaio/métodos
7.
Cytometry B Clin Cytom ; 102(3): 220-227, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35253974

RESUMO

BACKGROUND: A key step in clinical flow cytometry data analysis is gating, which involves the identification of cell populations. The process of gating produces a set of reportable results, which are typically described by gating definitions. The non-standardized, non-interpreted nature of gating definitions represents a hurdle for data interpretation and data sharing across and within organizations. Interpreting and standardizing gating definitions for subsequent analysis of gating results requires a curation effort from experts. Machine learning approaches have the potential to help in this process by predicting expert annotations associated with gating definitions. METHODS: We created a gold-standard dataset by manually annotating thousands of gating definitions with cell type and functional marker annotations. We used this dataset to train and test a machine learning pipeline able to predict standard cell types and functional marker genes associated with gating definitions. RESULTS: The machine learning pipeline predicted annotations with high accuracy for both cell types and functional marker genes. Accuracy was lower for gating definitions from assays belonging to laboratories from which limited or no prior data was available in the training. Manual error review ensured that resulting predicted annotations could be reused subsequently as additional gold-standard training data. CONCLUSIONS: Machine learning methods are able to consistently predict annotations associated with gating definitions from flow cytometry assays. However, a hybrid automatic and manual annotation workflow would be recommended to achieve optimal results.


Assuntos
Aprendizado de Máquina , Citometria de Fluxo , Humanos , Fluxo de Trabalho
8.
Front Cell Infect Microbiol ; 12: 836242, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372112

RESUMO

Chronic Chagas disease (CCC) is an inflammatory dilated cardiomyopathy with a worse prognosis compared to other cardiomyopathies. We show the expression and activity of Matrix Metalloproteinases (MMP) and of their inhibitors TIMP (tissue inhibitor of metalloproteinases) in myocardial samples of end stage CCC, idiopathic dilated cardiomyopathy (DCM) patients, and from organ donors. Our results showed significantly increased mRNA expression of several MMPs, several TIMPs and EMMPRIN in CCC and DCM samples. MMP-2 and TIMP-2 protein levels were significantly elevated in both sample groups, while MMP-9 protein level was exclusively increased in CCC. MMPs 2 and 9 activities were also exclusively increased in CCC. Results suggest that the balance between proteins that inhibit the MMP-2 and 9 is shifted toward their activation. Inflammation-induced increases in MMP-2 and 9 activity and expression associated with imbalanced TIMP regulation could be related to a more extensive heart remodeling and poorer prognosis in CCC patients.


Assuntos
Cardiomiopatia Dilatada , Cardiomiopatia Chagásica , Cardiomiopatia Dilatada/metabolismo , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Miocárdio
9.
Front Immunol ; 13: 1020572, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248819

RESUMO

Chagas disease is a parasitic disease from South America, affecting around 7 million people worldwide. Decades after the infection, 30% of people develop chronic forms, including Chronic Chagas Cardiomyopathy (CCC), for which no treatment exists. Two stages characterized this form: the moderate form, characterized by a heart ejection fraction (EF) ≥ 0.4, and the severe form, associated to an EF < 0.4. We propose two sets of DNA methylation biomarkers which can predict in blood CCC occurrence, and CCC stage. This analysis, based on machine learning algorithms, makes predictions with more than 95% accuracy in a test cohort. Beyond their predictive capacity, these CpGs are located near genes involved in the immune response, the nervous system, ion transport or ATP synthesis, pathways known to be deregulated in CCCs. Among these genes, some are also differentially expressed in heart tissues. Interestingly, the CpGs of interest are tagged to genes mainly involved in nervous and ionic processes. Given the close link between methylation and gene expression, these lists of CpGs promise to be not only good biomarkers, but also good indicators of key elements in the development of this pathology.


