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1.
Medicina (Kaunas) ; 56(10)2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33028028

RESUMO

The clinical spectrum of novel coronavirus infection appears to be wide, encompassing asymptomatic infection, mild upper respiratory tract illness, and severe viral pneumonia, with respiratory failure and even death. Autoantibodies, especially antiphospholipid antibodies, can occur in severe infections. Other autoantibodies are seldom reported. Here, a 60-year-old female patient without dry-mouth symptoms detected positive for anti-60 kDa SSA/Ro antibodies on day 43 after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To investigate this unique clinical case of SARS-CoV-2 infection, immunological characteristics of this case were detected by using flow cytometry and were compared to the other three groups of patients-health subjects, 2019 novel coronavirus disease (COVID-19) recovery patients, and Sjögren's syndrome (SS) patients. Monitoring the autoantibody level and the development of subsequently related autoimmune diseases are warranted after SARS-CoV-2 infection.


Assuntos
Anticorpos Antinucleares/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Imunofenotipagem , Pneumonia Viral/imunologia , Feminino , Citometria de Fluxo , Humanos , Pessoa de Meia-Idade , Pandemias , Síndrome de Sjogren
2.
Water Sci Technol ; 82(6): 1062-1069, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33055396

RESUMO

High rate algal ponds (HRAPs) are shallow, mixed systems for wastewater treatment, which use sunlight exposure for disinfection. Little is known regarding the relationships between the bacteria and viruses within HRAP systems. Uniquely, flow cytometry permits the rapid identification of bacterial and viral populations in wastewater samples, separating populations based on genome and particle size. Treated wastewater samples were collected from an HRAP at Kingston on Murray, South Australia. Flow cytometry analysis detected bacterial populations and discriminated virus-like particles (VLP) and large VLP (LVLP). Rapid, short term, fluctuations in the abundance of all three populations were observed. Changes in the abundance of these populations was compared; wastewater composition was used as metadata for the comparisons. Linear regression determined relationships in abundances between bacteria and LVLP (R2 0.2985); LVLP and VLP (R2 0.5829) and bacteria and VLP (R2 0.5778) all with p-values of <0.001. Bacterial, LVLP and VLP abundance positively correlated with each other, indicating potential microbial interactions. Overall, the results suggest a parasitic relationship was occurring and driving the abundances of bacteria and viruses within the system.


Assuntos
Tanques , Eliminação de Resíduos Líquidos , Citometria de Fluxo , Austrália do Sul , Águas Residuárias
3.
Nat Commun ; 11(1): 4482, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901011

RESUMO

Intracellular trafficking governs receptor signaling, pathogenesis, immune responses and fate of nanomedicines. These processes are typically tracked by observing colocalization of fluorescent markers using confocal microscopy. However, this method is low throughput, limited by the resolution of microscopy, and can miss fleeting interactions. To address this, we developed a localization sensor composed of a quenched SNAP-tag substrate (SNAPSwitch) that can be conjugated to biomolecules using click chemistry. SNAPSwitch enables quantitative detection of trafficking to locations of interest within live cells using flow cytometry. Using SNAPSwitch, we followed the trafficking of DNA complexes from endosomes into the cytosol and nucleus. We show that antibodies against the transferrin or hyaluronan receptor are initially sorted into different compartments following endocytosis. In addition, we can resolve which side of the cellular membrane material was located. These results demonstrate SNAPSwitch is a high-throughput and broadly applicable tool to quantitatively track localization of materials in cells.


Assuntos
DNA/metabolismo , Sondas Moleculares/química , Nanopartículas/metabolismo , Proteínas/metabolismo , Animais , Transporte Biológico Ativo , Técnicas Biossensoriais/métodos , Química Click , Citometria de Fluxo , Corantes Fluorescentes , Células HEK293 , Humanos , Camundongos , Microscopia Confocal , Técnicas de Sonda Molecular , Sondas Moleculares/metabolismo , Células NIH 3T3
4.
Anticancer Res ; 40(10): 5379-5391, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988857

