Short-range interactions between fibrocytes and CD8+ T cells in COPD bronchial inflammatory response.

Bronchi of chronic obstructive pulmonary disease (COPD) are the site of extensive cell infiltration, allowing persistent contact between resident cells and immune cells. Tissue fibrocytes interaction with CD8+ T cells and its consequences were investigated using a combination of in situ, in vitro experiments and mathematical modeling. We show that fibrocytes and CD8+ T cells are found in the vicinity of distal airways and that potential interactions are more frequent in tissues from COPD patients compared to those of control subjects. Increased proximity and clusterization between CD8+ T cells and fibrocytes are associated with altered lung function. Tissular CD8+ T cells from COPD patients promote fibrocyte chemotaxis via the CXCL8-CXCR1/2 axis. Live imaging shows that CD8+ T cells establish short-term interactions with fibrocytes, that trigger CD8+ T cell proliferation in a CD54- and CD86-dependent manner, pro-inflammatory cytokines production, CD8+ T cell cytotoxic activity against bronchial epithelial cells and fibrocyte immunomodulatory properties. We defined a computational model describing these intercellular interactions and calibrated the parameters based on our experimental measurements. We show the model's ability to reproduce histological ex vivo characteristics, and observe an important contribution of fibrocyte-mediated CD8+ T cell proliferation in COPD development. Using the model to test therapeutic scenarios, we predict a recovery time of several years, and the failure of targeting chemotaxis or interacting processes. Altogether, our study reveals that local interactions between fibrocytes and CD8+ T cells could jeopardize the balance between protective immunity and chronic inflammation in the bronchi of COPD patients.

Muscarinic receptor M3 activation promotes fibrocytes contraction.

Fibrocytes are monocyte-derived cells able to differentiate into myofibroblasts-like cells. We have previously shown that they are increased in the bronchi of Chronic Obstructive Pulmonary Disease (COPD) patients and associated to worse lung function. COPD is characterized by irreversible airflow obstruction, partly due to an increased cholinergic environment. Our goal was to investigate muscarinic signalling in COPD fibrocytes. Fibrocytes were isolated from 16 patients with COPD's blood and presence of muscarinic M3 receptor was assessed at the transcriptional and protein levels. Calcium signalling and collagen gels contraction experiments were performed in presence of carbachol (cholinergic agonist) ± tiotropium bromide (antimuscarinic). Expression of M3 receptor was confirmed by Western blot and flow cytometry in differentiated fibrocytes. Immunocytochemistry showed the presence of cytoplasmic and membrane-associated pools of M3. Stimulation with carbachol elicited an intracellular calcium response in 35.7% of fibrocytes. This response was significantly blunted by the presence of tiotropium bromide: 14.6% of responding cells (p < 0.0001). Carbachol induced a significant contraction of fibrocytes embedded in collagen gels (13.6 ± 0.3% versus 2.5 ± 4.1%; p < 0.0001), which was prevented by prior tiotropium bromide addition (4.1 ± 2.7% of gel contraction; p < 0.0001). Finally, M3-expressing fibrocytes were also identified in situ in the peri-bronchial area of COPD patients' lungs, and there was a tendency to an increased density compared to healthy patient's lungs. In conclusion, around 1/3 of COPD patients' fibrocytes express a functional muscarinic M3 receptor. Cholinergic-induced fibrocyte contraction might participate in airway diameter reduction and subsequent increase of airflow resistance in patients with COPD. The inhibition of these processes could participate to the beneficial effects of muscarinic antagonists for COPD treatment.

Second-line lurbinectedin as a new treatment option for small-cell lung cancer: Preliminary results in real-clinical practice.