Assuntos
Cardiomiopatia Chagásica , Doença de Chagas , Trifosfato de Adenosina/metabolismo , Biomarcadores/metabolismo , Cardiomiopatia Chagásica/diagnóstico , Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Metilação de DNA , Humanos
10.
Bioanalysis ; 14(10): 627-692, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35578974

RESUMO

The 15th edition of the Workshop on Recent Issues in Bioanalysis (15th WRIB) was held on 27 September to 1 October 2021. Even with a last-minute move from in-person to virtual, an overwhelmingly high number of nearly 900 professionals representing pharma and biotech companies, contract research organizations (CROs), and multiple regulatory agencies still eagerly convened to actively discuss the most current topics of interest in bioanalysis. The 15th WRIB included three Main Workshops and seven Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on biomarker assay development and validation (BAV) (focused on clarifying the confusion created by the increased use of the term "context of use" [COU]); mass spectrometry of proteins (therapeutic, biomarker and transgene); state-of-the-art cytometry innovation and validation; and critical reagent and positive control generation were the special features of the 15th edition. This 2021 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2021 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers the recommendations on ISR for Biomarkers, Liquid Biopsies, Spectral Cytometry, Inhalation/Oral & Multispecific Biotherapeutics, Accuracy/LLOQ for Flow Cytometry. Part 1A (Endogenous Compounds, Small Molecules, Complex Methods, Regulated Mass Spec of Large Molecules, Small Molecule, PoC), Part 1B (Regulatory Agencies' Inputs on Bioanalysis, Biomarkers, Immunogenicity, Gene & Cell Therapy and Vaccine) and Part 3 (TAb/NAb, Viral Vector CDx, Shedding Assays; CRISPR/Cas9 & CAR-T Immunogenicity; PCR & Vaccine Assay Performance; ADA Assay Comparability & Cut Point Appropriateness) are published in volume 14 of Bioanalysis, issues 9 and 11 (2022), respectively.


Assuntos
Citometria de Fluxo , Biomarcadores/análise , Citometria de Fluxo/métodos , Humanos , Indicadores e Reagentes , Biópsia Líquida , Espectrometria de Massas
11.
Front Immunol ; 13: 958200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072583

RESUMO

Chagas disease, caused by the protozoan Trypanosoma cruzi, is an endemic parasitic disease of Latin America, affecting 7 million people. Although most patients are asymptomatic, 30% develop complications, including the often-fatal Chronic Chagasic Cardiomyopathy (CCC). Although previous studies have demonstrated some genetic deregulations associated with CCCs, the causes of their deregulations remain poorly described. Based on bulk RNA-seq and whole genome DNA methylation data, we investigated the genetic and epigenetic deregulations present in the moderate and severe stages of CCC. Analysis of heart tissue gene expression profile allowed us to identify 1407 differentially expressed transcripts (DEGs) specific from CCC patients. A tissue DNA methylation analysis done on the same tissue has permitted the identification of 92 regulatory Differentially Methylated Regions (DMR) localized in the promoter of DEGs. An in-depth study of the transcription factors binding sites (TFBS) in the DMRs corroborated the importance of TFBS's DNA methylation for gene expression in CCC myocardium. TBX21, RUNX3 and EBF1 are the transcription factors whose binding motif appears to be affected by DNA methylation in the largest number of genes. By combining both transcriptomic and methylomic analysis on heart tissue, and methylomic analysis on blood, 4 biological processes affected by severe CCC have been identified, including immune response, ion transport, cardiac muscle processes and nervous system. An additional study on blood methylation of moderate CCC samples put forward the importance of ion transport and nervous system in the development of the disease.


Assuntos
Cardiomiopatia Chagásica , Doença de Chagas , Trypanosoma cruzi , Doença de Chagas/genética , Epigênese Genética , Humanos , Fatores de Transcrição/genética
12.
Front Immunol ; 12: 755782, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867990

