Paradoxical effects of cigarette smoke and COPD on SARS-CoV-2 infection and disease.

BACKGROUND: How cigarette smoke (CS) and chronic obstructive pulmonary disease (COPD) affect severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection and severity is controversial. We investigated the effects of COPD and CS on the expression of SARS-CoV-2 entry receptor ACE2 in vivo in COPD patients and controls and in CS-exposed mice, and the effects of CS on SARS-CoV-2 infection in human bronchial epithelial cells in vitro. METHODS: We quantified: (1) pulmonary ACE2 protein levels by immunostaining and ELISA, and both ACE2 and/or TMPRSS2 mRNA levels by RT-qPCR in two independent human cohorts; and (2) pulmonary ACE2 protein levels by immunostaining and ELISA in C57BL/6 WT mice exposed to air or CS for up to 6 months. The effects of CS exposure on SARS-CoV-2 infection were evaluated after in vitro infection of Calu-3 cells and differentiated human bronchial epithelial cells (HBECs), respectively. RESULTS: ACE2 protein and mRNA levels were decreased in peripheral airways from COPD patients versus controls but similar in central airways. Mice exposed to CS had decreased ACE2 protein levels in their bronchial and alveolar epithelia versus air-exposed mice. CS treatment decreased viral replication in Calu-3 cells, as determined by immunofluorescence staining for replicative double-stranded RNA (dsRNA) and western blot for viral N protein. Acute CS exposure decreased in vitro SARS-CoV-2 replication in HBECs, as determined by plaque assay and RT-qPCR. CONCLUSIONS: ACE2 levels were decreased in both bronchial and alveolar epithelial cells from COPD patients versus controls, and from CS-exposed versus air-exposed mice. CS-pre-exposure potently inhibited SARS-CoV-2 replication in vitro. These findings urge to investigate further the controversial effects of CS and COPD on SARS-CoV-2 infection.

Th2 cytokines impair innate immune responses to rhinovirus in respiratory epithelial cells.

BACKGROUND: Asthma and other Th2 inflammatory conditions have been associated with increased susceptibility to viral infections. The mechanisms by which Th2 cytokines can influence immune responses to infections are largely unknown. METHODS: We measured the effects of Th2 cytokines (IL-4 and IL-13) on bronchial epithelial cell innate immune antiviral responses by assessing interferon (IFN-ß and IFN-λ1) induction following rhinovirus (RV)-16 infection. We also investigated the modulatory effects of Th2 cytokines on Toll-like receptor 3 (TLR3), interferon-responsive factor 3 (IRF3) and nuclear factor (NF)-kB, that is key molecules and transcription factors involved in the rhinovirus-induced interferon production and inflammatory cascade. Pharmacological and redox modulation of these pathways was also assessed. RESULTS: Th2 cytokines impaired RV-16-induced interferon production, increased rhinovirus replication and impaired TLR3 expression in bronchial epithelial cells. These results were replicated in vivo: we found increased IL-4 mRNA levels in nasal epithelial cells from nasal brushing of atopic rhinitis patients and a parallel reduction in TLR3 expression and increased RV-16 replication compared to nonatopic subjects. Mechanistically, Th2 cytokines impaired RV-16-induced activation of IRF3, but had no effects on RV-16-induced NF-kB activation in bronchial epithelial cell cultures. N-acetylcysteine and phosphoinositide 3-kinase (PI3K) inhibitor restored the inhibitory effects of Th2 cytokines over RV-16-induced activation of IRF3. CONCLUSIONS: IL-4 and IL-13, through inhibition of TLR3 expression and signalling (IRF3), impair immune response to RV-16 infection. These data suggest that Th2 conditions increase susceptibility to infections and identify pharmacological approaches with potential to restore impaired immune response in these conditions.

A valid option for asthma control: Clinical evidence on efficacy and safety of fluticasone propionate/formoterol combination in a single inhaler.