RESUMO

BACKGROUND/AIM: Hypoxia-inducible factor 1 (HIF1) inhibitors have been proposed as therapeutic agents for several tumor types. HIF1α is induced by hypoxia and by pathogens in normoxia through toll-like receptors (TLRs). The TLR3 activator polyinosinic:polycytidylic acid [poly(I:C)] induces apoptosis in various types of cancer but not in the most aggressive breast cancer cell lines. We hypothesized that the failure of TLR3 stimulation to induce apoptosis in these cells might be due to an elevated HIF1α level and this link might be exploited. MATERIALS AND METHODS: Poly(I:C)-induced signaling pathway and expression of HIF1α and HIF1α targets were studied in MDA MB-231 and MCF-7 breast cancer cell lines by western blot. Flow cytometry was used for apoptotic responses and vasculogenic mimicry as bioassay. RESULTS: Poly(I:C) increased expression of HIF1α and its targets BCL2 apoptosis regulator and c-MYC. Moreover, using pharmacological or genetic HIF1 inhibition, reduction of poly(I:C)-induced expression of HIF1α was paralleled by lowering of c-MYC and increased sensitivity to poly(I:C)-induced apoptosis, demonstrating the crucial role of this factor. We provide the first evidence in breast cancer cells that TLR3 stimulation induces HIF1α-dependent vasculogenic mimicry. By using specific inhibitors, we identified a signaling cascade upstream of HIF1α induction. CONCLUSION: Combined treatment with poly(I:C) and HIF1 inhibitors deserves consideration as an effective strategy in breast cancer therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Poli I-C/farmacologia , Receptor 3 Toll-Like/genética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais/efeitos dos fármacos , Receptor 3 Toll-Like/agonistas
5.
Anticancer Res ; 40(10): 5437-5443, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988865

RESUMO

BACKGROUND: Neuropilin-1 (NRP1) is a receptor for vascular endothelial growth factor A (VEGFA), and has been reported to be overexpressed in several malignancies. Since angiogenesis plays an important role in pathogenesis of multiple myeloma (MM) and the role of NRP1 in MM has not been studied yet, we characterized the expression of NRP1 in this disease. MATERIALS AND METHODS: The expression level of NRP1 was measured in 140 patients newly diagnosed with MM and 28 healthy controls by flow cytometry and quantitative reverse transcriptase polymerase chain reaction. RESULTS: Expression of NRP1 was significantly reduced on plasma cells (median=2.05%) compared to that on B-cells (median=10.05%, p<0.0001) in bone marrow of patients with MM. In MM, the expression of NRP1 was high on plasmacytoid dendritic cells (median=85.85%) and low on regulatory T-cells (median=0.6%). CONCLUSION: In MM, NRP1 is regulated differentially as compared to other B-cell malignancies at both the RNA and protein level.


Assuntos
Mieloma Múltiplo/genética , Neovascularização Patológica/genética , Neuropilina-1/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Linfócitos B/metabolismo , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Mieloma Múltiplo/patologia , Neovascularização Patológica/sangue , Neovascularização Patológica/patologia , Neuropilina-1/sangue , Transdução de Sinais/genética
6.
Life Sci ; 259: 118391, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32891610

RESUMO

AIMS: Dyslipidemia-associated diabetic retinopathy is featured by macular edema and retinal angiogenesis. This study investigated the in vitro lipotoxicity of free fatty acids and their modulatory roles in regulation of autophagy and angiogenic factor production in cultured human retinal pigment epithelium (RPE) ARPE-19 cells. MAIN METHODS: ARPE-19 cells were exposed to monounsaturated oleic acid (OA), saturated palmitic acid (PA), or both. Cell viability, cell cycle distribution, migration, and autophagy of the treated cells were monitored. Angiogenic factor production was determined by RT-qPCR and ELISA. KEY FINDINGS: OA, but not PA, at doses higher than 500 µM significantly induced cytostasis and lipotoxicity in ARPE-19 cells. OA exposure not only markedly enhanced autophagy flux, but also enhanced cell migration, while PA suppressed motility of RPE cells. Meanwhile, OA stimulated de novo synthesis of angiogenic factors including VEGF and bFGF in ARPE-19 cells. Mechanistically, OA treatment stimulated not only AMPK/mTOR/p70S6K signaling, but also induced hyperphosphorylation of MAPK pathway mediators, including ERK, JNK and p38 MAPK, as well as NF-κB activation. Kinase inhibition assays showed that blockade of PI3K/Akt, MAPK and NF-κB pathways prevented the OA-upregulated VEGF transcription and its peptide release. Comparatively, only NF-κB inhibition significantly suppressed bFGF peptide release from ARPE-19 cells. SIGNIFICANCE: Out findings support the OA-exhibited cytostasis, autophagy modulation and angiogenic factor production in RPE cells. This study sheds light on the interrelationship between metabolic disorder and retinopathy and provides molecular strategies for preventing and treating choroidal neovascularization in diabetic retinopathy.


