Voices of conference attendees: how should future hybrid conferences be designed?

BACKGROUND

With conference attendees having expressed preference for hybrid meeting formats (containing both in-person and virtual components), organisers are challenged to find the best combination of events for academic meetings. Better understanding what attendees prioritise in a hybrid conference should allow better planning and need fulfilment.

METHODS

An online survey with closed and open-ended questions was distributed to registrants of an international virtual conference. Responses were then submitted to descriptive statistical analysis and directed content analysis.

RESULTS

823 surveys (Response Rate = 4.9%) were received. Of the 813 who expressed a preference, 56.9% (N = 463) desired hybrid conference formats in the future, 32.0% (N = 260) preferred in-person conferences and 11.1% (N = 90) preferred virtual conferences. Presuming a hybrid meeting could be adopted, 67.4% (461/684) preferred that virtual sessions take place both during the in-person conference and be spread throughout the year. To optimise in-person components of hybrid conferences, recommendations received from 503 respondents included: prioritising clinical skills sessions (26.2%, N = 132), live international expert presentations and discussions (15.7%, N = 79) and interaction between delegates (13.5%, N = 68). To optimise virtual components, recommendations received from 486 respondents included: prioritising a live streaming platform with international experts' presentations and discussions (24.3%, N = 118), clinical case discussions (19.8%, N = 96) and clinical update sessions (10.1%, N = 49).

CONCLUSIONS

Attendees envision hybrid conferences in which organisers can enable the vital interaction between individuals during an in-person component (e.g., networking, viewing and improving clinical skills) while accessing virtual content at their convenience (e.g., online expert presentations with latest advancements, clinical case discussions and debates). Having accessible virtual sessions throughout the year, as well as live streaming during the in-person component of hybrid conferences, allows for opportunity to prolong learning beyond the conference days.

Objective sputum colour assessment and clinical outcomes in bronchiectasis: data from the European Bronchiectasis Registry (EMBARC)

BACKGROUND

A validated 4-point sputum colour chart can be used to objectively evaluate the levels of airway inflammation in bronchiectasis patients. In the European Bronchiectasis Registry (EMBARC), we tested whether sputum colour would be associated with disease severity and clinical outcomes.

METHODS

We used a prospective, observational registry of adults with bronchiectasis conducted in 31 countries. Patients who did not produce spontaneous sputum were excluded from the analysis. The Murray sputum colour chart was used at baseline and at follow-up visits. Key outcomes were frequency of exacerbations, hospitalisations for severe exacerbations and mortality during up to 5-year follow-up.

RESULTS

13 484 patients were included in the analysis. More purulent sputum was associated with lower forced expiratory volume in 1 s (FEV1), worse quality of life, greater bacterial infection and a higher bronchiectasis severity index. Sputum colour was strongly associated with the risk of future exacerbations during follow-up. Compared to patients with mucoid sputum (reference group), patients with mucopurulent sputum experienced significantly more exacerbations (incident rate ratio (IRR) 1.29, 95% CI 1.22-1.38; p<0.0001), while the rates were even higher for patients with purulent (IRR 1.55, 95% CI 1.44-1.67; p<0.0001) and severely purulent sputum (IRR 1.91, 95% CI 1.52-2.39; p<0.0001). Hospitalisations for severe exacerbations were also associated with increasing sputum colour with rate ratios, compared to patients with mucoid sputum, of 1.41 (95% CI 1.29-1.56; p<0.0001), 1.98 (95% CI 1.77-2.21; p<0.0001) and 3.05 (95% CI 2.25-4.14; p<0.0001) for mucopurulent, purulent and severely purulent sputum, respectively. Mortality was significantly increased with increasing sputum purulence, hazard ratio 1.12 (95% CI 1.01-1.24; p=0.027), for each increment in sputum purulence.

CONCLUSION

Sputum colour is a simple marker of disease severity and future risk of exacerbations, severe exacerbations and mortality in patients with bronchiectasis.

The relationship between periodic limb movement during sleep and dyslipidaemia in patients with obstructive sleep apnea

Periodic limb movements during sleep and obstructive sleep apnea are both associated with increased sympathetic tone, and have been proposed as risk factors for heart diseases and, in particular, cardiovascular disease. As sympathetic system activation may lead to dyslipidaemia, periodic limb movements during sleep could be an additional risk factor for cardiovascular disease in patients with obstructive sleep apnea. The aim of the study was to determine whether the presence of periodic limb movements during sleep affects serum lipid levels in obstructive sleep apnea. Total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, non- high-density lipoprotein cholesterol and triglyceride levels were investigated in 4138 patients with obstructive sleep apnea in the European Sleep Apnea Database (ESADA) cohort, divided into those with periodic limb movements during sleep index ≥ 15 per hr (n = 628) and controls (n = 3510). ANCOVA adjusted for age, sex, body mass index, apnea-hypopnea index, alcohol intake, smoking status, diabetes, insomnia and study site was used to assess differences in lipids between periodic limb movements during sleep and controls. Patients with periodic limb movements during sleep (24% female, 54.4 ± 12.1 years, body mass index 31.9 ± 5.8 kg m-2 , apnea-hypopnea index 36.7 ± 25.4 per hr) had higher triglyceride (1.81 ± 1.04 versus 1.69 ± 0.90 mmol L-1 , p = 0.002) and lower high-density lipoprotein cholesterol (1.19 ± 0.34 versus 1.24 ± 0.37 mmol L-1 , p = 0.002) levels, whilst there was no difference in either total cholesterol (4.98 ± 1.10 versus 4.94 ± 1.07 mmol L-1 ), low-density lipoprotein cholesterol (3.04 ± 0.96 versus 2.98 ± 0.98 mmol L-1 ) or non- high-density lipoprotein cholesterol (3.78 ± 1.10 versus 3.70 ± 1.05 mmol L-1 ) concentrations (all p > 0.05). The results remained unchanged after most sensitivity analyses. Patients with obstructive sleep apnea with periodic limb movements during sleep had more prevalent cardiovascular disease (11% versus 6%, p < 0.01). Periodic limb movements during sleep in obstructive sleep apnea is associated with dyslipidaemia independently of important confounders. Our results highlight periodic limb movements during sleep as an additional risk factor for cardiovascular disease in obstructive sleep apnea.

Haemodynamic phenotypes of pulmonary hypertension associated with left heart disease: a moving target

Shifting haemodynamic definitions impact prevalence of CpcPH in PH associated with left heart disease. Diastolic pressure gradient ≥7 mmHg and pulmonary vascular resistance >5 WU predict pulmonary vascular disease similarly well. https://bit.ly/3OEG5pw

One size does not fit all: Lysosomes exist in biochemically and functionally distinct states

Single-organelle resolution approaches have the potential to advance our knowledge of the heterogeneity of lysosome function. Challenging population-based models, we propose a "lysosome states" concept that links single lysosomes to function.

Eradication treatment for Pseudomonas aeruginosa infection in adults with bronchiectasis: a systematic review and meta-analysis

INTRODUCTION

Pseudomonas aeruginosa is the most commonly isolated pathogen in bronchiectasis and is associated with worse outcomes. Eradication treatment is recommended by guidelines, but the evidence base is limited. The expected success rate of eradication in clinical practice is not known.

METHODS

We conducted a systematic review and meta-analysis according to Meta-Analysis of Observational Studies in Epidemiology guidelines. PubMed, Embase, the Cochrane Database of Systematic Reviews and Clinicaltrials.gov were searched for studies investigating P. aeruginosa eradication treatment using antibiotics (systemic or inhaled) in patients with bronchiectasis. The primary outcome was the percentage of patients negative for P. aeruginosa at 12 months after eradication treatment. Cystic fibrosis was excluded.

RESULTS

Six observational studies including 289 patients were included in the meta-analysis. Our meta-analysis found a 12-month P. aeruginosa eradication rate of 40% (95% CI 34-45%; p<0.00001), with no significant heterogeneity (I2=0%). Combined systemic and inhaled antibiotic treatment was associated with a higher eradication rate (48%, 95% CI 41-55%) than systemic antibiotics alone (27%, 13-45%).

CONCLUSION

Eradication treatment in bronchiectasis results in eradication of P. aeruginosa from sputum in ∼40% of cases at 12 months. Combined systemic and inhaled antibiotics achieve higher eradication rates than systemic antibiotics alone.

Overnight desaturation in interstitial lung diseases: links to pulmonary vasculopathy and mortality

Background

Overnight desaturation predicts poor prognosis across interstitial lung diseases (ILDs). The aim of the present study was to investigate whether nocturnal desaturation is associated with pulmonary vasculopathy and mortality.

Methods

A retrospective single centre study of 397 new ILD patients was carried out including patients with idiopathic pulmonary fibrosis (IPF) (n=107) and patients with non-IPF fibrotic ILD (n=290). This is the largest study to date of the effect of significant nocturnal desaturation (SND) (≥10% of total sleep time with oxygen saturation ≤90% measured by pulse oximetry).