INTRODUCTION: Few strategies exist for treatment of patients with small-cell lung cancer (SCLC) extended-stage after failure of first-line platinum-based chemotherapy. Lurbinectedin is a novel RNA-polymerase-II inhibitor investigated as a second-line therapy for SCLC. However, its efficacy and safety profile in real clinical practice remain to be determined. OBJECTIVE: To determine the efficacy and safety of lurbinectedin in real-life among patients with SCLC previously treated with first-line platinum-based chemotherapy. METHODS: We retrospectively evaluated patients who received at least one dose of lurbinectedin (3.2 mg/m2 ) between March 2020 and November 2021, in the pulmonary department of Bordeaux University Hospital. Endpoints were time to treatment discontinuation, progression-free survival, overall survival, and safety profile. RESULTS: Thirteen patients were included. The median age was 60 years (range: 42-77), seven (54%) were females, nine (69%) having a performance status of 0-1. Lurbinectedin was given as second-line treatment before platinum rechallenge in four (31%) patients. After a mean follow-up of 4.1 months, the objective response rate (ORR) was 17%. The median time to treatment discontinuation (TTD) was 2.3 months (interquartile range [IQR], 1.2-3.6). The median progression-free survival (PFS) and overall survival (OS) were, respectively, 1.9 (IQR, 0.1.8) and 4.1 (IQR, 2.0-3.5) months. No significant difference regarding TTD, PFS or OS was found in the two groups according to treatment history or according to chemotherapy-free intervall (CMI) 〈1 or 〉1 month. The most common adverse events (AEs) were asthenia, nausea, and anemia in nine (70%) patients. Grade 3 AEs were reported, fatigue, vomiting, nausea, anorexia, and neutropenia. CONCLUSIONS: Lurbinectedin in real clinical practice could have had a lower efficacy than in phase II trial, but a better hematological and bioclinical tolerance than previously reported. Early relapse after platinum-based chemotherapy seems to have a lower response to lurbinectedin.

Clinical impact of STK11 mutation in advanced-stage non-small cell lung cancer.

BACKGROUND: Mutations in STK11/LKB1 gene present a negative impact on tumour immune microenvironment, especially with concomitant activating KRAS mutation. These recent data may explain a decreased response to immunotherapy treatment in STK11 mutant non-small cell lung cancer (NSCLC). OBJECTIVE: The primary objective is to evaluate, in a real-life setting, overall survival (OS) in patients with NSCLC according to the presence of STK11 mutation. The secondary objective is to assess time to treatment failure (TTF) for the first-line chemotherapy or immunotherapy. METHODS: This observational multicentric study was conducted in Nouvelle-Aquitaine (France), for 24 months. Clinical, histopathological and imagery data were collected in each centre while the next-generation sequencing analysis was performed in Bordeaux Hospital University. Patient's data were longitudinally followed from NSCLC diagnosis date to the occurrence of censoring events (therapeutic failure or death, as applicable) or until the study end date. RESULTS: median OS from the first drug administration was significantly longer for STK11wt patients than STK11mut patients (16.2 months [11 - nr] versus 4.7 months [2.5-9.4]; Log-rank test P < 0.001). The Presence of STK11 mutation was significantly associated with shortened OS (RR = 2.26 [1.35-3.79], P = 0.002). First-line TTF was significantly shorter in STK11mut population and the presence of the mutation was significantly associated with an increase in treatment failures (RR = 1.87 [1.21-2.89], P = 0.005). The type of treatment (chemotherapy, immunotherapy) does not influence the amplitude of reduced TTF in patients with STK11mut. CONCLUSION: The presence of STK11 mutation is associated with poor prognosis in NSCLC.

Asthmatic bronchial smooth muscle increases rhinovirus replication within the bronchial epithelium.

Rhinovirus (RV) infection of the bronchial epithelium is implicated in the vast majority of severe asthma exacerbations. Interestingly, the susceptibility of bronchial epithelium to RV infection is increased in persons with asthma. Bronchial smooth muscle (BSM) remodeling is an important feature of severe asthma pathophysiology, and its reduction using bronchial thermoplasty has been associated with a significant decrease in the exacerbation rate. We hypothesized that asthmatic BSM can play a role in RV infection of the bronchial epithelium. Using an original co-culture model between bronchial epithelium and BSM cells, we show that asthmatic BSM cells increase RV replication in bronchial epithelium following RV infection. These findings are related to the increased production of CCL20 by asthmatic BSM cells. Moreover, we demonstrate an original downregulation of the activity of the epithelial protein kinase RNA-activated (PKR) antiviral pathway. Finally, we identify a direct bottom-up effect of asthmatic BSM cells on bronchial epithelium susceptibility to RV infection.

De-labelling severe asthma diagnosis: the challenge of DIPNECH.