A good level of asthma control improves the quality of life of asthmatic patients and may prevent future risk in term of exacerbations and decline of pulmonary function. However, in a real-life setting, several factors contribute to generally low compliance to the treatment. A rapid-onset, long-lasting medication with few adverse effects may contribute to improve adherence to therapy, along with an effective patient education and a good physician-patient communication. Many clinical studies demonstrated the comparable efficacy of the new fluticasone propionate/formoterol (FP/F) combination in a single inhaler to other combinations of inhaled corticosteroids and ß2agonists and the superiority of FP/F as compared to its individual components. Also the safety profile of this combination was encouraging in all studies, even at higher doses. By effectively and safely targeting both airway inflammation and smooth muscle dysfunction, the two pathological facets of asthma, and allowing the patient to adapt dose strength, FP/F combination in a single device represents a valid option to improve asthma control in patients with different levels of asthma severity.

Differences in the efficacy and safety among inhaled corticosteroids (ICS)/long-acting beta2-agonists (LABA) combinations in the treatment of chronic obstructive pulmonary disease (COPD): Role of ICS.

Inhaled corticosteroids (ICS) are frequently recommended for the treatment of asthma and COPD, often in combination with long-acting beta2-agonists (LABA), depending on the severity of the disease and/or on the specific phenotype. Several ICS/LABA combinations are currently available that differ in their pharmacokinetic characteristics and dose of both components. Thus, this review assesses differences in the efficacy and the safety profiles of the ICS components in the two more frequently used ICS/LABA combinations (budesonide/formoterol and fluticasone/salmeterol) for the management of COPD. Whereas the basic mechanism of action is similar for all ICS (binding with the intracellular glucocorticoid receptor, which mediates both genomic and non genomic effects), the pharmacokinetic and characteristics of ICS are quite different in terms of receptor affinity, bioavailability, lipophilicity and drug persistence in the airways. Fluticasone persists longer in airway mucus and requires more time to dissolve in the lining fluid and then enter the airway wall, whereas budesonide is cleared more quickly from the airways. Comparative efficacy of the two major ICS/LABA combinations recommended for the treatment of COPD show similar efficacy in terms of reduction of exacerbations, improvement in forced expiratory volume in the first second (FEV1) and quality of life. One retrospective cohort study suggested a greater efficacy for the budesonide/formoterol combination on hospital or emergency department admissions, oral corticosteroid courses, and addition of tiotropium, and an observational real-life study reported a greater reduction of COPD exacerbations with budesonide/formoterol than with fluticasom/salmeterol combination. Among the potential side effects of chronic ICS treatment in patients with COPD, recently the use of fluticasone or fluticasone/salmeterol combination has been associated with a higher prevalence of pneumonia in the major long-term studies. On the other hand, no similar increased risk of pneumonia has been reported in patients with COPD treated with the budesonide/formoterol combination. A recent population-based cohort study from the Quebec database showed that the adjusted odds ratio for having severe pneumonia was higher for fluticasone (2.1) than for budesonide (1.17) or other ICS (1.41). Of the ICS studied, only fluticasone demonstrated a dose-related increase in risk of pneumonia in patients with COPD. This difference between fluticasone and budesonide may be explained by the longer retention of fluticasone in the airways, with potentially greater inhibition of type-1 innate immunity. Therefore, the risk:benefit ratio should be evaluated thoroughly when choosing an ICS/LABA combination for patients with COPD.

COPD: early diagnosis and treatment to slow disease progression.

AIMS: Chronic obstructive pulmonary disease (COPD) is usually a progressive condition. Undiagnosed early-stage disease, particularly in symptomatic patients, is likely to become more severe with time. Hence, prevention or reduction in disease progression is highly relevant. We evaluated the published data and discussed the potential impact of early intervention on the course of COPD. METHODS: We performed PubMed searches of studies in early or mild COPD, focusing on those relating to lung function decline. RESULTS: Smoking cessation reduced lung function decline at all stages of COPD, and the earlier the intervention, the greater the impact on lung function. Accumulating data from placebo-controlled trials suggested that long-acting bronchodilators can slow the decline in lung function, as well as reduce exacerbation and mortality rates and improve health-related quality of life (HRQoL) in patients with mild-to-moderate COPD. Inhaled corticosteroids (ICS) do not impact lung function in early COPD, and further research is needed on the role of long-acting ß2-agonist-ICS combination therapy in these patients. CONCLUSIONS: Initiating treatment early in the course of COPD is likely to slow disease progression and improve HRQoL. Current data support maintenance treatment with a long-acting bronchodilator in this patient group. However, many questions remain unanswered regarding the optimal treatment of mild COPD, and further research is required to develop evidence-based recommendations in this field.