Results

The prevalence of SND was 28/107 (26.2%) in IPF and 80/290 (27.6%) in non-IPF ILD. The prevalence of SND was higher in non-IPF ILDs than in IPF (p=0.025) in multivariate analysis. SND was associated with noninvasive markers of pulmonary hypertension (PH): tricuspid regurgitation velocity (TRV) (p<0.0001), brain natriuretic peptide (p<0.007), carbon monoxide transfer coefficient (p<0.0001), A-a gradient (p<0.0001), desaturation >4% in 6-min walking test (p<0.03) and pulmonary artery diameter (p<0.005). SND was independently associated with high echocardiographic PH probability in the entire cohort (OR 2.865, 95% CI 1.486-5.522, p<0.002) and in non-IPF fibrotic ILD (OR 3.492, 95% CI 1.597-7.636, p<0.002) in multivariate analysis. In multivariate analysis, SND was associated with mortality in the entire cohort (OR 1.734, 95% CI 1.202-2.499, p=0.003) and in IPF (OR 1.908, 95% CI 1.120-3.251, p=0.017) and non-IPF fibrotic ILD (OR 1.663, 95% CI 1.000-2.819, p=0.041). Separate models with exclusion of each one of the diagnostic subgroups showed that no subgroup was responsible for this finding in non-IPF ILDs. SND was a stronger marker of 5-year mortality than markers of PH.

Conclusion

SND was associated with high echocardiographic probability and mortality and was a stronger predictor of mortality in IPF and non-IPF ILDs grouped together to power the study.

A BEAT-PCD consensus statement: a core outcome set for pulmonary disease interventions in primary ciliary dyskinesia

Background

Consistent use of reliable and clinically appropriate outcome measures is a priority for clinical trials, with clear definitions to allow comparability. We aimed to develop a core outcome set (COS) for pulmonary disease interventions in primary ciliary dyskinesia (PCD).

Methods

A multidisciplinary international PCD expert panel was set up. A list of outcomes was created based on published literature. Using a modified three-round e-Delphi technique, the panel was asked to decide on relevant end-points related to pulmonary disease interventions and how they should be reported. First, inclusion of an outcome in the COS was determined. Second, the minimum information that should be reported per outcome. The third round finalised statements. Consensus was defined as ≥80% agreement among experts.

Results

During the first round, experts reached consensus on four out of 24 outcomes to be included in the COS. Five additional outcomes were discussed in subsequent rounds for their use in different subsettings. Consensus on standardised methods of reporting for the COS was reached. Spirometry, health-related quality-of-life scores, microbiology and exacerbations were included in the final COS.

Conclusion

This expert consensus resulted in a COS for clinical trials on pulmonary health among people with PCD.

Inflammatory Molecular Endotypes in Bronchiectasis: A European Multicenter Cohort Study

Rationale: Although inflammation and infection are key disease drivers in bronchiectasis, few studies have integrated host inflammatory and microbiome data to guide precision medicine. Objectives: To identify clusters among patients with bronchiectasis on the basis of inflammatory markers and to assess the association between inflammatory endotypes, microbiome characteristics, and exacerbation risk. Methods: Patients with stable bronchiectasis were enrolled at three European centers, and cluster analysis was used to stratify the patients according to the levels of 33 sputum and serum inflammatory markers. Clusters were compared in terms of microbiome composition (16S ribosomal RNA sequencing) and exacerbation risk over a 12-month follow-up. Measurements and Main Results: A total of 199 patients were enrolled (109 [54.8%] female; median age, 69 yr). Four clusters of patients were defined according to their inflammatory profiles: cluster 1, milder neutrophilic inflammation; cluster 2, mixed-neutrophilic and type 2; cluster 3, most severe neutrophilic; and cluster 4, mixed-epithelial and type 2. Lower microbiome diversity was associated with more severe inflammatory clusters (P < 0.001), and β-diversity analysis demonstrated distinct microbiome profiles associated with each inflammatory cluster (P = 0.001). Proteobacteria and Pseudomonas at phylum and genus levels, respectively, were more enriched in clusters 2 and 3 than in clusters 1 and 4. Furthermore, patients in cluster 2 (rate ratio [RR], 1.49; 95% confidence interval [CI], 1.16-1.92) and cluster 3 (RR, 1.61; 95% CI, 1.12-2.32) were at higher risk of exacerbation over a 12-month follow-up compared with cluster 1, even after adjustment for prior exacerbation history. Conclusions: Bronchiectasis inflammatory endotypes are associated with distinct microbiome profiles and future exacerbation risk.

Cliques within the crowd: identifying medical conference attendee subgroups by their motivations for participation

Conferences enable rapid information sharing and networking that are vital to career development within academic communities. Addressing diverse attendee needs is challenging and getting it wrong wastes resources and dampens enthusiasm for the field. This study explores whether, and how, motivations for attendance can be grouped in relation to preferences to offer guidance to organizers and attendees. A pragmatic constructivist case study approach using mixed methods was adopted. Semi-structured interviews completed with key informants underwent thematic analysis. Survey results outlining attendees' perspectives underwent cluster and factor analysis. Stakeholder interviews (n = 13) suggested attendees could be grouped by motivations predictable from level of specialisation in a field and past engagement with conferences. From n = 1229 returned questionnaires, motivations were clustered into three factors: learning, personal and social. Three groups of attendees were identified. Group 1 (n = 500; 40.7%) was motivated by all factors. Group 2 (n = 345; 28.1%) was mainly motivated by the learning factor. Group 3 (n = 188; 15.3%) scored the social factor highest for in-person conferences and the learning factor highest for virtual meetings. All three groups expressed a preference for hybrid conferences in the future. This study indicates that medical conference attendees can be clustered based on their learning, personal and social motivations for attendance. The taxonomy enables organizers to tailor conference formats with guidance on how to utilize hybrid conferences, thereby enabling better catering to attendees' desires for knowledge gain relative to networking.

The Hypothalamus-pituitary-adrenocortical Response to Critical Illness: A Concept in Need of Revision

Based on insights obtained during the past decade, the classical concept of an activated hypothalamus-pituitary-adrenocortical axis in response to critical illness is in need of revision. After a brief central hypothalamus-pituitary-adrenocortical axis activation, the vital maintenance of increased systemic cortisol availability and action in response to critical illness is predominantly driven by peripheral adaptations rather than by an ongoing centrally activated several-fold increased production and secretion of cortisol. Besides the known reduction of cortisol-binding proteins that increases free cortisol, these peripheral responses comprise suppressed cortisol metabolism in liver and kidney, prolonging cortisol half-life, and local alterations in expression of 11βHSD1, glucocorticoid receptor-α (GRα), and FK506 binding protein 5 (FKBP51) that appear to titrate increased GRα action in vital organs and tissues while reducing GRα action in neutrophils, possibly preventing immune-suppressive off-target effects of increased systemic cortisol availability. Peripherally increased cortisol exerts negative feed-back inhibition at the pituitary level impairing processing of pro-opiomelanocortin into ACTH, thereby reducing ACTH-driven cortisol secretion, whereas ongoing central activation results in increased circulating pro-opiomelanocortin. These alterations seem adaptive and beneficial for the host in the short term. However, as a consequence, patients with prolonged critical illness who require intensive care for weeks or longer may develop a form of central adrenal insufficiency. The new findings supersede earlier concepts such as "relative," as opposed to "absolute," adrenal insufficiency and generalized systemic glucocorticoid resistance in the critically ill. The findings also question the scientific basis for broad implementation of stress dose hydrocortisone treatment of patients suffering from acute septic shock solely based on assumption of cortisol insufficiency.

COVID-19 vaccination acceptance, safety and side-effects in European patients with severe asthma

Background

Vaccination is vital for achieving population immunity to severe acute respiratory syndrome coronavirus 2, but vaccination hesitancy presents a threat to achieving widespread immunity. Vaccine acceptance in chronic potentially immunosuppressed patients is largely unclear, especially in patients with asthma. The aim of this study was to investigate the vaccination experience in people with severe asthma.

Methods

Questionnaires about vaccination beliefs (including the Vaccination Attitudes Examination (VAX) scale, a measure of vaccination hesitancy-related beliefs), vaccination side-effects, asthma control and overall safety perceptions following coronavirus disease 2019 (COVID-19) vaccination were sent to patients with severe asthma in 12 European countries between May and June 2021.

Results

660 participants returned completed questionnaires (87.4% response rate). Of these, 88% stated that they had been, or intended to be, vaccinated, 9.5% were undecided/hesitant and 3% had refused vaccination. Patients who hesitated or refused vaccination had more negative beliefs towards vaccination. Most patients reported mild (48.2%) or no side-effects (43.8%). Patients reporting severe side-effects (5.7%) had more negative beliefs. Most patients (88.8%) reported no change in asthma symptoms after vaccination, while 2.4% reported an improvement, 5.3% a slight deterioration and 1.2% a considerable deterioration. Almost all vaccinated (98%) patients would recommend vaccination to other severe asthma patients.

Conclusions

Uptake of vaccination in patients with severe asthma in Europe was high, with a small minority refusing vaccination. Beliefs predicted vaccination behaviour and side-effects. Vaccination had little impact on asthma control. Our findings in people with severe asthma support the broad message that COVID-19 vaccination is safe and well tolerated.

Consensus goals and standards for specialist cough clinics: the NEUROCOUGH international Delphi study

Background

Current guidelines on the management of chronic cough do not provide recommendations for the operation of specialist cough clinics. The objective of the present study was to develop expert consensus on goals and standard procedures for specialist cough clinics.

