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1.
Cell ; 183(4): 1070-1085.e12, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33031744

RESUMO

The SARS-CoV-2 pandemic has caused extreme human suffering and economic harm. We generated and characterized a new mouse-adapted SARS-CoV-2 virus that captures multiple aspects of severe COVID-19 disease in standard laboratory mice. This SARS-CoV-2 model exhibits the spectrum of morbidity and mortality of COVID-19 disease as well as aspects of host genetics, age, cellular tropisms, elevated Th1 cytokines, and loss of surfactant expression and pulmonary function linked to pathological features of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). This model can rapidly access existing mouse resources to elucidate the role of host genetics, underlying molecular mechanisms governing SARS-CoV-2 pathogenesis, and the protective or pathogenic immune responses related to disease severity. The model promises to provide a robust platform for studies of ALI and ARDS to evaluate vaccine and antiviral drug performance, including in the most vulnerable populations (i.e., the aged) using standard laboratory mice.


Assuntos
Lesão Pulmonar Aguda/patologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Animais , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , COVID-19 , Linhagem Celular , Quimiocinas/sangue , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Citocinas/sangue , Modelos Animais de Doenças , Feminino , Humanos , Pulmão/patologia , Pulmão/fisiologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Síndrome do Desconforto Respiratório/patologia , SARS-CoV-2 , Índice de Gravidade de Doença , Taxa de Sobrevida
2.
Cell ; 181(4): 848-864.e18, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32298651

RESUMO

Chronic obstructive pulmonary disease (COPD) is a progressive condition of chronic bronchitis, small airway obstruction, and emphysema that represents a leading cause of death worldwide. While inflammation, fibrosis, mucus hypersecretion, and metaplastic epithelial lesions are hallmarks of this disease, their origins and dependent relationships remain unclear. Here we apply single-cell cloning technologies to lung tissue of patients with and without COPD. Unlike control lungs, which were dominated by normal distal airway progenitor cells, COPD lungs were inundated by three variant progenitors epigenetically committed to distinct metaplastic lesions. When transplanted to immunodeficient mice, these variant clones induced pathology akin to the mucous and squamous metaplasia, neutrophilic inflammation, and fibrosis seen in COPD. Remarkably, similar variants pre-exist as minor constituents of control and fetal lung and conceivably act in normal processes of immune surveillance. However, these same variants likely catalyze the pathologic and progressive features of COPD when expanded to high numbers.


Assuntos
Pulmão/patologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Adulto , Idoso , Animais , Feminino , Fibrose/fisiopatologia , Humanos , Inflamação/patologia , Pulmão/metabolismo , Masculino , Metaplasia/fisiopatologia , Camundongos , Pessoa de Meia-Idade , Neutrófilos/imunologia , Pneumonia/patologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Análise de Célula Única/métodos , Células-Tronco/metabolismo
3.
Cell ; 182(2): 429-446.e14, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32526206

RESUMO

The mode of acquisition and causes for the variable clinical spectrum of coronavirus disease 2019 (COVID-19) remain unknown. We utilized a reverse genetics system to generate a GFP reporter virus to explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogenesis and a luciferase reporter virus to demonstrate sera collected from SARS and COVID-19 patients exhibited limited cross-CoV neutralization. High-sensitivity RNA in situ mapping revealed the highest angiotensin-converting enzyme 2 (ACE2) expression in the nose with decreasing expression throughout the lower respiratory tract, paralleled by a striking gradient of SARS-CoV-2 infection in proximal (high) versus distal (low) pulmonary epithelial cultures. COVID-19 autopsied lung studies identified focal disease and, congruent with culture data, SARS-CoV-2-infected ciliated and type 2 pneumocyte cells in airway and alveolar regions, respectively. These findings highlight the nasal susceptibility to SARS-CoV-2 with likely subsequent aspiration-mediated virus seeding to the lung in SARS-CoV-2 pathogenesis. These reagents provide a foundation for investigations into virus-host interactions in protective immunity, host susceptibility, and virus pathogenesis.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Sistema Respiratório/virologia , Genética Reversa/métodos , Idoso , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , COVID-19 , Linhagem Celular , Células Cultivadas , Chlorocebus aethiops , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Fibrose Cística/patologia , DNA Recombinante , Feminino , Furina/metabolismo , Humanos , Imunização Passiva , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Mucosa Nasal/patologia , Mucosa Nasal/virologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/imunologia , Sistema Respiratório/patologia , SARS-CoV-2 , Serina Endopeptidases/metabolismo , Células Vero , Virulência , Replicação Viral , Soroterapia para COVID-19
4.
Nature ; 604(7904): 111-119, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35355018

