Bronchoalveolar Lavage Fluid Markers Research Articles

Key inflammatory markers in bronchoalveolar lavage predict bronchiectasis progression in young children with CF

IntroductionInflammation appears early in cystic fibrosis (CF) pathogenesis, with specific elevated inflammatory markers in bronchoalveolar lavage fluid (BALF) correlating with structural lung disease.Our aim was to identify markers of airway inflammation able to predict bronchiectasis progression over two years with high sensitivity and specificity. MethodsChildren with CF with two chest computed tomography (CT) scans and bronchoscopies at a two-year interval were included (n= 10 at 1 and 3 years and n= 27 at 3 and 5 years). Chest CTs were scored for increase in bronchiectasis (Δ%Bx), using the PRAGMA-CF score. BALF collected with the first CT scan were analyzed for neutrophil% (n= 36), myeloperoxidase (MPO) (n= 25), neutrophil elastase (NE) (n= 26), and with a protein array for inflammatory and fibrotic markers (n= 26). ResultsMPO, neutrophil%, and inducible T-cell costimulator ligand (ICOSLG), but not clinical characteristics, correlated significantly with Δ%Bx. Evaluation of neutrophil%, NE, MPO, interleukin-8 (IL-8), ICOSLG, and hepatocyte growth factor (HGF), for predicting an increase of > 0.5% of Δ%Bx in two years, showed that IL-8 had the best sensitivity (82%) and specificity (73%). Neutrophil%, ICOSLG and HGF had sensitivities of 85, 82, and 82% and specificities of 59, 67 and 60%, respectively. The odds ratio for risk of >0.5% Δ%Bx was higher for IL-8 (12.4) than for neutrophil%, ICOSLG, and HGF (5.9, 5.3, and 6.7, respectively). Sensitivity and specificity were lower for NE and MPO). ConclusionsHigh levels of IL-8, neutrophil%, ICOSGL and HGF in BALF may be good predictors for progression of bronchiectasis in young children with CF.

Serum and Bronchoalveolar Lavage Fluid Levels of Cytokines in Patients with Lung Cancer and Chronic Lung Disease: A Prospective Comparative Study.

The role of chronic inflammation in the initiation and progression of carcinogenesis has been well-established in previous studies, particularly in the stages of malignant conversion, invasion, and metastasis. This study aimed to explore the potential correlation between the levels of cytokines in serum and bronchoalveolar lavage fluid (BALF) by comparing their levels between patients with lung cancer and those with benign lung diseases. The study measured the concentration of IFN-γ, TNF-α, IL-1β, IL-2, IL-4, IL-6, IL-10, and IL-12p70, in venous blood and BALF of a total of 33 patients with lung cancer and 33 patients with benign lung diseases. Significant differences were found between the two groups in various clinical parameters. The cytokine levels were significantly higher among patients with malignant disease, while the BALF analysis revealed higher cytokine levels compared with serum analysis. It was discovered that the levels of cancer-specific cytokines in the lavage fluid increased significantly sooner and were present at a greater concentration than those in the peripheral blood. After one month of treatment, the serum markers decreased significantly but slower in the lavage fluid. The differences between serum and BALF markers remained significant. It was observed that the highest correlation was among IL-6 (serum) and IL-6 (lavage), with a coefficient of 0.774 (p-value < 0.001), and IL-1 (serum) and IL-1β (lavage), with a coefficient value of 0.610 (p-value < 0.001). Other significant correlations among serum and lavage cytokines were observed between IL-6 (lavage) and IL-1 (serum) (rho = 0.631, p-value < 0.001) and CRP (rho = 0.428, p-value = 0.001), respectively. This study revealed significant differences and correlations in clinical parameters, serum markers, and BALF inflammatory markers between patients with lung cancer and those with benign lung pathologies. The results highlight the importance of understanding the inflammatory profiles of these conditions and could contribute to the development of targeted therapies or diagnostic approaches in the future. Further research is needed to validate these findings, explore their implications for clinical practice, and determine the diagnostic and prognostic value of these cytokines for lung cancer.

The Association of IFN-γ, TNF-α, and Interleukins in Bronchoalveolar Lavage Fluid with Lung Cancer: A Prospective Analysis.