DIPNECH is a differential diagnosis of severe asthma with no specific biomarkers. Chronic cough and multiple nodules on CT should prompt clinicians to consider this diagnosis. Differentiating DIPNECH from severe asthma remains crucial. https://bit.ly/3mmFbQn.

Rhinovirus infection of bronchial epithelium induces specific bronchial smooth muscle cell migration of severe asthmatic patients.

BACKGROUND: Patients with severe asthma show an increase in both exacerbation frequency and bronchial smooth muscle (BSM) mass. Rhinovirus (RV) infection of the bronchial epithelium (BE) is the main trigger of asthma exacerbations. Histological analysis of biopsies shows that a close connection between BE and hypertrophic BSM is a criterion for severity of asthma. OBJECTIVE: We hypothesized that RV infection of BE specifically increases BSM-cell migration from patients with asthma. METHODS: Serum samples, biopsies, or BSM cells were obtained from 86 patients with severe asthma and 31 subjects without asthma. BE cells from subjects without asthma were cultured in an air-liquid interface and exposed to RV-16. Migration of BSM cells was assessed in response to BE supernatant using chemotaxis assays. Chemokine concentrations were analyzed by transcriptomics and ELISAs. Immunocytochemistry, western blotting, and flow cytometry were used to quantify CXCR3 isoform distribution. CXCR3 downstream signaling pathways were assessed by calcium imaging and western blots. RESULTS: BSM cells from patients with severe asthma specifically migrated toward RV-infected BE, whereas those from subjects without asthma did not. This specific migration is driven by BE C-X-C motif chemokine ligand 10, which was increased in vitro in response to RV infection as well as in vivo in serum from exacerbating patients with severe asthma. The mechanism is related to both decreased expression and activation of the CXCR3-B-specific isoform in BSM cells from those with severe asthma. CONCLUSIONS: We have demonstrated a novel mechanism of BSM remodeling in patients with severe asthma following RV exacerbation. This study highlights the C-X-C motif chemokine ligand 10/CXCR3-A axis as a potential therapeutic target in severe asthma.

Clinical pharmacology: Current innovations and future challenges.

Clinical pharmacology is the study of drugs in humans, from first-in-human studies to randomized controlled trials (RCTs) and benefit-risk ratio assessment in large populations. The objective of this review is to present the recent innovations that may revolutionize the development of drugs in the future. On behalf of the French Society of Pharmacology and Therapeutics, we provide recommendations to address those future challenges in clinical pharmacology. Whatever the future will be, robust preliminary data on drug mechanism of action and rigorous study design will remain crucial prior to the start of pharmacological studies in human. At the present time, RCTs remain the gold standard to evaluate the efficacy of human drugs, although alternative designs (pragmatic trials, platform trials, etc.) are emerging. Innovations in healthy volunteers' studies and the contribution of new technologies such as artificial intelligence, machine learning, and internet-based trials have the potential to improve drug development. In the field of precision medicine, new disease phenotypes and endotypes will probably help to identify new pharmacological targets, responders to therapies, and patients at risk for drug adverse events. In such a moving landscape, the development of translational research through academic and private partnership, transparent sharing of clinical trial data and enhanced interactions between drug experts, patients, and the general public are priority areas for action.

Crucial role of fatty acid oxidation in asthmatic bronchial smooth muscle remodelling.

BACKGROUND: Bronchial smooth muscle (BSM) remodelling in asthma is related to an increased mitochondrial biogenesis and enhanced BSM cell proliferation in asthma. Since mitochondria produce the highest levels of cellular energy and fatty acid ß-oxidation is the most powerful way to produce ATP, we hypothesised that, in asthmatic BSM cells, energetic metabolism is shifted towards the ß-oxidation of fatty acids. OBJECTIVES: We aimed to characterise BSM cell metabolism in asthma both in vitro and ex vivo to identify a novel target for reducing BSM cell proliferation. METHODS: 21 asthmatic and 31 non-asthmatic patients were enrolled. We used metabolomic and proteomic approaches to study BSM cells. Oxidative stress, ATP synthesis, fatty acid endocytosis, metabolite production, metabolic capabilities, mitochondrial networks, cell proliferation and apoptosis were assessed on BSM cells. Fatty acid content was assessed in vivo using matrix-assisted laser desorption/ionisation spectrometry imaging. RESULTS: Asthmatic BSM cells were characterised by an increased rate of mitochondrial respiration with a stimulated ATP production and mitochondrial ß-oxidation. Fatty acid consumption was increased in asthmatic BSM both in vitro and ex vivo. Proteome remodelling of asthmatic BSM occurred via two canonical mitochondrial pathways. The levels of carnitine palmitoyl transferase (CPT)2 and low-density lipoprotein (LDL) receptor, which internalise fatty acids through mitochondrial and cell membranes, respectively, were both increased in asthmatic BSM cells. Blocking CPT2 or LDL receptor drastically and specifically reduced asthmatic BSM cell proliferation. CONCLUSION: This study demonstrates a metabolic switch towards mitochondrial ß-oxidation in asthmatic BSM and identifies fatty acid metabolism as a new key target to reduce BSM remodelling in asthma.