Methods

We undertook a modified Delphi process, whereby initial statements proposed by experts were categorised and presented back to panellists over two ranking rounds using an 11-point Likert scale to identify consensus.

Results

An international panel of 57 experts from 19 countries participated, with consensus reached on 15 out of 16 statements, covering the aims, roles and standard procedures of specialist cough clinics. Panellists agreed that specialist cough clinics offer optimal care for patients with chronic cough. They also agreed that history taking should enquire as to cough triggers, cough severity rating scales should be routinely used, and a minimum of chest radiography, spirometry and measurements of type 2 inflammatory markers should be undertaken in newly referred patients. The importance of specialist cough clinics in promoting clinical research and cough specialty training was acknowledged. Variability in healthcare resources and clinical needs between geographical regions was noted.

Conclusions

The Delphi exercise provides a platform and guidance for both established cough clinics and those in planning stages.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

European Network for ICU-Related Respiratory Infections (ENIRRIs): a multinational, prospective, cohort study of nosocomial LRTI

PURPOSE

Lower respiratory tract infections (LRTI) are the most frequent infectious complication in patients admitted to the intensive care unit (ICU). We aim to report the clinical characteristics of ICU-admitted patients due to nosocomial LRTI and to describe their microbiology and clinical outcomes.

METHODS

A prospective observational study was conducted in 13 countries over two continents from 9th May 2016 until 16th August 2019. Characteristics and outcomes of ventilator-associated pneumonia (VAP), ventilator-associated tracheobronchitis (VAT), ICU hospital-acquired pneumonia (ICU-HAP), HAP that required invasive ventilation (VHAP), and HAP in patients transferred to the ICU without invasive mechanical ventilation were collected. The clinical diagnosis and treatments were per clinical practice and not per protocol. Descriptive statistics were used to compare the study groups.

RESULTS

1060 patients with LRTI (72.5% male sex, median age 64 [50-74] years) were included in the study; 160 (15.1%) developed VAT, 556 (52.5%) VAP, 98 (9.2%) ICU-HAP, 152 (14.3%) HAP, and 94 (8.9%) VHAP. Patients with VHAP had higher serum procalcitonin (PCT) and Sequential Organ Failure Assessment (SOFA) scores. Patients with VAP or VHAP developed acute kidney injury, acute respiratory distress syndrome, multiple organ failure, or septic shock more often. One thousand eight patients had microbiological samples, and 711 (70.5%) had etiological microbiology identified. The most common microorganisms were Pseudomonas aeruginosa (18.4%) and Klebsiella spp (14.4%). In 382 patients (36%), the causative pathogen shows some antimicrobial resistance pattern. ICU, hospital and 28-day mortality were 30.8%, 37.5% and 27.5%, respectively. Patients with VHAP had the highest ICU, in-hospital and 28-day mortality rates.

CONCLUSION

VHAP patients presented the highest mortality among those admitted to the ICU. Multidrug-resistant pathogens frequently cause nosocomial LRTI in this multinational cohort study.

Clinical characteristics of chylothorax: results from the International Collaborative Effusion database

Background

Chylothorax is an uncommon medical condition for which limited data are available regarding the contemporary aetiology, management and outcomes. The goal of this study was to better define these poorly characterised features.

Methods

The medical records of adult patients diagnosed with chylothorax at 12 centres across Europe, America and South Africa from 2009-2021 were retrospectively reviewed. Descriptive and inferential statistics were performed.

Results

77 patients (median age 69 years, male to female ratio 1.5) were included. Subacute dyspnoea was the most typical presenting symptom (66%). The commonest cause of chylothorax was malignancy (68.8%), with lymphoma accounting for 62% of these cases. Other aetiologies were trauma (13%), inflammatory/miscellaneous conditions (11.7%) and idiopathic cases (6.5%). At the initial thoracentesis, the pleural fluid appeared milky in 73%, was exudative in 89% and exhibited triglyceride concentrations >100 mg·dL-1 in 88%. Lymphangiography/lymphoscintigraphy were rarely ordered (3%), and demonstration of chylomicrons in pleural fluid was never ascertained. 67% of patients required interventional pleural procedures. Dietary measures were infrequently followed (36%). No patient underwent thoracic duct ligation or embolisation. Morbidity included infections (18%), and thrombosis in malignant aetiologies (16%). The 1-year mortality was 47%. Pleural fluid protein >3.5 mg·dL-1 (sub-distribution hazard ratio (SHR) 4.346) or lactate dehydrogenase <500 U·L-1 (SHR 10.21) increased the likelihood of effusion resolution. Pleural fluid protein ≤3.5 mg·dL-1 (HR 4.047), bilateral effusions (HR 2.749) and a history of respiratory disease (HR 2.428) negatively influenced survival.

Conclusion

Chylothoraces have a poor prognosis and most require pleural interventions. Despite the standard recommendations, lymphatic imaging is seldom used, nor are dietary restrictions followed.

Autoantibodies Neutralizing Type I IFNs in the Bronchoalveolar Lavage of at Least 10% of Patients During Life-Threatening COVID-19 Pneumonia

Autoantibodies (auto-Abs) neutralizing type I interferons (IFNs) are found in the blood of at least 15% of unvaccinated patients with life-threatening COVID-19 pneumonia. We report here the presence of auto-Abs neutralizing type I IFNs in the bronchoalveolar lavage (BAL) of 54 of the 415 unvaccinated patients (13%) with life-threatening COVID-19 pneumonia tested. The 54 individuals with neutralizing auto-Abs in the BAL included 45 (11%) with auto-Abs against IFN-α2, 37 (9%) with auto-Abs against IFN-ω, 54 (13%) with auto-Abs against IFN-α2 and/or ω, and five (1%) with auto-Abs against IFN-β, including three (0.7%) with auto-Abs neutralizing IFN-α2, IFN-ω, and IFN-β, and two (0.5%) with auto-Abs neutralizing IFN-α2 and IFN-β. Auto-Abs against IFN-α2 also neutralize the other 12 subtypes of IFN-α. Paired plasma samples were available for 95 patients. All seven patients with paired samples who had detectable auto-Abs in BAL also had detectable auto-Abs in plasma, and one patient had auto-Abs detectable only in blood. Auto-Abs neutralizing type I IFNs are, therefore, present in the alveolar space of at least 10% of patients with life-threatening COVID-19 pneumonia. These findings suggest that these auto-Abs impair type I IFN immunity in the lower respiratory tract, thereby contributing to hypoxemic COVID-19 pneumonia.

Antiviral CD8+ T-cell immune responses are impaired by cigarette smoke and in COPD

BACKGROUND

Virus infections drive COPD exacerbations and progression. Antiviral immunity centres on the activation of virus-specific CD8+ T-cells by viral epitopes presented on major histocompatibility complex (MHC) class I molecules of infected cells. These epitopes are generated by the immunoproteasome, a specialised intracellular protein degradation machine, which is induced by antiviral cytokines in infected cells.

METHODS

We analysed the effects of cigarette smoke on cytokine- and virus-mediated induction of the immunoproteasome in vitro, ex vivo and in vivo using RNA and Western blot analyses. CD8+ T-cell activation was determined in co-culture assays with cigarette smoke-exposed influenza A virus (IAV)-infected cells. Mass-spectrometry-based analysis of MHC class I-bound peptides uncovered the effects of cigarette smoke on inflammatory antigen presentation in lung cells. IAV-specific CD8+ T-cell numbers were determined in patients' peripheral blood using tetramer technology.

RESULTS

Cigarette smoke impaired the induction of the immunoproteasome by cytokine signalling and viral infection in lung cells in vitro, ex vivo and in vivo. In addition, cigarette smoke altered the peptide repertoire of antigens presented on MHC class I molecules under inflammatory conditions. Importantly, MHC class I-mediated activation of IAV-specific CD8+ T-cells was dampened by cigarette smoke. COPD patients exhibited reduced numbers of circulating IAV-specific CD8+ T-cells compared to healthy controls and asthmatics.

CONCLUSION

Our data indicate that cigarette smoke interferes with MHC class I antigen generation and presentation and thereby contributes to impaired activation of CD8+ T-cells upon virus infection. This adds important mechanistic insight on how cigarette smoke mediates increased susceptibility of smokers and COPD patients to viral infections.

Phenotyping asthma with airflow obstruction in middle-aged and older adults: a CADSET clinical research collaboration

BACKGROUND

The prevalence and clinical profile of asthma with airflow obstruction (AO) remain uncertain. We aimed to phenotype AO in population- and clinic-based cohorts.

METHODS

This cross-sectional multicohort study included adults ≥50 years from nine CADSET cohorts with spirometry data (N=69 789). AO was defined as ever diagnosed asthma with pre-BD or post-BD FEV1/FVC <0.7 in population-based and clinic-based cohorts, respectively. Clinical characteristics and comorbidities of AO were compared with asthma without airflow obstruction (asthma-only) and chronic obstructive pulmonary disease (COPD) without asthma history (COPD-only). ORs for comorbidities adjusted for age, sex, smoking status and body mass index (BMI) were meta-analysed using a random effects model.