RESUMO

Mapping the spatial distribution and molecular identity of constituent cells is essential for understanding tissue dynamics in health and disease. We lack a comprehensive map of human distal airways, including the terminal and respiratory bronchioles (TRBs), which are implicated in respiratory diseases1-4. Here, using spatial transcriptomics and single-cell profiling of microdissected distal airways, we identify molecularly distinct TRB cell types that have not-to our knowledge-been previously characterized. These include airway-associated LGR5+ fibroblasts and TRB-specific alveolar type-0 (AT0) cells and TRB secretory cells (TRB-SCs). Connectome maps and organoid-based co-cultures reveal that LGR5+ fibroblasts form a signalling hub in the airway niche. AT0 cells and TRB-SCs are conserved in primates and emerge dynamically during human lung development. Using a non-human primate model of lung injury, together with human organoids and tissue specimens, we show that alveolar type-2 cells in regenerating lungs transiently acquire an AT0 state from which they can differentiate into either alveolar type-1 cells or TRB-SCs. This differentiation programme is distinct from that identified in the mouse lung5-7. Our study also reveals mechanisms that drive the differentiation of the bipotent AT0 cell state into normal or pathological states. In sum, our findings revise human lung cell maps and lineage trajectories, and implicate an epithelial transitional state in primate lung regeneration and disease.


Assuntos
Linhagem da Célula , Pulmão , Células-Tronco , Células Epiteliais Alveolares , Animais , Diferenciação Celular , Conectoma , Fibroblastos , Perfilação da Expressão Gênica , Humanos , Pulmão/citologia , Pneumopatias , Camundongos , Organoides , Primatas , Regeneração , Análise de Célula Única , Células-Tronco/citologia
5.
Am J Respir Crit Care Med ; 209(4): 374-389, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38016030

RESUMO

Rationale: Non-cystic fibrosis bronchiectasis (NCFB) may originate in bronchiolar regions of the lung. Accordingly, there is a need to characterize the morphology and molecular characteristics of NCFB bronchioles. Objectives: Test the hypothesis that NCFB exhibits a major component of bronchiolar disease manifest by mucus plugging and ectasia. Methods: Morphologic criteria and region-specific epithelial gene expression, measured histologically and by RNA in situ hybridization and immunohistochemistry, identified proximal and distal bronchioles in excised NCFB lungs. RNA in situ hybridization and immunohistochemistry assessed bronchiolar mucus accumulation and mucin gene expression. CRISPR-Cas9-mediated IL-1R1 knockout in human bronchial epithelial cultures tested IL-1α and IL-1ß contributions to mucin production. Spatial transcriptional profiling characterized NCFB distal bronchiolar gene expression. Measurements and Main Results: Bronchiolar perimeters and lumen areas per section area were increased in proximal, but not distal, bronchioles in NCFB versus control lungs, suggesting proximal bronchiolectasis. In NCFB, mucus plugging was observed in ectatic proximal bronchioles and associated nonectatic distal bronchioles in sections with disease. MUC5AC and MUC5B mucins were upregulated in NCFB proximal bronchioles, whereas MUC5B was selectively upregulated in distal bronchioles. Bronchiolar mucus plugs were populated by IL-1ß-expressing macrophages. NCFB sterile sputum supernatants induced human bronchial epithelial MUC5B and MUC5AC expression that was >80% blocked by IL-1R1 ablation. Spatial transcriptional profiling identified upregulation of genes associated with secretory cells, hypoxia, interleukin pathways, and IL-1ß-producing macrophages in mucus plugs and downregulation of epithelial ciliogenesis genes. Conclusions: NCFB exhibits distinctive proximal and distal bronchiolar disease. Both bronchiolar regions exhibit bronchiolar secretory cell features and mucus plugging but differ in mucin gene regulation and ectasia.