Assuntos
Indutores da Angiogênese/metabolismo , Autofagia , Ácido Oleico/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Western Blotting , Movimento Celular , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Sistema de Sinalização das MAP Quinases , Ácido Palmítico/metabolismo , Epitélio Pigmentado da Retina/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
7.
Life Sci ; 259: 118390, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32896556

RESUMO

AIMS: This study aimed to evaluate the function and pathway of ATP-binding cassette transporter member A1 (ABCA1)-induced anti-inflammatory response in cells at the feto-maternal interface. MAIN METHODS: The primary amniotic mesenchymal cells (AMCs), chorion cells and decidual cells were isolated from placental membranes of women with uncomplicated pregnancies at full-term (not in labor) using enzymatic digestion. Flow cytometry was used to measure the purity of isolated cells. Immunofluorescence assay was performed to detect the location of ABCA1 and toll-like receptor 4 (TLR4). Reverse transcription PCR and western blotting analyses were used to examine ABCA1, TLR4 and inflammatory factor expression in primary cells. ELISA was used to detect cytokine secretions from the primary cells. KEY FINDINGS: ABCA1 and TLR4 were mainly located in the cell nucleus and cytoplasm of feto-maternal interface cells. ABCA1 expression remained the highest in chorion cells, medium in decidual cells, and weakest in AMCs. Upregulated expression of ABCA1 decreased expression of TLR4 and the levels of pro-inflammatory factors, but increased cytoprotective factors in all cell types. In contrast, downregulated expression of ABCA1 increased the expression of TLR4 and pro-inflammatory factors, but decreased the levels of cytoprotective factors. Downregulated ABCA1 expression followed by decreased TLR4 expression using a small interference RNA (siRNA) induced reduction of interleukin (IL)-1ß and tumor necrosis factor-α (TNF-α) in all cell types. SIGNIFICANCE: ABCA1 at feto-maternal interface acts as an anti-inflammatory role by reducing the expression of TLR4 in uncomplicated pregnancies. ABCA1 might be a potential therapeutic target for preventing gestational diseases.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Troca Materno-Fetal , Receptor 4 Toll-Like/metabolismo , Western Blotting , Células Cultivadas , Córion/metabolismo , Decídua/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Microscopia Confocal , Placenta/metabolismo , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Life Sci ; 259: 118380, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32898524

RESUMO

AIMS: Benign prostatic hyperplasia (BPH) is a progressive disease, which severely affects men's health. Here, we sought to analyze the functions and mechanism of action of the tripartite motif protein 52 (TRIM52), a novel prostate basal cell biomarker in BPH. MATERIALS AND METHODS: Immunohistochemistry assay was performed in sectioned human BPH tissues, BPH-1 cells, and prostate RWPE-1 cells, to detect the expressions of TRIM52 and NF-κB. Western blotting and qRT-PCR analyses were conducted to measure the relative protein and mRNA expression levels, respectively. Further, lentiviral transfection was performed in BPH-1 and RWPE-1 cells to study the overexpression and siRNA knockdown of TRIM52. Dual-luciferase reporter assay was applied to evaluate the relationship between NF-κB and TRIM52. Furthermore, CCK-8 assay and flow cytometry were employed to analyze cell proliferation and apoptosis. KEY FINDINGS: TRIM52 and NF-κB levels were elevated in BPH tissues, and TRIM52 expression positively correlated with NF-κB expression. TRIM52 silencing suppressed the growth of BPH-1 cells and decreased the promoter activity of NF-κB. Moreover, the NF-κB inhibitor, pyrrolidine dithiocarbamate (PDTC), suppressed TRIM52-induced proliferation of RWPE-1 cells and inhibited NF-κB promoter activity in oeTRIM52 transfected RWPE-1 cells. Silencing TRIM52 also inhibited TRAF2 ubiquitination in BPH-1 cells. Further, NF-κB promoter activity in siNC transfected cells was enhanced by the recombinant protein TNF-α and inhibited by siTRIM52. SIGNIFICANCE: TRIM52 accelerated the growth of BPH-1 cells by upregulating NF-κB, and TRIM52 could promote TRAF2 ubiquitination. These findings might contribute to the understanding of the biological functions and action mechanisms of TRIM52 in BPH.