Lung cancer is a leading cause of cancer-related mortality worldwide. Identifying novel diagnostic and prognostic biomarkers is essential for improving patient outcomes. This study aimed to investigate the predictive role of cytokines from bronchoalveolar lavage fluid (BALF) in lung cancer diagnosis and prognosis. A prospective study was conducted on 33 patients with suspected lung cancer, divided into inflammatory and non-inflammatory BALF groups. Inflammatory markers in BALF were assessed, and their association with lung cancer risk was analyzed using receiver operating characteristic (ROC) plot analysis, sensitivity and specificity percentages, and regression analysis. Statistically significant differences were observed between the inflammatory and non-inflammatory groups for several inflammatory markers, including IFN-gamma, IL-1b, IL-2, IL-6, IL-10, and IL-12p70. In the follow-up analysis, significant differences persisted for IFN-gamma, IL-1b, IL-2, IL-4, and IL-6. ROC plot analysis revealed that IL-12p70 had the highest area under the curve (AUC) value (0.702), followed by IL-2 (0.682), IL-6 (0.620), IL-4 (0.611), TNF-alpha (0.609), IL-10 (0.604), IL-1b (0.635), and IFN-gamma (0.521). IL-6 showed the highest sensitivity (73%), and IL-1b had the highest specificity (69%). Regression analysis demonstrated that IL-6 (cut-off = 25 pg/mL) and IL-12p70 (cut-off = 30 pg/mL) had the highest odds ratios for lung cancer risk, at 5.09 (95% CI: 2.38-9.24, p < 0.001) and 4.31 (95% CI: 1.85-8.16, p < 0.001), respectively. Cytokines from BALF, particularly IL-6 and IL-12p70, show potential as diagnostic and prognostic biomarkers for lung cancer. Further studies with larger cohorts are warranted to confirm these findings and elucidate the clinical implications of these markers in lung cancer management.

Identification of Virulence Factors Involved in a Murine Model of Severe Achromobacter xylosoxidans Infection.

Achromobacter xylosoxidans (Ax) is an opportunistic pathogen and causative agent of numerous infections particularly in immunocompromised individuals with increasing prevalence in cystic fibrosis (CF). To date, investigations have focused on the clinical epidemiology and genomic comparisons of Ax isolates, yet little is known about disease pathology or the role that specific virulence factors play in tissue invasion or damage. Here, we model an acute Ax lung infection in immunocompetent C57BL/6 mice and immunocompromised CF mice, revealing a link between in vitro cytotoxicity and disease in an intact host. Mice were intratracheally challenged with sublethal doses of a cytotoxic (GN050) or invasive (GN008) strain of Ax. Bacterial burden, immune cell populations, and inflammatory markers in bronchoalveolar lavage fluid and lung homogenates were measured at different time points to assess disease severity. CF mice had a similar but delayed immune response toward both Ax strains compared to C57BL/6J mice. GN050 caused more severe disease and higher mortality which correlated with greater bacterial burden and increased proinflammatory responses in both mouse models. In agreement with the cytotoxicity of GN050 toward macrophages in vitro, mice challenged with GN050 had fewer macrophages. Mutants with transposon insertions in predicted virulence factors of GN050 showed that disease severity depended on the type III secretion system, Vi capsule, antisigma-E factor, and partially on the ArtA adhesin. The development of an acute infection model provides an essential tool to better understand the infectivity of diverse Ax isolates and enable improved identification of virulence factors important to bacterial persistence and disease.

Fungal Tracheobronchitis in Lung Transplant Recipients: Incidence and Utility of Diagnostic Markers.

Fungal tracheobronchitis caused by Aspergillus and Candida spp. is a recognized complication after lung transplantation, but knowledge of the incidence of Candida tracheobronchitis is lacking. The diagnosis relies on fungal cultures in bronchoalveolar lavage fluid (BALF), but cultures have low specificity. We aimed to evaluate the one-year incidence of fungal tracheobronchitis after lung transplantation and to assess the utility of diagnostic markers in serum and BALF to discriminate fungal tracheobronchitis from colonization. Ninety-seven consecutively included adult lung-transplant recipients were prospectively followed. BALF and serum samples were collected at 1, 3 and 12 months after transplantation and analyzed for betaglucan (serum and BALF), neutrophils (BALF) and galactomannan (BALF). Fungal tracheobronchitis was defined according to consensus criteria, modified to include Candida as a mycologic criterion. The cumulative one-year incidence of Candida and Aspergillus tracheobronchitis was 23% and 16%, respectively. Neutrophils of &gt;75% of total leukocytes in BALF had 92% specificity for Candida tracheobronchitis. The area under the ROC curves for betaglucan and galactomannan in BALF to discriminate Aspergillus tracheobronchitis from colonization or no fungal infection were high (0.86 (p &lt; 0.0001) and 0.93 (p &lt; 0.0001), respectively). To conclude, the one-year incidence of fungal tracheobronchitis after lung transplantation was high and dominated by Candida spp. Diagnostic markers in BALF could be useful to discriminate fungal colonization from tracheobronchitis.

Volutrauma Increases Exhaled Pentanal in Rats: A Potential Breath Biomarker for Ventilator-Induced Lung Injury.

