Adhesion molecules in subjects with COPD and healthy non-smokers: a cross sectional parallel group study

Exploring chemokines and soluble adhesion molecules in mustard lung pathogenesis

Sulfur mustard (SM), functioning as an alkylating agent, plays a significant role in developing respiratory system pathologies. This study aimed to evaluate serum concentrations of chemokines and soluble adhesion molecules in serious mustard lung (ML) patients 25-30 years after exposure to SM, exploring their roles in ML pathogenesis and disease severity. The study included 275 individuals exposed to SM and 64 unexposed individuals as controls. Serum samples were collected and clinical evaluations categorized disease severity and pulmonary pathogenesis. Serum levels of MCP-1/CCL2, RANTES/CCL5, CX3CL1, CXCL12s, P-selectin, sL-selectin, sE-selectin, sICAM-1 levels were measured using ELISA kits, and mRNA expression of CXCR4 in whole blood was determined via real-time PCR. Data analysis included comparisons between groups. SM-exposed individuals exhibited significantly higher MCP-1/CCL2 and RANTES/CCL5 levels, with decreased CX3CL1 levels compared to controls. CXCL12, selectins, sICAM-1 levels, and the expression level of CXCR4 showed no significant differences. Changes in some of the mentioned factors were observed, along with changes in the severity of the disease, suggesting potential roles in ML progression. The findings suggest a complex interplay of immune responses in ML pathogenesis, with elevated MCP-1/CCL2 and RANTES/CCL5 potentially contributing to inflammation, while decreased CX3CL1 levels and unchanged CXCL12 and CXCR4 may impair immune responses and tissue repair mechanisms. The unique chemokine and adhesion molecule profile observed in SM-exposed subgroups suggests ML as a differentiated pulmonary disease requiring further investigation into its pathogenesis and relationship with inflammatory disorders.

Comparing Adult Smokers Who Switched to JUUL versus Continuing Smokers: Biomarkers of Exposure and of Potential Harm and Respiratory Symptoms

OBJECTIVES

Real-world evidence on exposure to harmful and potentially harmful constituents (HPHCs) and on biological effects in cigarette smokers who switch to electronic nicotine delivery systems (ENDS) can inform the health effects of switching.

AIMS AND METHODS

This cross-sectional, observational study assessed adults who had smoked ≥10 cigarettes/day for ≥10 years, comparing 124 continuing cigarette smokers (Smokers) to 140 former smokers who switched to JUUL-brand ENDS exclusively for ≥6 months (Switchers). Assessments included biomarkers of exposure (BOEs) to select HPHCs, biomarkers of potential harm (BOPHs) related to smoking-related diseases, psychometric assessments of dependence on cigarettes and ENDS, respectively, and respiratory symptoms. Planned analyses compared geometric means, adjusted for demographic covariates; further analyses adjusted for additional lifestyle and smoking history covariates.

RESULTS

Nicotine levels were significantly higher in Switchers (median time switched = 3 years), who were unusually heavy users of JUUL. All other BOEs, including NNAL and HPMA3 (primary endpoints), were significantly lower in Switchers than Smokers. Most BOPHs (sICAM-1 [primary], and eg, white blood cell count, MCP1, HbA1c) were significantly lower in Switchers than Smokers; HDL was significantly higher. Switchers reported significantly lower dependence on JUUL than Smokers did on cigarettes, and respiratory symptom scores were significantly lower among Switchers than Smokers.

CONCLUSIONS

Compared to continuing smokers, smokers who switched to JUUL had substantially lower exposures to multiple HPHCs, favorable differences in markers of inflammation, endothelial function, oxidative stress, and cardiovascular risk, and fewer respiratory symptoms. These findings suggest that switching from cigarettes to JUUL likely reduces smokers' health risks.

IMPLICATIONS

Short-term confinement studies and randomized clinical trials demonstrate that adult smokers who switch completely to ENDS experience substantial reductions in exposure to many smoking-related toxicants. This study extends those findings to longer periods of switching to JUUL-brand ENDS (almost 3 years on average) under naturalistic use conditions in real-world settings and also found that switching to JUUL resulted in favorable differences in BOPHs more proximally related to smoking-induced disease, as well as in respiratory symptoms. Smokers who switch to ENDS reduce their exposure to toxicants, likely reducing their disease risk.

