Alpha-1 antitrypsin mitigates the inhibition of airway epithelial cell repair by neutrophil elastase

Copyright © 2016 by the American Thoracic Society. Neutrophil elastase (NE) activity is associated with many destructive lung diseases and is a predictor for structural lung damage in early cystic fibrosis (CF), which suggests normal maintenance of airway epitheliumis prevented byuninhibitedNE.However, limited data exist on how the NE activity in airways of very young children with CF affects function of the epithelia. The aimof this studywas to determine if NE activity could inhibit epithelial homeostasis and repair and whether any functional effect was reversible by antiprotease alpha-1 antitrypsin (a1AT) treatment. Viability, inflammation, apoptosis, and proliferation were assessed in healthy non-CF and CF pediatric primary airway epithelial cells (pAEC non-CF and pAEC CF , respectively) during exposure to physiologically relevant NE. The effect of NE activity on pAEC CF wound repair was also assessed.We report that viability after 48 hours was significantly decreased by 100 nM NE in pAEC non-CF and pAEC CF owing to rapid cellular detachment that was accompanied by inflammatory cytokine release. Furthermore, both phenotypes initiated an apoptotic response to 100 nM NE, whereas ≥50 nM NE activity significantly inhibited the proliferative capacity of cultures. Similar concentrations of NE also significantly inhibited wound repair of pAEC CF , but this effect was reversed by the addition of a1AT. Collectively, our results demonstrate free NE activity is deleterious for epithelial homeostasis and support the hypothesis that proteases inthe airway contribute directly toCF structural lung disease. Our results also highlight the need to investigate antiprotease therapies in early CF disease in more detail

The effect of Y and Ti on FeCrAl oxidation at 1400 °C

Inco alloy MA956 (Fe-20wt%Cr-4.5%Al-0.35%Ti + 3vol% Y2O3-Al2O3) was oxidized in 1 atm of dry, flowing O2 at 1400 °C . Good scale-metal adhesion was observed. Some spalling occurred upon cooling, but it remained within the oxide, not through to the bare metal. Cyclic experiments showed good scale adherence. Y was found to segregate to the oxide grain boundaries and by implication to have modified oxidation behavior through a reactive element effect. However, while at lower temperatures Ti was also found to segregate, at 1400 °C very little segregation was detected. Instead, ≈ 0.5µm TiNx particles were observed in the scale. These particles appear to have cracked the surrounding oxide during cooldown. It is postulated that the spallation observed was due to these particles. MA956 was compared to Kanthal alloy APM (Fe-20%Cr-5.5%Al-0.03%Ti + ≈2vol%ZrO2-Al2O3) and a conventionally-cast Fe-20%Cr-10%Al alloy, in order to study the effect of Y and Ti

Interleukin-1 is associated with inflammation and structural lung disease in young children with cystic fibrosis

© 2018 European Cystic Fibrosis Society Background: Little is known about the role of interleukin (IL)-1 in the pathogenesis of cystic fibrosis (CF) lung disease. This study investigated the relationship between IL-1 signalling, neutrophilic inflammation and structural lung changes in children with CF. Methods: Bronchoalveolar lavage fluid (BALf) from 102 children with CF were used to determine IL-1α, IL-1β, IL-8 levels and neutrophil elastase (NE) activity, which were then correlated to structural lung changes observed on chest computed tomography (CT) scans. Results: IL-1α and IL-1β were detectable in BAL in absence of infection, increased in the presence of bacterial infection and correlated with IL-8 (p < 0.0001), neutrophils (p < 0.0001) and NE activity (p < 0.01 and p < 0.001). IL-1α had the strongest association with structural lung disease (p < 0.01) in the absence of infection (uninfected: p < 0.01 vs. infected: p = 0.122). Conclusion: Our data associates IL-1α with early structural lung damage in CF and suggests this pathway as a novel anti-inflammatory target

Nontuberculous Mycobacterial Aggregation is Regulated by C:N Balance

The current treatment regimen for nontuberculous mycobacteria (NTM) involves long courses of antibiotic cocktails that demonstrate limited efficacy and cause frequent and serious side effects. Mycobacterium abscessus, in particular, is difficult to treat, motivating studies to identify new therapeutic targets. Experiments using zebrafish and human cell culture lines have demonstrated that M. abscessus is more virulent when aggregated into cord-like biofilms, at least in part because of the decreased ability of phagocytes to efficiently engulf and kill corded M. abscessus cells

Matrix metalloproteinase activation by free neutrophil elastase contributes to bronchiectasis progression in early cystic fibrosis

© ERS 2015. Neutrophil elastase is the most significant predictor of bronchiectasis in early-life cystic fibrosis; however, the causal link between neutrophil elastase and airway damage is not well understood. Matrix metalloproteinases (MMPs) play a crucial role in extracellular matrix modelling and are activated by neutrophil elastase. The aim of this study was to assess if MMP activation positively correlates with neutrophil elastase activity, disease severity and bronchiectasis in young children with cystic fibrosis. Total MMP-1, MMP-2, MMP-7, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-1 levels were measured in bronchoalveolar lavage fluid collected from young children with cystic fibrosis during annual clinical assessment. Active/pro-enzyme ratio of MMP-9 was determined by gelatin zymography. Annual chest computed tomography imaging was scored for bronchiectasis. A higher MMP-9/TIMP-1 ratio was associated with free neutrophil elastase activity. In contrast, MMP-2/TIMP-2 ratio decreased and MMP-1 and MMP-7 were not detected in the majority of samples. Ratio of active/pro-enzyme MMP-9 was also higher in the presence of free neutrophil elastase activity, but not infection. Across the study cohort, both MMP-9/TIMP-1 and active MMP-9 were associated with progression of bronchiectasis. Both MMP-9/TIMP-1 and active MMP-9 increased with free neutrophil elastase and were associated with bronchiectasis, further demonstrating that free neutrophil elastase activity should be considered an important precursor to cystic fibrosis structural disease

Using integrated omics to assess the effects of rhinovirus infection in children with Cystic Fibrosis (CF)

Introduction/Aim: Children with Cystic Fibrosis (CF) typically exhibit prolonged and severe symptoms during rhinovirus (RV) infection compared to healthy children. Here, we studied the host-rhinovirus interaction signature after infection, integrating two omics: (1) Whole transcriptome sequencing (WTS) to determine the viral load and host’s gene expression, and (2) metabolomics to profile the metabolites associated with the viral infection of primary tracheal epithelial cells obtained from healthy children (H) and those with CF. Methods: WTS and hydrophilic interaction liquid chromatography (HILIC) coupled to mass spectrometry, were used to identify the differences in transcripts/metabolites and RV coverage produced by H (3.9 ± 1.5 years; n=8) and CF (2.6 ± 1.8 years; n=8; all p.Phe508del/p.Phe508del) primary epithelial cells at 24 hours post-infection with human rhinovirus 1B. Univariate and multivariate analyses were then performed to identify the infection hallmark. Results: RV coverage in uninfected cells (Mock) was less than 0.5X, whereas, infected cells presented 44.4X and 101.6X of RV in children with and without CF respectively. Global RV infection was associated with 14 metabolites and 1713 genes differential expressed. From these, several metabolic pathways were found dysregulated including inositol metabolism and glycerophospholipid biosynthesis. Conclusion: Metabolic host-derived pathways associated with RV infection were identified. Although functional analysis is still required, these pathways could be used as potential biomarkers of RV infection in CF. Future analysis will help to understand whether these compounds can be targeted for antiviral purposes