Type 2-high asthma is associated with a specific indoor mycobiome and microbiome.

BACKGROUND: The links between microbial environmental exposures and asthma are well documented, but no study has combined deep sequencing results from pulmonary and indoor microbiomes of patients with asthma with spirometry, clinical, and endotype parameters. OBJECTIVE: The goal of this study was to investigate the links between indoor microbial exposures and pulmonary microbial communities and to document the role of microbial exposures on inflammatory and clinical outcomes of patients with severe asthma (SA). METHODS: A total of 55 patients with SA from the national Cohort of Bronchial Obstruction and Asthma cohort were enrolled for analyzing their indoor microbial flora through the use of electrostatic dust collectors (EDCs). Among these patients, 22 were able to produce sputum during "stable" or pulmonary "exacerbation" periods and had complete pairs of EDC and sputum samples, both collected and analyzed. We used amplicon targeted metagenomics to compare microbial communities from EDC and sputum samples of patients according to type 2 (T2)-asthma endotypes. RESULTS: Compared with patients with T2-low SA, patients with T2-high SA exhibited an increase in bacterial α-diversity and a decrease in fungal α-diversity of their indoor microbial florae, the latter being significantly correlated with fraction of exhaled nitric oxide levels. The ß-diversity of the EDC mycobiome clustered significantly according to T2 endotypes. Moreover, the proportion of fungal taxa in common between the sputum and EDC samples was significantly higher when patients exhibited acute exacerbation. CONCLUSION: These results illustrated, for the first time, a potential association between the indoor mycobiome and clinical features of patients with SA, which should renew interest in deciphering the interactions between indoor environment, fungi, and host in asthma.

Factors associated with serious vehicular accidents: A cross-sectional study in hospital emergency rooms.

AIMS: Pictograms on medicine boxes warn of potential drug-related driving hazard; we studied their association with serious accidents. METHODS: Prospective study in emergency departments of the hospitals in Bordeaux and Périgueux (France), of drivers with serious (admitted at least 24 hours) or nonserious vehicular accidents. Minors, passengers, pedestrians or subjects incapable of answering an interview were excluded. Interviews ascertained driver and accident characteristics, use of drugs with or without pictograms, use of alcohol and abuse substances, sleepiness, distractions, and mind wandering at the time of the accident, RESULTS: Between 18 October 2016 and 26 December 2018, 1200 of the 6212 drivers admitted to the hospital emergency rooms, 741 nonserious, 459 serious, were interviewed. Serious accidents were associated with male sex (odds ratio 1.89, 95% confidence interval [1.36-2.64]), age above 60 years (3.64 [2.21-6.00]), driving on local roads (3.34 [2.34-4.76]), driving a motorcycle (3.39 [2.29-5.00]), having drunk alcohol within 6 hours (2.89 [1.85-4.51]) and using a drug with a pictogram during the 24 hours previous to the accident (1.57 [1.06-2.32]). From 207 police reports, 101 drivers were not responsible, and 106 were responsible, associated with age below 40 years, driving in overcast or rainy weather (2.62 [1.29-5.33]), on local roads (3.89 [1.90-7.95]), and use of at least 1 pictogram drug in the previous week (3.12 [1.31-7.41]). CONCLUSION: The known risks of alcohol and pictogram drugs, of riding motorcycles and using local roads were confirmed. As measured, behavioural sleepiness did not predict accidents.