Serum levels of biomarkers that may link chronic obstructive pulmonary disease and depressive disorder

BACKGROUND

Depressive disorder is a common comorbidity of chronic obstructive pulmonary disease (COPD); according to some studies, it occurs in approximately 80% of patients. The presence of depressive symptoms influences the quality of life and affects the course and treatment of this disease. The cause of depressive symptoms in COPD and the linking mechanism between COPD and depressive disorder have not been clearly elucidated, and more studies are warranted. Inflammation and inflammation-related processes and biomarkers are involved in the etiology of COPD and depressive disorder and may be an explanation for the potential occurrence of depressive disorder in patients diagnosed with COPD. The scope of this study was to measure and compare the profiles of IL-18, TGF-β, RANTES, ICAM-1, and uPAR among stable COPD patients, recurrent depressive disorder (rDD) patients, and healthy controls.

METHODS

Inflammation and inflammation-related factors were evaluated in COPD patients, patients diagnosed with depressive disorder, and control individuals using enzyme-linked immunosorbent assays.

RESULTS

Interleukin (IL)-18, transforming growth factor (TGF)-β, chemokine RANTES, and urokinase plasminogen activator receptor (uPAR) concentrations were higher in patients suffering from COPD and depression than in control patients. Intercellular adhesive molecule (ICAM)-1 levels were significantly higher in COPD patients and lower in depressive disorder patients than in controls.

CONCLUSIONS

Higher levels of IL-18, TGF-β, RANTES, and uPAR in patients with COPD might indicate the presence of depressive disorder and suggest the need for further evaluation of the mental state of these patients.

Novel Anti-Inflammatory Approaches to COPD

Airway inflammation, driven by different types of inflammatory cells and mediators, plays a fundamental role in COPD and its progression. Neutrophils, eosinophils, macrophages, and CD4+ and CD8+ T lymphocytes are key players in this process, although the extent of their participation varies according to the patient's endotype. Anti-inflammatory medications may modify the natural history and progression of COPD. However, since airway inflammation in COPD is relatively resistant to corticosteroid therapy, innovative pharmacological anti-inflammatory approaches are required. The heterogeneity of inflammatory cells and mediators in annethe different COPD endo-phenotypes requires the development of specific pharmacologic agents. Indeed, over the past two decades, several mechanisms that influence the influx and/or activity of inflammatory cells in the airways and lung parenchyma have been identified. Several of these molecules have been tested in vitro models and in vivo in laboratory animals, but only a few have been studied in humans. Although early studies have not been encouraging, useful information emerged suggesting that some of these agents may need to be further tested in specific subgroups of patients, hopefully leading to a more personalized approach to treating COPD.

Targeting Neutrophil β2-Integrins: A Review of Relevant Resources, Tools, and Methods

Neutrophils are important innate immune cells that respond during inflammation and infection. These migratory cells utilize β₂-integrin cell surface receptors to move out of the vasculature into inflamed tissues and to perform various anti-inflammatory responses. Although critical for fighting off infection, neutrophil responses can also become dysregulated and contribute to disease pathophysiology. In order to limit neutrophil-mediated damage, investigators have focused on β₂-integrins as potential therapeutic targets, but so far these strategies have failed in clinical trials. As the field continues to move forward, a better understanding of β₂-integrin function and signaling will aid the design of future therapeutics. Here, we provide a detailed review of resources, tools, experimental methods, and in vivo models that have been and will continue to be utilized to investigate the vitally important cell surface receptors, neutrophil β₂-integrins.

Biomarker-based clustering of patients with chronic obstructive pulmonary disease

Rationale

COPD has been associated repeatedly with single biomarkers of systemic inflammation, ignoring the complexity of inflammatory pathways. This study aimed to cluster patients with COPD based on systemic markers of inflammatory processes and to evaluate differences in their clinical characterisation and examine how these differences may relate to altered biological pathways.

Methods

213 patients with moderate-to-severe COPD in a clinically stable state were recruited and clinically characterised, which included a venous blood sample for analysis of serum biomarkers. Patients were clustered based on the overall similarity in systemic levels of 57 different biomarkers. To determine interactions among the regulated biomarkers, protein networks and biological pathways were examined for each patient cluster.

Results

Four clusters were identified: two clusters with lower biomarker levels (I and II) and two clusters with higher biomarker levels (III and IV), with only a small number of biomarkers with similar trends in expression. Pathway analysis indicated that three of the four clusters were enriched in Rage (receptor for advanced glycation end-products) and Oncostatin M pathway components. Although the degree of airflow limitation was similar, the clinical characterisation of clusters ranged from 1) better functional capacity and health status and fewer comorbidities; 2) more underweight, osteoporosis and static hyperinflation; 3) more metabolically deranged; and 4) older subjects with worse functional capacity and higher comorbidity load.

Conclusions

These new insights may help to understand the functionally relevant inflammatory interactions in the pathophysiology of COPD as a heterogeneous disease.

