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Cigarette smoke (CS) is the leading risk factor to develop COPD. Therefore, the pathologic effects of whole CS on the differentiation of primary small airway epithelial cells (SAEC) were investigated, using cells from three healthy donors and three COPD patients, cultured under ALI (air-liquid interface) conditions. The analysis of the epithelial physiology demonstrated that CS impaired barrier formation and reduced cilia beat activity. Although, COPD-derived ALI cultures preserved some features known from COPD patients, CS-induced effects were similarly pronounced in ALI cultures from patients compared to healthy controls. RNA sequencing analyses revealed the deregulation of marker genes for basal and secretory cells upon CS exposure. The comparison between gene signatures obtained from the in vitro model (CS vs. air) with a published data set from human epithelial brushes (smoker vs. non-smoker) revealed a high degree of similarity between deregulated genes and pathways induced by CS. Taken together, whole cigarette smoke alters the differentiation of small airway basal cells in vitro. The established model showed a good translatability to the situation in vivo. Thus, the model can help to identify and test novel therapeutic approaches to restore the impaired epithelial repair mechanisms in COPD, which is still a high medical need.

Immobilization of bacteriophages onto solid supports such as magnetic particles has demonstrated ultralow detection limits as biosensors for the separation and detection of their host bacteria. While the potential impact of magnetized phages is high, the current methods of immobilization are either weak, costly, inefficient, or laborious making them less viable for commercialization. In order to bridge this gap, we have developed a highly efficient, site-specific, and low-cost method to immobilize bacteriophages onto solid supports. While streptavidin-biotin represents an ideal conjugation method, the functionalization of magnetic particles with streptavidin requires square meters of coverage and therefore is not amenable to a low-cost assay. Here, we genetically engineered bacteriophages to allow synthesis of a monomeric streptavidin during infection of the bacterial host. The monomeric streptavidin was fused to a capsid protein (Hoc) to allow site-specific self-assembly of up to 155 fusion proteins per capsid. Biotin coated magnetic nanoparticles were functionalized with mSA-Hoc T4 phage demonstrated in an E. coli detection assay with a limit of detection of < 10 CFU in 100 mLs of water. This work highlights the creation of genetically modified bacteriophages with a novel capsid modification, expanding the potential for bacteriophage functionalized biotechnologies., (© 2023. Springer Nature Limited.)

In vivo presentation of airway hyper-responsiveness (AHR) at the different time points of the allergic reaction is not clearly understood. The purpose of this study was to investigate how AHR manifests in the airway and the lung parenchyma in vivo following exposure to different stimuli and in the early and late phases of asthma after allergen exposure. Ovalbumin (OVA)-induced allergic asthma model was established using 6-week female BALB/c mice. Enhanced pause was measured with a non-invasive method to assess AHR. The dynamic changes of the airway and lung parenchyma were evaluated with ultra-high-resolution computed tomography (128 multi-detector, 1024 × 1024 matrix) for 10 h. While the methacholine challenge showed no grossly visible changes in the proximal airway and lung parenchyma despite provoking AHR, the OVA challenge induced significant immediate changes manifesting as peribronchial ground glass opacities, consolidations, air-trapping, and paradoxical proximal airway dilatations. After resolution of immediate response, multiple episodes of AHRs occurred with paradoxical proximal airway dilatation and peripheral air-trapping in late phase over a prolonged time period in vivo. Understanding of airflow limitation based on the structural changes of asthmatic airway would be helpful to make an appropriate drug delivery strategy for the treatment of asthma. [ABSTRACT FROM AUTHOR]

