U-BIOPRED is a European Union consortium of 20 academic institutions, 11 pharmaceutical companies and six patient organisations with the objective of improving the understanding of asthma disease mechanisms using a systems biology approach.This cross-sectional assessment of adults with severe asthma, mild/moderate asthma and healthy controls from 11 European countries consisted of analyses of patient-reported outcomes, lung function, blood and airway inflammatory measurements.Patients with severe asthma (nonsmokers, n=311; smokers/ex-smokers, n=110) had more symptoms and exacerbations compared to patients with mild/moderate disease (n=88) (2.5 exacerbations versus 0.4 in the preceding 12 months; p<0.001), with worse quality of life, and higher levels of anxiety and depression. They also had a higher incidence of nasal polyps and gastro-oesophageal reflux with lower lung function. Sputum eosinophil count was higher in severe asthma compared to mild/moderate asthma (median count 2.99% versus 1.05%; p=0.004) despite treatment with higher doses of inhaled and/or oral corticosteroids.Consistent with other severe asthma cohorts, U-BIOPRED is characterised by poor symptom control, increased comorbidity and airway inflammation, despite high levels of treatment. It is well suited to identify asthma phenotypes using the array of "omic" datasets that are at the core of this systems medicine approach. @ERSpublications Severe asthma results in more airway inflammation, worse symptoms and lower lung function, despite increased therapy http://ow.ly/QznR3

BackgroundThe coronavirus infectious disease (COVID-19) pandemic is an ongoing global health care challenge. Up to one third of hospitalised patients develop severe pulmonary complications and ARDS. Pulmonary outcomes following COVID-19 are unknown.MethodsThe Swiss COVID-19 lung study is a multicentre prospective cohort investigating pulmonary sequela of COVID-19. We report on initial follow-up 4 months after mild/moderate or severe/critical COVID-19 according to the WHO severity classification.Results113 COVID-19 survivors were included (mild/moderate 47, severe/critical 66). We confirmed several comorbidities as risk factors for severe/critical disease. Severe/critical disease was associated with impaired pulmonary function, i.e. diffusing capacity (DLCO) %-predicted, reduced 6-MWD, and exercise-induced oxygen desaturation. After adjustment for potential confounding by age, sex, and BMI, patients after severe/critical COVID-19 had a 20.9 (95% CI 12.4–29.4, p=0.01) lower DLCO %-predicted at follow up. DLCO %-predicted was the strongest independent factor associated with previous severe/critical disease when age, sex, BMI, 6MWD, and minimal SpO2 at exercise, were included in the multivariable model (adjusted odds ratio [OR] per 10%-predicted 0.59 [95% CI 0. 37–0.87], p=0.01). Mosaic hypoattenuation on chest computed tomography at follow-up was significantly associated with previous severe/critical COVID-19 including adjustment for age and sex (adjusted OR 11.7 [95%CI 1.7–239), p=0.03).ConclusionsFour months after SARS CoV-2 infection, severe/critical COVID-19 was associated with significant functional and radiological abnormalities, potentially due to small airway and lung parenchymal disease. A systematic follow-up for survivors needs to be evaluated to optimise care for patients recovering from COVID-19.

We report a lung-on-a-chip array that mimics the pulmonary parenchymal environment, including the thin alveolar barrier and the three-dimensional cyclic strain induced by breathing movements. The micro-diaphragm used to stretch the alveolar barrier is inspired by the in vivo diaphragm, the main muscle responsible for inspiration. The design of this device aims not only at best reproducing the in vivo conditions found in the lung parenchyma but also at making the device robust and its handling easy. An innovative concept, based on the reversible bonding of the device, is presented that enables accurate control of the concentration of cells cultured on the membrane by easily accessing both sides of the membranes. The functionality of the alveolar barrier could be restored by co-culturing epithelial and endothelial cells that form tight monolayers on each side of a thin, porous and stretchable membrane. We showed that cyclic stretch significantly affects the permeability properties of epithelial cell layers. Furthermore, we also demonstrated that the strain influences the metabolic activity and the cytokine secretion of primary human pulmonary alveolar epithelial cells obtained from patients. These results demonstrate the potential of this device and confirm the importance of the mechanical strain induced by breathing in pulmonary research.

Clustering based on clinicophysiologic parameters yielded 4 stable and reproducible clusters that associate with different pathobiological pathways.

Interleukin-8 (IL-8), a pro-inflammatory protein, has been shown by nuclear magnetic resonance (NMR) and x-ray techniques to exist as a homodimer. An IL-8 analog was chemically synthesized, with the amide nitrogen of leucine-25 methylated to selectivity block formation of hydrogen bonds between monomers and thereby prevent dimerization. This analog was shown to be a monomer, as assessed by analytical ultracentrifugation and NMR. Nevertheless, it was equivalent to IL-8 in assays of neutrophil activation, which indicates that the monomer is a functional form of IL-8.

