Expression of interleukin (IL)-10, IL-17A and IL-22 in serum and sputum of stable chronic obstructive pulmonary disease patients

Dendritic Cells Promote the Differentiation of ILCs into NCR-ILC3s in the Lungs of Mice Exposed to Cigarette Smoke

The involvement of Group 3 innate lymphoid cells (ILC3s) and dendritic cells (DCs) in chronic lung inflammation has been increasingly regarded as the key to understand the inflammatory mechanisms of smoke-related chronic obstructive pulmonary disease (COPD). However, the mechanism underlying the engagement of both remains unclear. Our study aimed to explore NCR-ILC3 differentiation in the lungs of mice exposed to cigarette smoke (CS) and to further investigate whether DCs activated by CS exposure contribute to the differentiation of ILCs into NCR-ILC3s. The study involved both in vivo and in vitro experiments. In the former, the frequencies of lung NCR-ILC3s and NKp46-IL-17A+ ILCs and the expression of DCs, CD40, CD86, IL-23, and IL-1β quantified by flow cytometry were compared between CS-exposed mice and air-exposed mice. In the latter, NKp46-IL-17A+ ILC frequencies quantified by flow cytometry were compared after two cocultures, one involving lung CD45+Lin-CD127+ ILCs sorted from air-exposed mice and DCs sifted by CD11c magnetic beads from CS-exposed mice and another including identical CD45+Lin-CD127+ ILCs and DCs from air-exposed mice. The results indicated significant increases in the frequencies of NCR-ILC3s and NKp46-IL-17A+ ILCs; in the expression of DCs, CD40, CD86, IL-23, and IL-1β in CS-exposed mice; and in the frequency of NKp46-IL-17A+ ILCs after the coculture with DCs from CS-exposed mice. In conclusion, CS exposure increases the frequency of lung ILCs and NCR-ILC3s. CS-induced DC activation enhances the differentiation of ILCs into NCR-ILC3s, which likely acts as a mediating step in the involvement of NCR-ILC3s in chronic lung inflammation.

Phenotypes of regulatory T cells in different stages of COPD

BACKGROUND

Previous studies have shown that failure to control inflammatory processes mediated by regulatory T (Treg) cells contributes to chronic obstructive pulmonary disease (COPD) development and progression. The activity of Treg cells depends on their phenotypic characteristics: resting Treg (rTreg, CD3+CD4+CD25+FOXP3+CD25++CD45RA+) and activated Treg (aTreg, CD3+CD4+CD25+FOXP3+CD25+++CD45RA-) cells exhibit immunosuppressive activity, while cytokine-secreting T cells (FrIII, CD3+CD4+CD25+FOXP3+CD25++CD45RA-) exhibit proinflammatory activity. Previous findings have shown an increased density of cytokine-secreting T cells in COPD patients experiencing exacerbation. However, the methods for evaluating COPD under stable conditions are lacking.

AIM

To evaluate Treg cell phenotypes in patients with different stages of COPD under stable conditions.

METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from non-obstructed smokers and ex-smokers (NOS group, n = 19) and COPD patients at different stages (COPD I-II group, n = 25; COPD III-IV group, n = 25). The phenotypic characteristics of Treg cells and Th17 cells and their respective intracellular cytokines were analyzed by flow cytometry.

RESULTS

Both obstructed groups showed an increase in the proportion of rTregs, while the COPD III-IV group showed additional increases in total Treg and Th17 cells and in IL-10+ cells. There was an increase in proinflammatory mediators (CD3+CD4+IL-17+ cells; CD3+CD4+RORγt+ cells) in the COPD I-II group. In contrast, the NOS group demonstrated high proportions of proinflammatory Treg cells and proinflammatory CD8+ T cells (CD3+CD8+IL-17+).

CONCLUSION

Despite the increase in both total Treg cells and the rTreg phenotype from the early stages of COPD, there was a decrease in cells expressing IL-10, suggesting a failure in controlling the inflammatory process. These events precede the progression of the inflammatory process mediated by Th17 cells.

New markers in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), a global healthcare and socioeconomic burden, is a multifaceted respiratory disorder that results in substantial decline in health status and life quality. Acute exacerbations of the disease contribute significantly to increased morbidity and mortality. Consequently, the identification of reliable and effective biomarkers for rapid diagnosis, prediction, and prognosis of exacerbations is imperative. In addition, biomarkers play a crucial role in monitoring responses to therapeutic interventions and exploring innovative treatment strategies. Although established markers such as CRP, fibrinogen and neutrophil count are routinely used, a universal marker is lacking. Fortunately, an increasing number of studies based on next generation analytics have explored potential biomarkers in COPD. Here we review those advances and the need for standardized validation studies in the appropriate clinical setting.

The imbalance of pulmonary Th17/Treg cells in BALB/c suckling mice infected with respiratory syncytial virus-mediated intestinal immune damage and gut microbiota changes

The immune response induced by respiratory syncytial virus (RSV) infection is closely related to changes in the composition and function of gastrointestinal microorganisms. However, the specific mechanism remains unknown and the pulmonary-intestinal axis deserves further study. In this study, the mRNA levels of ROR-γt and Foxp3 in the lung and intestine increased first and then decreased. IL-17 and IL-22 reached the maximum on the third day after infection in the lung, and on the second day after infection in the small intestine and colon, respectively. RegⅢγ in intestinal tissue reached the maximum on the third day after RSV infection. Moreover, the genus enriched in the RSV group was Aggregatibacter, and Proteus was reduced. RSV infection not only causes Th17/Treg cell imbalance in the lungs of mice but also leads to the release of excessive IL-22 from the lungs through blood circulation which binds to IL-22 receptors on the intestinal surface, inducing RegⅢγ overexpression, impaired intestinal Th17/Treg development, and altered gut microbiota composition. Our research reveals a significant link between the pulmonary and intestinal axis after RSV infection.

IMPORTANCE

RSV is the most common pathogen causing acute lower respiratory tract infections in infants and young children, but the complex interactions between the immune system and gut microbiota induced by RSV infection still requires further research. In this study, it was suggested that RSV infection in 7-day-old BALB/c suckling mice caused lung inflammation and disruption of Th17/Treg cells development, and altered the composition of gut microbiota through IL-22 induced overexpression of RegⅢγ, leading to intestinal immune injury and disruption of gut microbiota. This research reveals that IL-22 may be the link between the lung and gut. This study may provide a new insight into the intestinal symptoms caused by RSV and other respiratory viruses and the connection between the lung and gut axis, as well as new therapeutic ideas for the treatment of RSV-infected children.

Systemic Manifestations of COPD and the Impact of Dual Bronchodilation with Tiotropium/Olodaterol on Cardiac Function and Autonomic Integrity

Background: Chronic obstructive pulmonary disease (COPD) has significant systemic manifestations, including cardiovascular morbidity. The main aim of our study was to evaluate the effect of short-term COPD treatment with tiotropium/olodaterol (TIO/OLO) 5/5 μg on cardiac function and autonomic integrity. Methods: Twenty-nine patients with newly diagnosed moderate-to-severe COPD were enrolled. We performed pulmonary function tests, cardiac magnetic resonance, cardiac 123I-metaiodobenzylguanidine (123I-MIBG) imaging and analysis of blood biomarkers on our study subjects. The correlations between the tests' results were evaluated at baseline. The changes in pulmonary and cardiac parameters from baseline through 12 weeks were assessed. Results: Significant associations between pulmonary function tests' results and high-sensitivity C-reactive protein (hs-CRP), as well as interleukin-22 (IL-22), were observed at baseline. Treatment with TIO/OLO significantly improved lung function as measured by spirometry and body plethysmography. Moreover, we found that the cardiac index increased from 2.89 (interquartile range (IQR) 1.09) to 3.21 L/min/m2 (IQR 0.78) (p = 0.013; N = 18) and the late heart-to-mediastinum ratio improved from 1.88 (IQR 0.37) to 2 (IQR 0.41) (p = 0.026; N = 16) after 12 weeks of treatment. Conclusions: Treatment with TIO/OLO improves lung function and positively impacts cardiac function and autonomic integrity, suggesting that dual bronchodilation might have a potential in decreasing the risk for cardiac events in COPD. Hs-CRP and IL-22 might be beneficial in determining the intensity of systemic inflammation in COPD. Further research with a larger cohort is needed to enhance the initial results of this study.

Association Between IL-17 and Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Background

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease characterized by neutrophils airway infiltration. It is currently known that Interleukin-17 (IL-17) is an important pro-inflammatory factor. It can promote the accumulation of neutrophils and participate in the chronic inflammatory process of COPD. However, the value of IL-17 levels in the diagnosis and assessment of COPD remains controversial. In view of this, we conducted a systematic review and meta-analysis to assess its relevance.

Methods

We searched databases such as PubMed, Web of Science, Cochrane Library and Embase to extract original research.