Mechanical ventilation injures lungs, but there are currently no reliable methods for detecting early injury. We therefore evaluated whether exhaled pentanal, a lipid peroxidation product, might be a useful breath biomarker for stretch-induced lung injury in rats. A total of 150 male Sprague-Dawley rats were investigated in 2 substudies. The first randomly assigned 75 rats to 7 hours of mechanical ventilation at tidal volumes of 6, 8, 12, 16, and 20 mL·kg-1. The second included 75 rats. A reference group was ventilated at a tidal volume of 6 mL·kg-1 for 10 hours 4 interventional groups were ventilated at a tidal volume of 6 mL·kg-1 for 1 hour, and then for 0.5, 1, 2, or 3 hours at a tidal volume of 16 mL.kg-1 before returning to a tidal volume of 6 mL·kg-1 for additional 6 hours. Exhaled pentanal was monitored by multicapillary column-ion mobility spectrometry. The first substudy included cytokine and leukocyte measurements in blood and bronchoalveolar fluid, histological assessment of the proportion of alveolar space, and measurements of myeloperoxidase activity in lung tissue. The second substudy included measurements of pentanal in arterial blood plasma, cytokine and leukocyte concentrations in bronchoalveolar fluid, and cleaved caspase 3 in lung tissue. Exhaled pentanal concentrations increased by only 0.5 ppb·h-1 (95% confidence interval [CI], 0.3-0.6) when rats were ventilated at 6 mL·kg-1. In contrast, exhaled pentanal concentrations increased substantially and roughly linearly at higher tidal volumes, up to 3.1 ppb·h-1 (95% CI, 2.3-3.8) at tidal volumes of 20 mL·kg-1. Exhaled pentanal increased at average rates between 1.0 ppb·h-1 (95% CI, 0.3-1.7) and 2.5 ppb·h-1 (95% CI, 1.4-3.6) after the onset of 16 mL·kg-1 tidal volumes and decreased rapidly by a median of 2 ppb (interquartile range [IQR], 0.9-3.2), corresponding to a 38% (IQR, 31-43) reduction when tidal volume returned to 6 mL·kg-1. Tidal volume, inspiratory pressure, and mechanical power were positively associated with pentanal exhalation. Exhaled and plasma pentanal were uncorrelated. Alveolar space decreased and inflammatory markers in bronchoalveolar lavage fluid increased in animals ventilated at high tidal volumes. Short, intermittent ventilation at high tidal volumes for up to 3 hours increased neither inflammatory markers in bronchoalveolar fluid nor the proportion of cleaved caspase 3 in lung tissue. Exhaled pentanal is a potential biomarker for early detection of ventilator-induced lung injury in rats.

Pulmonary toxicity and gene expression changes after short-term inhalation exposure to surface-modified copper oxide nanoparticles

Copper oxide nanoparticles (CuO NPs) have previously been shown to cause dose-dependent pulmonary toxicity following inhalation. Here, CuO NPs (10 nm), coated with polyethylenimine (PEI) or ascorbate (ASC) resulting in positively or negatively charged NPs, respectively, were evaluated. Rats were exposed nose-only to similar exposure dose levels of ASC or PEI coated CuO NPs for 5 consecutive days. On day 6 and day 27 post-exposure, pulmonary toxicity markers in bronchoalveolar lavage fluid (BALF), lung histopathology and genome-wide transcriptomic changes in lungs, were assessed. BALF analyses showed a dose-dependent pulmonary inflammation and cell damage, which was supported by the lung histopathological findings of hypertrophy/hyperplasia of bronchiolar and alveolar epithelium, interstitial and alveolar inflammation, and paracortical histiocytosis in mediastinal lymph nodes for both types of CuO NPs. Transcriptomics analysis showed that pathways related to inflammation and cell proliferation were significantly activated. Additionally, we found evidence for the dysregulation of drug metabolism-related genes, especially in rats exposed to ASC-coated CuO NPs. Overall, no differences in the type of toxic effects and potency between the two surface coatings could be established, except with respect to the (regional) dose that initiates bronchiolar and alveolar hypertrophy. This disproves our hypothesis that differences in surface coatings affect the pulmonary toxicity of CuO NPs.

Multi-omics links IL-6 trans-signalling with neutrophil extracellular trap formation and Haemophilus infection in COPD.