SummaryCC chemokines constitute a novel class of cytokines that attract and activate monocytes and lymphocytes, as well as basophil and eosinophil lenkocytes, with distinct target cell profiles, and are believed to be involved in the regulation of different types of inflammation. The action of the recently identified monocyte chemotactic protein 3 (MCP-3) on human basophil and eosinophil function was studied and compared with that of other CC chemokines. In basophils, MCP-3, MCP-1, P.ANTES, and macrophage inflammatory protein (MIP)-loe all induced cyrosolic-frce calcium concentration ([Ca 2 + ]i) changes and, with different efticacies, chemotaxis (R_ANTES --MCP-3 >> MCP-1 > MIP-lc~), histamine release (MCP-1 = MCP-3 >> P.ANTES > MIPlc 0' and leukotriene C4 formation, after IL-3 pretreatment (MCP-1 = MCP-3 >> RANTES > MIP-loe). Thus, MCP-3 was as effective as MCP-1 as an inducer of mediator release, and as effective as R.ANTES as a stimulus of basophil migration. In contrast to MCP-1, MCP-3 was also a stimulus for eosinophils, and induced [Ca2+]i changes and chemotaxis as effectively as R.ANTES, which is the most potent chemotactic cytokine for these cells. Desensitization of the transient changes in [Ca2+]i was used tO assess receptor usage. In basophils, stimulation with MCP-3 prevented responsiveness to MCP-1 and R.ANTES, but not to MIP-loe. No single CC chemokine (except for MCP-3 itse~ affected the response to MCP-3, however, which was prevented only when the cells were prestimulated with both MCP-1 and R.ANTES. In eosinophils, by contrast, cross-desensitization between R.ANTES and MCP-3 was obtained. P.ANTES and to a lesser extent MCP-3 also desensitized eosinophils toward MIP-lce. The desensitization data suggest the existence of three chemokine receptors: (a) a MCP-1 receptor expressed on basophils but not eosinophils that is activated by MCP-1 and MCP-3; (b) a RANTES receptor in basophils and eosinophils that is activated by R.ANTES and MCP-3; and (c) a MIP-lce receptor that is activated by MIP-loe, R.ANTES and, more weakly, by MCP-3. This study shows that MCP-3 combines the properties of R.ANTES, a powerful chemoattractant, and MCP-1, a highly effective stimulus of mediator release, and thus has a particularly broad range of activities toward both human basophil and eosinophil lenkocytes.A few years ago, chemotactic cyt0kines (now termed chemokines) were viewed as attractants for neutrophils (CXC chemokines) or mononuclear cells (CC chemokines). It was then found that IL-8 induces histamine and lenkotriene (LT)tC,4 release from IL-3-primed human blood basophils (1, 2) via GTP-binding protein-coupled receptors (3). Later studies showed that some CC chemokines activate basophil as well as eosinophil lenkocytes, suggesting that they may function 1Abbra, iations used in this paper: [Ca2+]i, cytosolic-free calcium concentration; LT, leukotriene; MCP, monocyte chemotactic protein; MIP, macrophage inflammatory protein.as mediators in allergic conditions and parasitic infestations. Several laboratories reported...

Background:The alveolar compartment is a procoagulant antifibrinolytic environment in acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS). A study was undertaken to test the hypothesis that the alveolar epithelium can initiate intra-alveolar coagulation by expressing active tissue factor (TF). Methods: Using an in vitro cell surface TF assay and TF ELISA, the activity and production of TF in cultured alveolar epithelial (A549) cells following exposure to cytomix (tumour necrosis factor a, interleukin 1b and interferon c) was measured. TF gene transcription was measured by semi-quantitative reverse-transcription PCR. Immunohistochemistry for TF was performed on lung sections from patients with ARDS and controls. TF protein levels were measured by ELISA in undiluted pulmonary oedema fluid from patients with ALI/ARDS and compared with control patients with hydrostatic pulmonary oedema. Results: TF activity, mRNA and protein levels increased in A549 cells after stimulation with cytomix. Increased TF activity was also seen in A549 cells following incubation with pulmonary oedema fluid from patients with ALI/ARDS. Immunohistochemistry for TF in human lung tissue from patients with ARDS showed prominent TF staining in alveolar epithelial cells as well as intra-alveolar macrophages and hyaline membranes. TF antigen levels in oedema fluid (median 37 113 (IQR 14 956-73 525) pg/ml) were significantly higher than in plasma (median 336 (IQR 165-669) pg/ml, p,0.001) in patients with ALI/ARDS, and TF procoagulant activity in oedema fluid was much higher than in plasma of these patients. Higher plasma levels were associated with mortality. Conclusions: The alveolar epithelium is capable of modulating intra-alveolar coagulation through upregulation of TF following exposure to inflammatory stimuli and may contribute to intra-alveolar fibrin deposition in ARDS.

Virus-associated pulmonary exacerbations, often associated with rhinoviruses (RVs), contribute to cystic fibrosis (CF) morbidity. Currently, there are only a few therapeutic options to treat virus-induced CF pulmonary exacerbations. The macrolide antibiotic azithromycin has antiviral properties in human bronchial epithelial cells. We investigated the potential of azithromycin to induce antiviral mechanisms in CF bronchial epithelial cells.Primary bronchial epithelial cells from CF and control children were infected with RV after azithromycin pre-treatment. Viral RNA, interferon (IFN), IFN-stimulated gene and pattern recognition receptor expression were measured by real-time quantitative PCR. Live virus shedding was assessed by assaying the 50% tissue culture infective dose. Pro-inflammatory cytokine and IFN-β production were evaluated by ELISA. Cell death was investigated by flow cytometry.RV replication was increased in CF compared with control cells. Azithromycin reduced RV replication seven-fold in CF cells without inducing cell death. Furthermore, azithromycin increased RV-induced pattern recognition receptor, IFN and IFN-stimulated gene mRNA levels. While stimulating antiviral responses, azithromycin did not prevent virus-induced pro-inflammatory responses.Azithromycin pre-treatment reduces RV replication in CF bronchial epithelial cells, possibly through the amplification of the antiviral response mediated by the IFN pathway. Clinical studies are needed to elucidate the potential of azithromycin in the management and prevention of RV-induced CF pulmonary exacerbations. @ERSpublications Azithromycin reduces rhinovirus load in CF bronchial cells, possibly through the induction of the interferon pathway