Results

A total of 10 studies with 2268 participants were included in this meta-analysis. The results showed that the level of serum IL-17 in patients with stable COPD was significantly higher than that in healthy controls (standard mean difference SMD, 1.59, 95% CI 0.84-2.34; p<0.001). Compared with the stable COPD group, the serum IL-17 level in acute exacerbation (AECOPD) was significantly higher (SMD, 1.78, 95% CI 1.22-2.33; p<0.001). The level of IL-17 in sputum of COPD patients was also higher than that of healthy controls (SMD, 2.03, 95% CI 0.74-3.31; p<0.001).

Conclusion

Our results showed that IL-17 levels were elevated in serum and sputum in COPD patients compared with healthy controls, and IL-17 levels increased with disease progression. IL-17 serves as a potential biomarker to indicate the persistence of neutrophilic inflammation and exacerbation of COPD.

The Airway Microbiome-IL-17 Axis: a Critical Regulator of Chronic Inflammatory Disease

The respiratory tract is home to a diverse microbial community whose influence on local and systemic immune responses is only beginning to be appreciated. Increasing reports have linked changes in this microbiome to a range of pulmonary and extrapulmonary disorders, including asthma, chronic obstructive pulmonary disease and rheumatoid arthritis. Central to many of these findings is the role of IL-17-type immunity as an important driver of inflammation. Despite the crucial role played by IL-17-mediated immune responses in protection against infection, overt Th17 cell responses have been implicated in the pathogenesis of several chronic inflammatory diseases. However, our knowledge of the influence of bacteria that commonly colonise the respiratory tract on IL-17-driven inflammatory responses remains sparse. In this article, we review the current knowledge on the role of specific members of the airway microbiota in the modulation of IL-17-type immunity and discuss how this line of research may support the testing of susceptible individuals and targeting of inflammation at its earliest stages in the hope of preventing the development of chronic disease.

Th17/Treg Imbalance: Implications in Lung Inflammatory Diseases

Regulatory T cells (Tregs) and T helper 17 cells (Th17) are two CD4⁺ T cell subsets with antagonist effects. Th17 cells promote inflammation, whereas Tregs are crucial in maintaining immune homeostasis. Recent studies suggest that Th17 cells and Treg cells are the foremost players in several inflammatory diseases. In this review, we explore the present knowledge on the role of Th17 cells and Treg cells, focusing on lung inflammatory diseases, such as chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), sarcoidosis, asthma, and pulmonary infectious diseases.

Mechanisms Contributing to the Comorbidity of COPD and Lung Cancer

Lung cancer and chronic obstructive pulmonary disease (COPD) often co-occur, and individuals with COPD are at a higher risk of developing lung cancer. While the underlying mechanism for this risk is not well understood, its major contributing factors have been proposed to include genomic, immune, and microenvironment dysregulation. Here, we review the evidence and significant studies that explore the mechanisms underlying the heightened lung cancer risk in people with COPD. Genetic and epigenetic changes, as well as the aberrant expression of non-coding RNAs, predispose the lung epithelium to carcinogenesis by altering the expression of cancer- and immune-related genes. Oxidative stress generated by tobacco smoking plays a role in reducing genomic integrity, promoting epithelial-mesenchymal-transition, and generating a chronic inflammatory environment. This leads to abnormal immune responses that promote cancer development, though not all smokers develop lung cancer. Sex differences in the metabolism of tobacco smoke predispose females to developing COPD and accumulating damage from oxidative stress that poses a risk for the development of lung cancer. Dysregulation of the lung microenvironment and microbiome contributes to chronic inflammation, which is observed in COPD and known to facilitate cancer initiation in various tumor types. Further, there is a need to better characterize and identify the proportion of individuals with COPD who are at a high risk for developing lung cancer. We evaluate possible novel and individualized screening strategies, including biomarkers identified in genetic studies and exhaled breath condensate analysis. We also discuss the use of corticosteroids and statins as chemopreventive agents to prevent lung cancer. It is crucial that we optimize the current methods for the early detection and management of lung cancer and COPD in order to improve the health outcomes for a large affected population.

Caveolin-1 Promotes the Imbalance of Th17/Treg in Chronic Obstructive Pulmonary Disease by Regulating Hsp70 Expression

Objective

To investigate whether the expression of Hsp70 is associated with Cav-1 in promoting the imbalance of Th17/Treg cells in COPD.

Methods

The plasma Cav-1, Hsp70 expression were quantified by enzyme-linked immunosorbent assay (ELISA). The frequencies of circulating Th17, Treg cells and Th17/Treg ratio were determined by flow cytometry. Peripheral blood mononuclear cells (PBMCs) from subjects were transfected with Cav-1 or control plasmids and Hsp70 plasmid.

Results

We found that Cav-1 expression was lower but the levels of Hsp70 and Th17 cells were higher in COPD than in healthy control (HC). Hsp70 expressions were positively correlated with Cav-1 levels, Th17 cells, and Th17/Treg ratio in COPD but not in HC. Cav-1 over-expression resulted in an increase in Hsp70 and Th17 levels. Suppressing Hsp70 expressing by small interfering RNA (siRNA), the decline of Th17 frequency was observed in Cav-1-overexpressed PBMCs.

Conclusion

Collectively, our results illuminate that Cav-1 contributes to the imbalance of Th17/Treg through potentially regulating Hsp70 expression.

YPL-001 Shows Various Beneficial Effects against Cigarette Smoke Extract-Induced Emphysema Formation: Anti-Inflammatory, Anti-Oxidative, and Anti-Apoptotic Effects

Inflammation, oxidative stress, and apoptosis are thought to be important causes of chronic obstructive pulmonary disease (COPD). We investigated the effect of YPL-001 (under phase 2a study, ClinicalTrials.gov identifier NCT02272634), a drug derived from Pseudolysimachion rotundum var. subintegrum, on cigarette smoke extract (CSE)-induced inflammation, the anti-oxidative pathway, and apoptosis in human lung epithelial cells and on CSE-induced emphysema in mice. YPL-001 suppressed CSE-induced expression of IL8 mRNA and protein. This was due to the reduction in NF-κB transcriptional activity by YPL-001, which resulted from the blockade of acetylation of the NF-κB subunit p65 (Lys310). Histone deacetylases (HDACs) prevent gene transcription by condensing the DNA structure and affecting NF-κB nuclear binding. YPL-001 alone increased HDAC2 activity and enhanced CSE-induced activation of HDAC2. YPL-001-induced suppression of NF-κB transcriptional activity might be caused by increased HDAC2 activity. YPL-001 increased nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression via both degradation of its inhibitory protein, Kelch-like ECH-associated protein 1, and an increase in de novo protein synthesis. YPL-001 increased the DNA binding activity of Nrf2. Consequently, YPL-001 upregulated the expression of Nrf2-targeted anti-oxidant genes such as NAD(P)H quinone dehydrogenase 1 and heme oxygenase 1. Moreover, YPL-001 significantly suppressed CSE-induced apoptotic cell death. In vivo study showed that CSE-induced emphysematous changes, neutrophilic inflammation, protein leakage into bronchoalveolar space, and lung cell apoptosis in mice were suppressed by YPL-001 treatment. Taken together, these results suggest that YPL-001 is a good therapeutic candidate for the treatment of COPD by blocking inflammation and apoptosis and activating the anti-oxidative pathway.

IL-17 Cytokines and Chronic Lung Diseases

IL-17 cytokines are expressed by numerous cells (e.g., gamma delta (γδ) T, innate lymphoid (ILC), Th17, epithelial cells). They contribute to the elimination of bacteria through the induction of cytokines and chemokines which mediate the recruitment of inflammatory cells to the site of infection. However, IL-17-driven inflammation also likely promotes the progression of chronic lung diseases, such as chronic obstructive pulmonary disease (COPD), lung cancer, cystic fibrosis, and asthma. In this review, we highlight the role of IL-17 cytokines in chronic lung diseases.

The role of Th17 cells: explanation of relationship between periodontitis and COPD?

Periodontitis and chronic obstructive pulmonary disease (COPD) are chronic inflammatory diseases with common risk factors, such as long-term smoking, age, and social deprivation. Many observational studies have shown that periodontitis and COPD are correlated. Moreover, they share a common pathophysiological process involving local accumulation of inflammatory cells and cytokines and damage of soft tissues. The T helper 17 (Th17) cells and the related cytokines, interleukin (IL)-17, IL-22, IL-1β, IL-6, IL-23, and transforming growth factor (TGF)-β, play a crucial regulatory role during the pathophysiological process. This paper reviewed the essential roles of Th17 lineage in the occurrence of periodontitis and COPD. The gaps in the study of their common pathological mechanism were also evaluated to explore future research directions. Therefore, this review can provide study direction for the association between periodontitis and COPD and new ideas for the clinical diagnosis and treatment of the two diseases.