Superoxide dismutase 3 (SOD3), an antioxidant enzyme, is known as extracellular SOD (EC-SOD) because it is the predominant form in extracellular fluids. The diversity of plasma EC-SOD concentration is associated with the SOD3 p.R231G missense variant genotype. To clarify the association among SOD3 genotype, plasma EC-SOD concentration, and comorbidity in Oldest Old, we analyzed genome-wide associations with plasma EC-SOD concentration and associations between EC-SOD concentration and medical history classified by the SOD3 genotype in the Very Old (85–99 years old, n = 505) and Centenarians (over 100 years old, n = 595). The results revealed that SOD3 p.R231G was the most significant variant associated with plasma EC-SOD concentration. Although no significant difference was observed in medical histories between the SOD3 p.R231G variant non-carriers and carriers, higher EC-SOD concentration in plasma of SOD3 p.R231G variant non-carriers was associated with a high odds ratio for chronic kidney disease (OR = 2.70, 95% CI = 1.98–3.72) and low odds ratio for diabetes mellitus (DM) (OR = 0.61, 95% CI = 0.39–0.95). Comparison with 11 plasma biomarkers for age-related disease showed that plasma EC-SOD concentration correlated with adiponectin and estimated glomerular filtration rate with creatinine correction; therefore, we deduced that EC-SOD co-operates with adiponectin and possesses beneficial functions for DM in the Oldest Old. [ABSTRACT FROM AUTHOR]

We investigated the effects of particulate matter (PM) on mortality in patients diagnosed with asthma-COPD overlap (ACO) or 'pure COPD'. Subjects from the National Health Insurance Service-National Sample Cohort of Korea, who were aged 40 years or above and had newly diagnosed COPD since 2009 were selected. Finally, 6,313 patients were enrolled and divided into 'pure COPD' and ACO groups. Average PM 10 exposure data were obtained using Kriging interpolation from 2001 to 2013. Hazard ratios(HR) were estimated using a time-varying Cox regression model. Exposure to PM 10 for 1, 3, and 6 months was associated with an increase in non-accidental mortality in the entire COPD group, especially the ACO group. When a stratified analysis of 3-month exposure was performed by sex, the highest HR was found in women with ACO (HR = 1.153; 95% confidence intervals [CI]: 1.121, 1.185). A stratified analysis according to smoking status showed that ACO patients had the highest HR among never smokers (HR = 1.151; 95% CI; 1.124, 1.178). Average exposure to PM 10 was associated with non-accidental mortality in patients with COPD, especially those diagnosed with ACO. In addition, the adverse effects of PM 10 exposure are more severe in women and never-smokers.

Ventilation heterogeneity is frequent in bronchial asthma and can be assessed using multiple breath wash-out testing (MBW). Most data is available in paediatric patients and using nitrogen as a tracer gas. We aimed to evaluate sulphur hexafluoride (SF 6 ) MBW in adult asthmatics. Spirometry, whole-body plethysmography, impulse oscillometry and SF 6 -MBW were prospectively performed. MBW parameters reflecting global (lung clearance index, LCI), acinar (S acin ) and conductive (S cond ) ventilation heterogeneity were derived from three consecutive wash-outs. LCI was calculated for the traditional 2.5% and an earlier 5% stopping point that has the potential to reduce wash-out times. 91 asthmatics (66%) and 47 non-asthmatic controls (34%) were included in final analysis. LCI 2.5 and LCI 5 were higher in asthmatics (p < 0.001). Likewise, S acin and S cond were elevated (p < 0.001 and p < 0.01). Coefficient of variation was 3.4% for LCI 2.5 and 3.5% for LCI 5 in asthmatics. Forty-one asthmatic patients had normal spirometry. ROC analysis revealed an AUC of 0.906 for the differentiation from non-asthmatic controls exceeding diagnostic performance of individual and conventional parameters (AUC = 0.819, p < 0.05). SF 6 -MBW is feasible and reproducible in adult asthmatics. Ventilation heterogeneity is increased as compared to non-asthmatic controls persisting in asthmatic patients with normal spirometry. Diagnostic performance is not affected using an earlier LCI stopping point while reducing wash-out duration considerably.