RESUMO

Chagas disease cardiomyopathy (CCC) is an inflammatory dilated cardiomyopathy occurring in 30% of the 6 million infected with the protozoan Trypanosoma cruzi in Latin America. Survival is significantly lower in CCC than ischemic (IC) and idiopathic dilated cardiomyopathy (DCM). Previous studies disclosed a selective decrease in mitochondrial ATP synthase alpha expression and creatine kinase activity in CCC myocardium as compared to IDC and IC, as well as decreased in vivo myocardial ATP production. Aiming to identify additional constraints in energy metabolism specific to CCC, we performed a proteomic study in myocardial tissue samples from CCC, IC and DCM obtained at transplantation, in comparison with control myocardial tissue samples from organ donors. Left ventricle free wall myocardial samples were subject to two-dimensional electrophoresis with fluorescent labeling (2D-DIGE) and protein identification by mass spectrometry. We found altered expression of proteins related to mitochondrial energy metabolism, cardiac remodeling, and oxidative stress in the 3 patient groups. Pathways analysis of proteins differentially expressed in CCC disclosed mitochondrial dysfunction, fatty acid metabolism and transmembrane potential of mitochondria. CCC patients' myocardium displayed reduced expression of 22 mitochondrial proteins belonging to energy metabolism pathways, as compared to 17 in DCM and 3 in IC. Significantly, 6 beta-oxidation enzymes were reduced in CCC, while only 2 of them were down-regulated in DCM and 1 in IC. We also observed that the cytokine IFN-gamma, previously described with increased levels in CCC, reduces mitochondrial membrane potential in cardiomyocytes. Results suggest a major reduction of mitochondrial energy metabolism and mitochondrial dysfunction in CCC myocardium which may be in part linked to IFN-gamma. This may partially explain the worse prognosis of CCC as compared to DCM or IC.


Assuntos
Cardiomiopatia Chagásica/metabolismo , Cardiomiopatia Chagásica/fisiopatologia , Coração/fisiopatologia , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Adolescente , Adulto , Metabolismo Energético/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/patologia , Miocárdio/patologia , Adulto Jovem
13.
Front Immunol ; 12: 755862, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867992

RESUMO

Infection by the protozoan Trypanosoma cruzi causes Chagas disease cardiomyopathy (CCC) and can lead to arrhythmia, heart failure and death. Chagas disease affects 8 million people worldwide, and chronic production of the cytokines IFN-γ and TNF-α by T cells together with mitochondrial dysfunction are important players for the poor prognosis of the disease. Mitochondria occupy 40% of the cardiomyocytes volume and produce 95% of cellular ATP that sustain the life-long cycles of heart contraction. As IFN-γ and TNF-α have been described to affect mitochondrial function, we hypothesized that IFN-γ and TNF-α are involved in the myocardial mitochondrial dysfunction observed in CCC patients. In this study, we quantified markers of mitochondrial dysfunction and nitro-oxidative stress in CCC heart tissue and in IFN-γ/TNF-α-stimulated AC-16 human cardiomyocytes. We found that CCC myocardium displayed increased levels of nitro-oxidative stress and reduced mitochondrial DNA as compared with myocardial tissue from patients with dilated cardiomyopathy (DCM). IFN-γ/TNF-α treatment of AC-16 cardiomyocytes induced increased nitro-oxidative stress and decreased the mitochondrial membrane potential (ΔΨm). We found that the STAT1/NF-κB/NOS2 axis is involved in the IFN-γ/TNF-α-induced decrease of ΔΨm in AC-16 cardiomyocytes. Furthermore, treatment with mitochondria-sparing agonists of AMPK, NRF2 and SIRT1 rescues ΔΨm in IFN-γ/TNF-α-stimulated cells. Proteomic and gene expression analyses revealed that IFN-γ/TNF-α-treated cells corroborate mitochondrial dysfunction, transmembrane potential of mitochondria, altered fatty acid metabolism and cardiac necrosis/cell death. Functional assays conducted on Seahorse respirometer showed that cytokine-stimulated cells display decreased glycolytic and mitochondrial ATP production, dependency of fatty acid oxidation as well as increased proton leak and non-mitochondrial oxygen consumption. Together, our results suggest that IFN-γ and TNF-α cause direct damage to cardiomyocytes' mitochondria by promoting oxidative and nitrosative stress and impairing energy production pathways. We hypothesize that treatment with agonists of AMPK, NRF2 and SIRT1 might be an approach to ameliorate the progression of Chagas disease cardiomyopathy.