Immunophenotype in acute exacerbation of chronic obstructive pulmonary disease: a cross-sectional study

Background

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease, and the immune inflammatory response is thought to play an important role in pathogenesis. However, the immunophenotype of patients with COPD is unknown. Herein, we evaluated the immunophenotype of patients with acute exacerbation of COPD (AECOPD).

Methods

A cross-sectional study was conducted in West China Hospital from September 2018 to October 2019. The proportion of CD4 + T lymphocyte subtypes (Th1, Th2, Th17 and Treg) and levels of serum cytokines in the peripheral blood of patients with AECOPD, stable COPD (SCOPD), healthy smokers (HSs)and healthy controls (HCs) were evaluated.

Results

A total of 15 HCs, 19 HSs, 42 patients with SCOPD, and 55 patients with AECOPD were included. Compared to patients with SCOPD, Th1 cells, Th17 cells, Treg cell ratio, Th1/Th2 cell ratio, and the levels of C-reactive protein, interleukin (IL)-6, and IL-10 were significantly increased in patients with AECOPD (P < 0.001), while the proportion of Th2 cells was significantly reduced (P < 0.01). The proportion of Th17 cells was positively correlated with COPD Assessment Test score (r = 0.266, P = 0.009), modified Medical Research Council dyspnea score (r = 0.858, P < 0.0001), and Th1 cell ratio (r = 0.403, P < 0.0001) and negatively correlated with forced vital capacity (r = − 0.367, P = 0.009) and proportion of Th2 cells (r = − 0.655, P < 0.0001).

Conclusions

The immunophenotype of patients with AECOPD shows abnormal activation of Th1, Th17, and Treg cells. There is a correlation between the proportion of Th17 cells and the severity of COPD; therefore, this may represent a novel index for the evaluation of COPD severity.

Trial registration: China Clinical Trials Registry, ChiCTR1800018452, registered 19 September 2018, https://www.chictr.org.cn/index.aspx.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02058-x.

An inhibitor of RORγ for chronic pulmonary obstructive disease treatment

The role of RORγ as a transcription factor for Th17 cell differentiation and thereby regulation of IL-17 levels is well known. Increased RORγ expression along with IL-17A levels was observed in animal models, immune cells and BAL fluid of COPD patients. Increased IL-17A levels in severe COPD patients are positively correlated with decreased lung functions and increased severity symptoms and emphysema, supporting an urgency to develop novel therapies modulating IL-17 or RORγ for COPD treatment. We identified a potent RORγ inhibitor, PCCR-1 using hit to lead identification followed by extensive lead optimization by structure–activity relationship. PCCR-1 resulted in RORγ inhibition with a high degree of specificity in a biochemical assay, with > 300-fold selectivity over other isoforms of ROR. Our data suggest promising potency for IL-17A inhibition in human and canine PBMCs and mouse splenocytes with no significant impact on Th1 and Th2 cytokines. In vivo, PCCR-1 exhibited significant efficacy in the acute CS model with dose-dependent inhibition of the PD biomarkers that correlated well with the drug concentration in lung and BAL fluid, demonstrating an acceptable safety profile. This inhibitor effectively inhibited IL-17A release in whole blood and BALf samples from COPD patients. Overall, we identified a selective inhibitor of RORγ to pursue further development of novel scaffolds for COPD treatment.

Role of air pollutants in airway epithelial barrier dysfunction in asthma and COPD

Chronic exposure to environmental pollutants is a major contributor to the development and progression of obstructive airway diseases, including asthma and COPD. Understanding the mechanisms underlying the development of obstructive lung diseases upon exposure to inhaled pollutants will lead to novel insights into the pathogenesis, prevention and treatment of these diseases. The respiratory epithelial lining forms a robust physicochemical barrier protecting the body from inhaled toxic particles and pathogens. Inhalation of airborne particles and gases may impair airway epithelial barrier function and subsequently lead to exaggerated inflammatory responses and airway remodelling, which are key features of asthma and COPD. In addition, air pollutant-induced airway epithelial barrier dysfunction may increase susceptibility to respiratory infections, thereby increasing the risk of exacerbations and thus triggering further inflammation. In this review, we discuss the molecular and immunological mechanisms involved in physical barrier disruption induced by major airborne pollutants and outline their implications in the pathogenesis of asthma and COPD. We further discuss the link between these pollutants and changes in the lung microbiome as a potential factor for aggravating airway diseases. Understanding these mechanisms may lead to identification of novel targets for therapeutic intervention to restore airway epithelial integrity in asthma and COPD.

Exposure to air pollution induces airway epithelial barrier dysfunction through several mechanisms including increased oxidative stress, exaggerated cytokine responses and impaired host defence, which contributes to development of asthma and COPD. https://bit.ly/3DHL1CA

Chronic Inflammation as the Underlying Mechanism of the Development of Lung Diseases in Psoriasis: A Systematic Review

Psoriasis is a systemic inflammatory disease caused by dysfunctional interactions between the innate and adaptive immune responses. The systemic inflammation in psoriasis may be associated with the development of comorbidities, including lung diseases. In this review, we aimed to provide a summary of the evidence regarding the prevalence of lung diseases in patients with psoriasis and the potential underlying mechanisms. Twenty-three articles published between March 2010 and June 2021 were selected from 195 initially identified records. The findings are discussed in terms of the prevalence of asthma, chronic obstructive pulmonary disease, interstitial lung disease, obstructive sleep apnea, pulmonary hypertension, and sarcoidosis in psoriasis. A higher prevalence of lung diseases in psoriasis has been confirmed in asthma, chronic obstructive pulmonary disease, obstructive sleep apnea, and pulmonary hypertension. These conditions are important as they are previously unrecognized causes of morbidity and mortality in psoriasis. The development of lung diseases in patients with psoriasis can be explained by several mechanisms, including common risk factors, shared immune and molecular characteristics associated with chronic inflammation, as well as other mechanisms. Understanding the prevalence of lung diseases in psoriasis and their underlying mechanisms can help implement appropriate preventative and therapeutic strategies to address respiratory diseases in patients with psoriasis.

Th17/Treg Imbalance in Chronic Obstructive Pulmonary Disease: Clinical and Experimental Evidence

The imbalance between pro- and anti-inflammatory immune responses mediated by Th17 and Treg cells is deeply involved in the development and progression of inflammation in chronic obstructive pulmonary disease (COPD). Several clinical and experimental studies have described the Th17/Treg imbalance in COPD progression. Due to its importance, many studies have also evaluated the effect of different treatments targeting Th17/Treg cells. However, discrepant results have been observed among different lung compartments, different COPD stages or local and systemic markers. Thus, the data must be carefully examined. In this context, this review explores and summarizes the recent outcomes of Th17/Treg imbalance in COPD development and progression in clinical, experimental and in vitro studies.

Th17/Treg-Related Intracellular Signaling in Patients with Chronic Obstructive Pulmonary Disease: Comparison between Local and Systemic Responses

Th17/Treg imbalance plays a pivotal role in COPD development and progression. We aimed to assess Th17/Treg-related intracellular signaling at different COPD stages in local and systemic responses. Lung tissue and/or peripheral blood samples were collected and divided into non-obstructed (NOS), COPD stages I and II, and COPD stages III and IV groups. Gene expression of STAT3 and -5, RORγt, Foxp3, interleukin (IL)-6, -17, -10, and TGF-β was assessed by RT-qPCR. IL-6, -17, -10, and TGF-β levels were determined by ELISA. We observed increased STAT3, RORγt, Foxp3, IL-6, and TGF-β gene expression and IL-6 levels in the lungs of COPD I and II patients compared to those of NOS patients. Regarding the systemic response, we observed increased STAT3, RORγt, IL-6, and TGF-β gene expression in the COPD III and IV group and increased IL-6 levels in the COPD I and II group. STAT5 was increased in COPD III and IV patients, although there was a decrease in Foxp3 expression and IL-10 levels in the COPD I and II and COPD III and IV groups, respectively. We demonstrated that an increase in Th17 intracellular signaling in the lungs precedes this increase in the systemic response, whereas Treg intracellular signaling varies between the compartments analyzed in different COPD stages.

A qualitative and quantitative comparison of Crocus sativus and Nigella sativa immunomodulatory effects

The present article reviews and compares the immunomodulatory activities of Crocus sativus (C. sativus) and Nigella sativa (N. sativa) and their main bioactive compounds. Immunomodulatory effects of these plants, especially with respect to Th1 and Th2 cytokines, are discussed based on relevant articles, books, and conference papers published in English until the end of April 2020, that were retrieved from Web of Science, PubMed, Scopus and Google Scholar databases. C. sativus and its constituents increase immunoglobulin (Ig-)G, interleukin 2 (IL)-2, interferon gamma (IFN-γ), and IFN-γ/IL-4 ratio, but decreased IgM, IL-10 and IL-4 secretion. N. sativa extract and thymoquinone reduce the levels of IL-2, -4, -10, and -12, while enhance IFN-γ and serum IgG1 and 2a. The reviewed articles indicate that C. sativus and N. sativa and their constituents could be potentially considered promising treatments for disorders associated with immune-dysregulation such as asthma and cancer.