Interleukin (IL)-6 trans-signalling (IL-6TS) is emerging as a pathogenic mechanism in chronic respiratory diseases; however, the drivers of IL-6TS in the airways and the phenotypic characteristic of patients with increased IL-6TS pathway activation remain poorly understood. Our aim was to identify and characterise COPD patients with increased airway IL-6TS and to elucidate the biological drivers of IL-6TS pathway activation. We used an IL-6TS-specific sputum biomarker profile (soluble IL-6 receptor (sIL-6R), IL-6, IL-1β, IL-8, macrophage inflammatory protein-1β) to stratify sputum data from patients with COPD (n=74; Biomarkers to Target Antibiotic and Systemic Corticosteroid Therapy in COPD Exacerbation (BEAT-COPD)) by hierarchical clustering. The IL-6TS signature was related to clinical characteristics and sputum microbiome profiles. The induction of neutrophil extracellular trap formation (NETosis) and IL-6TS by Haemophilus influenzae were studied in human neutrophils. Hierarchical clustering revealed an IL-6TS-high subset (n=24) of COPD patients, who shared phenotypic traits with an IL-6TS-high subset previously identified in asthma. The subset was characterised by increased sputum cell counts (p=0.0001), persistent sputum neutrophilia (p=0.0004), reduced quality of life (Chronic Respiratory Questionnaire total score; p=0.008), and increased levels of pro-inflammatory mediators and matrix metalloproteinases in sputum. IL-6TS-high COPD patients showed an increase in Proteobacteria, with Haemophilus as the dominating genus. NETosis induced by H. influenzae was identified as a potential mechanism for increased sIL-6R levels. This was supported by a significant positive correlation between sIL-6R and NETosis markers in bronchoalveolar lavage fluid from COPD patients. IL-6TS pathway activation due to chronic colonisation with Haemophilus may be an important disease driver in a subset of COPD patients.

DSPE-PEG polymers for improving pulmonary absorption of poorly absorbed macromolecules in rats and relative mechanism

Objective This study aims to investigate the potential of DSPE-PEG polymers (DSPE-PEG-OH and DSPE-PEG-SH) on improving absorption of poorly absorbable macromolecules via intrapulmonary administration and underlying mechanism. Methods In situ pulmonary absorption experiments were performed to investigate the absorption of model compounds after intrapulmonary administration to rats. The local membrane damage induced by these DSPE-PEG polymers were evaluated based on morphological observation of lung tissues and measurement of biological toxic markers in bronchoalveolar lavage fluid (BALF) postintrapulmonary delivery of DSPE-PEG polymers to rats. The underlying enhancement mechanism of these polymers was explored by investigating their effects on the pulmonary membrane fluidity and gene expression of tight junction associated proteins with fluorescence polarization and western blotting, respectively. Results Intrapulmonary delivery of these DSPE-PEG polymers significantly enhanced absorptions of poorly absorbed model drugs and did not induce serious damage to the pulmonary membranes of rats. Mechanistic studies demonstrated unaffected pulmonary membrane fluidity and up-regulated expression levels of tight junction-associated proteins by DSPE-PEG polymers, thus indicating that paracellular pathways might be included in the underlying mechanisms by which DSPE-PEG polymers exerted their enhancing actions on drug absorption. Conclusions These findings suggested that these DSPE-PEG polymers are potential for promoting absorptions of poorly absorbable macromolecules with no evidence of damage to the local pulmonary membranes of rats. Novelty statement In this study, DSPE-PEG-OH and DSPE-PEG-SH polymers, two DSPE-PEG2000 conjugates with different terminal groups demonstrated significant promoting effects on the absorption of poorly absorbed macromolecular drugs after intrapulmonary delivery to rats, and did not induce serious damage to the pulmonary membranes of rats. These DSPE-PEG polymers could statistically downregulate expression levels of tight junction-associated proteins (ZO-1 and occludin), indicating the underlying mechanism by which these polymers exerted their absorption enhancing actions through pulmonary epithelial paracellular pathways. Thus, this study exhibited prospective potential of these DSPE-PEG polymers in developing into dosage forms with the aim to improve the poor bioavailability of some poorly absorbed macromolecular drugs.

Bile Acid Signal Molecules Associate Temporally with Respiratory Inflammation and Microbiome Signatures in Clinically Stable Cystic Fibrosis Patients

Cystic fibrosis (CF) is a congenital disorder resulting in a multisystemic impairment in ion homeostasis. The subsequent alteration of electrochemical gradients severely compromises the function of the airway epithelia. These functional changes are accompanied by recurrent cycles of inflammation–infection that progressively lead to pulmonary insufficiency. Recent developments have pointed to the existence of a gut–lung axis connection, which may modulate the progression of lung disease. Molecular signals governing the interplay between these two organs are therefore candidate molecules requiring further clinical evaluation as potential biomarkers. We demonstrate a temporal association between bile acid (BA) metabolites and inflammatory markers in bronchoalveolar lavage fluid (BALF) from clinically stable children with CF. By modelling the BALF-associated microbial communities, we demonstrate that profiles enriched in operational taxonomic units assigned to supraglottic taxa and opportunistic pathogens are closely associated with inflammatory biomarkers. Applying regression analyses, we also confirmed a linear link between BA concentration and pathogen abundance in BALF. Analysis of the time series data suggests that the continuous detection of BAs in BALF is linked to differential ecological succession trajectories of the lung microbiota. Our data provide further evidence supporting a role for BAs in the early pathogenesis and progression of CF lung disease.