Assuntos
Cardiomiopatia Chagásica/metabolismo , Interferon gama/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Idoso , Cardiomiopatia Chagásica/patologia , Cardiomiopatia Chagásica/fisiopatologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/patologia , Miócitos Cardíacos/patologia , Adulto Jovem
14.
Bioanalysis ; 13(5): 295-361, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33511867

RESUMO

The 14th edition of the Workshop on Recent Issues in Bioanalysis (14th WRIB) was held virtually on June 15-29, 2020 with an attendance of over 1000 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations, and regulatory agencies worldwide. The 14th WRIB included three Main Workshops, seven Specialized Workshops that together spanned 11 days in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy and vaccine. Moreover, a comprehensive vaccine assays track; an enhanced cytometry track and updated Industry/Regulators consensus on BMV of biotherapeutics by LCMS were special features in 2020. As in previous years, this year's WRIB continued to gather a wide diversity of international industry opinion leaders and regulatory authority experts working on both small and large molecules to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance and achieving scientific excellence on bioanalytical issues. This 2020 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the Global Bioanalytical Community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2020 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication covers the recommendations on (Part 2A) BAV, PK LBA, Flow Cytometry Validation and Cytometry Innovation and (Part 2B) Regulatory Input. Part 1 (Innovation in Small Molecules, Hybrid LBA/LCMS & Regulated Bioanalysis), Part 3 (Vaccine, Gene/Cell Therapy, NAb Harmonization and Immunogenicity) are published in volume 13 of Bioanalysis, issues 4, and 6 (2021), respectively.


Assuntos
Bioensaio , Biotecnologia , Terapia Baseada em Transplante de Células e Tecidos , Terapia Genética , Relatório de Pesquisa , Biomarcadores/análise , Humanos
15.
An Acad Bras Cienc ; 82(2): 333-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20563414

RESUMO

Egg production in the copepod Acartia tonsa was evaluated using different densities of the microalgae Thalassiosira weissflogii, Chaetoceros muelleri and Isochrysis galbana. Male and female were kept under controlled conditions (salinity 30, 20 degrees C, photoperiod 12L:12D), acclimated to the experimental conditions and left over a period of 24 h to allow copulation. Algal densities tested were equivalent in biovolume and corresponded to 0, 2.5, 5, 10, 20, 40 and 60.10(3) cells.mL-1 of T weissflogii. Ten acclimated female were separated, transferred to glass bottles and exposed for further 24 h to the corresponding experimental medium. After this period, the eggs were fixed and counted. Copepod egg production reached a threshold value when T weissflogii, C. muelleri and I. galbana were supplied at 10.10(3), 140.10(3) and 640.10(3) cells.mL-1, respectively. Mean egg production corresponded to 28.0 +/- 0.5, 20.1 +/- 1.0 and 22.0 +/- 3.5 eggs.female-1 .day-1, respectively. Copepods fed T weissflogii showed the highest mean egg production while those fed I. galbana reached a maximum egg production when the algae were supplied at a density two- to fourfold higher, considering the biovolume of T weissflogii and C. muelleri. These differences are explained considering the different sizes of the microalgae used to feed the copepods.


Assuntos
Ração Animal/provisão & distribuição , Copépodes/fisiologia , Eucariotos , Oviposição/fisiologia , Animais , Feminino , Masculino
16.
PLoS Negl Trop Dis ; 14(12): e0008889, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33351798