Long-term tobacco exposure and immunosenescence: Paradoxical effects on T-cells telomere length and telomerase activity

Immunosenescence are alterations on immune system that occurs throughout an individual life. The main characteristic of this process is replicative senescence, evaluated by telomere shortening. Several factors implicate on telomere shortening, such as smoking. In this study, we evaluated the influence of smoking and Chronic Obstructive Pulmonary Disease (COPD) on cytokines, telomere length and telomerase activity. Blood samples were collected from subjects aged over 60 years old: Healthy (never smokers), Smokers (smoking for over 30 years) and COPDs (ex-smokers for ≥15 years). A young group was included as control. PBMCs were cultured for assessment of telomerase activity using RT-PCR, and cytokines secretion flow cytometry. CD4+ and CD8+ purified lymphocytes were used to assess telomere length using FlowFISH. We observed that COPD patients have accelerated telomere shortening. Paradoxically, smokers without lung damage showed preserved telomere length, suggesting that tobacco smoking may affect regulatory mechanisms, such as telomerase. Telomerase activity showed diminished activity in COPDs, while Smokers showed increased activity compared to COPDs and Healthy groups. Extracellular environment reflected this unbalance, indicated by an anti-inflammatory profile in Smokers, while COPDs showed an inflammatory prone profile. Further studies focusing on telomeric maintenance may unveil mechanisms that are associated with cancer under long-term smoking.

IL-17-Mediated Inflammation Promotes Cigarette Smoke-Induced Genomic Instability

(1) Background: Chronic inflammation has been regarded as a risk factor for the onset and progression of human cancer, but the critical molecular mechanisms underlying this pathological process have yet to be elucidated. (2) Methods: In this study, we investigated whether interleukin (IL)-17-mediated inflammation was involved in cigarette smoke-induced genomic instability. (3) Results: Higher levels of both IL-17 and the DNA damage response (DDR) were found in the lung tissues of smokers than in those of non-smokers. Similarly, elevated levels of IL-17 and the DDR were observed in mice after cigarette smoke exposure, and a positive correlation was observed between IL-17 expression and the DDR. In line with these observations, the DDR in the mouse lung was diminished in IL-17 KO when exposed to cigarette smoke. Besides this, the treatment of human bronchial epithelium cells with IL-17 led to increased levels of the DDR and chromosome breakage. (4) Conclusions: These results suggest that cigarette smoke induces genomic instability at least partially through IL-17-mediated inflammation, implying that IL-17 could play an important role in the development of lung cancer.

Preclinical studies and the function of IL-17 cytokines in COPD

Chronic obstructive pulmonary disease (COPD) is among the leading causes of death worldwide and imposes a high economic burden to the health systems. COPD is characterized by chronic inflammation of the lung leading to airflow limitation, alveolar tissue destruction, and emphysema. Therefore, anti-inflammatory therapies for the treatment of COPD are of interest. In this review, we focus on the function of the IL-17 cytokines IL-17A and IL-17C, both known to mediate the recruitment of inflammatory cells, in the pathogenesis of COPD. We highlight that the expression of IL-17A and IL-17C is induced by pathogens frequently found in lungs of COPD patients and that targeting IL-17-signaling is an interesting option for the treatment of acute exacerbation of COPD.

Orchestration of Neutrophil Extracellular Traps (Nets), a Unique Innate Immune Function during Chronic Obstructive Pulmonary Disease (COPD) Development

Morbidity, mortality and economic burden caused by chronic obstructive pulmonary disease (COPD) is a significant global concern. Surprisingly, COPD is already the third leading cause of death worldwide, something that WHO had not predicted to occur until 2030. It is characterized by persistent respiratory symptoms and airway limitation due to airway and/or alveolar abnormalities usually caused by significant exposure to noxious particles of gases. Neutrophil is one of the key infiltrated innate immune cells in the lung during the pathogenesis of COPD. Neutrophils during pathogenic attack or injury decide to undergo for a suicidal death by releasing decondensed chromatin entangled with antimicrobial peptides to trap and ensnare pathogens. Casting neutrophil extracellular traps (NETs) has been widely demonstrated to be an effective mechanism against invading microorganisms thus controlling overwhelming infections. However, aberrant and massive NETs formation has been reported in several pulmonary diseases, including chronic obstructive pulmonary disease. Moreover, NETs can directly induce epithelial and endothelial cell death resulting in impairing pulmonary function and accelerating the progression of the disease. Therefore, understanding the regulatory mechanism of NET formation is the need of the hour in order to use NETs for beneficial purpose and controlling their involvement in disease exacerbation. For example, DNA neutralization of NET proteins using protease inhibitors and disintegration with recombinant human DNase would be helpful in controlling excess NETs. Targeting CXC chemokine receptor 2 (CXCR2) would also reduce neutrophilic inflammation, mucus production and neutrophil-proteinase mediated tissue destruction in lung. In this review, we discuss the interplay of NETs in the development and pathophysiology of COPD and how these NETs associated therapies could be leveraged to disrupt NETopathic inflammation as observed in COPD, for better management of the disease.

Immune defects in patients with pulmonary Mycobacterium abscessus disease without cystic fibrosis

The prevalence of Mycobacterium abscessus infections in non-cystic fibrosis (CF) patients has increased in recent years. In this study, we investigate whether immune defects explain the apparent susceptibility to this opportunistic infection in non-CF patients.

We performed stimulations of peripheral blood mononuclear cells and whole blood from 13 patients with M. abscessus pulmonary disease and 13 healthy controls to investigate their cytokine production after 24 h and 7 days.

Patients were predominantly women (54%) with a mean age of 59 years; 62% had nodular bronchiectatic disease. Many patients had predisposing pulmonary diseases, such as COPD (46%), and asthma (23%). Patients with COPD showed an impaired interleukin (IL)-6 response to M. abscessus and a reduced IL-17 response to Candida, together with a M. abscessus-specific enhanced IL-22 production. Patients without COPD showed higher levels of interleukin-1 receptor antagonist (IL-1Ra), an anti-inflammatory molecule. Within the non-COPD patients, those with bronchiectasis showed defective interferon (IFN)-γ production in response to Candida albicans.

In conclusion, susceptibility to M. abscessus is likely determined by a combination of immunological defects and predisposing pulmonary disease. The main defect in the innate immune response was a shift of the ratio of IL-1β to IL-1Ra, which decreased the bioactivity of this pathway in the adaptive immune response. In the adaptive immune response there was defective IL-17 and IFN-γ production. Patients with COPD and bronchiectasis showed different cytokine defects. It is therefore crucial to interpret the immunological results within the clinical background of the patients tested.

Measurement of defects in both the innate and adaptive immune responses in patients with M. abscessus pulmonary disease show that susceptibility to M. abscessus is determined by a combination of immunological defects and predisposing pulmonary diseasehttps://bit.ly/2DtbycY

Relationship of Serum Levels of IL-17, IL-18, TNF-α, and Lung Function Parameters in Patients with COPD, Asthma-COPD Overlap, and Bronchial Asthma

Determination of markers of systemic inflammation is one of the important directions in the study of pathogenesis and improvement of diagnosis of chronic obstructive pulmonary disease (COPD), asthma-COPD overlap (ACO), and bronchial asthma (BA). The aim of our work was a comparative study of the features of changes in serum levels of IL-17, IL-18, and TNF-α in patients with COPD, ACO, and BA with various severity of the disease, as well as evaluation of the relationship between the level of these cytokines and lung ventilation function. A total of 147 patients with COPD (n = 58), ACO (n = 57), and BA (n = 32) during a stable period have been examined in this study. The control group included 21 healthy nonsmokers with similar sex-age indicators. Serum levels of IL-17, IL-18, and TNF-α were determined by ELISA. The concentrations of these cytokines in the circulation in the studied patients with COPD, ACO, and BA were higher than those in healthy nonsmokers (p ≤ 0.001). IL-17 and IL-18 levels in the blood serum were comparable in all examined patients. The mean TNF-α concentrations in the circulation in COPD and ACO were significantly higher than those in BA (p < 0.001). In patients with COPD, the levels of IL-17 and TNF-α increased progressively against the background of a decrease in numerous spirometric indicators, which allows us to consider these cytokines as systemic biomarkers of disease severity. In BA, the inverse correlations between the level of IL-17 and FEV1/FVC (%) and FEV1 have been found. In patients with ACO, the increase in IL-18 levels was associated with a decrease in FEV1 and TNF-α with FEV1/FVC (%). These findings indicate that IL-17, IL-18, and TNF-α can participate in the mechanisms of systemic inflammation and the genesis of disorders of airway obstruction in COPD, AСO, and BA. An increase in the levels of IL-17 and TNF-α may be associated with impaired bronchial patency in COPD and BA. The established associations of the IL-18 concentration in the blood serum and FEV1 only in patients with ACO allow using the level of IL-18 as a potential marker of the degree of impaired airway obstruction in this disease.