Role of Short-Chain Fatty Acids Produced by Gut Microbiota in Innate Lung Immunity and Pathogenesis of the Heterogeneous Course of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a widespread socially significant disease. The development of COPD involves the innate immune system. Interestingly, the regulation of the innate lung immune system is related to the gut microbiota. This connection is due to the production by gut microorganisms of short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate. Nutritional disturbances and changes in the structure of the intestinal microbiota lead to a decrease in SCFAs production and their effect on pulmonary immunity. The presence of a metabolic and immune axis linking the lungs and gut plays an important role in the pathogenesis of COPD. In addition, the nature of nutrition and SCFAs may participate in the development of the clinically heterogeneous course of COPD.

Dysregulation of COVID-19 related gene expression in the COPD lung

BACKGROUND

Chronic obstructive pulmonary disease (COPD) patients are at increased risk of poor outcome from Coronavirus disease (COVID-19). Early data suggest elevated Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) receptor angiotensin converting enzyme 2 (ACE2) expression, but relationships to disease phenotype and downstream regulators of inflammation in the Renin-Angiotensin system (RAS) are unknown. We aimed to determine the relationship between RAS gene expression relevant to SARS-CoV-2 infection in the lung with disease characteristics in COPD, and the regulation of newly identified SARS-CoV-2 receptors and spike-cleaving proteases, important for SARS-CoV-2 infection.

METHODS

We quantified gene expression using RNA sequencing of epithelial brushings and bronchial biopsies from 31 COPD and 37 control subjects.

RESULTS

ACE2 gene expression (log2-fold change (FC)) was increased in COPD compared to ex-smoking (HV-ES) controls in epithelial brushings (0.25, p = 0.042) and bronchial biopsies (0.23, p = 0.050), and correlated with worse lung function (r = - 0.28, p = 0.0090). ACE2 was further increased in frequent exacerbators compared to infrequent exacerbators (0.51, p = 0.00045) and associated with use of ACE inhibitors (ACEi) (0.50, p = 0.0034), having cardiovascular disease (0.23, p = 0.048) or hypertension (0.34, p = 0.0089), and inhaled corticosteroid use in COPD subjects in bronchial biopsies (0.33, p = 0.049). Angiotensin II receptor type (AGTR)1 and 2 expression was decreased in COPD bronchial biopsies compared to HV-ES controls with log2FC of -0.26 (p = 0.033) and - 0.40, (p = 0.0010), respectively. However, the AGTR1:2 ratio was increased in COPD subjects compared with HV-ES controls, log2FC of 0.57 (p = 0.0051). Basigin, a newly identified potential SARS-CoV-2 receptor was also upregulated in both brushes, log2FC of 0.17 (p = 0.0040), and bronchial biopsies, (log2FC of 0.18 (p = 0.017), in COPD vs HV-ES. Transmembrane protease, serine (TMPRSS)2 was not differentially regulated between control and COPD. However, various other spike-cleaving proteases were, including TMPRSS4 and Cathepsin B, in both epithelial brushes (log2FC of 0.25 (p = 0.0012) and log2FC of 0.56 (p = 5.49E-06), respectively) and bronchial biopsies (log2FC of 0.49 (p = 0.00021) and log2FC of 0.246 (p = 0.028), respectively).

CONCLUSION

This study identifies key differences in expression of genes related to susceptibility and aetiology of COVID-19 within the COPD lung. Further studies to understand the impact on clinical course of disease are now required.

Chronic Obstructive Pulmonary Disease and the Cardiovascular System: Vascular Repair and Regeneration as a Therapeutic Target

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide and encompasses chronic bronchitis and emphysema. It has been shown that vascular wall remodeling and pulmonary hypertension (PH) can occur not only in patients with COPD but also in smokers with normal lung function, suggesting a causal role for vascular alterations in the development of emphysema. Mechanistically, abnormalities in the vasculature, such as inflammation, endothelial dysfunction, imbalances in cellular apoptosis/proliferation, and increased oxidative/nitrosative stress promote development of PH, cor pulmonale, and most probably pulmonary emphysema. Hypoxemia in the pulmonary chamber modulates the activation of key transcription factors and signaling cascades, which propagates inflammation and infiltration of neutrophils, resulting in vascular remodeling. Endothelial progenitor cells have angiogenesis capabilities, resulting in transdifferentiation of the smooth muscle cells via aberrant activation of several cytokines, growth factors, and chemokines. The vascular endothelium influences the balance between vaso-constriction and -dilation in the heart. Targeting key players affecting the vasculature might help in the development of new treatment strategies for both PH and COPD. The present review aims to summarize current knowledge about vascular alterations and production of reactive oxygen species in COPD. The present review emphasizes on the importance of the vasculature for the usually parenchyma-focused view of the pathobiology of COPD.