RESULTS

The prevalence of AO was 2.1% (95% CI 2.0% to 2.2%) in population-based, 21.1% (95% CI 18.6% to 23.8%) in asthma-based and 16.9% (95% CI 15.8% to 17.9%) in COPD-based cohorts. AO patients had more often clinically relevant dyspnoea (modified Medical Research Council score ≥2) than asthma-only (+14.4 and +14.7 percentage points) and COPD-only (+24.0 and +5.0 percentage points) in population-based and clinic-based cohorts, respectively. AO patients had more often elevated blood eosinophil counts (>300 cells/µL), although only significant in population-based cohorts. Compared with asthma-only, AO patients were more often men, current smokers, with a lower BMI, had less often obesity and had more often chronic bronchitis. Compared with COPD-only, AO patients were younger, less often current smokers and had less pack-years. In the general population, AO patients had a higher risk of coronary artery disease than asthma-only and COPD-only (OR=2.09 (95% CI 1.26 to 3.47) and OR=1.89 (95% CI 1.10 to 3.24), respectively) and of depression (OR=1.41 (95% CI 1.19 to 1.67)), osteoporosis (OR=2.30 (95% CI 1.43 to 3.72)) and gastro-oesophageal reflux disease (OR=1.68 (95% CI 1.06 to 2.68)) than COPD-only, independent of age, sex, smoking status and BMI.

CONCLUSIONS

AO is a relatively prevalent respiratory phenotype associated with more dyspnoea and a higher risk of coronary artery disease and elevated blood eosinophil counts in the general population compared with both asthma-only and COPD-only.

Identification of paired-related Homeobox Protein 1 as a key mesenchymal transcription factor in pulmonary fibrosis

Matrix remodeling is a salient feature of idiopathic pulmonary fibrosis (IPF). Targeting cells driving matrix remodeling could be a promising avenue for IPF treatment. Analysis of transcriptomic database identified the mesenchymal transcription factor PRRX1 as upregulated in IPF. PRRX1, strongly expressed by lung fibroblasts, was regulated by a TGF-b/PGE2 balance in vitro in control and IPF human lung fibroblasts, while IPF fibroblast-derived matrix increased PRRX1 expression in a PDGFR dependent manner in control ones. PRRX1 inhibition decreased human lung fibroblast proliferation by downregulating the expression of S phase cyclins. PRRX1 inhibition also impacted TGF-β driven myofibroblastic differentiation by inhibiting SMAD2/3 phosphorylation through phosphatase PPM1A upregulation and TGFBR2 downregulation, leading to TGF-β response global decrease. Finally, targeted inhibition of Prrx1 attenuated fibrotic remodeling in vivo with intra-tracheal antisense oligonucleotides in bleomycin mouse model of lung fibrosis and ex vivo using human and mouse precision-cut lung slices. Our results identified PRRX1 as a key mesenchymal transcription factor during lung fibrogenesis.

Quality control in respiratory oscillometry: reproducibility measures ignoring reactance?

This study demonstrates the inadequacy of the current technical standards of oscillometry that are based on the within-trial reproducibility of the lowest-frequency R_rs, and suggests the use of a simple variability measure encompassing both R_rs and X_rs https://bit.ly/3AYRid6.

What bothers severe asthma patients most? A paired patient-clinician study across seven European countries

Introduction

Severe asthma is a complex, multidimensional disease. Optimal treatment, adherence and outcomes require shared decision-making, rooted in mutual understanding between patient and clinician. This study used a novel, patient-centred approach to examine the most bothersome aspects of severe asthma to patients, as seen from both perspectives in asthma registries.

Methods

Across seven countries, 126 patients with severe asthma completed an open-ended survey regarding most the bothersome aspect(s) of their asthma. Patients' responses were linked with their treating clinician who also completed a free-text survey about each patient's most bothersome aspect(s). Responses were coded using content analysis, and patient and clinician responses were compared. Finally, asthma registries that are part of the SHARP (Severe Heterogeneous Asthma Research collaboration, Patient-centred) Clinical Research Collaboration were examined to see the extent to which they reflected the most bothersome aspects reported by patients.

Results

88 codes and 10 themes were identified. Clinicians were more focused on direct physical symptoms and were less focused on "holistic" aspects such as the effort required to self-manage the disease. Clinicians accurately identified a most bothersome symptom for 29% of patients. Agreement was particularly low with younger patients and those using oral corticosteroids infrequently. In asthma registries, patient aspects were predominantly represented in questionnaires.

Conclusions

Results demonstrated different perspectives and priorities between patients and clinicians, with clinicians more focused on physical aspects. These differences must be considered when treating individual patients, and within multidisciplinary treatment teams. The use of questionnaires that include multifaceted aspects of disease may result in improved asthma research.

Daily allergy burden and heart rate characteristics in adults with allergic rhinitis based on a wearable telemonitoring system

BACKGROUND

Allergic rhinitis includes a certain degree of autonomic imbalance. However, no information is available on how daily changes in allergy burden affect autonomic imbalance. We aimed to estimate associations between daily allergy burden (allergy symptoms and mood) and daily heart rate characteristics (resting heart rate and sample entropy, both biomarkers of autonomic balance) of adults with allergic rhinitis, based on real-world measurements with a wearable telemonitoring system.

METHODS

Adults with a tree pollen allergy used a smartphone application to self-report daily allergy symptoms (score 0-44) and mood (score 0-4), and a Mio Alpha 2 wristwatch to collect heart rate characteristics during two pollen seasons of hazel, alder and birch in Belgium. Associations between daily allergy burden and heart rate characteristics were estimated using linear mixed effects distributed lag models with a random intercept for individuals and adjusted for potential confounders.

RESULTS

Analyses included 2497 participant-days of 72 participants. A one-point increase in allergy symptom score was associated with an increase in next-day resting heart rate of 0.08 (95% CI: 0.02-0.15) beats per minute. A one-point increase in mood score was associated with an increase in same-day sample entropy of 0.80 (95% CI: 0.34-1.26) × 10^-2 . No associations were found between allergy symptoms and heart rate sample entropy, nor between mood and resting heart rate.

CONCLUSION

Daily repeated measurements with a wearable telemonitoring system revealed that the daily allergy burden of adults with allergic rhinitis has systemic effects beyond merely the respiratory system.

Clinical outcomes of bronchiectasis in India: data from the EMBARC/Respiratory Research Network of India registry

BACKGROUND

Identifying risk factors for poor outcomes can help with risk stratification and targeting of treatment. Risk factors for mortality and exacerbations have been identified in bronchiectasis but have been almost exclusively studied in European and North American populations. This study investigated the risk factors for poor outcome in a large population of bronchiectasis patients enrolled in India.

METHODS

The European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) and Respiratory Research Network of India (EMBARC-India) registry is a prospective observational study of adults with computed tomography-confirmed bronchiectasis enrolled at 31 sites across India. Baseline characteristics of patients were used to investigate associations with key clinical outcomes: mortality, severe exacerbations requiring hospital admission, overall exacerbation frequency and decline in forced expiratory volume in 1 s.

RESULTS

1018 patients with at least 12-month follow-up data were enrolled in the follow-up study. Frequent exacerbations (≥3 per year) at baseline were associated with an increased risk of mortality (hazard ratio (HR) 3.23, 95% CI 1.39-7.50), severe exacerbations (HR 2.71, 95% CI 1.92-3.83), future exacerbations (incidence rate ratio (IRR) 3.08, 95% CI 2.36-4.01) and lung function decline. Coexisting COPD, dyspnoea and current cigarette smoking were similarly associated with a worse outcome across all end-points studied. Additional predictors of mortality and severe exacerbations were increasing age and cardiovascular comorbidity. Infection with Gram-negative pathogens (predominantly Klebsiella pneumoniae) was independently associated with increased mortality (HR 3.13, 95% CI 1.62-6.06), while Pseudomonas aeruginosa infection was associated with severe exacerbations (HR 1.41, 95% CI 1.01-1.97) and overall exacerbation rate (IRR 1.47, 95% CI 1.13-1.91).

CONCLUSIONS

This study identifies risk factors for morbidity and mortality among bronchiectasis patients in India. Identification of these risk factors may support treatment approaches optimised to an Asian setting.

Heart rate and oxygen uptake kinetics obtained from continuous measurements with wearable devices during outdoor walks of patients with COPD

Objective

Continuous physiological measurements during a laboratory-based exercise test can provide physiological biomarkers, such as heart rate (HR) and oxygen uptake (V̇O₂) kinetics, that carry clinically relevant information. In contrast, it is not clear how continuous data generated by wearable devices during daily-life routines could provide meaningful biomarkers. We aimed to determine whether valid HR and V̇O₂ kinetics can be obtained from measurements with wearable devices during outdoor walks in patients with chronic obstructive pulmonary disease (COPD).

Methods

HR (Polar Belt) and V̇O₂(METAMAX3B) were measured during 93 physical activity transitions performed by eight patients with COPD during three different outdoor walks (n_tr= 77) and a 6-minute walk test (n_tr= 16). HR and V̇O₂ kinetics were calculated every time a participant started a walk, finished a walk or walked upstairs. HR and V̇O₂ kinetics were considered valid if the response magnitude and model fit were adequate, and model parameters were reliable.

Results

Continuous measurements with wearable devices provided valid HR kinetics when COPD patients started or finished (range 63%-100%) the different outdoor walks and valid V̇O₂ kinetics when they finished (range 63%-100%) an outdoor walk. The amount of valid kinetics and kinetic model performance was comparable between outdoor walks and a laboratory-based exercise test (p > .05).

