Publications by authors named "Ashare A"

Background: Adult people with cystic fibrosis (PwCF) have a higher risk of end-stage kidney disease than the general population. The nature and mechanism of kidney disease in CF are unknown. This study quantifies urinary kidney injury markers and examines the hypothesis that neutrophil activation and lung infection are associated with early kidney injury in CF.

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Background: Adult people with cystic fibrosis (PwCF) have a higher risk of end-stage kidney disease than the general population. The nature and mechanism of kidney disease in CF are unknown. This study quantifies urinary kidney injury markers and examines the hypothesis that neutrophil activation and lung infection are associated with early kidney injury in CF.

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Although tobramycin increases lung function in people with cystic fibrosis (pwCF), the density of () in the lungs is only modestly reduced by tobramycin; hence, the mechanism whereby tobramycin improves lung function is not completely understood. Here, we demonstrate that tobramycin increases 5' tRNA-fMet halves in outer membrane vesicles (OMVs) secreted by laboratory and CF clinical isolates of . The 5' tRNA-fMet halves are transferred from OMVs into primary CF human bronchial epithelial cells (CF-HBEC), decreasing OMV-induced IL-8 and IP-10 secretion.

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Unlabelled: Although tobramycin increases lung function in people with cystic fibrosis (pwCF), the density of in the lungs is only modestly reduced by tobramycin; hence, the mechanism whereby tobramycin improves lung function is not completely understood. Here, we demonstrate that tobramycin increases 5' tRNA-fMet halves in outer membrane vesicles (OMVs) secreted by laboratory and CF clinical isolates of . The 5' tRNA-fMet halves are transferred from OMVs into primary CF human bronchial epithelial cells (CF-HBEC), decreasing OMV-induced IL-8 and IP-10 secretion.

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Article Synopsis
  • Recent research has advanced our understanding of SARS-CoV-2 and antibody responses, but the detailed composition of circulating antibodies remains largely unexplored.
  • A study using Ig-Seq analyzed the antibody profiles specific to SARS-CoV-2's spike protein and its receptor binding domain in four subjects over six months after infection, revealing that about 50% of RBD-specific IgG did not recognize the spike protein in its stabilized form.
  • The study also evaluated monoclonal antibodies from infected individuals, finding that while some neutralized the virus, others showed limited binding to different variants, highlighting the complexities of the immune response to SARS-CoV-2.
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Macrophage dysfunction has been well-described in Cystic Fibrosis (CF) and may contribute to bacterial persistence in the lung. Whether CF macrophage dysfunction is related directly to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) in macrophages or an indirect consequence of chronic inflammation and mucostasis is a subject of ongoing debate. CFTR modulators that restore CFTR function in epithelial cells improve global CF monocyte inflammatory responses but their direct effects on macrophages are less well understood.

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  • Cystic fibrosis (CF) patients often suffer from chronic lung infections caused by bacteria and fungi, leading to research on how these organisms evolve in response to their environment.
  • Whole-genome sequencing revealed that individuals with CF developed mutations in the gene related to the mitochondrial iron transporter Mrs4, which resulted in a loss of function.
  • The mutations allowed fungi to enhance their iron acquisition mechanisms, suggesting that these adaptations help them thrive in the iron-restricted conditions of CF lung infections, potentially guiding future therapeutic strategies.
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The genetic disease cystic fibrosis (CF) frequently leads to chronic lung infections by bacteria and fungi. We identified three individuals with CF with persistent lung infections dominated by ( ) . Whole genome sequencing analysis of multiple isolates from each infection found evidence for selection for mutants in the gene in all three distinct lung-associated populations.

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Background: While acute respiratory distress following electronic cigarette (e-cig) use has been described, the effects of chronic e-cig use on lung health are currently unknown. Acute e-cigarette/vaping product use-associated lung injury (EVALI) has been highlighted recently in numerous cases across the United States. Numerous EVALI case reports highlight alterations in alveolar macrophages, justifying investigation of this key immune sentinel of the lung in habitual e-cig users.

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Alveolar macrophages (AMs) reside on the luminal surface of the airways and alveoli, ensuring proper gas exchange by ingesting cellular debris and pathogens, and regulating inflammatory responses. Therefore, understanding the heterogeneity and diverse roles played by AMs, interstitial macrophages, and recruited monocytes is critical for treating airway diseases. We performed single-cell RNA sequencing on 113,213 bronchoalveolar lavage cells from four healthy and three uninflamed cystic fibrosis subjects and identified two MARCKSLGMNIMs, FOLR2SELENOP and SPP1PLA2G7 IMs, monocyte subtypes, DC1, DC2, migDCs, plasmacytoid DCs, lymphocytes, epithelial cells, and four AM superclusters (families) based on the gene expression of and These four AM families have at least eight distinct functional members (subclusters) named after their differentially expressed gene(s): IGF1, CCL18, CXCL5, cholesterol, chemokine, metallothionein, interferon, and small-cluster AMs.

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Article Synopsis
  • Microbes evolve in predictable ways, with specific metabolic regulation driving the presence of loss-of-function mutations in a bacterial pathogen, rather than inter-strain interactions.
  • * The LasR protein, linked to quorum sensing and virulence, has been found that its absence can lead to more severe disease, and this is influenced by the behavior of the CbrAB system in metabolic substrate usage.
  • * Analysis of lung infection samples in cystic fibrosis revealed that certain metabolites can enhance the growth of LasR mutants and correlate with worsening lung function, suggesting that metabolism in the body contributes to pathogen evolution and disease severity.
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A recent workshop titled "Developing Models to Study Polymicrobial Infections," sponsored by the Dartmouth Cystic Fibrosis Center (DartCF), explored the development of new models to study the polymicrobial infections associated with the airways of persons with cystic fibrosis (CF). The workshop gathered 35+ investigators over two virtual sessions. Here, we present the findings of this workshop, summarize some of the challenges involved with developing such models, and suggest three frameworks to tackle this complex problem.