The Combination of Hemogram Indexes to Predict Exacerbation in Stable Chronic Obstructive Pulmonary Disease

Background: Chronic obstructive pulmonary disease (COPD) is characterized by pulmonary and systemic inflammatory processes, and exacerbation of COPD represents a critical moment in the progression of COPD. Several biomarkers of inflammation have been proposed to have a predictive function in acute exacerbation. However, their use is still limited in routine clinical practice. The purpose of our study is to explore the prognostic efficacy of novel inflammatory hemogram indexes in the exacerbation among stable COPD patients. Method: A total of 275 stable COPD patients from the Shanghai COPD Investigation Comorbidity Program were analyzed in our study. Blood examinations, especially ratio indexes like platelet-lymphocyte ratio (PLR), platelet × neutrophil/lymphocyte ratio [systemic immune-inflammation index (SII)], and monocyte × neutrophil/lymphocyte ratio [systemic inflammation response index (SIRI)], lung function test, CT scans, and questionnaires were performed at baseline and routine follow-ups. Clinical characteristics and information of exacerbations were collected every 6 months. The relationship between hemogram indexes and diverse degrees of exacerbation was assessed by logistic regression. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to evaluate the ability of hemogram indexes to predict exacerbation of COPD. Furthermore, the discrimination and accuracy of combined indexes were measured by ROC and calibration curve. Result: There was a significant positive correlation between PLR levels and total exacerbation of COPD patients in a stable stage in a year. Also, the predictive ability of PLR exceeded any other ratio indexes, with an AUC of 0.66. SII and SIRI ranked second only to PLR, with an AUC of 0.64. When combining PLR with other indexes (sex, COPD year, and St. George's Respiratory Questionnaire scores), they were considered as the most suitable panel of index to predict total exacerbation. Based on the result of the ROC curve and calibration curve, the combination shows optimal discrimination and accuracy to predict exacerbation events in COPD patients. Conclusion: The hemogram indexes PLR, SII, and SIRI were associated with COPD exacerbation. Moreover, the prediction capacity of exacerbation was significantly elevated after combining inflammatory hemogram index PLR with other indexes, which will make it a promisingly simple and effective marker to predict exacerbation in patients with stable COPD.

Progress in the mechanism and targeted drug therapy for COPD

Chronic obstructive pulmonary disease (COPD) is emphysema and/or chronic bronchitis characterised by long-term breathing problems and poor airflow. The prevalence of COPD has increased over the last decade and the drugs most commonly used to treat it, such as glucocorticoids and bronchodilators, have significant therapeutic effects; however, they also cause side effects, including infection and immunosuppression. Here we reviewed the pathogenesis and progression of COPD and elaborated on the effects and mechanisms of newly developed molecular targeted COPD therapeutic drugs. Among these new drugs, we focussed on thioredoxin (Trx). Trx effectively prevents the progression of COPD by regulating redox status and protease/anti-protease balance, blocking the NF-κB and MAPK signalling pathways, suppressing the activation and migration of inflammatory cells and the production of cytokines, inhibiting the synthesis and the activation of adhesion factors and growth factors, and controlling the cAMP-PKA and PI3K/Akt signalling pathways. The mechanism by which Trx affects COPD is different from glucocorticoid-based mechanisms which regulate the inflammatory reaction in association with suppressing immune responses. In addition, Trx also improves the insensitivity of COPD to steroids by inhibiting the production and internalisation of macrophage migration inhibitory factor (MIF). Taken together, these findings suggest that Trx may be the ideal drug for treating COPD.

Increased CD11b and Decreased CD62L in Blood and Airway Neutrophils from Long-Term Smokers with and without COPD

There is incomplete mechanistic understanding of the mobilization of neutrophils in the systemic and local compartment in smokers with chronic obstructive pulmonary disease (COPD). In this pilot study, we characterized how the adhesion molecules CD11b and CD62L, surface markers indicative of priming, are altered as neutrophils extravasate, and whether surface density of CD11b and CD62L differs between long-term tobacco smokers (LTS) with and without COPD compared with healthy never-smokers (HNS). Unstimulated blood neutrophils from LTS with (n = 5) and without (n = 9) COPD displayed lower surface density of CD62L compared with HNS (n = 8). In addition, surface density of CD11b was higher in bronchoalveolar lavage (BAL) neutrophils from LTS without COPD compared with those with COPD and HNS. Moreover, in BAL neutrophils from all study groups, CD62L was lower compared with matched blood neutrophils. In addition, BAL neutrophils responded with a further decrease in CD62L to ex vivo TNF stimulation. Thus, neutrophils in the airway lumen display a higher state of priming than systemic neutrophils and bear the potential to be further primed by local cytokines even with no smoking or the presence of COPD, findings that may represent a universal host defense mechanism against local bacteria. Moreover, systemic neutrophils are primed in LTS regardless of COPD. Further studies in larger materials are warranted to determine whether the priming of neutrophils is protective against COPD or merely preceding it.