Assessment of Cytokine-Induced Neutrophil Chemoattractants as Biomarkers for Prediction of Pulmonary Toxicity of Nanomaterials.

This work determines whether cytokine-induced neutrophil chemoattractants (CINC)-1, CINC-2 and CINC-3 can be markers for predicting high or low pulmonary toxicity of nanomaterials (NMs). We classified NMs of nickel oxide (NiO) and cerium dioxide (CeO2) into high toxicity and NMs of two types of titanium dioxides (TiO2 (P90 and rutile)) and zinc oxide (ZnO) into low toxicity, and we analyzed previous data of CINCs in bronchoalveolar lavage fluid (BALF) of rats from three days to six months after intratracheal instillation (0.2 and 1.0 mg) and inhalation exposure (0.32–10.4 mg/m3) of materials (NiO, CeO2, TiO2 (P90 and rutile), ZnO NMs and micron-particles of crystalline silica (SiO2)). The concentration of CINC-1 and CINC-2 in BALF had different increase tendency between high and low pulmonary toxicity of NMs and correlated with the other inflammatory markers in BALF. However, CINC-3 increased only slightly in a dose-dependent manner compared with CINC-1 and CINC-2. Analysis of receiver operating characteristics for the toxicity of NMs by CINC-1 and CINC-2 showed the most accuracy of discrimination of the toxicity at one week or one month after exposure and CINC-1 and CINC-2 in BALF following intratracheal instillation of SiO2 as a high toxicity could accurately predict the toxicity at more than one month after exposure. These data suggest that CINC-1 and CINC-2 may be useful biomarkers for the prediction of pulmonary toxicity of NMs relatively early in both intratracheal instillation and inhalation exposure.

Restoration of HDAC2 and Nrf2 by andrographolide overcomes corticosteroid resistance in chronic obstructive pulmonary disease.

Corticosteroid resistance poses a major barrier to an effective anti-inflammatory therapy for chronic obstructive pulmonary disease (COPD). The present study aimed to investigate potential corticosteroid re-sensitization actions of andrographolide, a bioactive molecule from the herb Andrographis paniculata, in COPD models, particularly in peripheral blood mononuclear cells (PBMCs) from COPD patients. Corticosteroid sensitivity in PBMCs collected from COPD patients, or in human monocytic U937 cells exposed to cigarette smoke extract (CSE), was determined by measuring LPS-induced IL-8 production, in the presence and absence of andrographolide. The mechanisms of corticosteroid re-sensitization action of andrographolide were evaluated in a mouse cigarette smoke (CS)-induced acute lung injury model. Impaired inhibition of IL-8 production by dexamethasone was detected in PBMCs from COPD patients and in CSE-exposed U937 cells, together with reduced levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and histone deacetylase-2 (HDAC2). In both PBMCs and CSE-exposed U937 cells, andrographolide restored dexamethasone inhibition of IL-8 production, accompanied by the up-regulation of Nrf2 and HDAC2 levels. In the U937 cells, andrographolide was able to block CSE-induced Akt and reduce the level of c-Jun. Besides, andrographolide also augmented dexamethasone actions on lowering total and neutrophil counts, cytokine levels, and oxidative damage markers in bronchoalveolar lavage fluid from CS-exposed mice. We report here for the first time a novel corticosteroid re-sensitization property of andrographolide in human PBMCs and provide mechanistic evidence to support clinical evaluation of andrographolide in reversing steroid resistance in COPD.

Effect of different treatments on macrophage differentiation in chronic obstructive pulmonary disease and repeated pulmonary infection.