Frequent exacerbators--a distinct phenotype of severe asthma.

BACKGROUND: Exacerbations represent a major source of morbidity and mortality in asthma and are a prominent feature of poorly controlled, difficult-to-treat disease. OBJECTIVE: The goal of our study was to provide a detailed characterization of the frequent exacerbator phenotype and to identify risk factors associated with frequent and seasonal exacerbations. METHODS: Ninety-three severe asthmatics (SA) and 76 mild-to-moderate patients (MA) were screened and prospectively followed up for 1 year (NCT00555607). Medical history, baseline clinical data and biomarkers were used to assess risk factors for frequent exacerbations. RESULTS: During the study, 104 exacerbations were recorded in the SA group and 18 in the MA. Frequent exacerbators were characterized by use of higher doses of inhaled (1700 vs. 800 µg) and oral (6.7 vs. 1.7 mg) glucocorticosteroids, worse asthma control (ACQ score 2.3 vs. 1.4), lower quality of life (SGRQ score 48.5 vs. 33.3), higher sputum eosinophils (25.7% vs. 8.2%) and a more rapid decline in FEV1 /FVC ratio (-0.07 vs. -0.01 ΔFEV1 /FVC, frequent vs. non-frequent, respectively, P < 0.05). Exhaled NO > 45 p.p.b. and a history of smoking were associated with an increased risk of frequent exacerbations (odds ratios: 4.32 and 2.90 respectively). CONCLUSION AND CLINICAL RELEVANCE: We were able to distinguish and characterize a subphenotype of asthma subjects--frequent exacerbators--who are significantly more prone to exacerbations. Patients with FeNO > 45 p.p.b. and a history of smoking are at increased risk of frequent exacerbations and require careful monitoring in clinical practice.

Stability of phenotypes defined by physiological variables and biomarkers in adults with asthma.

BACKGROUND: Although asthma is characterized by variable airways obstruction, most studies of asthma phenotypes are cross-sectional. The stability of phenotypes defined either by biomarkers or by physiological variables was assessed by repeated measures over 1 year in the Pan-European BIOAIR cohort of adult asthmatics. METHODS: A total of 169 patients, 93 with severe asthma (SA) and 76 with mild-to-moderate asthma (MA), were examined at six or more visits during 1 year. Asthma phenotype clusters were defined by physiological variables (lung function, reversibility and age of onset of the disease) or by biomarkers (eosinophils and neutrophils in induced sputum). RESULTS: After 1 year of follow-up, the allocation to clusters was changed in 23.6% of all asthma patients when defined by physiological phenotypes and, remarkably, in 42.3% of the patients when stratified according to sputum cellularity (P = 0.034). In the SA cohort, 30% and 48.6% of the patients changed allocation according to physiological and biomarker clustering, respectively. Variability of phenotypes was not influenced by change in oral or inhaled corticosteroid dose, nor by the number of exacerbations. Lower stability of single and repeated measure was found for all evaluated biomarkers (eosinophils, neutrophils and FeNO) in contrast to good stability of physiological variables (FEV1 ), quality of life and asthma control. CONCLUSION: Phenotypes determined by biomarkers are less stable than those defined by physiological variables, especially in severe asthmatics. The data also imply that definition of asthma phenotypes is improved by repeated measures to account for fluctuations in lung function, biomarkers and asthma control.

Randomized Controlled Trials and real life studies. Approaches and methodologies: a clinical point of view.