Assuntos
NF-kappa B/metabolismo , Hiperplasia Prostática/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Western Blotting , Progressão da Doença , Citometria de Fluxo , Humanos , Masculino , Hiperplasia Prostática/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ubiquitinação
9.
J Appl Oral Sci ; 28: e20200124, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32901694

RESUMO

OBJECTIVES: To evaluate apoptotic levels of peripheral blood mononuclear cells (PBMCs) and apoptotic regulatory proteins (Bax and Bcl-2) in lymphocyte subsets of oral cancer (OC) patients and healthy controls (HC). METHODOLOGY: The percentage of apoptotic cells and lymphocyte counts were measured in the first cohort using PBMCs obtained from 23 OC patients and 6 HC. In the second cohort, (OC, 33; HC, 13), the mean fluorescence intensity (MFI) of Bax and Bcl-2 in CD19+ B, CD4+ T, CD8+ T, and CD16+56+ natural killer (NK) cells was determined via flow cytometry. RESULTS: The percentage of apoptotic cells was higher in the PBMCs of OC patients than in HC patients, particularly in patients with stage IV cancer (p<0.05). However, lymphocyte counts were significantly lower in stage IV patients (p<0.05). NK CD19+ B and CD16+56+ cell counts were significantly lower in OC patients compared with HC patients (p<0.001 and p<0.01, respectively), but CD4+ T cells were interestingly significantly higher in OC patients (p<0.001). While Bax MFI was slightly higher, Bcl-2 MFI was significantly lower for all four lymphocyte subsets in OC samples, particularly in stage IV patients, when compared with HC. Consequently, Bax/Bcl-2 ratios showed an upward trend from HC to OC patients, particularly those in stage IV. We found similar trends in Bax and Bcl-2 MFI for tumor stage, tumor size, and lymph node involvement. CONCLUSIONS: The increased lymphocyte apoptosis in stage IV OC patients may be related to higher Bax levels and lower Bcl-2 levels. The Bax/Bcl-2 ratio in lymphocytes may be useful to determine the prognosis of OC patients, and could be considered a mean for supportive treatment in the future.


Assuntos
Leucócitos Mononucleares , Neoplasias Bucais , Apoptose , Citometria de Fluxo , Humanos , Células Matadoras Naturais , Subpopulações de Linfócitos
10.
PLoS One ; 15(8): e0237748, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866195

RESUMO

Soil microbiota are considered a source of undiscovered bioactive compounds, yet cultivation of most bacteria within a sample remains generally unsuccessful. Two main reasons behind the unculturability of bacteria are the presence of cells in a viable but not culturable state (such as dormant cells) and the failure to provide the necessary growth requirements in vitro (leading to the classification of some bacterial taxa as yet-to-be-cultured). The present work focuses on the development of a single procedure that helps distinguish between both phenomena of unculturability based on viability staining coupled with flow cytometry and fluorescence-activated cell sorting. In the selected soil sample, the success rate of cultured bacteria was doubled by selecting viable and metabolically active bacteria. It was determined that most of the uncultured fraction was not dormant or dead but likely required different growth conditions. It was also determined that the staining process introduced changes in the taxonomic composition of the outgrown bacterial biomass, which should be considered for further developments. This research shows the potential of flow cytometry and fluorescence-activated cell sorting applied to soil samples to improve the success rate of bacterial cultivation by estimating the proportion of dormant and yet-to-be-cultured bacteria and by directly excluding dormant cells from being inoculated into growth media.