ObjectiveTo observe the differentiation of macrophages in lung tissue and alveolar lavage fluid of mice with severe pulmonary infection and the changes after intervention with ceftriaxone and ulinastatin, and to explore the pathogenesis of severe pulmonary infection under immunosuppressive state and the intervention effect of two drugs.Methods40 male Balb/c mice are randomly divided into normal group, model group, ulinastatin group, and ceftriaxone group with 10 mice in each group. Mice models of acute lung injury with immunodeficiency are established by methylprednisolone and endotoxin, and then treated with ulinastatin and ceftriaxone. Respiratory frequencies of mice in each group are measured at 3 h and 6 h after drug use through trachea, and then the mice are anaesthetized with uratan and killed 6 h after drug use. The number of alveolar macrophages and neutrophils in alveolar lavage fluid is collected and detected, and the pathological changes are observed. The positive expression of CD163 in lung tissue is detected by IHC (immunohistochemistry), and real-time quantitative PCR (Polymerase Chain Reaction) is used to detect the expression of Ml and M2 markers in bronchoalveolar lavage fluid (BALF).ResultCompared with the normal group, the mice in the model group breathed shallowly and quickly, occasionally nodded breathing, respiratory distress, and respiratory rate increased. Compared with the model group, the mice in the ulinastatin group and ceftriaxone group breathed slowly, occasionally have shortness of breath, smooth breathing, and slow breathing rate, and the mice in ulinastatin group breathe more smoothly. The number of macrophages and neutrophils in BALF of model group is higher than that of normal group. The number of macrophages and neutrophils in ulinastatin group and ceftriaxone group is lower than that of model group and the difference is statistically significant, and the number of macrophages and neutrophils in ulinastatin group is relatively less than that in model group.ConclusionIn the early stage of severe pulmonary infection under immunosuppressive state, the organism is in the CARS (Compensatory Anti-inflammatory Response Syndrome) stage; M1 macrophages had immune paralysis and M2 macrophages are abnormally activated. Compared with ceftriaxone, ulinastatin can alleviate lung injury more effectively and protect the lung of mice with acute lung injury. The protective mechanism of ulinastatin on lung of mice infected with immunocompromised endotoxin may be through inhibiting M1 macrophages and regulating non-specific immune function.

Pulmonary Microbiome Changes in Lung Transplant Recipients with Gastroesophageal Reflux

The pulmonary microbiome modulates the immune milieu in the lung allograft and is in turn influenced by external factors such as microaspiration of oropharyngeal contents. A potential driver of microaspiration is gastroesophageal reflux disease (GERD), which has been associated with poor outcomes after lung transplantation. We aimed to compare the pulmonary microbiome in lung transplant recipients with and without GERD, and correlate microbial composition with concurrent lung inflammation. We selected 22 GERD patients and 49 no-GERD controls from adult lung transplant recipients with 24-hour pH-impedance testing and bronchoalveolar lavage fluid (BAL) collection at 3 months post-transplant. BAL microbial communities were characterized by 16S rRNA gene sequencing. Ten inflammatory protein markers in BAL were measured by multiplex assay. Baseline patient characteristics including age, sex, primary disease, and transplant type were comparable between GERD and no-GERD groups. Shannon diversity index was lower (MD=-0.33, p=0.04), while Berger-Parker dominance index was higher (MD=0.10, p=0.03), in GERD patients compared to no-GERD controls. Hierarchical clustering of all samples by Bray-Curtis dissimilarity identified three distinct pneumotypes (Figure 1). GERD was significantly associated with one of these pneumotypes, PT1, which was enriched in multiple anaerobic oropharyngeal taxa including Prevotella and Veillonella. In GERD patients, the presence of PT1 compared to all others was associated with higher levels of IL-8 (p=0.03). At time of GERD diagnosis, lung transplant recipients are more likely to have a pulmonary microbiome lower in diversity and enriched in oropharyngeal taxa. These perturbations are consistent with microaspiration and may contribute to allograft inflammation. Future studies are warranted to assess how the pulmonary microbiome changes over time in the context of GERD and its correlation with rejection and long-term outcomes.

Efficacy of SPM-NONOate following intrapulmonary delivery in promoting absorptions of poorly absorbed macromolecules in rats and the underling mechanism.

This research aims to investigate the potential of N-[4-[1-(3-Aminopropyl)-2-hydroxy-2-nitrosohydrazino]butyl]-1,3-propanediamine (SPM-NONOate) for promoting the absorption of poorly absorbed macromolecules delivered by intrapulmonary route. Influence of SPM-NONOate on the drug absorption was characterized by using a series of fluorescein isothiocyanate-labeled dextrans (FDs) as affordable models of hydrophilic macromolecules with established tools for quantitative analysis. SPM-NONOate increased concentration-dependently within 1-10mM the pulmonary absorptions of FDs in rats. Moreover, this promoting effect varied with the molecular weight of FDs, and the largest absorption enhancement effect was obtained for FD70. SPM-NONOate also showed promising enhancement potential on the absorption of some therapeutic peptides, where obvious hypoglycemic and hypocalcemic effects were observed after intrapulmonary delivery of insulin and calcitionin, respectively, with SPM-NONOate to rats. The safety of SPM-NONOate was confirmed based on measurement of some biological markers in bronchoalveolar lavage fluid (BALF) of rats. Additionally, mechanism underling the absorption enhancement action of SPM-NONOate was explored by combinatorial administration of FD4 and SPM-NONOate with various scavengers and generator to rat lungs. Results indicated that NO released from SPM-NONOate induced the enhancement in the drug absorption, and peroxynitrate, a NO metabolite, possibly participated in the absorption enhancing action of SPM-NONOate.