RESUMO

Chronic Chagas disease cardiomyopathy (CCC), an especially aggressive inflammatory dilated cardiomyopathy caused by lifelong infection with the protozoan Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Although chronic myocarditis may play a major pathogenetic role, little is known about the molecular mechanisms responsible for its severity. The aim of this study is to study the genes and microRNAs expression in tissues and their connections in regards to the pathobiological processes. To do so, we integrated for the first time global microRNA and mRNA expression profiling from myocardial tissue of CCC patients employing pathways and network analyses. We observed an enrichment in biological processes and pathways associated with the immune response and metabolism. IFNγ, TNF and NFkB were the top upstream regulators. The intersections between differentially expressed microRNAs and differentially expressed target mRNAs showed an enrichment in biological processes such as Inflammation, inflammation, Th1/IFN-γ-inducible genes, fibrosis, hypertrophy, and mitochondrial/oxidative stress/antioxidant response. MicroRNAs also played a role in the regulation of gene expression involved in the key cardiomyopathy-related processes fibrosis, hypertrophy, myocarditis and arrhythmia. Significantly, a discrete number of differentially expressed microRNAs targeted a high number of differentially expressed mRNAs (>20) in multiple processes. Our results suggest that miRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue. This may have a bearing on pathogenesis, biomarkers and therapy.


Assuntos
Cardiomiopatia Chagásica/metabolismo , Cardiomiopatia Chagásica/patologia , Regulação da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Doença Crônica , Genoma Humano , Humanos , MicroRNAs/genética , Análise de Componente Principal
17.
J Immunother Cancer ; 8(2)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33097612

RESUMO

BACKGROUND: This phase Ib study evaluated the safety, clinical activity, pharmacokinetics, and pharmacodynamics (PD) of emactuzumab (anti-colony stimulating factor 1 receptor monoclonal antibody (mAb)) in combination with selicrelumab (agonistic cluster of differentiation 40 mAb) in patients with advanced solid tumors. METHODS: Both emactuzumab and selicrelumab were administered intravenously every 3 weeks and doses were concomitantly escalated (emactuzumab: 500 to 1000 mg flat; selicrelumab: 2 to 16 mg flat). Dose escalation was conducted using the product of independent beta probabilities dose-escalation design. PD analyzes were performed on peripheral blood samples and tumor/skin biopsies at baseline and on treatment. Clinical activity was evaluated using investigator-based and Response Evaluation Criteria In Solid Tumors V.1.1-based tumor assessments. RESULTS: Three dose-limiting toxicities (all infusion-related reactions (IRRs)) were observed at 8, 12 and 16 mg of selicrelumab together with 1000 mg of emactuzumab. The maximum tolerated dose was not reached at the predefined top doses of emactuzumab (1000 mg) and selicrelumab (16 mg). The most common adverse events were IRRs (75.7%), fatigue (54.1%), facial edema (37.8%), and increase in aspartate aminotransferase and creatinine phosphokinase (35.1% both). PD analyzes demonstrated an increase of Ki67+-activated CD8+ T cells accompanied by a decrease of B cells and the reduction of CD14Dim CD16bright monocytes in peripheral blood. The best objective clinical response was stable disease in 40.5% of patients. CONCLUSION: Emactuzumab in combination with selicrelumab demonstrated a manageable safety profile and evidence of PD activity but did not translate into objective clinical responses. TRIALREGISTRATION NUMBER: NCT02760797.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígenos CD40/metabolismo , Neoplasias/tratamento farmacológico , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Anticorpos Monoclonais Humanizados/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Feminino , Humanos , Masculino , Neoplasias/imunologia , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo
18.
Mem Inst Oswaldo Cruz ; 104 Suppl 1: 252-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19753481

RESUMO

The pathogenesis of Chagas disease cardiomyopathy (CCC) is not well understood. Since studies show that myocarditis is more frequent during the advanced stages of the disease, and the prognosis of CCC is worse than that of other dilated cardiomyopathies of non-inflammatory aetiology, which suggest that the inflammatory infiltrate plays a major role in myocardial damage. In the last decade, increasing evidence has shown that inflammatory cytokines and chemokines play a role in the generation of the inflammatory infiltrate and tissue damage. CCC patients have an increased peripheral production of the inflammatory Th1 cytokines IFN-gamma and TNF-alpha when compared to patients with the asymptomatic/indeterminate form. Moreover, Th1-T cells are the main producers of IFN-gamma and TNF-alpha and are frequently found in CCC myocardial inflammatory infiltrate. Over the past several years, our group has collected evidence that shows several cytokines and chemokines produced in the CCC myocardium may also have a non-immunological pathogenic effect via modulation of gene and protein expression in cardiomyocytes and other myocardial cell types. Furthermore, genetic polymorphisms of cytokine, chemokine and innate immune response genes have been associated with disease progression. We will review the molecular and immunological mechanisms of myocardial damage in human CCC in light of recent findings.