Conclusion

We envision that the presented approach could improve telemonitoring applications of patients with COPD by providing regular, unsupervised assessments of HR kinetics during daily-life routines. This could allow to early identify a decline in the patients' dynamic physiological functioning, physical fitness and/or health status.

Extracellular Hsp70 modulates 16HBE cells' inflammatory responses to cigarette smoke and bacterial components lipopolysaccharide and lipoteichoic acid

Cigarette smoke is a major risk factor for chronic obstructive pulmonary disease (COPD), leading to chronic inflammation, while bacterial components lipopolysaccharide (LPS) and lipoteichoic acid (LTA) are often present in airways of COPD patients, especially during exacerbations.We hypothesised that extracellular heat shock protein 70 (eHsp70), a damage-associated molecular pattern elevated in serum of COPD patients, induces inflammation and alters cigarette smoke and LPS/LTA-induced inflammatory effects in the airway epithelium.We used 16HBE cells exposed to recombinant human (rh)Hsp70 and its combinations with cigarette smoke extract (CSE), LPS or LTA to investigate those assumptions, and we determined pro-inflammatory cytokines' secretion as well as TLR2 and TLR4 gene expression.rhHsp70 and CSE alone stimulated IL-6, IL-8 and TNF-α secretion. CSE and rhHsp70 had antagonistic effect on IL-6 secretion, while combinations of LPS or LTA with rhHsp70 showed antagonistic effect on TNF-α release. By using specific inhibitors, we demonstrated that effects of rhHsp70 on cytokines' secretion were mediated via NF-κB and/or MAPK signalling pathways. rhHsp70 increased, and CSE decreased TLR2 gene expression compared to untreated cells, but their combinations increased it compared to CSE alone. LPS and rhHsp70 combinations decreased TLR2 gene expression compared to untreated cells. TLR4 expression was not induced by any of the treatments.In conclusion, we demonstrated that extracellular Hsp70 modulates pro-inflammatory responses of human airway epithelial cells to cigarette smoke and bacterial components LPS and LTA. Simultaneous presence of those compounds and their interactions might lead to inappropriate immune responses and adverse consequences in COPD.

COVID-19 follow-up programs across Europe: an ERS END-COVID CRC survey

SARS-CoV-2 is responsible for a multi-organ syndrome that can last over 12 months after the initial infection, which includes pulmonary and systemic consequences with residual radiological or functional alterations [1–3]. According to international guidelines, post-COVID-19 syndrome or condition is defined by a variety of signs and symptoms occurring during or after an infection consistent with COVID-19, lasting for more than 8–12 weeks and not explained by an alternative diagnosis [4, 5]. Main symptoms are fatigue, dyspnoea, arthralgia, chest pain, cough and neurocognitive impairment [6].

A large heterogeneity in the management of post-COVID-19 syndrome and in standard operating procedures for COVID-19 follow-up programmes across Europe exists https://bit.ly/3OdPxgF

Critical Illness-induced Corticosteroid Insufficiency: What It Is Not and What It Could Be

Critical illnesses are hallmarked by increased systemic cortisol availability, a vital part of the stress response. Acute stress may trigger a life-threatening adrenal crisis when a disease of the hypothalamic-pituitary-adrenal (HPA) axis is present and not adequately treated with stress doses of hydrocortisone. Stress doses of hydrocortisone are also used to reduce high vasopressor need in patients suffering from septic shock, in the absence of adrenal insufficiency. Research performed over the last 10 years focusing on the HPA axis during critical illness has led to the insight that neither of these conditions can be labeled "critical illness-induced corticosteroid insufficiency" or CIRCI. Instead, these data suggested using the term CIRCI for a condition that may develop in prolonged critically ill patients. Indeed, when patients remain dependent on vital organ support for weeks, they are at risk of acquiring central adrenal insufficiency. The sustained increase in systemic glucocorticoid availability, mainly brought about by suppressed circulating cortisol-binding proteins and suppressed hepatic/renal cortisol metabolism, exerts negative feedback inhibition at the hypothalamus/pituitary, while high levels of other glucocorticoid receptor ligands, such as bile acids, and drugs, such as opioids, may further suppress adrenocorticotropic hormone (ACTH) secretion. The adrenal cortex, depleted from ACTH-mediated trophic signaling for weeks, may become structurally and functionally impaired, resulting in insufficient cortisol production. Such a central HPA axis suppression may be maladaptive by contributing to lingering vasopressor need and encephalopathy, hence preventing recovery. Here, we review this concept of CIRCI and we advise on how to recognize and treat this poorly understood condition.

Mining the Plasma Proteome for Insights into the Molecular Pathology of Pulmonary Arterial Hypertension

Rationale: Pulmonary arterial hypertension (PAH) is characterized by structural remodeling of pulmonary arteries and arterioles. Underlying biological processes are likely reflected in a perturbation of circulating proteins. Objectives: To quantify and analyze the plasma proteome of patients with PAH using inherited genetic variation to inform on underlying molecular drivers. Methods: An aptamer-based assay was used to measure plasma proteins in 357 patients with idiopathic or heritable PAH, 103 healthy volunteers, and 23 relatives of patients with PAH. In discovery and replication subgroups, the plasma proteomes of PAH and healthy individuals were compared, and the relationship to transplantation-free survival in PAH was determined. To examine causal relationships to PAH, protein quantitative trait loci (pQTL) that influenced protein levels in the patient population were used as instruments for Mendelian randomization (MR) analysis. Measurements and Main Results: From 4,152 annotated plasma proteins, levels of 208 differed between patients with PAH and healthy subjects, and 49 predicted long-term survival. MR based on cis-pQTL located in proximity to the encoding gene for proteins that were prognostic and distinguished PAH from health estimated an adverse effect for higher levels of netrin-4 (odds ratio [OR], 1.55; 95% confidence interval [CI], 1.16-2.08) and a protective effect for higher levels of thrombospondin-2 (OR, 0.83; 95% CI, 0.74-0.94) on PAH. Both proteins tracked the development of PAH in previously healthy relatives and changes in thrombospondin-2 associated with pulmonary arterial pressure at disease onset. Conclusions: Integrated analysis of the plasma proteome and genome implicates two secreted matrix-binding proteins, netrin-4 and thrombospondin-2, in the pathobiology of PAH.

Impact of Hydrocortisone and of CRH Infusion on the Hypothalamus-Pituitary-Adrenocortical Axis of Septic Male Mice

PURPOSE

Sepsis is hallmarked by high plasma cortisol/corticosterone (CORT), low adrenocorticotropic hormone (ACTH), and high pro-opiomelanocortin (POMC). While corticotropin-releasing hormone-(CRH) and arginine-vasopressin (AVP)-driven pituitary POMC expression remains active, POMC processing into ACTH becomes impaired. Low ACTH is accompanied by loss of adrenocortical structure, although steroidogenic enzymes remain expressed. We hypothesized that treatment of sepsis with hydrocortisone (HC) aggravates this phenotype whereas CRH infusion safeguards ACTH-driven adrenocortical structure.

METHODS

In a fluid-resuscitated, antibiotics-treated mouse model of prolonged sepsis, we compared the effects of HC and CRH infusion with placebo on plasma ACTH, POMC, and CORT; on markers of hypothalamic CRH and AVP signaling and pituitary POMC processing; and on the adrenocortical structure and markers of steroidogenesis. In adrenal explants, we studied the steroidogenic capacity of POMC.

RESULTS

During sepsis, HC further suppressed plasma ACTH, but not POMC, predominantly by suppressing sepsis-activated CRH/AVP-signaling pathways. In contrast, in CRH-treated sepsis, plasma ACTH was normalized following restoration of pituitary POMC processing. The sepsis-induced rise in markers of adrenocortical steroidogenesis was unaltered by CRH and suppressed partially by HC, which also increased adrenal markers of inflammation. Ex vivo stimulation of adrenal explants with POMC increased CORT as effectively as an equimolar dose of ACTH.

CONCLUSIONS

Treatment of sepsis with HC impaired integrity and function of the hypothalamic-pituitary-adrenal axis at the level of the pituitary and the adrenal cortex while CRH restored pituitary POMC processing without affecting the adrenal cortex. Sepsis-induced high-circulating POMC may be responsible for ongoing adrenocortical steroidogenesis despite low ACTH.

Granulomatous-lymphocytic interstitial lung disease: an international research prioritisation

The first ever research prioritisation exercise in GLILD: this survey identified areas of interest in the diagnosis, treatment and management of GLILD, which can be used as a roadmap for future research https://bit.ly/3nVuzti.

Combined Metabolic and Chemical (CoMetChem) Labeling Using Stable Isotopes-a Strategy to Reveal Site-Specific Histone Acetylation and Deacetylation Rates by LC-MS

Histone acetylation is an important, reversible post-translational protein modification and a hallmark of epigenetic regulation. However, little is known about the dynamics of this process, due to the lack of analytical methods that can capture site-specific acetylation and deacetylation reactions. We present a new approach that combines metabolic and chemical labeling (CoMetChem) using uniformly 13C-labeled glucose and stable isotope-labeled acetic anhydride. Thereby, chemically equivalent, fully acetylated histone species are generated, enabling accurate relative quantification of site-specific lysine acetylation dynamics in tryptic peptides using high-resolution mass spectrometry. We show that CoMetChem enables site-specific quantification of the incorporation or loss of lysine acetylation over time, allowing the determination of reaction rates for acetylation and deacetylation. Thus, the CoMetChem methodology provides a comprehensive description of site-specific acetylation dynamics.