Analysis of the Status of the Cutaneous Endogenous and Exogenous Antioxidative System of Smokers and the Short-Term Effect of Defined Smoking Thereon

The daily consumption of tobacco products leads to a boost in free radical production in tissues, promoting the risk for malignancies, metabolic alterations and chronic-inflammatory diseases. This study aimed to broaden the knowledge of the status of the antioxidative (AO) system in the skin, compared to the blood, of healthy appearing smokers. Both, the basic status compared to non-smokers and the short-term impact of controlled cigarette consumption in smokers were analyzed. Our study showed that the basic level of the AO system of smokers significantly differed from that of non-smokers. As determined by resonant Raman spectroscopy (RRS), the levels of exogenous AOs were decreased in both, the skin, in vivo (β-carotene and lycopene), and blood plasma (β-carotene only). In contrast, the levels of glutathione (GSH), the prototypical endogenous AO, which were analyzed by fluorimetric assays in cutaneous tape strips and blood plasma, were increased in the skin, although unchanged in the blood of smokers. Elevated cutaneous GSH levels were reflected by an elevated overall radical scavenging activity in the skin, as quantified by non-invasive electron paramagnetic resonance (EPR) spectroscopy. Analysis of the expression of selected stress-associated genes in blood immune cells by quantitative RT-PCR in subgroups of non-smokers and smokers additionally demonstrated the downregulation of AKR1C2 in smokers, and its negative correlation with blood plasma levels of the protective immune mediator interleukin-22, assessed by the ELISA technique. Controlled cigarette consumption did not alter exogenous or endogenous AOs in the skin of smokers, but decreased lycopene levels in blood plasma. Moreover, there was a decline in blood IL-22 levels, while no relevant response of blood cell gene expressions was found after the considered short time. Our data therefore demonstrate a strengthened endogenous AO status in the skin of smokers, which may indicate a long-term adaptation to chronic oxidative stress in this specific organ. While this effect was not clearly visible in the blood, this compartment seems to be useful as an immediate indicator of the body's AO consumption. Moreover, decreased levels of AKR1C2, which we show for the first time to be expressed in immune cells, may be a candidate marker for long-term smoking. In addition, this study demonstrates that the rate constant of a spin probe decline determined by EPR spectroscopy mainly represents the endogenous AO status of a tissue.

Effects of icariin on cell injury and glucocorticoid resistance in BEAS-2B cells exposed to cigarette smoke extract

Glucocorticoids (GCs) exert a therapeutic effect in numerous chronic inflammatory diseases. However, chronic obstructive pulmonary disease (COPD) tends to be GC-resistant. Icariin, a major component of flavonoids isolated from Epimedium brevicornum Maxim (Berberidaceae), significantly relieves symptoms in patients with COPD. However, the mechanism of action remains unclear and further investigation is required to establish whether it may serve as an alternative or complementary therapy for COPD. The aim of the present study was to determine the effects of icariin in human bronchial epithelial cells exposed to cigarette smoke extract (CSE) and to determine whether icariin reverses GC resistance. The results revealed that icariin significantly increased the proliferation of CSE-exposed cells. Furthermore, icariin significantly increased protein expression of the anti-inflammatory factor interleukin (IL)-10 and significantly decreased protein expression of the pro-inflammatory factors IL-8 and tumor necrosis factor α. Icariin also attenuated the expression of the cellular matrix remodelling biomarkers matrix metallopeptidase 9 and tissue inhibitor of metalloproteinase 1, and decreased the production of reactive oxygen species (ROS). In addition, icariin regulated the expression of GC resistance-related factors, such as GC receptors, histone deacetylase 2, nuclear factor erythroid-2-related factor 2 and nuclear factor κ B. The results obtained in the present study suggested that icariin may decrease CSE-induced inflammation, airway remodelling and ROS production by mitigating GC resistance. In conclusion, icariin may potentially be used in combination with GCs to increase therapeutic efficacy and reduce GC resistance in COPD.

Genetic variants in IL17A and serum levels of IL-17A are associated with COPD related to tobacco smoking and biomass burning

IL-17A is an important pro-inflammatory cytokine involved in the inflammatory response in chronic obstructive pulmonary disease (COPD). To evaluate the role played by single nucleotide polymorphisms of IL17A and protein levels in susceptibility to COPD, 1,807 subjects were included in a case-control study; 436 had COPD related to tobacco smoking (COPD-S) and 190 had COPD related to biomass burning (COPD-BB). Six hundred fifty-seven smokers without COPD (SWOC) and 183 biomass burning-exposed subjects (BBES) served as the respective control groups. The CC genotype and C allele of rs8193036 were associated with COPD (COPD-S vs. SWOC: p < 0.05; OR = 3.01, and OR = 1.28, respectively), as well as a recessive model (p < 0.01; OR = 2.91). Significant differences in serum levels were identified between COPD-S vs. SWOC, COPD-S vs. COPD-BB, and SWOC vs. BBES (p < 0.01). By comparing genotypes in the COPD-BB group TT vs. CC and TC vs. CC (p < 0.05), we found lower levels for the CC genotype. Logistic regression analysis by co-variables was performed, keeping the associations between COPD-S vs. SWOC with both polymorphisms evaluated (p < 0.05), as well as in COPD-BB vs. BBES but with a reduced risk of exacerbation (p < 0.05). In conclusion, polymorphisms in IL17A are associated with COPD. Serum levels of IL-17A were higher in smokers with and without COPD.

LncRNAs NR-026690 and ENST00000447867 are upregulated in CD4+ T cells in patients with acute exacerbation of COPD

Objective

The aim of the study was to determine the expression profile of long noncoding RNAs (lncRNAs) in CD4+ T cells from COPD patients and explore the clinical value of the lncRNAs.

Methods

First, microarray analysis was performed. Differentially expressed lncRNAs were validated by quantitative real-time reverse transcription-PCR (qRT-PCR) in samples from 56 patients with acute exacerbations of COPD (AECOPD), 56 patients with stable COPD, and 35 healthy controls. Meanwhile, the clinical value was tested by receiver operating characteristic curve analysis. The functions of lncRNAs were analyzed by the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes database. The potential target genes that might be regulated by NR-026690 and ENST00000447867 were identified by the lncRNA-mRNA network and competing endogenous RNA network. The transcriptional expression level of rap guanine nucleotide exchange factor 3 (RAPGEF3) was tested by qRT-PCR. The correlation of the expression between NR-026690, ENST00000447867, and RAPGEF3 was analyzed by Spearman's correlation test.

Results

We found that the relative expression levels of ENST00000447867 and NR-026690 in the CD4+ T cells of AECOPD patients were significantly higher than in the stable COPD patients and control subjects by microarray and qRT-PCR validation. The transcriptional expression level of RAPGEF3 in the CD4+ T cells was significantly higher in the AECOPD group compared to the control group (P<0.01) and the stable COPD group (P<0.05). RAPGEF3 expression was positively associated with NR-026690 (r=0.4925, P<0.01) and ENST00000447867 (r=0.4065, P<0.01).

Conclusion

NR-026690 and ENST00000447867 might be potential biomarkers for COPD. They might affect RAPGEF3 as miRNA sponges to regulate COPD development.

Impact of Genetic Polymorphisms on Human Immune Cell Gene Expression

While many genetic variants have been associated with risk for human diseases, how these variants affect gene expression in various cell types remains largely unknown. To address this gap, the DICE (database of immune cell expression, expression quantitative trait loci [eQTLs], and epigenomics) project was established. Considering all human immune cell types and conditions studied, we identified cis-eQTLs for a total of 12,254 unique genes, which represent 61% of all protein-coding genes expressed in these cell types. Strikingly, a large fraction (41%) of these genes showed a strong cis-association with genotype only in a single cell type. We also found that biological sex is associated with major differences in immune cell gene expression in a highly cell-specific manner. These datasets will help reveal the effects of disease risk-associated genetic polymorphisms on specific immune cell types, providing mechanistic insights into how they might influence pathogenesis (https://dice-database.org).

ATRA reduces inflammation and improves alveolar epithelium regeneration in emphysematous rat lung

INTRODUCTION

Pulmonary emphysema characterized by alveolar wall destruction is resultant of persistent chronic inflammation. All-trans retinoic acid (ATRA) has been reported to reverse elastase-induced emphysema in rats. However, the underlying molecular mechanisms are so far unknown.

OBJECTIVE

To investigate the therapeutic potential effect of ATRA via the amelioration of the ERK/JAK-STAT pathways in the lungs of emphysematous rats.