Randomized Controlled Trials (RCTs) are the "gold standard" for evaluating treatment outcomes providing information on treatments "efficacy". They are designed to test a therapeutic hypothesis under optimal setting in the absence of confounding factors. For this reason they have high internal validity. The strict and controlled conditions in which they are conducted, leads to low generalizability because they are performed in conditions very different from real life usual care. Conversely, real life studies inform on the "effectiveness" of a treatment, that is, the measure of the extent to which an intervention does what is intended to do in routine circumstances. At variance to RCTs, real life trials have high generalizability, but low internal validity. Recently the number of real life studies has been rapidly growing in different areas of respiratory medicine, particularly in asthma and COPD. The role of such studies is becoming a hot topic in respiratory medicine, attracting research interest and debate. In the first part of this review we discuss some of the advantages and disadvantages of different types of RCTs and analyze the strengths and weaknesses of real life trials, considering the recent examples of some studies conducted in COPD. We then discuss methodological approaches and options to overcome some of the limitations of real life studies. Comparing the conclusions of effectiveness and efficacy trials can provide important pieces of information. Indeed, these approaches can result complementary, and they can guide the interpretation of each other results.

Author Correction: Intravenous N-acetylcysteine in respiratory disease with abnormal mucus secretion.

Eur Rev Med Pharmacol Sci 2023; 27 (11): 5119-5127-DOI: 10.26355/eurrev_202306_32628-PMID: 37318485, published online on June 13, 2023. After publication, the authors have found some mistakes. This erratum corrects the following: In Figure 1, "4 withdrawal" has been corrected into "7 withdrawal" and "95 completed study" has been corrected into "97 corrected study" In the "Efficacy" paragraph at page 5123, "1.0 in the placebo group" has been corrected into "-1.0 in the placebo group". The legend of Table V has been corrected as follows: Table V. Published clinical studies of the mucolytic and expectorant efficacy of IV NAC in respiratory diseases. In Table V, the data regarding the Treatment groups (duration) by Grassi et al5 have been corrected as follows: NAC oral 200 mg TID NAC IM 300 mg BID NAC IV 500 mg OD (6 days) In Table V, the data regarding the Treatment groups (duration) by Henneghien et al8 have been corrected as follows: NAC oral 200 mg TID NAC IV 300 mg TID (3-10 days) NAC IV 500 mg BID (12 days) There are amendments to this paper. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/32628.

EAACI position statement on asthma exacerbations and severe asthma.

Asthma exacerbations and severe asthma are linked with high morbidity, significant mortality and high treatment costs. Recurrent asthma exacerbations cause a decline in lung function and, in childhood, are linked to development of persistent asthma. This position paper, from the European Academy of Allergy and Clinical Immunology, highlights the shortcomings of current treatment guidelines for patients suffering from frequent asthma exacerbations and those with difficult-to-treat asthma and severe treatment-resistant asthma. It reviews current evidence that supports a call for increased awareness of (i) the seriousness of asthma exacerbations and (ii) the need for novel treatment strategies in specific forms of severe treatment-resistant asthma. There is strong evidence linking asthma exacerbations with viral airway infection and underlying deficiencies in innate immunity and evidence of a synergism between viral infection and allergic mechanisms in increasing risk of exacerbations. Nonadherence to prescribed medication has been identified as a common clinical problem amongst adults and children with difficult-to-control asthma. Appropriate diagnosis, assessment of adherence and other potentially modifiable factors (such as passive or active smoking, ongoing allergen exposure, psychosocial factors) have to be a priority in clinical assessment of all patients with difficult-to-control asthma. Further studies with improved designs and new diagnostic tools are needed to properly characterize (i) the pathophysiology and risk of asthma exacerbations, and (ii) the clinical and pathophysiological heterogeneity of severe asthma.

Severe pneumonia after intravesical BCG instillation in a patient with invasive bladder cancer: case report and literature review.