Assuntos
Bronquiectasia , Fibrose Cística , Humanos , Bronquíolos , Dilatação Patológica , Bronquiectasia/genética , Mucinas/metabolismo , Interleucina-1beta , Fibrose , RNA , Mucina-5AC/genética
6.
Am J Physiol Lung Cell Mol Physiol ; 326(3): L292-L302, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38252871

RESUMO

Since its invention in the late 1980s, the air-liquid-interface (ALI) culture system has been the standard in vitro model for studying human airway biology and pulmonary diseases. However, in a conventional ALI system, cells are cultured on a porous plastic membrane that is much stiffer than human airway tissues. Here, we develop a gel-ALI culture system by simply coating the plastic membrane with a thin layer of hydrogel with tunable stiffness matching that of healthy and fibrotic airway tissues. We determine the optimum gel thickness that does not impair the transport of nutrients and biomolecules essential to cell growth. We show that the gel-ALI system allows human bronchial epithelial cells (HBECs) to proliferate and differentiate into pseudostratified epithelium. Furthermore, we discover that HBECs migrate significantly faster on hydrogel substrates with stiffness matching that of fibrotic lung tissues, highlighting the importance of mechanical cues in human airway remodeling. The developed gel-ALI system provides a facile approach to studying the effects of mechanical cues in human airway biology and in modeling pulmonary diseases.NEW & NOTEWORTHY In a conventional ALI system, cells are cultured on a plastic membrane that is much stiffer than human airway tissues. We develop a gel-ALI system by coating the plastic membrane with a thin layer of hydrogel with tunable stiffness matching that of healthy and fibrotic airway tissues. We discover that human bronchial epithelial cells migrate significantly faster on hydrogel substrates with pathological stiffness, highlighting the importance of mechanical cues in human airway remodeling.


Assuntos
Remodelação das Vias Aéreas , Pneumopatias , Humanos , Células Epiteliais , Pulmão , Hidrogéis , Células Cultivadas
7.
Am J Respir Crit Care Med ; 206(11): 1336-1352, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35816430

RESUMO

Rationale: The incidence and sites of mucus accumulation and molecular regulation of mucin gene expression in coronavirus (COVID-19) lung disease have not been reported. Objectives: To characterize the incidence of mucus accumulation and the mechanisms mediating mucin hypersecretion in COVID-19 lung disease. Methods: Airway mucus and mucins were evaluated in COVID-19 autopsy lungs by Alcian blue and periodic acid-Schiff staining, immunohistochemical staining, RNA in situ hybridization, and spatial transcriptional profiling. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected human bronchial epithelial (HBE) cultures were used to investigate mechanisms of SARS-CoV-2-induced mucin expression and synthesis and test candidate countermeasures. Measurements and Main Results: MUC5B and variably MUC5AC RNA concentrations were increased throughout all airway regions of COVID-19 autopsy lungs, notably in the subacute/chronic disease phase after SARS-CoV-2 clearance. In the distal lung, MUC5B-dominated mucus plugging was observed in 90% of subjects with COVID-19 in both morphologically identified bronchioles and microcysts, and MUC5B accumulated in damaged alveolar spaces. SARS-CoV-2-infected HBE cultures exhibited peak titers 3 days after inoculation, whereas induction of MUC5B/MUC5AC peaked 7-14 days after inoculation. SARS-CoV-2 infection of HBE cultures induced expression of epidermal growth factor receptor (EGFR) ligands and inflammatory cytokines (e.g., IL-1α/ß) associated with mucin gene regulation. Inhibiting EGFR/IL-1R pathways or administration of dexamethasone reduced SARS-CoV-2-induced mucin expression. Conclusions: SARS-CoV-2 infection is associated with a high prevalence of distal airspace mucus accumulation and increased MUC5B expression in COVID-19 autopsy lungs. HBE culture studies identified roles for EGFR and IL-1R signaling in mucin gene regulation after SARS-CoV-2 infection. These data suggest that time-sensitive mucolytic agents, specific pathway inhibitors, or corticosteroid administration may be therapeutic for COVID-19 lung disease.