METHODS

In silico analysis was done to find the binding efficiency of ATRA with receptor and ligands of ERK & JAK-STAT pathway. Emphysema was induced by porcine pancreatic elastase in Sprague-Dawley rats and ATRA was supplemented as therapy. Lungs were harvested for histopathological, genomics and proteomics analysis.

RESULTS AND DISCUSSION

In silico docking, analysis confirms that ATRA interferes with the normal binding of ligands (TNF-α, IL6ST) and receptors (TNFR1, IL6) of ERK/JAK-STAT pathways respectively. ATRA restored the histology, proteases/antiproteases balance, levels of inflammatory markers, antioxidants, expression of candidate genes of ERK and JAK-STAT pathways in the therapy group.

CONCLUSION

ATRA ameliorates ERK/JAK-STAT pathway in emphysema condition, resulting in alveolar epithelium regeneration. Hence, ATRA may prove to be a potential drug in the treatment of emphysema.

Relationship of systemic IL-10 levels with proinflammatory cytokine responsiveness and lung function in agriculture workers

BACKGROUND

Agriculture workers are exposed to microbial component- and particulate matter-enriched organic dust aerosols. Whereas it is clear that exposure to these aerosols can lead to lung inflammation, it is not known how inflammatory responses are resolved in some individuals while others develop chronic lung disease. Interleukin (IL)-10 is an immunomodulatory cytokine that is recognized as a potent anti-inflammatory and pro-resolving factor. The objective of this study was to determine whether there is a relationship of systemic IL-10 and proinflammatory responses and/or respiratory health effects in humans with prior agriculture exposure.

METHODS

This is a cross sectional study of 625 veterans with > 2 years of farming experience. Whole blood was stimulated with or without organic dust and measured for IL-6, TNFα and IL-10. Participants underwent spirometry and respiratory symptoms were assessed by questionnaire.

RESULTS

We found that baseline IL-10 concentration from the whole blood assay was inversely associated with ΔTNF-α (r = - 0.63) and ΔIL-6 (r = - 0.37) levels. Results remained highly significant in the linear regression model after adjusting for age, sex, BMI, race, education, smoking status, and white blood cell count (ΔTNF-α, p < 0.0001; ΔIL-6, p < 0.0001). We found no association between chronic cough (p = 0.18), chronic phlegm (p = 0.31) and chronic bronchitis (p = 0.06) and baseline IL-10 levels using univariate logistic regression models. However, we did find that higher FEV1/FVC was significantly associated with increased baseline IL-10 concentration.

CONCLUSIONS

Collectively, these studies support a potential role for IL-10 in modulating an inflammatory response and lung function in agriculture-exposed persons.

Increased serum IL-17 and decreased serum IL-10 and IL-35 levels correlate with the progression of COPD

Purpose

This study aimed to measure the serum levels of interleukin (IL)-17, IL-10, and IL-35 in patients with stable chronic obstructive pulmonary disease (COPD) and disclose the correlations between their expression levels and clinical factors of patients.

Methods

A total of 75 patients with stable COPD (47 males and 28 females) and 30 healthy controls (15 males and 15 females) were included in this study. The serum levels of IL-17, IL-10, and IL-35 were determined by enzyme-linked immunosorbent assay. The correlations between their expression levels and clinical factors of patients were determined using linear regression methods.

Results

The serum level of IL-17 was upregulated in stable COPD, and increased IL-17 expression was positively correlated with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) grading, modified Medical Research Council (mMRC) score, and long clinical history (P<0.05), but negatively correlated with the pulmonary function (P<0.05) of patients. The serum levels of IL-10 and IL-35 were downregulated in stable COPD, and decreased IL-10 and IL-35 levels negatively correlated with the smoking status, GOLD grading, mMRC score, and long clinical history (P<0.05), but positively correlated with the pulmonary function (P<0.05) of patients. Moreover, the level of IL-17 negatively correlated with IL-10 and IL-35, but IL-10 positively correlated with IL-35.

Conclusion

The serum levels of IL-17, IL-10, and IL-35 correlated with the clinical factors of COPD, indicating that they can serve as indicators to estimate the progression of COPD.

IL22 Promotes Kras-Mutant Lung Cancer by Induction of a Protumor Immune Response and Protection of Stemness Properties

Somatic KRAS mutations are the most common oncogenic variants in lung cancer and are associated with poor prognosis. Using a Kras-induced lung cancer mouse model, CC-LR, we previously showed a role for inflammation in lung tumorigenesis through activation of the NF-κB pathway, along with induction of interleukin 6 (IL6) and an IL17-producing CD4+ T-helper cell response. IL22 is an effector molecule secreted by CD4+ and γδ T cells that we previously found to be expressed in CC-LR mice. IL22 mostly signals through the STAT3 pathway and is thought to act exclusively on nonhematopoietic cells with basal IL22 receptor (IL22R) expression on epithelial cells. Here, we found that higher expression of IL22R1 in patients with KRAS-mutant lung adenocarcinoma was an independent indicator of poor recurrence-free survival. We then showed that genetic ablation of Il22 in CC-LR mice (CC-LR/IL22KO mice) caused a significant reduction in tumor number and size. This was accompanied by significantly lower tumor cell proliferation, angiogenesis, and STAT3 activation. Il22 ablation was also associated with significant reduction in lung-infiltrating inflammatory cells and expression of protumor inflammatory cytokines. Conversely, this was accompanied with increased antitumor Th1 and cytotoxic CD8+ T-cell responses, while suppressing the protumor immunosuppressive T regulatory cell response. In CC-LR/IL22KO mice, we found significantly reduced expression of core stemness genes and the number of prototypical SPC+CCSP+ stem cells. Thus, we conclude that IL22 promotes Kras-mutant lung tumorigenesis by driving a protumor inflammatory microenvironment with proliferative, angiogenic, and stemness contextual cues in epithelial/tumor cells. Cancer Immunol Res; 6(7); 788-97. ©2018 AACR.

Changes in Th1/Th2-producing cytokines during acute exacerbation chronic obstructive pulmonary disease

Objective This study aimed to explore cytokine serum levels and the ratio of type 1 T helper (Th1)/Th2 cells in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods A total 245 patients diagnosed with AECOPD and 193 patients who progressed to stable COPD after the initiation of treatment in hospital were selected, while a further 50 healthy individuals served as controls. All patients with COPD were diagnosed using Global Initiative for Chronic Obstructive Lung Disease criteria. Serum concentrations of interleukin (IL)-2, interferon (IFN)-γ, IL-4, IL-10, IL-17, and immunoglobulin (Ig)E were measured using enzyme-linked immunosorbent assays. Results AECOPD patients had higher levels of IL-2, IFN-γ, IL-4, IL-10, IL-17, and IgE than those with stable COPD or controls. Intriguingly, the ratios of Th1/Th2 and IL-17/IgE were lower in AECOPD patients compared with the other two groups. These data suggest that AECOPD patients produce more IgE and have more differentiated Th2 cells than other groups. Conclusion Our findings suggest that an imbalance of circulating CD4⁺ T cell subsets correlates with AECOPD, and that a shift of Th1/Th2 and IL-17/IgE ratios may be caused by increased Th2 cell production.

Blood MCP-1 levels are increased in chronic obstructive pulmonary disease patients with prevalent emphysema

Background and aims

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by different phenotypes with either bronchial airways alterations or emphysema prevailing. As blood biomarkers could be clinically useful for COPD stratification, we aimed at investigating the levels of blood biomarkers in COPD patients differentiated by phenotype: prevalent chronic airway disease versus emphysema.

Methods

In 23 COPD patients with prevalent airway disease (COPD-B), 22 COPD patients with prevalent emphysema (COPD-E), 9 control smokers (CSs), and 18 control nonsmokers (CNSs), we analyzed the expression levels of interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, epidermal growth factor (EGF), monocyte chemotactic protein (MCP)-1, and vascular endothelial growth factor by enzyme-linked immunosorbent assay in plasma/serum; glutathione peroxidase and superoxide dismutase (SOD)-1 by immunochemical kits in plasma; and free F2-isoprostanes (F2-IsoPs) by gas chromatography in plasma.

Results

F2-IsoPs level was increased in COPD-B and COPD-E compared with CSs and CNSs; in addition, CS showed higher levels than CNSs; SOD1 level was lower in COPD-B and COPD-E than that in CNSs. Interestingly, MCP-1 level was higher only in COPD-E versus CSs and CNSs; EGF and IL-8 levels were higher in COPD-B and COPD-E versus CNSs; IL-6 level was increased in all three smoking groups (COPD-B, COPD-E, and CSs) versus CNS; IFN-γ and IL-1α levels were higher in CSs than in CNSs; and IL-1α level was also higher in CSs versus COPD-B and COPD-E. In all subjects, F2-IsoPs level correlated positively and significantly with MCP-1, IL-2, IL-1β, IFN-γ, and TNF-α and negatively with SOD1. When correlations were restricted to COPD-E and COPD-B groups, F2-IsoPs maintained the positive associations with IFN-γ, TNF-α, and IL-2.