We present here the case of a 66 year old man with a severe bilateral community acquired pneumonia secondary to dissemination after an intravesical instillation of bacilllus Calmette-Guerin (BCG). Diagnosis was based on positive polymerase chain reaction (PCR) for mycobacterium tuberculosis complex in bronchoalveolar lavage and on the finding on transbronchial biopsy of non necrotising granulomas histopathologically similar to the granulomas found in bladder biopsies. These findings were confirmed using a validated real time PCR assay demonstrating the presence of the BCG genome in transbronchial and bladder biopsies.

Intravenous N-acetylcysteine in respiratory disease with abnormal mucus secretion.

OBJECTIVE: Evidence for the mucolytic and expectorant efficacy of intravenous (IV) N-acetylcysteine (NAC) is limited. This study aimed to evaluate in a large, multicenter, randomized, controlled, subject, and rater-blinded study whether IV NAC is superior to placebo and non-inferior to ambroxol in improving sputum viscosity and expectoration difficulty. PATIENTS AND METHODS: A total of 333 hospitalized subjects from 28 centers in China with respiratory disease (such as acute bronchitis, chronic bronchitis and exacerbations, emphysema, mucoviscidosis, and bronchiectasis) and abnormal mucus secretion were randomly allocated in a 1:1:1 ratio to receive NAC 600 mg, ambroxol hydrochloride 30 mg, or placebo as an IV infusion twice daily for 7 days. Mucolytic and expectorant efficacy was assessed by ordinal categorical 4-point scales and analyzed by stratified and modified Mann-Whitney U statistics. RESULTS: NAC showed consistent and statistically significant superiority to placebo and non-inferiority to ambroxol in change from baseline to day 7 in both sputum viscosity scores [mean (SD) difference 0.24 (0.763), p<0.001 vs. placebo] and expectoration difficulty score [mean (SD) difference 0.29 (0.783), p=0.002 vs. placebo]. Safety findings confirm the good tolerability profile of IV NAC reported from previous small studies, and no new safety concerns were identified. CONCLUSIONS: This is the first large, robust study of the efficacy of IV NAC in respiratory diseases with abnormal mucus secretion. It provides new evidence for IV NAC administration in this indication in clinical situations where the IV route is preferred.

From intensive care to rehabilitation: survey on the satisfaction with care received during prolonged hospitalization for COVID-19 at a northern Italian university hospital.

OBJECTIVE: Investigating the experiences perceived by COVID-19 inpatients is a fundamental research area that is starting to be explored. For this reason, our objective was to provide the first Italian survey on COVID-19 inpatients' satisfaction, obtained through a self-completed questionnaire previously used in a reference study in a UK cohort of COVID-19 patients. SUBJECTS AND METHODS: Hospitalized COVID-19 patients (>20 days) admitted to Ferrara University Hospital who underwent rehabilitation during their hospital stay were invited to complete an anonymous questionnaire. The survey's questions explored the patients' satisfaction with the health services received, and their completion took place approximately one year after hospitalization. Information on sex, number of wards, ICU stays, and hospital discharge dates was collected. RESULTS: Sixty-two completed questionnaires were analyzed. The average overall satisfaction score obtained from the answers indicated by the participants in the tenth question was 4.7 out of 5.0. Very positive responses were observed for information about discharge plans, privacy, management of pain, sleep quality, and feeling of safety. The possibility of being consulted about medications and side effects received a very low satisfaction score. Considering overall satisfaction, no significant differences were noted for sex or ICU stay. The obtained results were almost superimposable to those reported in the cohort of COVID-19 patients of the reference study. CONCLUSIONS: This survey suggested that COVID-19 patients' healthcare satisfaction was high. Nevertheless, some areas must be improved, such as the communication and involvement of the patients in the decision-making of care and the discussion about medications or possible side effects.

Identification by cluster analysis of patients with asthma and nasal symptoms using the MASK-air® mHealth app.