Rosuvastatin Affects Tracheal Responsiveness, Bronchoalveolar Lavage Inflammatory Cells, and Oxidative Stress Markers in Hyperlipidemic and Asthmatic Rats.

Statins provide greater protection than predicted from just cholesterol-lowering effects, which is possibly mediated by other pleiotropic actions. This study aimed to examine the possible interaction effect of asthma on lipid profiles and evaluate the effect of rosuvastatin treatment on asthma. The animals were assigned into (1) control, (2) asthmatic, (3) hyperlipidemic, (4) asthmatic-hyperlipidemic, (5) rosuvastatin (40 mg/kg/day intraperitoneally, for 3 weeks)-treated asthmatic, (6) rosuvastatin-treated hyperlipidemic and (7) rosuvastatin-treated asthmatic-hyperlipidemic groups. Tracheal responsiveness to methacholine and ovalbumin, total and differential WBC (white blood cell) counts, and oxidative stress markers in bronchoalveolar lavage fluid (BALF) were evaluated. In the asthmatic and asthmatic-hyperlipidemic groups, tracheal responsiveness to ovalbumin, total WBC count, numbers of eosinophils, neutrophils, and monocytes were higher than the control group (p<0.001). A left-ward shift in the concentration-response curves to methacholine, an increase in nitrite and malondialdehyde concentrations, and a decrease in total thiol content, superoxide dismutase and catalase activities were also observed in the asthmatic and asthmatic-hyperlipidemic groups compared to control group (p<0.01 to p<0.001). Beyond lipid-lowering effect in the treated hyperlipidemic and asthmatic-hyperlipidemic groups, rosuvastatin treatment decreased tracheal responsiveness to methacholine, reduced total WBC count, the numbers of eosinophils, neutrophils, and monocytes, as well as decreased malondialdehyde concentration, and increased total thiol content, superoxide dismutase and catalase activities in treated asthmatic and asthmatic-hyperlipidemic groups (p<0.05 to p<0.001). The improving effect of rosuvastatin on asthmatic and asthmatic-hyperlipidemic animals was shown due to pleiotropic mechanisms including the effect on airway hyperresponsiveness, lung inflammation, and oxidative stress.

Edaravone attenuates experimental asthma in mice through induction of HO-1 and the Keap1/Nrf2 pathway.

Asthma is a chronic disease that threatens public health worldwide. Multiple studies have shown that oxidative stress plays an important role in the pathogenesis of asthma. Edaravone (Eda), a free radical scavenger, has been found to have a protective effect against lung injury due to its ability to eliminate reactive oxygen species. The present study aimed to investigate the effect of Eda on asthma and the mechanism underlying its actions. An experimental asthma model was induced in mice, before they were treated with different doses of Eda. Measurements of airway responsiveness to methacholine (Mch), cell counts and cytokine levels in bronchoalveolar lavage fluid (BALF) and of the oxidative products and antioxidant enzymes in lung tissue were taken in these asthma model mice and compared with control mice. Protein levels of kelch-like ECH-associated protein-1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1) were determined in the lung tissue of normal mice and Nrf2 and HO-1-deficient mice subject to the asthma model to investigate the mechanisms underlying Eda action. The results indicated that Eda effectively reduced airway responsiveness to Mch. The total number of cells and the numbers of eosinophils, lymphocytes and neutrophils in BALF of asthma model mice were also significantly reduced by Eda treatment when compared with normal saline treatment. Eda treatment significantly alleviated perivascular edema, peribronchial inflammation and macrophage infiltration in the alveolar space and decreased the levels of inflammatory cytokines released in BALF compared with control. Eda also significantly reduced the levels of oxidative stress markers in BALF and restored the levels of antioxidative enzyme, superoxide dismutase, when compared with control. The Keap1/Nrf2 ratio was significantly decreased with Eda compared with control due to an increase in Nrf2 and a decrease in Keap1 expression. HO-1 expression was increased by Eda. The airway responsiveness of Nrf2-/- mice or HO-1-/- mice to Mch was significantly higher compared with normal mice treated with Eda. Taken together, the results of the present study show that Eda exerts anti-inflammatory and antioxidative effects, which suggests a potential use for Eda in reduction of asthma severity. The activated Keap1/Nrf2 pathway and HO-1 may be involved in the anti-asthmatic effect of Eda.