Assuntos
COVID-19 , Humanos , Prevalência , SARS-CoV-2 , Mucina-5B/genética , Mucina-5AC/genética , Muco/metabolismo , Pulmão/metabolismo , Receptores ErbB , RNA/metabolismo
8.
Am J Respir Crit Care Med ; 203(10): 1275-1289, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33321047

RESUMO

Rationale: Identification of the specific cell types expressing CFTR (cystic fibrosis [CF] transmembrane conductance regulator) is required for precision medicine therapies for CF. However, a full characterization of CFTR expression in normal human airway epithelia is missing. Objectives: To identify the cell types that contribute to CFTR expression and function within the proximal-distal axis of the normal human lung. Methods: Single-cell RNA (scRNA) sequencing (scRNA-seq) was performed on freshly isolated human large and small airway epithelial cells. scRNA in situ hybridization (ISH) and single-cell qRT-PCR were performed for validation. In vitro culture systems correlated CFTR function with cell types. Lentiviruses were used for cell type-specific transduction of wild-type CFTR in CF cells. Measurements and Main Results: scRNA-seq identified secretory cells as dominating CFTR expression in normal human large and, particularly, small airway superficial epithelia, followed by basal cells. Ionocytes expressed the highest CFTR levels but were rare, whereas the expression in ciliated cells was infrequent and low. scRNA ISH and single-cell qRT-PCR confirmed the scRNA-seq findings. CF lungs exhibited distributions of CFTR and ionocytes similar to those of normal control subjects. CFTR mediated Cl- secretion in cultures tracked secretory cell, but not ionocyte, densities. Furthermore, the nucleotide-purinergic regulatory system that controls CFTR-mediated hydration was associated with secretory cells and not with ionocytes. Lentiviral transduction of wild-type CFTR produced CFTR-mediated Cl- secretion in CF airway secretory cells but not in ciliated cells. Conclusions: Secretory cells dominate CFTR expression and function in human airway superficial epithelia. CFTR therapies may need to restore CFTR function to multiple cell types, with a focus on secretory cells.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/metabolismo , Fibrose Cística/patologia , Células Epiteliais/metabolismo , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Estudos de Casos e Controles , Técnicas de Cultura de Células , Humanos
9.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142171

RESUMO

Mucociliary clearance is a critical defense mechanism for the lungs governed by regionally coordinated epithelial cellular activities, including mucin secretion, cilia beating, and transepithelial ion transport. Cystic fibrosis (CF), an autosomal genetic disorder caused by the dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) channel, is characterized by failed mucociliary clearance due to abnormal mucus biophysical properties. In recent years, with the development of highly effective modulator therapies, the quality of life of a significant number of people living with CF has greatly improved; however, further understanding the cellular biology relevant to CFTR and airway mucus biochemical interactions are necessary to develop novel therapies aimed at restoring CFTR gene expression in the lungs. In this article, we discuss recent advances of transcriptome analysis at single-cell levels that revealed a heretofore unanticipated close relationship between secretory MUC5AC and MUC5B mucins and CFTR in the lungs. In addition, we review recent findings on airway mucus biochemical and biophysical properties, focusing on how mucin secretion and CFTR-mediated ion transport are integrated to maintain airway mucus homeostasis in health and how CFTR dysfunction and restoration of function affect mucus properties.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Depuração Mucociliar , Muco/metabolismo , Qualidade de Vida
10.
Am J Respir Cell Mol Biol ; 63(6): 831-842, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32946266

RESUMO

Fibroblasts provide a structural framework for multiple organs and are essential for wound repair and fibrotic processes. Here, we demonstrate functional roles of FOXL1 (forkhead box L1), a transcription factor that characterizes the pulmonary origin of lung fibroblasts. We detected high FOXL1 transcripts associated with DNA hypomethylation and super-enhancer formation in lung fibroblasts, which is in contrast with fibroblasts derived from other organs. RNA in situ hybridization and immunohistochemistry in normal lung tissue indicated that FOXL1 mRNA and protein are expressed in submucosal interstitial cells together with airway epithelial cells. Transcriptome analysis revealed that FOXL1 could control a broad array of genes that potentiate fibroblast function, including TAZ (transcriptional coactivator with PDZ-binding motif)/YAP (Yes-associated protein) signature genes and PDGFRα (platelet-derived growth factor receptor-α). FOXL1 silencing in lung fibroblasts attenuated cell growth and collagen gel contraction capacity, underscoring the functional importance of FOXL1 in fibroproliferative reactions. Of clinical importance, increased FOXL1 mRNA expression was found in fibroblasts of idiopathic pulmonary fibrosis lung tissue. Our observations suggest that FOXL1 regulates multiple functional aspects of lung fibroblasts as a key transcription factor and is involved in idiopathic pulmonary fibrosis pathogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fibroblastos/metabolismo , Fibrose/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Proliferação de Células/fisiologia , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Pulmão/patologia
12.
Am J Respir Crit Care Med ; 199(6): 715-727, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30352166