Conclusion

We did not find any specific blood biomarkers that could differentiate COPD patients with prevalent airway disease from those with prevalent emphysema. The MCP-1 increase in COPD-E, associated with the imbalance of oxidant/antioxidant markers, may play a role in inducing emphysema.

Interleukin-22 attenuates double-stranded RNA-induced upregulation of PD-L1 in airway epithelial cells via a STAT3-dependent mechanism

Double-stranded RNA derived from viruses induces host immune responses. PD-L1, also known as B7-H1, is an immune-checkpoint molecule associated with the escape of viruses from host immune systems, which plays a role in the persistence of viral infection, resulting in exacerbations of underlying diseases such as asthma and chronic obstructive pulmonary disease. Interleukin (IL)-22 is produced from various immune cells and has protective properties on mucosal tissue. The binding of IL-22 to IL-22 receptor induces STAT3 activation. We investigated the effect of IL-22 on the expression in airway epithelial cells in vitro and in mouse lungs in vivo after the stimulation with an analog of viral double-stranded RNA, polyinosinic-polycytidylic acid (poly I:C). Stimulation with poly I:C upregulated PD-L1 expression on BEAS-2B cells. This upregulation of PD-L1 was attenuated by IL-22 administration. STAT3 phosphorylation was induced by IL-22 and poly I:C. Treatment of cells with STAT3 siRNA abolished the effect of IL-22 on the poly I:C-induced upregulation of PD-L1. This upregulation of PD-L1 was also attenuated by IL-11, a cytokine inducing STAT3 phosphorylation, in BEAS-2B cells. In mouse lung cells in vivo, IL-22 suppressed poly I:C-induced upregulation of PD-L1. These results suggest that IL-22 attenuates virus-induced upregulation of PD-L1 in airway epithelial cells via a STAT3-dependent mechanism.

The value of blood cytokines and chemokines in assessing COPD

BACKGROUND

Blood biomarkers are increasingly used to stratify high risk chronic obstructive pulmonary disease (COPD) patients; however, there are fewer studies that have investigated multiple biomarkers and replicated in multiple large well-characterized cohorts of susceptible current and former smokers.

METHODS

We used two MSD multiplex panels to measure 9 cytokines and chemokines in 2123 subjects from COPDGene and 1117 subjects from SPIROMICS. These biomarkers included: interleukin (IL)-2, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, eotaxin/CCL-11, eotaxin-3/CCL-26, and thymus and activation-regulated chemokine (TARC)/CCL-17. Regression models adjusted for clinical covariates were used to determine which biomarkers were associated with the following COPD phenotypes: airflow obstruction (forced expiratory flow at 1 s (FEV1%) and FEV1/forced vital capacity (FEV1/FVC), chronic bronchitis, COPD exacerbations, and emphysema. Biomarker-genotype associations were assessed by genome-wide association of single nucleotide polymorphisms (SNPs).

RESULTS

Eotaxin and IL-6 were strongly associated with airflow obstruction and accounted for 3-5% of the measurement variance on top of clinical variables. IL-6 was associated with progressive airflow obstruction over 5 years and both IL-6 and IL-8 were associated with progressive emphysema over 5 years. None of the biomarkers were consistently associated with chronic bronchitis or COPD exacerbations. We identified one novel SNP (rs9302690 SNP) that was associated with CCL17 plasma measurements.

CONCLUSION

When assessing smoking related pulmonary disease, biomarkers of inflammation such as IL-2, IL-6, IL-8, and eotaxin may add additional modest predictive value on top of clinical variables alone.

TRIAL REGISTRATION

COPDGene (ClinicalTrials.gov Identifier: NCT02445183 ). Subpopulations and Intermediate Outcomes Measures in COPD Study (SPIROMICS) ( ClinicalTrials.gov Identifier: NCT 01969344 ).

Th17 cytokines: novel potential therapeutic targets for COPD pathogenesis and exacerbations

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease of the airways caused mainly by cigarette smoke exposure. COPD progression is marked by exacerbations of the disease, often associated with infections. Recent data show the involvement in COPD pathophysiology of interleukin (IL)-17 and IL-22, two cytokines that are important in the control of lung inflammation and infection. During the initiation and progression of the disease, increased IL-17 secretion causes neutrophil recruitment, leading to chronic inflammation, airways obstruction and emphysema. In the established phase of COPD, a defective IL-22 response facilitates pathogen-associated infections and disease exacerbations. Altered production of these cytokines involves a complex network of immune cells and dysfunction of antigen-presenting cells. In this review, we describe current knowledge on the involvement of IL-17 and IL-22 in COPD pathophysiology at steady state and during exacerbations, and discuss implications for COPD management and future therapeutic approaches.

Targeting Interleukin-17 signalling in cigarette smoke-induced lung disease: Mechanistic concepts and therapeutic opportunities

It is widely accepted that compromised lung function in chronic obstructive pulmonary disease (COPD) is, at least in part, a consequence of persistent airway inflammation caused by particles and noxious gases present in cigarette smoke and indoor air pollution from burning biomass fuel. Currently, the World Health Organization estimates that 80 million people have moderate or severe COPD worldwide. While there is a global need for effective medical treatment, current therapeutic interventions have shown limited success in preventing disease pathology and progression. This is, in large part, due to the complexity and heterogeneity of COPD, and an incomplete understanding of the molecular mechanisms governing inflammatory processes in individual patients. This review discusses recent discoveries related to the pro-inflammatory cytokine interleukin (IL)-17A, and its potential role in the pathogenesis of COPD. We propose that an intervention strategy targeting IL-17 signalling offers an exciting opportunity to mitigate inflammatory processes, and prevent the progression of tissue pathologies associated with COPD.

Airway inflammation in chronic obstructive pulmonary disease (COPD): a true paradox

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is primarily an airway condition, which mainly affects cigarette smokers and presents with shortness of breath that is progressive and poorly reversible. In COPD research, there has been a long held belief that airway disease progression is due to inflammation. Although this may be true in the airway lumen with innate immunity activated by the effect of smoke or secondary to infection, the accurate picture of inflammatory cells in the airway wall, where the pathophysiological COPD remodeling occurs, is uncertain and debatable. Areas covered: The current review provides a comprehensive literature survey of the changes in the main inflammatory cells in human COPD patients and focuses on contrarian views that affect the prevailing dogma on inflammation. The review also delves into the role of oxidative stress and inflammasomes in modulating the immune response in COPD. Further, the effects of inflammation in affecting the epithelium, fibroblasts, and airway remodeling are discussed. Expert commentary: Inflammation as a driving force for airway wall damage and remodelling in early COPD is at the very least 'oversimplified' and is likely to be misleading. This has serious implications for rational thinking about the illness, including pathogenesis and designing therapy.

A Review of Pulmonary Toxicity of Electronic Cigarettes in the Context of Smoking: A Focus on Inflammation

The use of electronic cigarettes (e-cigs) is increasing rapidly, but their effects on lung toxicity are largely unknown. Smoking is a well-established cause of lung cancer and respiratory disease, in part through inflammation. It is plausible that e-cig use might affect similar inflammatory pathways. E-cigs are used by some smokers as an aid for quitting or smoking reduction, and by never smokers (e.g., adolescents and young adults). The relative effects for impacting disease risk may differ for these groups. Cell culture and experimental animal data indicate that e-cigs have the potential for inducing inflammation, albeit much less than smoking. Human studies show that e-cig use in smokers is associated with substantial reductions in blood or urinary biomarkers of tobacco toxicants when completely switching and somewhat for dual use. However, the extent to which these biomarkers are surrogates for potential lung toxicity remains unclear. The FDA now has regulatory authority over e-cigs and can regulate product and e-liquid design features, such as nicotine content and delivery, voltage, e-liquid formulations, and flavors. All of these factors may impact pulmonary toxicity. This review summarizes current data on pulmonary inflammation related to both smoking and e-cig use, with a focus on human lung biomarkers. Cancer Epidemiol Biomarkers Prev; 26(8); 1175-91. ©2017 AACR.

Serum IL-1β and IL-17 levels in patients with COPD: associations with clinical parameters

COPD is a chronic airway inflammatory disease characterized mainly by neutrophil airway infiltrations. Interleukin (IL)-1β and IL-17 are the key mediators of neutrophilic airway inflammation in COPD. This study was undertaken to evaluate the serum IL-1β and IL-17 levels and associations between these two key mediators with clinical parameters in COPD patients. Serum samples were collected from 60 COPD subjects during the acute exacerbation of COPD, 60 subjects with stable COPD and 40 healthy control subjects. Commercial enzyme-linked immunosorbent assay kits were used to measure the serum IL-1β and IL-17 concentrations. The association between serum IL-1β and IL-17 with FEV₁% predicted, C-reactive protein, neutrophil percentage and smoking status (pack-years) was assessed in the COPD patients. We found that serum IL-1β and IL-17 levels in acute exacerbation of COPD subjects were significantly higher than that in stable COPD or control subjects and were positively correlated to serum C-reactive protein levels, neutrophil % and smoking status (pack-years) but negatively correlated with FEV₁% predicted in COPD patients. More importantly, serum IL-1β levels were markedly positively associated with serum IL-17 levels in patients with COPD (P=0.741, P<0.001). In conclusion, elevated serum IL-1β and IL-17 levels may be used as a biomarker for indicating persistent neutrophilic airway inflammation and potential ongoing exacerbation of COPD.