DNA methylation (DNAm) profiles in central airway epithelial cells (AECs) may play a key role in pathological processes in asthma. The goal of the current study is to compare the diagnostic performance of DNAm markers across three tissues: AECs, nasal epithelial cells (NECs), and peripheral blood mononuclear cells (PBMCs). Additionally, we focused on the results using the machine learning algorithm in the context of multi-locus effects to evaluate the diagnostic performance of the optimal subset of CpG sites. We obtained 74 subjects with asthma and 41 controls from AECs, 15 subjects with asthma and 14 controls from NECs, 697 subjects with asthma and 97 controls from PBMCs. Epigenome-wide DNA methylation levels in AECs, NECs and PBMCs were measured using the Infinium Human Methylation 450 K BeadChip. Overlap analysis across the three different sample sources at the locus and pathway levels were studied to investigate shared or unique pathophysiological processes of asthma across tissues. Using the top 100 asthma-associated methylation markers as classifiers from each dataset, we found that both AEC- and NEC-based DNAm signatures exerted a lower classification error than the PBMC-based DNAm markers (p-value = 0.0002). The area-under-the-curve (AUC) analysis based on out-of-bag errors using the random forest classification algorithm revealed that PBMC-, NEC-, and AEC-based methylation data yielded 31 loci (AUC: 0.87), 8 loci (AUC: 0.99), and 4 loci (AUC: 0.97) from each optimal subset of tissue-specific markers, respectively. We also discovered the locus-locus interaction of DNAm levels of the CDH6 gene and RAPGEF3 gene might interact with each other to jointly predict the risk of asthma - which suggests the pivotal role of cell-cell junction in the pathological changes of asthma. Both AECs and NECs might provide better diagnostic accuracy and efficacy levels than PBMCs. Further research is warranted to evaluate how these tissue-specific DNAm markers classify and predict asthma risk.

In COPD, epithelial changes are prominent features in the airways, such as goblet cell hyperplasia and squamous metaplasia. In contrast, it remains unclear whether ciliated cells are reduced and which pathways dysregulate epithelial differentiation. We hypothesized that bronchial epithelial cell lineage specification is dysregulated in COPD because of an aberrant reprogramming through transforming growth factor (TGF)-β1. Surgical lung tissue from 81 COPD and 61 control (smokers and non-smokers) patients was assessed for bronchial epithelial cell phenotyping by immunohistochemistry, both in situ and in vitro in reconstituted air-liquid interface (ALI) cultures. The role of TGF-β1 was studied in vitro. COPD epithelium in large airways, when compared to controls, showed decreased β-tubulin IV + ciliated cells (4.4%, 2.5–8.8% versus 8.5%, 6.3–11.8% of surface staining, median and IQR, p = 0.0009) and increased MUC5AC + goblet cells (34.8%, 24.4–41.9% versus 10.3%, 5.1–17.6%, p < 0.0001). Both features were recapitulated in the ALI-cultured epithelium from COPD patients. Exogenous TGF-β1 reduced mucociliary differentiation while neutralizing TGF-β1 during ALI increased both specialized cell types. The COPD airway epithelium displays altered differentiation for ciliated cells, which recapitulates in vitro, at least in part through TGF-β1. [ABSTRACT FROM AUTHOR]

Asthma is a common chronic lung disease, the incidence and severity of which may be influenced by gene-environment interactions. Our objective was to examine associations between single nucleotide polymorphisms (SNPs) and combinations of SNPs in the toll-like receptor 4 (TLR4) pathway, residential distance to roadway as a proxy for traffic-related air pollution exposure, and asthma diagnosis and exacerbations. We obtained individual-level data on genotype, residential address, and asthma diagnosis and exacerbations from the Environmental Polymorphisms Registry. Subjects (n = 2,704) were divided into three groups (hyper-responders, hypo-responders, and neither) based on SNP combinations in genes along the TLR4 pathway. We geocoded subjects and calculated distance, classified as <250 m or ≥250 m, between residence and nearest major road. Relationships between genotype, distance to road, and odds of asthma diagnosis and exacerbations were examined using logistic regression. Odds of an asthma diagnosis among hyper-responders <250 m from a major road was 2.37(0.97, 6.01) compared to the reference group (p < 0.10). Hypo-responders ≥250 m from the nearest road had lower odds of activity limitations (0.46 [0.21, 0.95]) and sleeplessness (0.36 [0.12, 0.91]) compared to neither-responders (p < 0.05). Specific genotype combinations when combined with an individual’s proximity to roadways, possibly due to traffic-related air pollution exposure, may affect the likelihood of asthma diagnosis and exacerbations. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) constitutes a major health burden. Studying underlying molecular mechanisms could lead to new therapeutic targets. Macrophages are orchestrators of COPD, by releasing pro-inflammatory cytokines. This process relies on transcription factors such as NF-κB, among others. NF-κB is regulated by lysine acetylation; a post-translational modification installed by histone acetyltransferases and removed by histone deacetylases (HDACs). We hypothesized that small molecule HDAC inhibitors (HDACi) targeting class I HDACs members that can regulate NF-κB could attenuate inflammatory responses in COPD via modulation of the NF-κB signaling output. MS-275 is an isoform-selective inhibitor of HDAC1-3. In precision-cut lung slices and RAW264.7 macrophages, MS-275 upregulated the expression of both pro- and anti-inflammatory genes, implying mixed effects. Interestingly, anti-inflammatory IL10 expression was upregulated in these model systems. In the macrophages, this was associated with increased NF-κB activity, acetylation, nuclear translocation, and binding to the IL10 promoter. Importantly, in an in vivo model of cigarette smoke-exposed C57Bl/6 mice, MS-275 robustly attenuated inflammatory expression of KC and neutrophil influx in the lungs. This study highlights for the first time the potential of isoform-selective HDACi for the treatment of inflammatory lung diseases like COPD. [ABSTRACT FROM AUTHOR]