Endothelial function and T-lymphocyte subsets in patients with overlap syndrome of chronic obstructive pulmonary disease and obstructive sleep apnea

BACKGROUND

The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) is termed overlap syndrome (OS). COPD and OSA both have increased risks of developing cardiovascular diseases. This study aimed to explore if patients with OS exhibited a higher prevalence of cardiovascular complications, and if patients with OS exhibited vascular endothelial dysfunction and abnormalities in the cellular immune function of T lymphocytes.

METHODS

Totally 25 patients with stable COPD (COPD group), 25 patients with OSA (OSA group), 25 patients with OS (OS group), and 20 healthy adults (control group) were enrolled between January 2017 and December 2017 from the Respiratory Department of Tianjin Medical University General Hospital. The clinical characteristics of the four groups were collected and the expression levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), tumor necrosis factor-α (TNF-α), and T-lymphocyte subsets were detected. One-way analysis of variance, χ test and Pearson correlation were used to manage the data.

RESULTS

The prevalence of hypertension and coronary heart disease was significantly higher in the OS group than in the control, OSA, and COPD groups (χ = 20.69, P < 0.05 and χ = 11.03, P < 0.05, respectively). The levels of sVCAM-1 and TNF-α were significantly higher in the OS group than in other groups (F = 127.40, P < 0.05 and F = 846.77, P < 0.05, respectively). The percentage of CD4+ lymphocytes and CD4+/CD8+ were both significantly lower in the OS group than in any other group (F = 25.40, P < 0.05 and F = 75.08, P < 0.05, respectively). There were significantly negative correlations in the levels of sVCAM-1 and TNF-α with CD4+/CD8+ lymphocytes (r = -0.77, P < 0.05 and r = -0.83, P < 0.05, respectively).

CONCLUSIONS

The prevalence of hypertension and coronary heart disease was higher in patients with OS than in patients with either OSA or COPD alone. Patients with OS exhibited more severe vascular endothelial injury, stronger inflammatory response, and lower cellular immune function.

Blood Neutrophils In COPD But Not Asthma Exhibit A Primed Phenotype With Downregulated CD62L Expression

Purpose

To characterize neutrophils in obstructive airway disease by measuring their surface adhesion molecules and oxidative burst along with characterizing them into different subsets as per their adhesion molecule expression.

Patients and methods

Peripheral blood from adults with COPD (n=17), asthma (n=20), and healthy participants (n=19) was examined for expression of CD16, CD62L, CD11b, CD11c, and CD54, and analyzed by flow cytometry. For oxidative burst and CD62L shedding analysis, CD16 and CD62L stained leukocytes were loaded with Dihydrorhodamine-123 (DHR-123) and stimulated with N-Formylmethionine-leucyl-phenylalanine (fMLF). Neutrophil subsets were characterized based on CD16 and CD62L expression. Marker surface expression was recorded on CD16⁺ neutrophils as median fluorescence intensity (MFI).

Results

Neutrophil surface expression of CD62L was significantly reduced in COPD (median (IQR) MFI: 1156 (904, 1365)) compared with asthma (1865 (1157, 2408)) and healthy controls (2079 (1054, 2960)); p=0.028. COPD neutrophils also demonstrated a significant reduction in CD62L expression with and without fMLF stimulation. Asthma participants had a significantly increased proportion and number of CD62L^bright/CD16^dim neutrophils (median: 5.4% and 0.14 × 10⁹/L, respectively), in comparison with healthy (3.54% and 0.12 × 10⁹/L, respectively); p<0.017.

Conclusion

Reduced CD62L expression suggests blood neutrophils have undergone priming in COPD but not in asthma, which may be the result of systemic inflammation. The increased shedding of CD62L receptor by COPD blood neutrophils suggests a high sensitivity for activation.

Centrilobular emphysema and coronary artery calcification: mediation analysis in the SPIROMICS cohort

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with a two-to-five fold increase in the risk of coronary artery disease independent of shared risk factors. This association is hypothesized to be mediated by systemic inflammation but this link has not been established.

METHODS

We included 300 participants enrolled in the SPIROMICS cohort, 75 each of lifetime non-smokers, smokers without airflow obstruction, mild-moderate COPD, and severe-very severe COPD. We quantified emphysema and airway disease on computed tomography, characterized visual emphysema subtypes (centrilobular and paraseptal) and airway disease, and used the Weston visual score to quantify coronary artery calcification (CAC). We used the Sobel test to determine whether markers of systemic inflammation mediated a link between spirometric and radiographic features of COPD and CAC.