RESUMO

RATIONALE: MUC5AC and MUC5B are the predominant gel-forming mucins in the mucus layer of human airways. Each mucin has distinct functions and site-specific expression. However, the regional distribution of expression and cell types that secrete each mucin in normal/healthy human airways are not fully understood. OBJECTIVES: To characterize the regional distribution of MUC5B and MUC5AC in normal/healthy human airways and assess which cell types produce these mucins, referenced to the club cell secretory protein (CCSP). METHODS: Multiple airway regions from 16 nonsmoker lungs without a history of lung disease were studied. MUC5AC, MUC5B, and CCSP expression/colocalization were assessed by RNA in situ hybridization and immunohistochemistry in five lungs with histologically healthy airways. Droplet digital PCR and cell cultures were performed for absolute quantification of MUC5AC/5B ratios and protein secretion, respectively. MEASUREMENTS AND MAIN RESULTS: Submucosal glands expressed MUC5B, but not MUC5AC. However, MUC5B was also extensively expressed in superficial epithelia throughout the airways except for the terminal bronchioles. Morphometric calculations revealed that the distal airway superficial epithelium was the predominant site for MUC5B expression, whereas MUC5AC expression was concentrated in proximal, cartilaginous airways. RNA in situ hybridization revealed MUC5AC and MUC5B were colocalized with CCSP-positive secretory cells in proximal superficial epithelia, whereas MUC5B and CCSP-copositive cells dominated distal regions. CONCLUSIONS: In normal/healthy human airways, MUC5B is the dominant secretory mucin in the superficial epithelium and glands, with distal airways being a major site of expression. MUC5B and MUC5AC expression is a property of CCSP-positive secretory cells in superficial airway epithelia.


Assuntos
Pulmão/diagnóstico por imagem , Pulmão/fisiologia , Mucina-5AC/análise , Mucina-5B/análise , Transporte Proteico/fisiologia , Fenômenos Fisiológicos Respiratórios , Humanos
13.
Am J Respir Crit Care Med ; 200(2): 220-234, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30973754

RESUMO

Rationale: The goal was to connect elements of idiopathic pulmonary fibrosis (IPF) pathogenesis, including chronic endoplasmic reticulum stress in respiratory epithelia associated with injury/inflammation and remodeling, distal airway mucus obstruction and honeycomb cyst formation with accumulation of MUC5B (mucin 5B), and associations between IPF risk and polymorphisms in the MUC5B promoter. Objectives: To test whether the endoplasmic reticulum (ER) stress sensor protein ERN2 (ER-to-nucleus signaling 2) and its downstream effector, the spliced form of XBP1S (X-box-binding protein 1), regulate MUC5B expression and differentially activate the MUC5B promoter variant in respiratory epithelia. Methods: Primary human airway epithelial (HAE) cells, transgenic mouse models, human IPF lung tissues, and cell lines expressing XBP1S and MUC5B promoters were used to explore relationships between the ERN2/XBP1S pathway and MUC5B. An inhibitor of the pathway, KIRA6, and XBP1 CRISPR-Cas9 were used in HAE cells to explore therapeutic potential. Measurements and Main Results: ERN2 regulated MUC5B and MUC5AC mRNAs. Downstream XBP1S selectively promoted MUC5B expression in vitro and in distal murine airway epithelia in vivo. XBP1S bound to the proximal region of the MUC5B promoter and differentially upregulated MUC5B expression in the context of the MUC5B promoter rs35705950 variant. High levels of ERN2 and XBP1S were associated with excessive MUC5B mRNAs in distal airways of human IPF lungs. Cytokine-induced MUC5B expression in HAE cells was inhibited by KIRA6 and XBP1 CRISPR-Cas9. Conclusions: A positive feedback bistable ERN2-XBP1S pathway regulates MUC5B-dominated mucus obstruction in IPF, providing an unfolded protein response-dependent mechanism linking the MUC5B promoter rs35705950 polymorphism with IPF pathogenesis. Inhibiting ERN2-dependent pathways/elements may provide a therapeutic option for IPF.