Assuntos
Bactérias/crescimento & desenvolvimento , Técnicas Microbiológicas/métodos , Microbiota/fisiologia , Microbiologia do Solo , Bactérias/química , Bactérias/genética , Biomassa , Separação Celular/métodos , Meios de Cultura , DNA Bacteriano/isolamento & purificação , Estudos de Viabilidade , Citometria de Fluxo/métodos , Corantes Fluorescentes/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Coloração e Rotulagem/métodos
11.
PLoS One ; 15(8): e0237155, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866200

RESUMO

BACKGROUND: Stringent complete response (sCR) is used as a deeper response category than complete response (CR) in multiple myeloma (MM) but may be of limited value in the era of minimal residual disease (MRD) testing. METHODS: Here, we used 4-colour multiparametric flow cytometry (MFC) or next-generation sequencing (NGS) of immunoglobulin genes to analyse and compare the prognostic impact of sCR and MRD monitoring. We included 193 treated patients in two institutions achieving CR, for which both bone marrow aspirates and biopsies were available. RESULTS: We found that neither the serum free light chain ratio, clonality by immunohistochemistry (IHC) nor plasma cell bone marrow infiltration identified CR patients at distinct risk. Patients with sCR had slightly longer progression-free survival. Nevertheless, persistent clonal bone marrow disease was detectable using MFC or NGS and was associated with significantly inferior outcomes compared with MRD-negative cases. CONCLUSION: Our results confirm that sCR does not predict a different outcome and indicate that more sensitive techniques are able to identify patients with differing prognoses. We suggest that MRD categories should be implemented over sCR for the future classification of MM responses.


Assuntos
Mieloma Múltiplo/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/patologia , Confiabilidade dos Dados , Feminino , Citometria de Fluxo/métodos , Seguimentos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Cadeias Leves de Imunoglobulina/sangue , Cadeias Leves de Imunoglobulina/genética , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Plasmócitos/imunologia , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos
12.
Mem Inst Oswaldo Cruz ; 115: e200082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935750

RESUMO

Respiratory failure (RF) is the main cause of hospital admission in HIV/AIDS patients. This study assessed comorbidities and laboratory parameters in HIV/AIDS inpatients with RF (N = 58) in relation to those without RF (N = 36). Tuberculosis showed a huge relative risk and platelet counts were slightly higher in HIV/AIDS inpatients with RF. A flow cytometry assay for reactive oxygen species (ROS) showed lower levels in platelets of these patients in relation to the healthy subjects. However, when stimulated with adrenaline, ROS levels increased in platelets and platelet-derived microparticles of HIV/AIDS inpatients, which may increase the risk of RF during HIV and tuberculosis (HIV-TB) coinfection.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Infecções por HIV/sangue , HIV/imunologia , Espécies Reativas de Oxigênio/sangue , Insuficiência Respiratória/complicações , Fármacos Anti-HIV/uso terapêutico , Biomarcadores/sangue , Plaquetas , Citometria de Fluxo , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Insuficiência Respiratória/sangue
13.
Nat Commun ; 11(1): 4851, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978386

RESUMO

Cell factories converting bio-based precursors to chemicals present an attractive avenue to a sustainable economy, yet screening of genetically diverse strain libraries to identify the best-performing whole-cell biocatalysts is a low-throughput endeavor. For this reason, transcriptional biosensors attract attention as they allow the screening of vast libraries when used in combination with fluorescence-activated cell sorting (FACS). However, broad ligand specificity of transcriptional regulators (TRs) often prohibits the development of such ultra-high-throughput screens. Here, we solve the structure of the TR LysG of Corynebacterium glutamicum, which detects all three basic amino acids. Based on this information, we follow a semi-rational engineering approach using a FACS-based screening/counterscreening strategy to generate an L-lysine insensitive LysG-based biosensor. This biosensor can be used to isolate L-histidine-producing strains by FACS, showing that TR engineering towards a more focused ligand spectrum can expand the scope of application of such metabolite sensors.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/química , Proteínas de Bactérias/química , Técnicas Biossensoriais/métodos , Ligantes , Engenharia Metabólica/métodos , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Proteínas de Bactérias/metabolismo , Corynebacterium glutamicum/metabolismo , Cristalografia , Citometria de Fluxo/métodos , Ensaios de Triagem em Larga Escala/métodos , Lisina/metabolismo , Técnicas Analíticas Microfluídicas , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Termodinâmica
14.
Ann Hematol ; 99(11): 2599-2609, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32935190