RESULTS

FEV1/FVC but not quantitative emphysema or airway wall thickening was associated with CAC (p = 0.036), after adjustment for demographics, diabetes mellitus, hypertension, statin use, and CT scanner type. To explain this discordance, we examined visual subtypes of emphysema and airway disease, and found that centrilobular emphysema but not paraseptal emphysema or bronchial thickening was independently associated with CAC (p = 0.019). MMP3, VCAM1, CXCL5 and CXCL9 mediated 8, 8, 7 and 16% of the association between FEV1/FVC and CAC, respectively. Similar biomarkers partially mediated the association between centrilobular emphysema and CAC.

CONCLUSIONS

The association between airflow obstruction and coronary calcification is driven primarily by the centrilobular subtype of emphysema, and is linked through bioactive molecules implicated in the pathogenesis of atherosclerosis.

TRIAL REGISTRATION

ClinicalTrials.gov: Identifier: NCT01969344 .

Long-term smoking alters abundance of over half of the proteome in bronchoalveolar lavage cell in smokers with normal spirometry, with effects on molecular pathways associated with COPD

Background

Smoking represents a significant risk factor for many chronic inflammatory diseases, including chronic obstructive pulmonary disease (COPD).

Methods

To identify dysregulation of specific proteins and pathways in bronchoalveolar lavage (BAL) cells associated with smoking, isobaric tags for relative and absolute quantitation (iTRAQ)-based shotgun proteomics analyses were performed on BAL cells from healthy never-smokers and smokers with normal lung function from the Karolinska COSMIC cohort. Multivariate statistical modeling, multivariate correlations with clinical data, and pathway enrichment analysis were performed.

Results

Smoking exerted a significant impact on the BAL cell proteome, with more than 500 proteins representing 15 molecular pathways altered due to smoking. The majority of these alterations occurred in a gender-independent manner. The phagosomal- and leukocyte trans endothelial migration (LTM) pathways significantly correlated with FEV₁/FVC as well as the percentage of CD8⁺ T-cells and CD8⁺CD69⁺ T-cells in smokers. The correlations to clinical parameters in healthy never-smokers were minor.

Conclusion

The significant correlations of proteins in the phagosome- and LTM pathways with activated cytotoxic T-cells (CD69+) and the level of airway obstruction (FEV₁/FVC) in smokers, both hallmarks of COPD, suggests that these two pathways may play a role in the molecular events preceding the development of COPD in susceptible smokers. Both pathways were found to be further dysregulated in COPD patients from the same cohort, thereby providing further support to this hypothesis. Given that not all smokers develop COPD in spite of decades of smoking, it is also plausible that some of the molecular pathways associated with response to smoking exert protective mechanisms to smoking-related pathologies in resilient individuals.

Trial registration

ClinicalTrials.gov identifier NCT02627872; Retrospectively registered on December 9, 2015.

Electronic supplementary material

The online version of this article (10.1186/s12931-017-0695-6) contains supplementary material, which is available to authorized users.

Review of biomarkers to assess the effects of switching from cigarettes to modified risk tobacco products

Context: One approach to reducing the harm caused by cigarette smoking, at both individual and population level, is to develop, assess and commercialize modified risk alternatives that adult smokers can switch to. Studies to demonstrate the exposure and risk reduction potential of such products generally involve the measuring of biomarkers, of both exposure and effect, sampled in various biological matrices.Objective: In this review, we detail the pros and cons for using several biomarkers as indicators of effects of changing from conventional cigarettes to modified risk products.Materials and methods: English language publications between 2008 and 2017 were retrieved from PubMed using the same search criteria for each of the 25 assessed biomarkers. Nine exclusion criteria were applied to exclude non-relevant publications.Results: A total of 8876 articles were retrieved (of which 7476 were excluded according to the exclusion criteria). The literature indicates that not all assessed biomarkers return to baseline levels following smoking cessation during the study periods but that nine had potential for use in medium to long-term studies.Discussion and conclusion: In clinical studies, it is important to choose biomarkers that show the biological effect of cessation within the duration of the study.

The main rhinovirus respiratory tract adhesion site (ICAM-1) is upregulated in smokers and patients with chronic airflow limitation (CAL)

BACKGROUND

ICAM-1 is a major receptor for ~60% of human rhinoviruses, and non-typeable Haemophilus influenzae, two major pathogens in COPD. Increased cell-surface expression of ICAM-1 in response to tobacco smoke exposure has been suggested. We have investigated epithelial ICAM-1 expression in both the large and small airways, and lung parenchyma in smoking-related chronic airflow limitation (CAL) patients.