HDAC1-3 inhibitor MS-275 enhances IL10 expression in RAW264.7 macrophages and reduces cigarette smoke-induced airway inflammation in mice

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.

Subtyping Chronic Obstructive Pulmonary Disease Using Peripheral Blood Proteomics

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disorder. COPD patients may have different clinical features, imaging characteristics and natural history. Multiple studies have investigated heterogeneity using statistical methods such as unsupervised clustering to define different subgroups of COPD based largely on clinical phenotypes. Some studies have performed clustering using genetic data or limited numbers of blood biomarkers. Our primary goal was to use proteomic data to find subtypes of COPD within clinically similar individuals. In the Treatment of Emphysema with a gamma-Selective Retinoid Agonist (TESRA) study, multiplex biomarker panels were run in serum samples collected prior to randomization. After implementing an algorithm to minimize missing values, the dataset included 396 COPD individuals and 87 biomarkers. Using hierarchical clustering, we identified 3 COPD subgroups, containing 267 (67.4%), 104 (26.3%), and 25 (6.3%) individuals, respectively. The third cluster had less emphysema on quantitative analysis of chest computed tomography scans (p=0.03) and worse disease-related quality of life based on the St. George's Respiratory Questionnaire (total score cluster 1: 45.6, cluster 2: 45.4, cluster 3: 56.6; p=0.01), despite similar levels of lung function impairment (forced expiratory volume in 1 second (49.2%, 49.2%, 48.2 % predicted, respectively). Enrichment analysis showed the biomarkers distinguishing cluster 3 mapped to platelet alpha granule and cell chemotaxis pathways. Thus, we identified a subgroup which has less emphysema but may have greater inflammation, which could be potentially targeted with anti-inflammatory therapies.

Role of IL-17A in murine models of COPD airway disease

Small airway fibrosis is a major pathological feature of chronic obstructive pulmonary disease (COPD) and is refractory to current treatments. Chronic inflammatory cells accumulate around small airways in COPD and are thought to play a major role in small airway fibrosis. Mice deficient in α/β T cells have recently been shown to be protected from both experimental airway inflammation and fibrosis. In these models, CD4+Th17 cells and secretion of IL-17A are increased. However, a pathogenic role for IL-17 in specifically mediating fibrosis around airways has not been demonstrated. Here a role for IL-17A in airway fibrosis was demonstrated using mice deficient in the IL-17 receptor A (il17ra) Il17ra-deficient mice were protected from both airway inflammation and fibrosis in two different models of airway fibrosis that employ COPD-relevant stimuli. In these models, CD4+ Th17 are a major source of IL-17A with other expressing cell types including γδ T cells, type 3 innate lymphoid cells, polymorphonuclear cells, and CD8+ T cells. Antibody neutralization of IL-17RA or IL-17A confirmed that IL-17A was the relevant pathogenic IL-17 isoform and IL-17RA was the relevant receptor in airway inflammation and fibrosis. These results demonstrate that the IL-17A/IL-17 RA axis is crucial to murine airway fibrosis. These findings suggest that IL-17 might be targeted to prevent the progression of airway fibrosis in COPD.

Distal airway dysfunction identifies pulmonary inflammation in asymptomatic smokers

Smoking induced inflammation leads to distal airway destruction. However, the relationship between distal airway dysfunction and inflammation remains unclear, particularly in smokers prior to the development of airway obstruction.

Seven normal controls and 16 smokers without chronic obstructive pulmonary disease (COPD) were studied. Respiratory function was assessed using the forced oscillation technique (FOT). Abnormal FOT was defined as elevated resistance at 5 Hz (R₅). Parameters reflecting distal lung function included frequency dependence of resistance (R_5–20) and dynamic elastance (X₅). Inflammation was quantified in concentrated bronchoalveolar lavage utilising cell count differential and cytokines expressed as concentration per mL epithelial lining fluid.

All control subjects and seven smokers had normal R₅. Nine smokers had elevated R₅ with abnormal R_5–20 and X₅, indicating distal lung dysfunction. The presence of abnormal FOT was associated with two-fold higher lymphocyte and neutrophil counts (p<0.025) and with higher interleukin (IL)-8, eotaxin and fractalkine levels (p<0.01). Reactivity of R_5–20 and X₅ correlated with levels of IL-8, eotaxin, fractalkine, IL-12p70 and transforming growth factor-α (r>0.47, p<0.01).

Distal airway dysfunction in smokers without COPD identifies the presence of distal lung inflammation that parallel reported observations in established COPD. These findings were not evident on routine pulmonary function testing and may allow the identification of smokers at risk of progression to COPD.

Isolated dysfunction in distal airways identifies pulmonary inflammation in asymptomatic smokers with normal airflowhttp://ow.ly/8bVk305aVkj

Non-small cell lung cancer is characterised by a distinct inflammatory signature in serum compared with chronic obstructive pulmonary disease

Development of lung cancer is closely related to smoking in a majority of patients. Most smokers, however, do not develop lung cancer in spite of a high mutational load accumulating in the lung tissue. Here we investigate whether a cancer-specific footprint can be revealed by investigating circulating inflammatory markers in patients with non-small cell lung cancer (NSCLC) compared with patients with chronic obstructive pulmonary disease (COPD), both cohorts characterised by similar smoking history. Serum concentrations of 57 cytokines and matrix metalloproteinases (MMPs) from 43 patients with advanced NSCLC were evaluated by multiplex immunoassays and compared with serum samples from 35 patients with COPD. Unsupervised hierarchical clustering and non-parametric analyses were performed. False discovery rate was used to adjust for multiple testing. Clustering of cytokine and MMP concentrations in the serum revealed a distinct separation of the NSCLC patients from the COPD group. Individual concentrations of thymus and activation-regulated cytokine (C-C motif chemokine ligand 17), Gro-b (C-X-C motif chemokine ligand 2 (CXCL2)), CXCL13, interleukin (IL)-1ra, IL-6, IL-8 (CXCL8), IL-16, IL-17A, macrophage migration inhibitory factor (MIF), granulocyte colony-stimulating factor, platelet-derived growth factor subunit B, MMP-2, MMP-8 and MMP-12 were significantly different in serum from NSCLC and COPD patients. Moreover, the interferon-γ/IL-10 ratio was lower in cancer patients compared with COPD patients, consistent with a cytokine milieu favouring tumour tolerance. Our results suggest that NSCLC is characterised by a distinct inflammatory signature in serum. The different cytokine profiles in NSCLC and COPD patients may represent tumour-promoting and tumour-suppressing immune responses developing in response to mucosal inflammation and mutations induced by smoking.

Structurally Related Monoterpenes p-Cymene, Carvacrol and Thymol Isolated from Essential Oil from Leaves of Lippia sidoides Cham. (Verbenaceae) Protect Mice against Elastase-Induced Emphysema

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by irreversible airflow obstruction and inflammation. Natural products, such as monoterpenes, displayed anti-inflammatory and anti-oxidant activities and can be used as a source of new compounds to COPD treatment. Our aim was to evaluate, in an elastase-induced pulmonary emphysema in mice, the effects of and underlying mechanisms of three related natural monoterpenes (p-cymene, carvacrol and thymol) isolated from essential oil from leaves Lippia sidoides Cham. (Verbenaceae).

METHODS

Mices received porcine pancreatic elastase (PPE) and were treated with p-cymene, carvacrol, thymol or vehicle 30 min later and again on 7th, 14th and 28th days. Lung inflammatory profile and histological sections were evaluated.

RESULTS

In the elastase-instilled animals, the tested monoterpenes reduced alveolar enlargement, macrophages and the levels of IL-1β, IL-6, IL-8 and IL-17 in bronchoalveolar lavage fluid (BALF), and collagen fibers, MMP-9 and p-65-NF-κB-positive cells in lung parenchyma (p < 0.05). All treatments attenuated levels of 8-iso-PGF2α but only thymol was able to reduced exhaled nitric oxide (p < 0.05).

CONCLUSION

Monoterpenes p-cymene, carvacrol and thymol reduced lung emphysema and inflammation in mice. No significant differences among the three monoterpenes treatments were found, suggesting that the presence of hydroxyl group in the molecular structure of thymol and carvacrol do not play a central role in the anti-inflammatory effects.