RESUMO

Methods to estimate bone marrow plasma cells (BMPC) basically include histopathology, cytomorphology, and flow cytometry. The present study compares the outcomes of these methods with special focus on the impact of BMPC-specific characteristics on their recovery by either method. Laboratory reports of diagnostic samples from 238 consecutive patients with suspected or known plasma cell disease were retrospectively analyzed. The median (IQR) proportion of BMPC was 30.0% (15.0-70.0%) by histological review (hBMPC), 7.0% (2.0-16.0%) by smear review (sBMPC), and 3.0% (0.8-10.0%) by flow cytometry (fBMPC). The disparity of results between core biopsy and aspirate smear was enhanced in case of poor quality of the smear, increased BM fiber content, higher grade cell atypia, expression of CD56 (all P < 0.0001), the number of cytogenetic aberrations (P = 0.0002), and abnormalities of the MYC gene (P = 0.0002). Conversely, expression of CD19 and a non-clonal plasma cell phenotype were associated with a lower difference between hBMPC and sBMPC (both P < 0.0001). The disparity between the percentages of sBMPC and fBMPC was associated with the quality of the smear (P = 0.0007) and expression of CD56 (P < 0.0001). Our results suggest that the recovery of BMPC in aspirate specimens not only is a matter of sampling quality but also depends on biological cell properties. Aspiration failure due to malignant type features of BMPC may lead to misclassification of plasma cell disorders and represent a bias for the detection of minimal residual disease after therapy.


Assuntos
Antígenos CD19/biossíntese , Células da Medula Óssea , Antígeno CD56/biossíntese , Mieloma Múltiplo , Proteínas de Neoplasias/biossíntese , Plasmócitos , Adulto , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/classificação , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Neoplasia Residual , Plasmócitos/metabolismo , Plasmócitos/patologia , Estudos Retrospectivos
15.
Ecotoxicol Environ Saf ; 202: 110912, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800247

RESUMO

Occupational exposure to pesticides has been identified as a factor that predisposes to disorders of the immune system. Immunosuppression, autoimmunity, cancer of various organs and other diseases in people who apply these products have been reported by the studies. This study aimed to investigate the relationship between occupational exposure to pesticides and the immunological profile in 43 farmers exposed to mixtures of pesticides for at least 15 years. A control group composed of 30 individuals without a history of occupational exposure to pesticides was also evaluated. Peripheral blood samples were processed by flow cytometry and cells were labelled with an 8-color monoclonal antibody panel. Plasma cytokines were also measured. Significant increase in classical monocytes (p < 0.001) and dendritic cells (p < 0.001) in the exposed group was observed as well in total T cells (p = 0.04), central memory CD8 T cells (p = 0.02) and effector memory CD8 T cells (p = 0.01). On the other hand, the activation markers of T cells as the expression of CD57, HLA-DR, CD25 and CD28 were evaluated and no difference was found between groups. When the B cells were analyzed, a significant decrease in total B cells (p = 0.01), regulatory B cells (p < 0.001) and plasmablasts (p < 0.001) in the exposed group, compared to healthy controls, was observed. Pro-inflammatory IL-6 was significantly elevated (p = 0.04) in the plasma of farmers compared to that of controls. The constant antigenic stimulus that occurs during exposure to pesticides can favor the recruitment of dendritic cells and macrophages (APCs) presents in the skin and respiratory tract. In the secondary lymphoid organs, the CD4 T and B cells that process such antigens are possibly undergoing proliferative exhaustion, with the consequent depletion of all mature B subpopulations. The resulting drop in humoral immunity may be offset by an increase in the number of circulating CD8 T lymphocytes due to their cytotoxic action.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Exposição Ocupacional/estatística & dados numéricos , Praguicidas/toxicidade , Adulto , Poluentes Ocupacionais do Ar/análise , Linfócitos B/imunologia , Brasil , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/metabolismo , Fazendeiros , Feminino , Citometria de Fluxo , Antígenos HLA-DR/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-2 , Masculino , Pessoa de Meia-Idade , Praguicidas/análise , Praguicidas/metabolismo
16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1363-1366, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798427