The good and the bad about separation anxiety: roles of IL-22 and IL-22BP in liver pathologies

The human liver fulfills several vital tasks daily and possesses an impressive ability to self-regenerate. However, the capacity of this self-healing process can be exhausted by a variety of different liver diseases, such as alcoholic liver damage, viral hepatitis, or hepatocellular carcinoma. Over time, all these diseases generally lead to progressive liver failure that can become fatal if left untreated. Thus, a great effort has been directed towards the development of innovative therapies. The most recently discovered therapies often involve modifying the patient's immune system to enhance a beneficial immune response. Current data suggest that, among others, the cytokine IL-22 might be a promising therapeutical candidate. IL-22 and its endogenous antagonist, IL-22BP, have been under thorough scientific investigation for nearly 20 years. While IL-22 is mainly produced by TH22 cells, ILC3s, NKT cells, or γδ T cells, sources of IL-22BP include dendritic cells, eosinophils, and CD4+ cells. In many settings, IL-22 was shown to promote regenerative potential and, thus, could protect tissues from pathogens and damage. However, the effects of IL-22 during carcinogenesis are more ambiguous and depend on the tumor entity and microenvironment. In line with its capabilities of neutralizing IL-22 in vivo, IL-22BP possesses often, but not always, an inverse expression pattern compared to its ligand. In this comprehensive review, we will summarize past and current findings regarding the roles of IL-22 and IL-22BP in liver diseases with a particular focus on the leading causes of advanced liver failure, namely, liver infections, liver damage, and liver malignancies.

Management of hospitalised adults with coronavirus disease 2019 (COVID-19): a European Respiratory Society living guideline

INTRODUCTION

Hospitalised patients with coronavirus disease 2019 (COVID-19) as a result of SARS-CoV-2 infection have a high mortality rate and frequently require noninvasive respiratory support or invasive ventilation. Optimising and standardising management through evidence-based guidelines may improve quality of care and therefore patient outcomes.

METHODS

A task force from the European Respiratory Society and endorsed by the Chinese Thoracic Society identified priority interventions (pharmacological and non-pharmacological) for the initial version of this "living guideline" using the PICO (population, intervention, comparator, outcome) format. The GRADE approach was used for assessing the quality of evidence and strength of recommendations. Systematic literature reviews were performed, and data pooled by meta-analysis where possible. Evidence tables were presented and evidence to decision frameworks were used to formulate recommendations.

RESULTS

Based on the available evidence at the time of guideline development (20 February, 2021), the panel makes a strong recommendation in favour of the use of systemic corticosteroids in patients requiring supplementary oxygen or ventilatory support, and for the use of anticoagulation in hospitalised patients. The panel makes a conditional recommendation for interleukin (IL)-6 receptor antagonist monoclonal antibody treatment and high-flow nasal oxygen or continuous positive airway pressure in patients with hypoxaemic respiratory failure. The panel make strong recommendations against the use of hydroxychloroquine and lopinavir-ritonavir. Conditional recommendations are made against the use of azithromycin, hydroxychloroquine combined with azithromycin, colchicine, and remdesivir, in the latter case specifically in patients requiring invasive mechanical ventilation. No recommendation was made for remdesivir in patients requiring supplemental oxygen. Further recommendations for research are made.

CONCLUSION

The evidence base for management of COVID-19 now supports strong recommendations in favour and against specific interventions. These guidelines will be regularly updated as further evidence becomes available.

Bronchoscopic diagnosis and treatment of endobronchial carcinoid: case report and review of the literature

Carcinoid tumours are rare neuroendocrine neoplasms that mostly occur in younger adults with low tendencies to metastasise. Based on their histological characteristics, they are divided into typical and atypical subtypes. The most common presenting symptoms are due to central airway obstruction. The first step in the diagnostic assessment should be a computed tomography (CT) scan, as it provides information both for local tumour extent and lymph node involvement. Bronchoscopy is the main tool for histological confirmation, evaluation of bronchial wall invasion and removal of endobronchial manifestation with subsequent resolution of atelectasis. Endobronchial ultrasound may be necessary to rule out lymph node metastasis. Somatostatin receptor scintigraphy in combination with CT can rule out further metastatic disease.Surgical resection using parenchyma-sparing techniques remains the gold standard for treatment. For selected patients, endobronchial therapy could be an alternative for minimal invasiveness. Long-term follow-up is suggested due to the high likelihood of recurrence.Here, we describe our clinical experience in a 35-year-old male patient who originally presented with haemoptysis and a central polypoid tumour in the left main bronchus revealed by a CT scan. The histological characteristics were indicative of a typical carcinoid. The patient was treated using an endobronchial approach only. No complications and no recurrences have been observed in a follow-up of 2 years.

ERS International Congress 2020: highlights from the Epidemiology and Environment Assembly

In this article, early career members of the Epidemiology and Environment Assembly of the European Respiratory Society (ERS) summarise a selection of five sessions from the ERS 2020 Virtual International Congress. The topics covered include risk factors for chronic respiratory diseases over the life course, from early life origins to occupational exposures in adulthood, and the interplay between these risk factors, including gene-environment interactions. Novel results were also presented on smoking prevention and potential risks of vaping. Finally, the challenges and opportunities for epidemiological and environmental research brought by the coronavirus disease 2019 (COVID-19) pandemic were a major topic of this year's congress.

M. tuberculosis infection of human iPSC-derived macrophages reveals complex membrane dynamics during xenophagy evasion

Xenophagy is an important cellular defence mechanism against cytosol-invading pathogens, such as Mycobacterium tuberculosis (Mtb). Activation of xenophagy in macrophages targets Mtb to autophagosomes; however, how Mtb is targeted to autophagosomes in human macrophages at a high spatial and temporal resolution is unknown. Here, we use human induced pluripotent stem cell-derived macrophages (iPSDMs) to study the human macrophage response to Mtb infection and the role of the ESX-1 type VII secretion system. Using RNA-seq, we identify ESX-1-dependent transcriptional responses in iPSDMs after infection with Mtb. This analysis revealed differential inflammatory responses and dysregulated pathways such as eukaryotic initiation factor 2 (eIF2) signalling and protein ubiquitylation. Moreover, live-cell imaging revealed that Mtb infection in human macrophages induces dynamic ESX-1-dependent, LC3B-positive tubulovesicular autophagosomes (LC3-TVS). Through a correlative live-cell and focused ion beam scanning electron microscopy (FIB SEM) approach, we show that upon phagosomal rupture, Mtb induces the formation of LC3-TVS, from which the bacterium is able to escape to reside in the cytosol. Thus, iPSDMs represent a valuable model for studying spatiotemporal dynamics of human macrophage-Mtb interactions, and Mtb is able to evade capture by autophagic compartments.

Mediterranean diet during pregnancy and childhood respiratory and atopic outcomes: birth cohort study

Evidence for associations between Mediterranean diet during pregnancy and childhood asthma, allergy and related outcomes is conflicting. Few cohorts have followed children to school age, and none have considered lung function.In the Avon Longitudinal Study of Parents and Children, we analysed associations between maternal Mediterranean diet score during pregnancy (estimated by a food frequency questionnaire, using an a priori defined score adapted to pregnant women; score ranging from 0 (low adherence) to 7 (high adherence)) and current doctor-diagnosed asthma, wheeze, eczema, hay fever, atopy and lung function in 8907 children at 7-9 years. Interaction between maternal Mediterranean diet and maternal smoking in pregnancy was investigated.The maternal Mediterranean diet score was not associated with asthma or other allergic outcomes. Weak positive associations were found between maternal Mediterranean diet score and childhood maximal mid-expiratory flow (forced expiratory flow at 25-75% of forced vital capacity (FEF25-75%)) after controlling for confounders. Higher Mediterranean diet scores were associated with increased FEF25-75% z-scores adjusted for age, height and sex (β 0.06, 95% CI 0.01-0.12; p=0.03, comparing a score of 4-7 versus a score of 0-3). Stratifying associations by maternal smoking during pregnancy showed that associations with FEF25-75% were only seen in children of never-/passive-smoking mothers, but no evidence for a statistically significant interaction was found.Results suggest adherence to a Mediterranean diet during pregnancy may be associated with increased small airway function in childhood, but we found no evidence for a reduced risk of asthma or other allergic outcomes.

E-cigarettes: Effects in phagocytosis and cytokines response against Mycobacterium tuberculosis

Cigarette smoking and tuberculosis are a significant cause of death worldwide. Several epidemiological studies have demonstrated cigarette smoking is a risk factor for tuberculosis. Electronic cigarettes have recently appeared as a healthier alternative to conventional smoking, although their impact in tuberculosis is not well understood. The aim of this study was to explore the effect of electronic cigarettes in phagocytosis of Mycobacterium tuberculosis and cytokines production. In vitro infection was carried out by exposing THP-1 macrophages to four electronic vapor extracts and the intracellular burden of M. tuberculosis was determined. The percentage of infection was evaluated by confocal microscopy and the cytokine production by Luminex. A reduction of intracellular M. tuberculosis burden in THP-1 macrophages was found after its exposure to electronic vapor extract; the same trend was observed by confocal microscopy when Mycobacterium bovis BCG-GFP strain was used. Electronic cigarettes stimulate a pro-inflammatory cytokine response. We conclude that electronic cigarettes impair the phagocytic function and the cytokine response to M. tuberculosis.