Inhaled corticosteroids (ICSs) are widely prescribed in chronic obstructive pulmonary disease (COPD). However, little is known about predictors of ICSs therapeutic response. To investigate whether the variation in glucocorticoid-induced transcript 1 (GLCCI1) rs37973 is associated with ICS efficacy. A total of 204 clinically stable COPD patients were recruited and administered to inhaled fluticasone propionate/salmeterol combination (500/50 ug, twice daily) for 24 weeks. We genotyped the functional rs37973 and mainly assessed its effects on changes in lung function. In vitro, neutrophils isolated from parts of patients were incubated with various concentrations of dexamethasone (0, 10−6 M and 10−4 M) in the presence or absence of cigarette smoke extract, apoptosis was then assessed by flow cytometry. Patients with the homozygous GG genotype (increases of 15.3 ± 33.2 mL) had significantly poorer improvement in FEV1 than those with the AA (92.7 ± 29.6 mL; p < 0.001) or AG (59.4 ± 26.9 mL; p < 0.001) genotypes after 24-week treatment. In vitro, dexamethasone had less inhibitory effect of neutrophil apoptosis on GG genotype, which further validated the presence of mutant allele 'G' might negatively affect glucocorticoid responsiveness irrespective of smoking status. The GG genotype of rs37973 may associated with decreased ICSs efficacy in Chinese COPD patients. [ABSTRACT FROM AUTHOR]

Loss of airway epithelial integrity contributes significantly to asthma pathogenesis. Thymic stromal lymphopoietin (TSLP) may have dual immunoregulatory roles. In inflammatory disorders of the bowel, the long isoform of TSLP (lfTSLP) promotes inflammation while the short isoform (sfTSLP) inhibits inflammation. We hypothesize that lfTSLP contributes to house dust mite (HDM)-induced airway epithelial barrier dysfunction and that synthetic sfTSLP can prevent these effects. In vitro, airway epithelial barrier function was assessed by monitoring transepithelial electrical resistance, fluorescent-dextran permeability, and distribution of E-cadherin and β-catenin. In vivo, BALB/c mice were exposed to HDM by nasal inhalation for 5 consecutive days per week to establish an asthma model. sfTSLP and 1α,25-Dihydroxyvitamin D3 (1,25D3) were administered 1 h before HDM exposure. After 8 weeks, animal lung function tests and pathological staining were performed to evaluate asthma progression. We found that HDM and lfTSLP impaired barrier function. Treatment with sfTSLP and 1,25D3 prevented HDM-induced airway epithelial barrier disruption. Moreover, sfTSLP and 1,25D3 treatment ameliorated HDM-induced asthma in mice. Our data emphasize the importance of the different expression patterns and biological properties of sfTSLP and lfTSLP. Moreover, our results indicate that sfTSLP and 1,25D3 may serve as novel therapeutic agents for individualized treatment of asthma. [ABSTRACT FROM AUTHOR]