RESUMO

OBJECTIVE: To explore the appropriate procedures for preparing extracellular microvesicles (MV) derived from human mesenchymal stem cells (MSC). METHODS: Human MSCs from umbilical cords were cultured in a serum-free medium and maintained in a basal medium for 72 hours after the cell confluence reached to 80%. The supernatants of cultured cells were collected and MVs were enriched. MVs were identified by flow cytometry and electron microscopy. The total protein amount in MVs was used as a parameter for the content of MVs. The supernatants were adjusted to different pH values, and the output of MVs was detected. The supernatants were also collected for enriching the MV and detecting the protein content of MV after the cells were maintained in the basic medium for different time. RESULTS: Flow cytometric analysis showed that the MVs expressed CD9, CD63 and CD81, morphologically presented round under an electron microscope and the diameter of MV was around 100 nm. After enrichment of MV, the protein content of MVs in the supernatants was 416.8±128.1, 255.4±77.9 and 142.8±46.4 µg per 107 MSC,respectively at pH of supernatant 3, 7 and 9 (P<0.05). The protein content of the supernatants per 107 MSC was 173.6±44.5, 262.4±49.6 and 364.2±37.8 µg respectively after starvation culture for 48, 72 and 96 hrs (P<0.05). CONCLUSION: MVs can be readily collected after MSCs were starved for 96 hours, and the pH of the supernatants is adjusted at 3.0.


Assuntos
Micropartículas Derivadas de Células , Células-Tronco Mesenquimais , Células Cultivadas , Citometria de Fluxo , Humanos , Cordão Umbilical
17.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1405-1413, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748598

RESUMO

In vitro compartmentalization (IVC) links genotype and phenotype by compartmentalizing individual genes (including expression system) or cells into a micro-droplet reaction region. Combined with fluorescence-activated cell sorting (FACS), it can detect and separate single droplets in ultra-high throughput. IVC-FACS screening method has been widely used in protein engineering, enzyme directed evolution, etc. However, it is difficult to control the homogeneity of droplet size by mechanical dispersion method in previous studies, which seriously affects the quantitative detection of droplets and reduces the efficiency and accuracy of this screening method. With the rapid development of microfluidic chip manufacturing technology, the microfluidic chip-based methods for droplet generation are becoming more efficient and controllable. In this study, firstly, the water-in-oil (W/O) single-layer droplet generation chip was used to prepare single-layer monodisperse W1/O droplets at a high generation frequency, and then the W1/O droplets were reinjected into water-in-oil-in-water (W/O/W) double-layer droplet generation chip to prepare uniform W1/O/W2 double-layer emulsion droplets. By optimizing the flow rate and ratio of the oil and water phases, a single-layer micro-droplet can be generated with a diameter range from 15.4 to 23.2 µm and remain stable for several days under normal incubation. Then the single-layer droplets were reinjected into the double emulsion generation chip. By adjusting the flow rate of drop phase, oil phase and water phase, the double-layer emulsion droplets with a diameter range from 30 to 100 µm at a rate of 1 000 droplets/s could be obtained. Escherichia coli embedded in the double-layer emulsion droplets could be cultured and induced for protein expression. This study lays a foundation for the establishment of a high-throughput screening method based on the droplet and flow cytometry.