Assuntos
Endorribonucleases/genética , Fibrose Pulmonar Idiopática/genética , Proteínas de Membrana/genética , Proteínas Serina-Treonina Quinases/genética , Mucosa Respiratória/metabolismo , Proteína 1 de Ligação a X-Box/genética , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/metabolismo , Regulação da Expressão Gênica , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Polimorfismo Genético , Cultura Primária de Células , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo
14.
Antimicrob Agents Chemother ; 63(12)2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31570396

RESUMO

Staphylococcus aureus is responsible for numerous community outbreaks and is one of the most frequent causes of nosocomial infections with significant morbidity and mortality. While the function of lytic transglycosylases (LTs) in relation to cell division, biofilm formation, and antibiotic resistance has been determined for several bacteria, their role in S. aureus remains largely unknown. The only known LTs in S. aureus are immunodominant staphylococcal antigen A (IsaA) and Staphylococcus epidermidis D protein (SceD). Our study demonstrates that, in a strain of methicillin-resistant S. aureus (MRSA), IsaA and SceD contribute differently to biofilm formation and ß-lactam resistance. Deletion of isaA, but not sceD, led to decreased biofilm formation. Additionally, in isaA-deleted strains, ß-lactam resistance was significantly decreased compared to that of wild-type strains. Plasmid-based expression of mecA, a major determinant of ß-lactam resistance in MRSA, in an isaA-deleted strain did not restore ß-lactam resistance, demonstrating that the ß-lactam susceptibility phenotype is exhibited by isaA mutant regardless of the production level of PBP2a. Overall, our results suggest that IsaA is a potential therapeutic target for MRSA infections.

15.
Ann Clin Microbiol Antimicrob ; 17(1): 44, 2018 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-30577829

RESUMO

BACKGROUND: Catheter-related infection (CRI) is one of the serious challenges in clinical practice. This preliminary clinical study aimed to examine whether next-generation sequencing (NGS) targeting 16S rDNA, which was PCR-amplified directly from the tip of a central venous catheter (CVC), can be used to identify causative pathogens in CRI, compared to the culture method. METHODS: Hospitalized patients, from whom a CVC had just been removed, were prospectively enrolled and divided into the CRI-suspected and routine removal groups. DNA was extracted from the sonication fluid of CVC specimens derived from patients. For analysis of bacterial composition by NGS, the V3-V4 fragments of bacterial 16S rDNA were PCR-amplified, followed by index PCR and paired-end sequencing on an Illumina MiSeq device. Conventional culture methods were also performed in the CRI-suspected group. RESULTS: Of CVCs collected from the 156 enrolled patients (114 men; mean age 65.6 years), a total of 14 specimens [nine out of 31 patients suspected with CRI and five out of 125 patients without infection symptoms (routine removal group)] were PCR-positive. In five patients with definite CRI, Staphylococcus was the most frequently detected genus by NGS (4/5 specimens), although no pathogens were detected by NGS in the one remaining specimen. The genera identified by NGS were consistent with those from conventional culture tests. There was high agreement between NGS and the culture method in the CRI-suspected group, with sensitivity and specificity values of 80.0% and 76.9%, respectively; meanwhile, the false-positive rate of NGS was as low as 4.0% in the routine removal group. Moreover, several genera, besides the genus identified by culture test, were detected in each patient with definite CRI and surgical site infection (SSI). Additionally, in one patient with SSI, Enterococcaceae were detected not only by NGS but also by abdominal abscess drainage culture. CONCLUSIONS: NGS targeting 16S rDNA was able to analyze the bacterial composition of CVC specimens and detect causative pathogens in patients with CRI and was therefore suggested as a promising diagnostic tool for CRI.