Transcriptional regulatory model of fibrosis progression in the human lung

To develop a systems biology model of fibrosis progression within the human lung we performed RNA sequencing and microRNA analysis on 95 samples obtained from 10 idiopathic pulmonary fibrosis (IPF) and 6 control lungs. Extent of fibrosis in each sample was assessed by microCT-measured alveolar surface density (ASD) and confirmed by histology. Regulatory gene expression networks were identified using linear mixed-effect models and dynamic regulatory events miner (DREM). Differential gene expression analysis identified a core set of genes increased or decreased before fibrosis was histologically evident that continued to change with advanced fibrosis. DREM generated a systems biology model (www.sb.cs.cmu.edu/IPFReg) that identified progressively divergent gene expression tracks with microRNAs and transcription factors that specifically regulate mild or advanced fibrosis. We confirmed model predictions by demonstrating that expression of POU2AF1, previously unassociated with lung fibrosis but proposed by the model as regulator, is increased in B lymphocytes in IPF lungs and that POU2AF1-knockout mice were protected from bleomycin-induced lung fibrosis. Our results reveal distinct regulation of gene expression changes in IPF tissue that remained structurally normal compared with moderate or advanced fibrosis and suggest distinct regulatory mechanisms for each stage.

Exercise Training in Patients with Chronic Respiratory Diseases: Are Cardiovascular Comorbidities and Outcomes Taken into Account?-A Systematic Review

Patients with chronic obstructive pulmonary disease (COPD), asthma and interstitial lung diseases (ILD) frequently suffer from cardiovascular comorbidities (CVC). Exercise training is a cornerstone intervention for the management of these conditions, however recommendations on tailoring programmes to patients suffering from respiratory diseases and CVC are scarce. This systematic review aimed to identify the eligibility criteria used to select patients with COPD, asthma or ILD and CVC to exercise programmes; assess the impact of exercise on cardiovascular outcomes; and identify how exercise programmes were tailored to CVC. PubMed, Scopus, Web of Science and Cochrane were searched. Three reviewers extracted the data and two reviewers independently assessed the quality of studies with the Quality Assessment Tool for Quantitative Studies. MetaXL 5.3 was used to calculate the individual and pooled effect sizes (ES). Most studies (58.9%) excluded patients with both stable and unstable CVC. In total, 26/42 studies reported cardiovascular outcomes. Resting heart rate was the most reported outcome measure (n = 13) and a small statistically significant effect (ES = -0.23) of exercise training on resting heart rate of patients with COPD was found. No specific adjustments to exercise prescription were described. Few studies have included patients with CVC. There was a lack of tailoring of exercise programmes and limited effects were found. Future studies should explore the effect of tailored exercise programmes on relevant outcome measures in respiratory patients with CVC.

An airway epithelial IL-17A response signature identifies a steroid-unresponsive COPD patient subgroup

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a heterogeneous smoking-related disease characterized by airway obstruction and inflammation. This inflammation may persist even after smoking cessation and responds variably to corticosteroids. Personalizing treatment to biologically similar "molecular phenotypes" may improve therapeutic efficacy in COPD. IL-17A is involved in neutrophilic inflammation and corticosteroid resistance, and thus may be particularly important in a COPD molecular phenotype.

METHODS

We generated a gene expression signature of IL-17A response in bronchial airway epithelial brushings from smokers with and without COPD (n = 238), and validated it using data from 2 randomized trials of IL-17 blockade in psoriasis. This IL-17 signature was related to clinical and pathologic characteristics in 2 additional human studies of COPD: (a) SPIROMICS (n = 47), which included former and current smokers with COPD, and (b) GLUCOLD (n = 79), in which COPD participants were randomized to placebo or corticosteroids.

RESULTS

The IL-17 signature was associated with an inflammatory profile characteristic of an IL-17 response, including increased airway neutrophils and macrophages. In SPIROMICS the signature was associated with increased airway obstruction and functional small airways disease on quantitative chest CT. In GLUCOLD the signature was associated with decreased response to corticosteroids, irrespective of airway eosinophilic or type 2 inflammation.

CONCLUSION

These data suggest that a gene signature of IL-17 airway epithelial response distinguishes a biologically, radiographically, and clinically distinct COPD subgroup that may benefit from personalized therapy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01969344.

FUNDING

Primary support from the NIH, grants K23HL123778, K12HL11999, U19AI077439, DK072517, U01HL137880, K24HL137013 and R01HL121774 and contracts HHSN268200900013C, HHSN268200900014C, HHSN268200900015C, HHSN268200900016C, HHSN268200900017C, HHSN268200900018C, HHSN268200900019C and HHSN268200900020C.

Clinical phenotypes and outcomes of pulmonary hypertension due to left heart disease: Role of the pre-capillary component

Background

In pulmonary hypertension (PH), both wedge pressure elevation (PAWP) and a precapillary component may affect right ventricular (RV) afterload. These changes may contribute to RV failure and prognosis. We aimed at describing the different haemodynamic phenotypes of patients with PH due to left heart disease (LHD) and at characterizing the impact of pulmonary haemodynamics on RV function and outcome PH-LHD.

Methods

Patients with PH-LHD were compared with treatment-naïve idiopathic/heritable pulmonary arterial hypertension (PAH, n = 35). PH-LHD patients were subdivided in Isolated post-capillary PH (IpcPH: diastolic pressure gradient, DPG<7 mmHg and pulmonary vascular resistance, PVR≤3 WU, n = 37), Combined post- and pre-capillary PH (CpcPH: DPG≥7 mmHg and PVR>3 WU, n = 27), and “intermediate” PH-LHD (either DPG <7 mmHg or PVR ≤3 WU, n = 29).

Results

Despite similar PAWP and cardiac index, haemodynamic severity and prevalence of RV dysfunction increased from IpcPH, to “intermediate” and CpcPH. PVR and DPG (but not compliance, Ca) were linearly correlated with RV dysfunction. CpcPH had worse prognosis (p<0.05) than IpcPH and PAH, but similar to “intermediate” patients. Only NTproBNP and Ca independently predicted survival in PH-LHD.

Conclusions

In PH-LHD, haemodynamic characterization according to DPG and PVR provides important information on disease severity, predisposition to RV failure and prognosis. Patients presenting the CpcPH phenotype appear to have haemodynamic profile closer to PAH but with worse prognosis. In PH-LHD, Ca and NTproBNP were independent predictors of survival.

Doctors on the move: a European case study on the key characteristics of national recertification systems

OBJECTIVES

With increased cross-border movement, ensuring safe and high-quality healthcare has gained primacy. The purpose of recertification is to ensure quality of care through periodically attesting doctors' professional proficiency in their field. Professional migration and facilitated cross-border recognition of qualifications, however, make us question the fitness of national policies for safeguarding patient care and the international accountability of doctors.

DESIGN AND SETTING

We performed document analyses and conducted 19 semistructured interviews to identify and describe key characteristics and effective components of 10 different European recertification systems, each representing one case (collective case study). We subsequently compared these systems to explore similarities and differences in terms of assessment criteria used to determine process quality.

RESULTS

Great variety existed between countries in terms and assessment formats used, targeting cognition, competence and performance (Miller's assessment pyramid). Recertification procedures and requirements also varied significantly, ranging from voluntary participation in professional development modules to the mandatory collection of multiple performance data in a competency-based portfolio. Knowledge assessment was fundamental to recertification in most countries. Another difference concerned the stakeholders involved in the recertification process: while some systems exclusively relied on doctors' self-assessment, others involved multiple stakeholders but rarely included patients in assessment of doctors' professional competence. Differences between systems partly reflected different goals and primary purposes of recertification.

CONCLUSION

Recertification systems differ substantially internationally with regard to the criteria they apply to assess doctors' competence, their aims, requirements, assessment formats and patient involvement. In the light of professional mobility and associated demands for accountability, we recommend that competence assessment includes patients' perspectives, and recertification practices be shared internationally to enhance transparency. This can help facilitate cross-border movement, while guaranteeing high-quality patient care.

Severe community-acquired pneumonia: Characteristics and prognostic factors in ventilated and non-ventilated patients

BACKGROUND

Patients with severe community-acquired pneumonia (SCAP) and life-threatening acute respiratory failure may require invasive mechanical ventilation (IMV). Since use of IMV is often associated with significant morbidity and mortality, we assessed whether patients invasively ventilated would represent a target population for interventions aimed at reducing mortality of SCAP.

METHODS

We prospectively recruited consecutive patients with SCAP for 12 years. We assessed the characteristics and outcomes of patients invasively ventilated at presentation of pneumonia, compared with those without IMV, and determined the influence of risks factors on mortality with a multivariate weighted logistic regression using a propensity score.