METHODS

We evaluated epithelial ICAM-1 expression in resected lung tissue: 8 smokers with normal spirometry (NLFS); 29 CAL patients (10 small-airway disease; 9 COPD-smokers; 10 COPD ex-smokers); Controls (NC): 15 normal airway/lung tissues. Immunostaining with anti-ICAM-1 monoclonal antibody was quantified with computerized image analysis. The percent and type of cells expressing ICAM-1 in large and small airway epithelium and parenchyma were enumerated, plus percentage of epithelial goblet and submucosal glands positive for ICAM- 1.

RESULTS

A major increase in ICAM-1 expression in epithelial cells was found in both large (p < 0.006) and small airways (p < 0.004) of CAL subjects compared to NC, with NLFS being intermediate. In the CAL group, both basal and luminal areas stained heavily for ICAM-1, so did goblet cells and sub-mucosal glands, however in either NC or NLFS subjects, only epithelial cell luminal surfaces stained. ICAM-1 expression on alveolar pneumocytes (mainly type II) was slightly increased in CAL and NLFS (p < 0.01). Pack-years of smoking correlated with ICAM-1 expression (r = 0.49; p < 0.03).

CONCLUSION

Airway ICAM-1 expression is markedly upregulated in CAL group, which could be crucial in rhinoviral and NTHi infections. The parenchymal ICAM-1 is affected by smoking, with no further enhancement in CAL subjects.

[Nebulized budesonide in the treatment of exacerbations of chronic obstructive pulmonary disease: Efficacy, safety, and effects on the serum levels of soluble differentiation molecules]

AIM

To investigate the efficacy and safety of nebulized budesonide and systemic glucocorticosteroids (GCS) (SGCS) in the treatment of an exacerbation of chronic obstructive pulmonary disease (COPD) and their effects on the serum concentration of soluble leukocyte differentiation antigens.

MATERIALS AND METHODS

Seventy-eight hospitalized patients with an acute exacerbation of COPD were randomized into two groups: 1) 37 patients took nebulized budesonide 4 mg/day; 2) 41 patients received intravenous prednisolone. The symptoms of COPD, forced expiratory volume in one second (FEV1) and other spirometric indicators, peripheral blood oxygen saturation (SpO2), and adverse events were studied. The serum levels of the soluble adhesion molecules CD50 (sCD50) and CD54 (sCD54) and the lymphocyte activation molecules CD38 (sCD38) and CD25 (sCD25) were investigated by an enzyme immunoassay.

RESULTS

There was a significant resolution of the symptoms of COPD, FEV1, and SpO2 in both groups after treatment. The incidence of hyperglycemia episodes was lower in the budesonide group than in the sGCS group. GCSs caused a decrease in the serum level of soluble interleukin-2 receptor (sCD25) in both groups. A prednisolone cycle, unlike a budesonide one, was found to reduce the concentrations of sCD54, sCD50, and sCD38.

CONCLUSION

Nebulized budesonide is an effective and safe alternative to SGCS in treating an exacerbation of COPD. Inhaled GCSs, unlike SGCSs, exhibit anti-inflammatory activity, but exert no immunosuppressive activity.

Electronic cigarette exposure triggers neutrophil inflammatory responses

Background

The use of electronic cigarettes (e-cigs) is increasing and there is widespread perception that e-cigs are safe. E-cigs contain harmful chemicals; more research is needed to evaluate the safety of e-cig use. Our aim was to investigate the effects of e-cigs on the inflammatory response of human neutrophils.

Methods

Neutrophils were exposed to e-cig vapour extract (ECVE) and the expression of CD11b and CD66b was measured by flow cytometry and MMP-9 and CXCL8 by ELISA. We also measured the activity of neutrophil elastase (NE) and MMP-9, along with the activation of inflammatory signalling pathways. Finally we analysed the biochemical composition of ECVE by ultra-high performance liquid chromatography mass spectrometry.

Results

ECVE caused an increase in the expression of CD11b and CD66b, and increased the release of MMP-9 and CXCL8. Furthermore, there was an increase in NE and MMP-9 activity and an increase in p38 MAPK activation. We also identified several harmful chemicals in ECVE, including known carcinogens.

Conclusions

ECVE causes a pro-inflammatory response from human neutrophils. This raises concerns over the safety of e-cig use.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-016-0368-x) contains supplementary material, which is available to authorized users.

[Morphometric characteristics of the bronchial tree in smokers with and without chronic obstructive pulmonary disease]

AIM

To reveal the tissue, cellular, and molecular predictors leading to the development of chronic obstructive pulmonary disease (COPD) in smokers on the basis of a morphometric analysis of bronchial biopsy specimens.

MATERIALS AND METHODS

A cross-sectional study was conducted in 115 smokers aged 40 to 60 years (58.3±3.24 years) with a male predominance of 90.9%. Morphological examination of bronchial biopsy specimens was first made in the smoking patients with and without COPD.