Effectiveness and safety of dupilumab for the treatment of severe asthma in a real-life French multi-centre adult cohort.

BACKGROUND: Dupilumab is a monoclonal anti-IL-4Rα antibody developed for the treatment of severe asthma (SA). An early access programme for dupilumab was opened in France in SA patients experiencing unacceptable steroids side-effects and/or life-threatening exacerbations. OBJECTIVE: To assess changes in asthma control between baseline and 12 months of treatment. METHODS: Multi-centre (n = 13) retrospective real-life cohort study. This study is registered on ClinicalTrials.gov (NCT04022447). RESULTS: Overall, 64 patients with SA (median age 51, interquartile range [44-61]; 53% females) received dupilumab as add-on therapy to maximal standard of care; and 76% were on oral daily steroids at baseline. After 12 months, median asthma control test score improved from 14 [7-16] to 22 [17-24] (P < .001); median forced expiratory volume in 1 seconds increased from 58% [47-75] to 68% [58-88] (P = .001); and daily prednisone dose was reduced from 20 [10-30] to 5 [0-7] mg/d (P < .001). Annual exacerbations decreased from 4 [2-7] to 1 [0-2] (P < .001). Hypereosinophilia ≥1500/mm3 was observed at least once during follow-up in 16 patients (25%), persisting after 6 months in 8 (14%) of them. Increase in blood eosinophil count did not modify the clinical response during the study period. Injection-site reaction was the most common side effect (14%). Three deaths were observed, none related to treatment by investigators. CONCLUSION & CLINICAL RELEVANCE: In this first real-life cohort study of predominantly steroid-dependent SA, dupilumab significantly improved asthma control and lung function and reduced oral steroids use and exacerbations rate. Despite limitations due to the retrospective study, these results are consistent with controlled trials efficacy data. Further studies are required to assess the clinical significance and long-term prognosis of sustained dupilumab-induced hypereosinophilia.

Assessing pulmonary hypertension in COPD. Is there a role for computed tomography?

Pulmonary hypertension (PH) is a common complication of chronic obstructive pulmonary disease (COPD) and is associated with increased morbidity and mortality. Reference standard method to diagnose PH is right heart catheterization. Several non-invasive imaging techniques have been employed in the detection of PH. Among them, computed tomography (CT) is the most commonly used for phenotyping and detecting complications of COPD. Several CT findings have also been described in patients with severe PH. Nevertheless, CT analysis is currently based on visual findings which can lead to reproducibility failure. Therefore, there is a need for quantification in order to assess objective criteria. In this review, progresses in automated analyses of CT parameters and their values in predicting PH and COPD outcomes are presented.

Fibrocyte accumulation in the airway walls of COPD patients.

The remodelling mechanism and cellular players causing persistent airflow limitation in COPD remain largely elusive. We have recently demonstrated that circulating fibrocytes, a rare population of fibroblast-like cells produced by the bone marrow stroma, are increased in COPD patients during an exacerbation. We aimed to quantify fibrocyte density in situ in bronchial specimens from both control subjects and COPD patients, to define associations with relevant clinical, functional and computed tomography (CT) parameters, and to investigate the effect of the epithelial microenvironment on fibrocyte survival in vitro ("Fibrochir" study).A total of 17 COPD patients and 25 control subjects, all requiring thoracic surgery, were recruited. Using co-immunostaining and image analysis, we identified CD45+ FSP1+ cells as tissue fibrocytes, and quantified their density in distal and proximal bronchial specimens. Fibrocytes, cultured from the blood samples of six COPD patients, were exposed to primary bronchial epithelial cell secretions from control subjects or COPD patients.We demonstrate that fibrocytes are increased in both distal and proximal tissue specimens of COPD patients. The density of fibrocytes is negatively correlated with lung function parameters and positively correlated with bronchial wall thickness as assessed by CT scan. A high density of distal bronchial fibrocytes predicts the presence of COPD with a sensitivity of 83% and a specificity of 70%. Exposure of fibrocytes to COPD epithelial cell supernatant favours cell survival.Our results thus demonstrate an increased density of fibrocytes within the bronchi of COPD patients, which may be promoted by epithelial-derived survival-mediating factors.