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The prevalence of Aspergillus fumigatus colonization in individuals with cystic fibrosis (CF) and subsequent fungal persistence in the lung is increasingly recognized. However, there is no consensus for clinical management of A. fumigatus in CF individuals, due largely to uncertainty surrounding A.

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Background: Despite increased interest in mesenchymal stromal cell (MSC)-based cell therapies for acute respiratory distress syndrome (ARDS), clinical investigations have not yet been successful and our understanding of the potential mechanisms of MSC actions in ARDS remains limited. ARDS is driven by an acute severe innate immune dysregulation, often characterised by inflammation, coagulation and cell injury. How this inflammatory microenvironment influences MSC functions remains to be determined.

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The evolution of pathogens in response to selective pressures present during chronic infections can influence their persistence and virulence and the outcomes of antimicrobial therapy. Because subpopulations within an infection can be spatially separated and the host environment can fluctuate, an appreciation of the pathways under selection may be most easily revealed through the analysis of numerous isolates from single infections. Here, we continued our analysis of a set of clonally derived () isolates from a single chronic lung infection with a striking enrichment in the number of alleles of Genetic and genomic analyses found evidence for repeated acquisition of gain-of-function mutations that conferred constitutive Mrr1 activity.

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Data on adverse events from research bronchoscopy with bronchoalveolar lavage (BAL) in patients with cystic fibrosis (CF) is lacking. As research bronchoscopy with BAL is useful for isolation of immune cells and investigation of CF lung microbiome, we sought to investigate the safety of bronchoscopy in adult patients with CF. Between November 2016 and September 2019, we performed research bronchoscopies on CF subjects (32) and control subjects (82).

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Mutations in alter macrophage responses, for example, by reducing their ability to phagocytose and kill bacteria. Altered macrophage responses may facilitate bacterial infection and inflammation in the lungs, contributing to morbidity and mortality in cystic fibrosis (CF). Extracellular vesicles (EVs) are secreted by multiple cell types in the lungs and participate in the host immune response to bacterial infection, but the effect of EVs secreted by CF airway epithelial cells (AEC) on CF macrophages is unknown.

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Various pathogens use differing strategies to evade host immune response including modulating the host's epigenome. Here, we investigate if EVs secreted from alter DNA methylation in human lung macrophages, thereby potentially contributing to a dysfunctional innate immune response. Using a genome-wide DNA methylation approach, we demonstrate that EVs alter certain host cell DNA methylation patterns.

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Growing evidence demonstrates that human mesenchymal stromal cells (MSCs) modify their in vivo anti-inflammatory actions depending on the specific inflammatory environment encountered. Understanding this better is crucial to refine MSC-based cell therapies for lung and other diseases. Using acute exacerbations of cystic fibrosis (CF) lung disease as a model, the effects of ex vivo MSC exposure to clinical bronchoalveolar lavage fluid (BALF) samples, as a surrogate for the in vivo clinical lung environment, on MSC viability, gene expression, secreted cytokines, and mitochondrial function were compared with effects of BALF collected from healthy volunteers.

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, a Gram-negative bacterium, is one of the most common pathogens colonizing the lungs of cystic fibrosis patients. secrete extracellular vesicles (EVs) that contain LPS and other virulence factors that modulate the host's innate immune response, leading to an increased local proinflammatory response and reduced pathogen clearance, resulting in chronic infection and ultimately poor patient outcomes. Lung macrophages are the first line of defense in the airway innate immune response to pathogens.

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Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene. Although viral respiratory tract infections are, in general, more severe in patients with CF compared with the general population, a small number of studies indicate that SARS-CoV-2 does not cause a worse infection in CF. This is surprising since comorbidities including preexisting lung disease have been reported to be associated with worse outcomes in SARS-CoV-2 infections.

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Cystic fibrosis (CF) is a genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in chronic bacterial lung infections and tissue damage. CF macrophages exhibit reduced bacterial killing and increased inflammatory signaling. Iron is elevated in the CF lung and is a critical nutrient for bacteria, including the common CF pathogen Pseudomonas aeruginosa (Pa).

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Background: Chronic infection and concomitant airway inflammation is the leading cause of morbidity and mortality for people living with cystic fibrosis (CF). Although chronic infection in CF is undeniably polymicrobial, involving a lung microbiota, infection surveillance and control approaches remain underpinned by classical aerobic culture-based microbiology. How to use microbiomics to direct clinical management of CF airway infections remains a crucial challenge.

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Article Synopsis
  • Several pulmonary diseases, like cystic fibrosis and smoking-related COPD, show a pattern of being more prevalent in the upper lobes of the lungs, which differ physiologically and metabolically from the lower lobes.
  • The study investigated whether regional differences in the lung could lead to DNA methylation changes in lung macrophages, which may affect their response to environmental challenges.
  • Using advanced DNA methylation techniques, the researchers found 95 specific CpG loci with significant methylation differences, linking these changes to inflammatory processes and metabolic variations in lung macrophages.
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Cigarette smoke inhalation exposes the respiratory system to thousands of potentially toxic substances and causes chronic obstructive pulmonary disease (COPD). COPD is characterized by cycles of inflammation and infection with a dysregulated immune response contributing to disease progression. While smoking cessation can slow the damage in COPD, lung immunity remains impaired.

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