BACKGROUND: The self-reporting of asthma frequently leads to patient misidentification in epidemiological studies. Strategies combining the triangulation of data sources may help to improve the identification of people with asthma. We aimed to combine information from the self-reporting of asthma, medication use and symptoms to identify asthma patterns in the users of an mHealth app. METHODS: We studied MASK-air® users who reported their daily asthma symptoms (assessed by a 0-100 visual analogue scale - "VAS Asthma") at least three times (either in three different months or in any period). K-means cluster analysis methods were applied to identify asthma patterns based on: (i) whether the user self-reported asthma; (ii) whether the user reported asthma medication use and (iii) VAS asthma. Clusters were compared by the number of medications used, VAS asthma levels and Control of Asthma and Allergic Rhinitis Test (CARAT) levels. FINDINGS: We assessed a total of 8,075 MASK-air® users. The main clustering approach resulted in the identification of seven groups. These groups were interpreted as probable: (i) severe/uncontrolled asthma despite treatment (11.9-16.1% of MASK-air® users); (ii) treated and partly-controlled asthma (6.3-9.7%); (iii) treated and controlled asthma (4.6-5.5%); (iv) untreated uncontrolled asthma (18.2-20.5%); (v) untreated partly-controlled asthma (10.1-10.7%); (vi) untreated controlled asthma (6.7-8.5%) and (vii) no evidence of asthma (33.0-40.2%). This classification was validated in a study of 192 patients enrolled by physicians. INTERPRETATION: We identified seven profiles based on the probability of having asthma and on its level of control. mHealth tools are hypothesis-generating and complement classical epidemiological approaches in identifying patients with asthma.

Do small airway abnormalities characterize asthma phenotypes? In search of proof.

The role of small airway abnormalities in asthma pathogenesis has been extensively studied and debated for several decades. However, whether or not small airway abnormalities play a relevant role in specific phenotypes of asthmatic patients and contribute to clinical presentation is largely unknown. In the present review, we evaluated available data on the role of small airways in severe asthma, with a further focus on asthma in smokers and asthma in the elderly. These phenotypes are characterized by a poor response to treatment and they can represent a model of greater small airway impairment. In severe asthmatics, small airway involvement has been shown through evidence of both distal inflammation and of increased air trapping. The few available data on asthmatics who smoke, and elderly asthmatics, similarly suggests that small airway abnormalities contribute to the pathogenesis of the disease. In this perspective, there could be a rationale for specifically assessing small airway impairment in these patients and for clinical studies evaluating whether pharmacological approaches targeting the more peripheral airways result in clinical benefits beyond conventional therapy.

Bronchial glomus tumor mimicking a COPD exacerbation.

We report the case of a glomus tumor originating in the left main bronchus diagnosed in a 79 year old Caucasian man. A glomus tumor is an extremely rare neoplasm in the bronchi with nonspecific clinical features. Bronchoscopy allows the diagnosis through biopsy and subsequent histopathological examination of the tissue and in selected cases may represent a valid alternative to surgery permitting a radical tumor excision.

Rhinovirus induces MUC5AC in a human infection model and in vitro via NF-κB and EGFR pathways.

Rhinovirus (RV) infections are the major cause of asthma exacerbations, the major cause of morbidity and mortality in asthma. MUC5AC is the major mucin produced by bronchial epithelial cells. Whether RV infection upregulates MUC5AC in vivo is unknown and the molecular mechanisms involved are incompletely understood. We investigated RV induction of MUC5AC in vivo and in vitro to identify targets for development of new therapies for asthma exacerbations. RV infection increased MUC5AC release in normal and asthmatic volunteers experimentally infected with RV-16, and in asthmatic, but not normal, subjects, this was related to virus load. Bronchial epithelial cells were confirmed a source of MUC5AC in vivo. RV induction of MUC5AC in bronchial epithelial cells in vitro occurred via nuclear factor-κB-dependent induction of matrix metalloproteinase-mediated transforming growth factor-α release, thereby activating an epidermal growth factor receptor-dependent cascade culminating, via mitogen-activated protein kinase activation, in specificity protein-1 transactivation of the MUC5AC promoter. RV induction of MUC5AC may be an important mechanism in RV-induced asthma exacerbations in vivo. Revealing the complex serial signalling cascade involved identifies targets for development of pharmacologic intervention to treat mucus hypersecretion in RV-induced illness.