Assuntos
Cardiomiopatia Chagásica/imunologia , Quimiocinas/imunologia , Citocinas/imunologia , Doença Aguda , Quimiocinas/genética , Doença Crônica , Citocinas/genética , Progressão da Doença , Humanos , Interferon gama/genética , Interferon gama/imunologia , Polimorfismo Genético , Células Th1/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
19.
Rev Esc Enferm USP ; 53: e03437, 2019 Jun 03.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31166456

RESUMO

OBJECTIVE: To evaluate the levels of engagement of multi-professional health residents of a higher education institution in the northwest of São Paulo. METHOD: A cross-sectional census study in which the Utrecht Work Engagement Scale was used to identify the level of relationship with work (Total score) through 17 questions distributed in the Vigor, Dedication and Absorption dimensions. RESULTS: Participation of 50 professionals, of which 92.0% were female, median age of 24 years, 88.0% were single; 82.0% were satisfied with the program, and 56.0% had thought of giving up. Professionals satisfied with the program had high levels for Total Score (4.0) and Dedication (4.5), and average levels for Absorption (3.9) and Vigor (3.8). Those who reported dissatisfaction had average levels in all dimensions (Vigor: 3.2, Absorption: 3.5, Dedication: 3.5) and in the Total score (3.2), which are considered positive results. CONCLUSION: Professionals presented good levels of engagement in spite of dissatisfactions with the program. The results showed a good relationship between professionals and preceptors and supervisors, which reinforces that support and recognition of professional performance are important for strengthening the engagement, especially at the beginning of the career.


Assuntos
Pessoal de Saúde/psicologia , Internato não Médico , Satisfação Pessoal , Preceptoria , Adulto , Brasil , Estudos Transversais , Feminino , Pessoal de Saúde/educação , Humanos , Relações Interprofissionais , Masculino , Adulto Jovem
20.
Front Immunol ; 8: 806, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769925

RESUMO

Major histocompatibility complex class II (MHCII)-restricted antigen priming of CD4+ T cells is both involved in adaptive immune responses and the pathogenesis of autoimmune diseases. Degradation of invariant chain Ii, a protein that prevents premature peptide loading, is a prerequisite for nascent MHCII-peptide complex formation. A key proteolytic step in this process is mediated by cathepsin S. Inhibition of this cysteine protease is known to result in the intracellular accumulation of Lip10 in B cells. Here, we describe the development and application of a neoepitope-based flow cytometry assay measuring accumulation of Lip10. This novel method enabled the investigation of cathepsin S-dependent MHCII maturation in professional antigen-presenting cell (APC) subsets. Inhibition of cathepsin S by a specific inhibitor, RO5459072, in human PBMC ex vivo resulted in accumulation of Lip10 in B cells and myeloid dendritic cells, but not in plasmacytoid dendritic cells and only to a minor degree in monocytes. We qualified Lip10 as a pharmacodynamic biomarker by showing the cathepsin S inhibitor-dependent accumulation of Lip10 in vivo in cynomolgus monkeys treated with RO5459072. Finally, dosing of RO5459072 in a first-in-human clinical study (www.ClinicalTrials.gov, identifier NCT02295332) exhibited a dose-dependent increase in Lip10, confirming target engagement and demonstrating desired pharmacologic inhibition in vivo. The degree of cathepsin S antagonist-induced maximum Lip10 accumulation in APCs varied significantly between individuals both in vitro and in vivo. This finding has not been reported previously using alternative, less sensitive methods and demands further investigation as to the potential of this biomarker to predict response to treatment. These results will help guide subsequent clinical studies investigating the pharmacokinetic and pharmacodynamic relationship of cathepsin S inhibitor RO5459072 after multiple dosing.

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