Oxytocin maintains lung histological and functional integrity to confer protection in heat stroke

Oxytocin (OT) has been reported to have a protective effect in lipopolysaccharide-induced experimental acute lung injury (ALI). However, its role in heat stroke-related ALI has never been investigated. Herein, we aimed to explore the therapeutic effects and potential mechanism of action of OT on heat-induced ALI. Rats were treated with OT 60 min before the start of heat stress (42 °C for 80 min). Twenty minutes after the termination of heat stress, the effects of OT on lung histopathological changes, edema, acute pleurisy and the bronchoalveolar fluid levels of inflammatory cytokines and indicators of ischemia, cellular damage, and oxidative damage were assessed. We also evaluated the influence of OT pretreatment on heat-induced hypotension, hyperthermia, ALI score, and death in a rat model of heat stroke. The results showed that OT significantly reduced heat-induced lung edema, neutrophil infiltration, hemorrhage score, myeloperoxidase activity, ischemia, and the levels of inflammatory and oxidative damage markers in bronchoalveolar lavage fluid. The survival assessment confirmed the pathophysiological and biochemical results. An OT receptor antagonist (L-368,899) was administered 10 min before the OT injection to further demonstrate the role of OT in heat-induced ALI. The results showed that OT could not protect against the aforementioned heat stroke responses in rats treated with L-368,899. Interestingly, OT treatment 80 min after the start of heat shock did not affect survival. In conclusion, our data indicate that OT pretreatment can reduce the ischemic, inflammatory and oxidative responses related to heat-induced ALI in rats.

Grouping of carbonaceous nanomaterials based on association of patterns of inflammatory markers in BAL fluid with adverse outcomes in lungs

Carbonaceous nanomaterials (CNMs) are universally being used to make commodities, as they present unique opportunities for development and innovation in the fields of engineering, biotechnology, etc. As technology advances to incorporate CNMs in industry, the potential exposures associated with these particles also increase. CNMs have been found to be associated with substantial pulmonary toxicity, including inflammation, fibrosis, and/or granuloma formation in animal models. This study attempts to categorize the toxicity profiles of various carbon allotropes, in particular, carbon black, different multi-walled carbon nanotubes, graphene-based materials, and their derivatives. Statistical and machine learning-based approaches were used to identify groups of CNMs with similar pulmonary toxicity responses from a panel of proteins measured in bronchoalveolar lavage (BAL) fluid samples and with similar pathological outcomes in the lungs. Thus, grouped particles, based on their pulmonary toxicity profiles, were used to select a small set of proteins that could potentially identify and discriminate between the toxicity profiles associated within each group. Specifically, MDC/CCL22 and MIP-3β/CCL19 were identified as common protein markers associated with both toxicologically distinct groups of CNMs. In addition, the persistent expression of other selected protein markers in BAL fluid from each group suggested their ability to predict toxicity in the lungs, i.e. fibrosis and microgranuloma formation. The advantages of such approaches can have positive implications for further research in toxicity profiling.

Pathology and bronchoalveolar lavage fluid cellular and oxidative stress changes in canine pneumonia in Nigeria

Studies on canine respiratory diseases are scant in the literature especially in Africa, unlike the situation on ruminants. This study is on the pathology and bronchoalveolar cellular and oxidative stress changes in naturally occurring canine pneumonia in Nigeria. The dogs used were collected from cases submitted for necropsy in the institutional Department of Veterinary Pathology. Gross examination, bronchoalveolar lavage (BAL) cytology, oxidative biochemical assay of BAL fluid (BALf) supernatant and histology of sections from all the lung lobes were done using standard procedures. Grossly, 22 (31%) were normal while 48 (69%) were congested, haemorrhagic and/or pneumonic out of the 70 canine lungs examined. Microscopically, there were pulmonary congestion (4%), pulmonary oedema (20%), pulmonary haemorrhages (7%), atelectasis (4%), interstitial pneumonia (10%), bronchointerstitial pneumonia (14%) and bronchopneumonia (9%). The BALf cytology of pneumonic lungs showed increases in neutrophils, alveolar macrophages, lymphocytes and haemosiderophages including free and phagocytosed bacteria, and fungal hyphae. Glutathione peroxidase (GPx) and glutathione transferase (GST) activities increased in congested and bronchointerstitial pneumonic lungs but were reduced in other pneumonic lungs. The superoxide dismutase (SOD) activity was significantly reduced in the pneumonic canine lungs. Hydrogen peroxide generation increased in congestion and oedema, bronchopneumonia and bronchointerstitial pneumonia. Malondialdehyde (MDA) level increased in other congested and pneumonic lungs. There was also significant positive correlation of BALf pro-oxidant assay to the type and severity of pneumonia (+ 0.75, P < 0.05). Pneumonias account for 57.2% of the respiratory conditions of which bronchointerstitial and interstitial pneumonias are the prevalent types. The study also showed that oxidative stress markers in BALf may serve as predictors of pneumonia especially in the early stages. Since treatment recommendations for pneumonia often centre primarily on supportive care and anti-oxidant and antibiotic administration, further studies on causal agents, treatment and prevention strategies for canine pneumonia in Nigeria are warranted.