Paradoxical effects of cigarette smoke and COPD on SARS-CoV2 infection and disease.

INTRODUCTION: How cigarette smoke (CS) and chronic obstructive pulmonary disease (COPD) affect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and severity is controversial. We investigated the protein and mRNA expression of SARS-CoV-2 entry receptor ACE2 and proteinase TMPRSS2 in lungs from COPD patients and controls, and lung tissue from mice exposed acutely and chronically to CS. Also, we investigated the effects of CS exposure on SARS-CoV-2 infection in human bronchial epithelial cells. METHODS: In Cohort 1, ACE2-positive cells were quantified by immunostaining in FFPE sections from both central and peripheral airways. In Cohort 2, we quantified pulmonary ACE2 protein levels by immunostaining and ELISA, and both ACE2 and TMPRSS2 mRNA levels by RT-qPCR. In C57BL/6 WT mice exposed to air or CS for up to 6 months, pulmonary ACE2 protein levels were quantified by triple immunofluorescence staining and ELISA. The effects of CS exposure on SARS-CoV-2 infection were evaluated after 72hr in vitro infection of Calu-3 cells. After SARS-CoV-2 infection, the cells were fixed for IF staining with dsRNA-specific J2 monoclonal Ab, and cell lysates were harvested for WB of viral nucleocapsid (N) protein. Supernatants (SN) and cytoplasmic lysates were obtained to measure ACE2 levels by ELISA. RESULTS: In both human cohorts, ACE2 protein and mRNA levels were decreased in peripheral airways from COPD patients versus both smoker and NS controls, but similar in central airways. TMPRSS2 levels were similar across groups. Mice exposed to CS had decreased ACE2 protein levels in their bronchial and alveolar epithelia versus air-exposed mice exposed to 3 and 6 months of CS. In Calu3 cells in vitro, CS-treatment abrogated infection to levels below the limit of detection. Similar results were seen with WB for viral N protein, showing peak viral protein synthesis at 72hr. CONCLUSIONS: ACE2 levels were decreased in both bronchial and alveolar epithelial cells from uninfected COPD patients versus controls, and from CS-exposed versus air-exposed mice. CS-pre-treatment did not affect ACE2 levels but potently inhibited SARS-CoV-2 replication in this in vitro model. These findings urge to further investigate the controversial effects of CS and COPD on SARS-CoV2 infection.

Association of increased CCL5 and CXCL7 chemokine expression with neutrophil activation in severe stable COPD.

BACKGROUND: Increased numbers of activated neutrophils have been reported in the bronchial mucosa of patients with stable chronic obstructive pulmonary disease (COPD), particularly in severe disease. OBJECTIVES: To investigate the expression of neutrophilic chemokines and adhesion molecules in bronchial biopsies from patients with stable COPD of different severity (GOLD stages I-IV) compared with age-matched control subjects, smokers with normal lung function and never smokers. METHODS: The expression of CCL5, CXCL1, 5, 6, 7 and 8, CXCR1, CXCR2, CD11b and CD44 was measured in the bronchial mucosa using immunohistochemistry, confocal immunofluorescence, real-time quantitative polymerase chain reaction (RT-QPCR) and Western blotting (WB). RESULTS: The numbers of CCL5+ epithelial cells and CCL5+ and CXCL7+ immunostained cells were increased in the bronchial submucosa of patients with stable severe COPD compared with control never smokers and smokers with normal lung function. This was also confirmed at the level of mRNA expression. The numbers of CCL5+ cells in the submucosa of patients with COPD were 2-15 times higher than any other chemokines. There was no correlation between the number of these cells and the number of neutrophils in the bronchial submucosa. Compared with control smokers, the percentage of neutrophils co-expressing CD11b and CD44 receptors was significantly increased in the submucosa of patients with COPD. CONCLUSION: The increased expression of CCL5 and CXCL7 in the bronchial mucosa of patients with stable COPD, together with an increased expression of extracellular matrix-binding receptors on neutrophils, may be involved in the pathogenesis of COPD.