Assuntos
Infecções Relacionadas a Cateter/microbiologia , Cateteres Venosos Centrais/microbiologia , DNA Bacteriano/genética , Adulto , Idoso , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade
16.
Klin Padiatr ; 230(3): 138-141, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29618138

RESUMO

BACKGROUND: Burkitt lymphoma (BL) in children often presents with abdominal localization. Intestinal perforations have been described mainly during treatment. We report on a three-year-old patient with abdominal BL who was diagnosed with a duodenocolonic fistula. CASE REPORT: A three-year-old boy presented with diarrhea, crampy abdominal pain, and a four-week history of loss of appetite and weight. Ultrasound and MRI detected a colonic tumor forming a duodenocolonic fistula which was verified by gastroduodenoscopy. A surgical biopsy revealed BL. The stage III BL with low LDH was treated with four courses of BFM-type short-pulse chemotherapy. After two courses of chemotherapy the patient developed a mechanic ileus. A segmental resection of a short segment of the colon at the right flexure carrying the residual tumor mass with cicatricial stenosis and fistula followed by colonic end to end anastomosis and covering of the fistula by omentum major were carried out without complication. 15 days after surgery, two additional courses of chemotherapy could be administrated and the boy is in ongoing remission and free of any symptoms with a follow-up interval of 18 months. CONCLUSIONS: Duodeonocolonic fistula at presentation in a child with abdominal BL is extremely rare. Delayed surgery after size of the tumor bulk has been reduced by chemotherapy might represent a risk adapted approach. However, due to limited experience with duodenocolonic fistulas even in larger pediatric lymphoma trials any decision has to be based on the problems to be faced in individual cases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/patologia , Colo/diagnóstico por imagem , Diarreia/etiologia , Fístula Intestinal/diagnóstico por imagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biópsia , Linfoma de Burkitt/cirurgia , Pré-Escolar , Duodenoscopia , Gastroscopia , Humanos , Fístula Intestinal/etiologia , Fístula Intestinal/cirurgia , Imageamento por Ressonância Magnética , Masculino , Estadiamento de Neoplasias , Resultado do Tratamento , Ultrassonografia
18.
BMC Pulm Med ; 16(1): 71, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27160723

RESUMO

BACKGROUND: Meigs' syndrome is defined as the presence of a benign ovarian tumor with pleural effusion and ascites that resolve after removal of the tumor. The pathogenesis of the production of ascites and pleural effusion in this syndrome remains unknown. Aside from pleural effusion and ascites, pericardial effusion is rarely observed in Meigs' syndrome. Here, we report the first case of Meigs' syndrome with preceding pericardial effusion in advance of pleural effusion. CASE PRESENTATION: An 84-year-old Japanese non-smoking woman with a history of lung cancer, treated by surgery, was admitted due to gradual worsening of dyspnea that had occurred over the previous month. She had asymptomatic and unchanging pericardial effusion and a pelvic mass, which had been detected 3 and 11 years previously, respectively. The patient was radiologically followed-up without the need for treatment. Two months before admission, the patient underwent a right upper lobectomy for localized lung adenocarcinoma and intraoperative pericardial fenestration confirmed that the pericardial effusion was not malignant. However, she began to experience dyspnea on exertion leading to admission. A chest, abdomen, and pelvis computed tomography scan confirmed the presence of right-sided pleural and pericardial effusion and ascites with a left ovarian mass. Repeated thoracentesis produced cultures that were negative for any microorganism and no malignant cells were detected in the pleural effusions. Pleural fluid accumulation persisted despite a tube thoracostomy for pleural effusion drainage. With a suspicion of Meigs' syndrome, the patient underwent surgical resection of the ovarian mass and histopathological examination of the resected mass showed ovarian fibroma. Pleural and pericardial effusion as well as ascites resolved after tumor resection, confirming a diagnosis of Meigs' syndrome. This clinical course suggests a strong association between pericardial effusion and ovarian fibroma, as well as pleural and peritoneal fluid. CONCLUSIONS: In female patients with unexplained pericardial effusion and an ovarian tumor, clinicians should consider the possibility of Meigs' syndrome. Although a malignant disease should be suspected in all patients with undiagnosed pleural and/or pericardial effusion, Meigs' syndrome is curable by tumor resection and should be differentiated from malignancy.