Assuntos
Emulsões , Ensaios de Triagem em Larga Escala , Microfluídica , Citometria de Fluxo , Microfluídica/métodos
18.
Virology ; 548: 39-48, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32838945

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 is the agent responsible for the coronavirus disease 2019 (COVID-19) global pandemic. SARS-CoV-2 is closely related to SARS-CoV, which caused the 2003 SARS outbreak. Although numerous reagents were developed to study SARS-CoV infections, few have been applicable to evaluating SARS-CoV-2 infection and immunity. Current limitations in studying SARS-CoV-2 include few validated assays with fully replication-competent wild-type virus. We have developed protocols to propagate, quantify, and work with infectious SARS-CoV-2. Here, we describe: (1) virus stock generation, (2) RT-qPCR quantification of SARS-CoV-2 RNA; (3) detection of SARS-CoV-2 antigen by flow cytometry, (4) quantification of infectious SARS-CoV-2 by focus-forming and plaque assays; and (5) validated protocols for virus inactivation. Collectively, these methods can be adapted to a variety of experimental designs, which should accelerate our understanding of SARS-CoV-2 biology and the development of effective countermeasures against COVID-19.


Assuntos
Betacoronavirus/fisiologia , Cultura de Vírus/métodos , Inativação de Vírus , Animais , Antígenos Virais/análise , Betacoronavirus/genética , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/imunologia , Linhagem Celular , Chlorocebus aethiops , Contenção de Riscos Biológicos , Meios de Cultura , Citometria de Fluxo , RNA Viral/análise , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Vero , Ensaio de Placa Viral , Replicação Viral
19.
Nat Commun ; 11(1): 4056, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792483

RESUMO

Autophagy has been associated with oncogenesis with one of its emerging key functions being its contribution to the metabolism of tumors. Therefore, deciphering the mechanisms of how autophagy supports tumor cell metabolism is essential. Here, we demonstrate that the inhibition of autophagy induces an accumulation of lipid droplets (LD) due to a decrease in fatty acid ß-oxidation, that leads to a reduction of oxidative phosphorylation (OxPHOS) in acute myeloid leukemia (AML), but not in normal cells. Thus, the autophagic process participates in lipid catabolism that supports OxPHOS in AML cells. Interestingly, the inhibition of OxPHOS leads to LD accumulation with the concomitant inhibition of autophagy. Mechanistically, we show that the disruption of mitochondria-endoplasmic reticulum (ER) contact sites (MERCs) phenocopies OxPHOS inhibition. Altogether, our data establish that mitochondria, through the regulation of MERCs, controls autophagy that, in turn finely tunes lipid degradation to fuel OxPHOS supporting proliferation and growth in leukemia.


Assuntos
Autofagia/fisiologia , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia/metabolismo , Mitocôndrias/metabolismo , Animais , Autofagia/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Citometria de Fluxo , Humanos , Leucemia/genética , Leucemia Mieloide Aguda/patologia , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Lipogênese/genética , Lipogênese/fisiologia , Camundongos , Mitocôndrias/genética , Oxirredução , Fosforilação Oxidativa
20.
Nat Commun ; 11(1): 4071, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792491

RESUMO

Arrest of oligodendrocyte (OL) differentiation and remyelination following myelin damage in multiple sclerosis (MS) is associated with neurodegeneration and clinical worsening. We show that Glutathione S-transferase 4α (Gsta4) is highly expressed during adult OL differentiation and that Gsta4 loss impairs differentiation into myelinating OLs in vitro. In addition, we identify Gsta4 as a target of both dimethyl fumarate, an existing MS therapy, and clemastine fumarate, a candidate remyelinating agent in MS. Overexpression of Gsta4 reduces expression of Fas and activity of the mitochondria-associated Casp8-Bid-axis in adult oligodendrocyte precursor cells, leading to improved OL survival during differentiation. The Gsta4 effect on apoptosis during adult OL differentiation was corroborated in vivo in both lysolecithin-induced demyelination and experimental autoimmune encephalomyelitis models, where Casp8 activity was reduced in Gsta4-overexpressing OLs. Our results identify Gsta4 as an intrinsic regulator of OL differentiation, survival and remyelination, as well as a potential target for future reparative MS therapies.


Assuntos
Glutationa Transferase/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Caspase 8/genética , Caspase 8/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Glutationa Transferase/genética , Homeostase/genética , Homeostase/fisiologia , Imuno-Histoquímica , Masculino , Microglia/citologia , Microglia/metabolismo , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Fagocitose/genética , Fagocitose/fisiologia , Processamento de Proteína Pós-Traducional , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Remielinização/genética , Remielinização/fisiologia
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