RESULTS

The smokers with COPD versus those without this condition were found to have a statistically significant increase in a number of indicators: the specific volume (SV) of the surface epithelium (p=0.017), SV of basal epitheliocytes (p=0.008), the height of the epithelium (p=0.001), and the thickness of the basal membrane (p=0.006) due to impaired regeneration processes in the bronchial epithelium and to fibrosis of the lamina propria of the bronchi with a concurrent increase in the total number of fibroblasts. The group of smokers with COPD, unlike the comparison group, showed signs of vascular remodeling and microcirculatory disorders as the increased connective tissue volumetric density of the lamina propria of the bronchi with predominant perivascular localization. This was followed by reductions in the relative volume of capillaries (p=0.016), in the SV of micropinocytic vesicles (p=0.005), and the size of Weibel-Palade bodies (p=0.004) in the endotheliocytes. In the COPD patients, the total density of cell infiltrate per mm2 of the lamina propria of the bronchi was statistically significantly (p<0.001) greater than that in the comparison group at the expense of neutrophils, lowly and moderately granulated basophils, macrophages, plasma cells with a simultaneous rise in their interepithelial forms.

CONCLUSION

Compensatory structural changes without signs of bronchial wall remodeling were recorded in the smokers without signs of bronchial disease. The smokers with the examined nosological entity were observed to have morphological signs of hemodynamic disorders, as well as perivascular fibrosis, atrophy, and squamous cell metaplasia of the bronchial epithelial lining.

Linoleic acid-derived lipid mediators increase in a female-dominated subphenotype of COPD

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality; however, the role of inflammatory mediators in its pathobiology remains unclear. The aim of this study was to investigate the influence of gender in COPD on lipid mediator levels.

Bronchoalveolar lavage fluid (BALF) and serum were obtained from healthy never-smokers, smokers and COPD patients (Global Initiative for Chronic Obstructive Lung Disease stage I–II/A–B) (n=114). 94 lipid mediators derived from the cytochrome-P450, lipoxygenase, and cyclooxygenase pathways were analysed by liquid chromatography-mass spectrometry.

Multivariate modelling identified a 9-lipid panel in BALF that classified female smokers with COPD from healthy female smokers (p=6×10−6). No differences were observed for the corresponding male population (p=1.0). These findings were replicated in an independent cohort with 92% accuracy (p=0.005). The strongest drivers were the cytochrome P450-derived epoxide products of linoleic acid (leukotoxins) and their corresponding soluble epoxide hydrolase (sEH)-derived products (leukotoxin-diols). These species correlated with lung function (r=0.87; p=0.0009) and mRNA levels of enzymes putatively involved in their biosynthesis (r=0.96; p=0.003). Leukotoxin levels correlated with goblet cell abundance (r=0.72; p=0.028).

These findings suggest a mechanism by which goblet cell-associated cytochrome-P450 and sEH activity produce elevated leukotoxin-diol levels, which play a putative role in the clinical manifestations of COPD in a female-dominated disease sub-phenotype.

Intercellular adhesion molecule 1 and progression of percent emphysema: the MESA Lung Study

BACKGROUND

Endothelial intercellular adhesion molecule (ICAM) 1 binds neutrophils and facilitates their transmigration into the lung; E-selectin facilitates leukocyte rolling. As neutrophils contribute to tissue destruction in emphysema and chronic obstructive pulmonary disease, we hypothesized that soluble ICAM-1 (sICAM-1) and E-selectin (sE-selectin) would be associated with longitudinal progression of emphysema and lung function decline.

METHODS

The Multi-Ethnic Study of Atherosclerosis (MESA) enrolled participants 45-84 years old without clinical cardiovascular disease in 2000-02. The MESA Lung Study assessed percent emphysema (<-950 Hounsfield units) on cardiac (2000-07) and full-lung CT scans (2010-12), and spirometry was assessed twice over five years. sICAM-1 and sE-selectin were measured at baseline. Mixed-effect models adjusted for demographics, anthropometry, smoking, C-reactive protein, sphingomyelin and scanner factors.

RESULTS

Among 1865 MESA Lung participants with measurement of sICAM-1 and percent emphysema the mean log-sICAM-1 was 5.5 ± 0.3 ng/mL and percent emphysema increased 0.73 percentage points (95% CI: 0.34, 1.12; P < 0.001) over ten years. A one SD increase in sICAM-1 was associated with an accelerated increase in percent emphysema of 0.23 percentage points over ten years (95% CI: 0.06, 0.39; P = 0.007). No significant association was found for sE-selectin, or between any adhesion molecule and lung function.

CONCLUSIONS

Higher levels of sICAM-1 were independently associated with progression of percent emphysema in a general population sample.