Assuntos
Síndrome de Meigs/complicações , Derrame Pericárdico/etiologia , Derrame Pleural/etiologia , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Síndrome de Meigs/diagnóstico , Derrame Pericárdico/diagnóstico , Derrame Pleural/diagnóstico , Tomografia Computadorizada por Raios X
19.
J Infect Chemother ; 21(11): 795-801, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26410549

RESUMO

PURPOSE: There have been scarce data evaluating the differences of clinical characteristics and prognosis of chronic pulmonary aspergillosis (CPA) depending on underlying pulmonary diseases. We tried to clarify them in CPA patients who had pulmonary emphysema or previous pulmonary tuberculosis. METHODS: We reviewed and evaluated CPA patients diagnosed between 2007 and 2013 with pulmonary emphysema (PE group; n = 29), with previous pulmonary tuberculosis (PT group; n = 47) and with combination of these 2 underlying conditions (CTE group; n = 24). RESULTS: In CT findings, fungus balls were rare in PE group (7% in PE group and 36% in PT group; p = 0.006). Compared with PT group, PE group patients exhibited more frequent preceding antibiotics administration (45% vs 11%; p = 0.002) and fever (52% vs 17%; p = 0.002), less frequent hemosputum (24% vs 57%; p = 0.008), and more frequent consolidations in imaging (79% vs 38%; p = 0.001) and respiratory failure (34% vs 13%; p = 0.020), possibly suggesting more acute clinical manifestations of CPA in emphysematous patients. Trend of the differences between PT and PE group was not changed when patients with fungal balls were excluded. Multivariate Cox regression analysis of risks for all-cause mortality revealed age (HR, 1.079; p = 0.002) and emphysema (HR, 2.45; p = 0.040) as risk factors. CONCLUSIONS: Assessment of underlying lung diseases is needed when we estimate prognosis and consider treatment of CPA patients. Particularly, emphysematous patients can be presented as refractory pneumonia and show poor prognosis.


Assuntos
Enfisema/complicações , Aspergilose Pulmonar/complicações , Aspergilose Pulmonar/epidemiologia , Tuberculose/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Aspergilose Pulmonar/mortalidade , Aspergilose Pulmonar/fisiopatologia , Estudos Retrospectivos
20.
Microsc Microanal ; 20(2): 469-83, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24564988

RESUMO

High-throughput immuno-electron microscopy is required to capture the protein-protein interactions realizing physiological functions. Atmospheric scanning electron microscopy (ASEM) allows in situ correlative light and electron microscopy of samples in liquid in an open atmospheric environment. Cells are cultured in a few milliliters of medium directly in the ASEM dish, which can be coated and transferred to an incubator as required. Here, cells were imaged by optical or fluorescence microscopy, and at high resolution by gold-labeled immuno-ASEM, sometimes with additional metal staining. Axonal partitioning of neurons was correlated with specific cytoskeletal structures, including microtubules, using primary-culture neurons from wild type Drosophila, and the involvement of ankyrin in the formation of the intra-axonal segmentation boundary was studied using neurons from an ankyrin-deficient mutant. Rubella virus replication producing anti-double-stranded RNA was captured at the host cell's plasma membrane. Fas receptosome formation was associated with clathrin internalization near the surface of primitive endoderm cells. Positively charged Nanogold clearly revealed the cell outlines of primitive endoderm cells, and the cell division of lactic acid bacteria. Based on these experiments, ASEM promises to allow the study of protein interactions in various complexes in a natural environment of aqueous liquid in the near future.


Assuntos
Animais Geneticamente Modificados , Técnicas Citológicas/métodos , Drosophila/citologia , Microscopia Eletrônica de Varredura/métodos , Microscopia Imunoeletrônica/métodos , Animais , Endoderma/citologia , Lactobacillales/citologia , Lactobacillales/fisiologia , Neurônios/citologia , Neurônios/fisiologia , Cultura Primária de Células , Vírus da Rubéola/fisiologia , Coloração e Rotulagem/métodos , Replicação Viral
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