RESULTS

Among 3,719 patients hospitalized with CAP, 664 (18%) had criteria for SCAP, and 154 (23%) received IMV at presentation of pneumonia; 198 (30%) presented with septic shock. In 370 (56%) cases SCAP was diagnosed based solely on the presence of 3 or more IDSA/ATS minor criteria. Streptococcus pneumoniae was the main pathogen in both groups. The 30-day mortality was higher in the IMV, compared to non-intubated patients (51, 33%, vs. 94, 18% respectively, p<0·001), and higher than that predicted by APACHE-II score (26%). IMV independently predicted 30-day mortality in multivariate analysis (adjusted odds-ratio 3·54, 95% confidence interval 1·45-8·37, p = 0·006). Other independent predictors of mortality were septic shock, worse hypoxemia and increased serum potassium.

CONCLUSION

Invasive mechanical ventilation independently predicted 30-day mortality in patients with SCAP. Patients invasively ventilated should be considered a different population with higher mortality for future clinical trials on new interventions addressed to improve mortality of SCAP.

Assessing the feasibility of confocal laser endomicroscopy in solitary pulmonary nodules for different part of the lungs, using either 0.6 or 1.4 mm probes

BACKGROUND

Malignant solitary pulmonary nodules (SPN) have become more prevalent, with upper lobes predilection. Probe-based confocal laser endomicroscopy (pCLE) provides in-vivo imaging of SPN. However, the stiffness of the 1mm confocal probe (AlveoFlex) causes difficult accessibility to the upper lobes. A thinner 600μm probe designed for bile duct exploration (CholangioFlex) has the potential to reach the upper lobes.

OBJECTIVES

To examine the accessibility of malignant SPNs in all segments of the lungs using either the 0.6mm or 1.4 mm probe and to assess the quality and inter observer interpretation of SPN confocal imaging obtained from either miniprobes.

METHODS

Radial(r)-EBUS was used to locate and sample the SPN. In-vivo pCLE analysis of the SPN was performed using either CholangioFlex (apical and posterior segments of the upper lobes) or AlveoFlex (other segments) introduced into the guide sheath before sampling. pCLE features were compared between the two probes.

RESULTS

Fourty-eight patients with malignant SPN were included (NCT01931579). The diagnostic accuracy for lung cancer using r-EBUS coupled with pCLE imaging was 79.2%. All the SPNs were successfully explored with either one of the probes (19 and 29 subjects for CholangioFlex and AlveoFlex, respectively). A specific solid pattern in the SPN was found in 30 pCLE explorations. Comparison between the two probes found no differences in the axial fibers thickness, cell size and specific solid pattern in the nodules. Extra-alveolar microvessel size appeared larger using CholangioFlex suggesting less compression effect. The kappa test for interobserver agreement for the identification of solid pattern was 0.74 (p = 0.001).

CONCLUSION

This study demonstrates that pCLE imaging of SPNs is achievable in all segments of both lungs using either the 0.6mm or 1.4mm miniprobe.

Transcriptomic analysis comparing mouse strains with extreme total lung capacities identifies novel candidate genes for pulmonary function

BACKGROUND

Failure to attain peak lung function by early adulthood is a risk factor for chronic lung diseases. Previously, we reported that C3H/HeJ mice have about twice total lung capacity (TLC) compared to JF1/MsJ mice. We identified seven lung function quantitative trait loci (QTL: Lfnq1-Lfnq7) in backcross/intercross mice derived from these inbred strains. We further demonstrated, superoxide dismutase 3, extracellular (Sod3), Kit oncogene (Kit) and secreted phosphoprotein 1 (Spp1) located on these Lfnqs as lung function determinants. Emanating from the concept of early origin of lung disease, we sought to identify novel candidate genes for pulmonary function by investigating lung transcriptome in C3H/HeJ and JF1/MsJ mice at the completion of embryonic development, bulk alveolar formation and maturity.

METHODS

Design-based stereological analysis was performed to study lung structure in C3H/HeJ and JF1/MsJ mice. Microarray was used for lung transcriptomic analysis [embryonic day 18, postnatal days 28, 70]. Quantitative real time polymerase chain reaction (qRT-PCR), western blot and immunohistochemical analysis were used to confirm selected differences.

RESULTS

Stereological analysis revealed decreased alveolar number density, elastin to collagen ratio and increased mean alveolar volume in C3H/HeJ mice compared to JF1/MsJ. Gene ontology term "extracellular region" was enriched among the decreased JF1/MsJ transcripts. Candidate genes identified using the expression-QTL strategy include: ATP-binding cassette, sub-family G (WHITE), member 1 (Abcg1), formyl peptide receptor 1 (Fpr1), gamma-aminobutyric acid (GABA) B receptor, 1 (Gabbr1); histocompatibility 2 genes: class II antigen E beta (H2-Eb1), D region locus 1 (H2-D1), and Q region locus 4 (H2-Q4); leucine rich repeat containing 6 (testis) (Lrrc6), radial spoke head 1 homolog (Rsph1), and surfactant associated 2 (Sfta2). Noteworthy genes selected as candidates for their consistent expression include: Wnt inhibitor factor 1 (Wif1), follistatin (Fst), chitinase-like 1 (Chil1), and Chil3.

CONCLUSIONS

Comparison of late embryonic, adolescent and adult lung transcript profiles between mouse strains with extreme TLCs lead to the identification of candidate genes for pulmonary function that has not been reported earlier. Further mechanistic investigations are warranted to elucidate their mode of action in determining lung function.

Treatment with macrolides and glucocorticosteroids in severe community-acquired pneumonia: A post-hoc exploratory analysis of a randomized controlled trial

BACKGROUND

Systemic corticosteroids have anti-inflammatory effects, whereas macrolides also have immunomodulatory activity in addition to their primary antimicrobial actions. We aimed to evaluate the potential interaction effect between corticosteroids and macrolides on the systemic inflammatory response in patients with severe community-acquired pneumonia to determine if combining these two immunomodulating agents was harmful, or possibly beneficial.

METHODS

We performed a post-hoc exploratory analysis of a randomized clinical trial conducted in three tertiary hospitals in Spain. This trial included patients with severe community-acquired pneumonia with high inflammatory response (C-reactive protein [CRP] >15 mg/dL) who were randomized to receive methylprednisolone 0.5 mg/kg/tpd or placebo. The choice of antibiotic treatment was at the physician's discretion. One hundred and six patients were classified into four groups according to antimicrobial therapy combination (β-lactam plus macrolide or β-lactam plus fluoroquinolone) and corticosteroid arm (placebo or corticosteroids). The primary outcome was treatment failure (composite outcome of early treatment failure, or of late treatment failure, or of both early and late treatment failure).

RESULTS

The methylprednisolone with β-lactam plus macrolide group had more elderly patients, with comorbidities, and higher pneumonia severity index (PSI) risk class V, but a lower proportion of intensive care unit admission, compared to the other groups. We found non differences in treatment failure between groups (overall p = 0.374); however, a significant difference in late treatment failure was observed (4 patients in the placebo with β-lactam plus macrolide group (31%) vs. 9 patients in the placebo with β-lactam plus fluoroquinolone group (24%) vs. 0 patients in the methylprednisolone with β-lactam plus macrolide group (0%) vs. 2 patients [5%] in the methylprednisolone with β-lactam plus fluoroquinolone group overall p = 0.009). We found a significant difference for In-hospital mortality in the per protocol population (overall p = 0.01). We did not find significant differences in treatment failure, early or late; or In-hospital mortality after adjusting for severity (PSI), year and centre of enrolment.

CONCLUSIONS

In this exploratory analysis, we observed that the glucocorticosteroids and macrolides combination had no statistically significant association with main clinical outcomes compared with other combinations in patients with severe community acquired pneumonia and a high inflammatory response after taking account potential confounders.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00908713.

Identification of MiR-21-5p as a Functional Regulator of Mesothelin Expression Using MicroRNA Capture Affinity Coupled with Next Generation Sequencing

MicroRNAs (miRNAs) are small non-coding RNAs that regulate mRNA expression mainly by silencing target transcripts via binding to miRNA recognition elements (MREs) in the 3'untranslated region (3'UTR). The identification of bona fide targets is challenging for researchers working on the functional aspect of miRNAs. Recently, we developed a method (miR-CATCH) based on biotinylated DNA antisense oligonucleotides that capture the mRNA of interest and facilitates the characterisation of miRNAs::mRNA interactions in a physiological cellular context. Here, the miR-CATCH technique was applied to the mesothelin (MSLN) gene and coupled with next generation sequencing (NGS), to identify miRNAs that regulate MSLN mRNA and that may be responsible for its increased protein levels found in malignant pleural mesothelioma (MPM). Biotinylated MSLN oligos were employed to isolate miRNA::MSLN mRNA complexes from a normal cell line (Met-5A) which expresses low levels of MSLN. MiRNAs targeting the MSLN mRNA were identified by NGS and miR-21-5p and miR-100-5p were selected for further validation analyses. MiR-21-5p was shown to be able to modulate MSLN expression in miRNA mimic experiments in a panel of malignant and non-malignant cell lines. Further miRNA inhibitor experiments and luciferase assays in Mero-14 cells validated miR-21-5p as a true regulator of MSLN. Moreover, in vitro experiments showed that treatment with miR-21-5p mimic reduced proliferation of MPM cell lines. Altogether, this work shows that the miR-CATCH technique, coupled with NGS and in vitro validation, represents a reliable method to identify native miRNA::mRNA interactions. MiR-21-5p is suggested as novel regulator of MSLN with a possible functional role in cellular growth.