The genetics of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a significant cause of global morbidity and mortality. Previous studies have shown that COPD aggregates in families, suggesting a genetic predisposition to airflow obstruction. Many candidate genes have been assessed, but the data are often conflicting. We review the genetic factors that predispose smokers to COPD and highlight the future role of genomic scans in identifying novel susceptibility genes.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Progressive myoclonus epilepsy associated with neuroserpin inclusion bodies (neuroserpinosis)

Familial encephalopathy with neuroserpin inclusion bodies (FENIB) is a conformational proteinopathy characterised by neuronal inclusion bodies composed of the serine protease inhibitor (SERPIN), neuroserpin. Presenting clinically as a familial dementia-epilepsy syndrome, the molecular mechanism of the pathogenic abnormalities in neuroserpin has been characterised at atomic resolution. There is a remarkable genotype-phenotype correlation between the degree of molecular destabilisation of the several variants of the neuroserpin protein, their propensity to self-associate and the age of onset of the dementia-epilepsy complex. As with other serpinopathies there appears to be a mix of cell-autonomous toxicity, due to neuronal accumulation of neuroserpin, and non-cell autonomous toxicity, caused by loss of protease inhibition, in this case the dysregulated protease is likely to be tissue plasminogen activator (tPA). FENIB should be considered in cases of progressive myoclonic epilepsy and dementia particularly where there is family history of neuropsychiatric disease

An antibody raised against a pathogenic serpin variant induces mutant-like behaviour in the wild-type protein.

A monoclonal antibody (mAb) that binds to a transient intermediate may act as a catalyst for the corresponding reaction; here we show this principle can extend on a macro-molecular scale to the induction of mutant-like oligomerisation in a wild-type protein. Using the common, pathogenic Glu342Lys (Z) variant of α1-antitrypsin as antigen - whose native state is susceptible to the formation of a proto-oligomeric intermediate - we have produced a mAb (5E3) that increases the rate of oligomerisation of the wild-type (M) variant. Employing ELISA, gel shift, thermal stability and FRET time-course experiments, we show that mAb5E3 does not bind to the native state of α1-antitrypsin, but recognises a cryptic epitope in the vicinity of the post-helix A loop and strand 4C that is revealed upon transition to the polymerisation intermediate, and which persists in the ensuing oligomer. This epitope is not shared by loop-inserted monomeric conformations. We show the increased amenity to polymerisation by either the pathogenic Glu342Lys mutation or the binding of mAb5E3 occurs without affecting energetic barrier to polymerisation. As mAb5E3 also does not alter the relative stability of the monomer to intermediate, it acts in a manner similar to the Glu342Lys mutation, by facilitating the conformational interchange between these two states

Limitations to Contingency Measures: Reflections from COVID-19 Surges in the UK

Alfandre et al. (2021) helpfully outlines the case for attending to contingency planning as well as to crisis measures during a pandemic. The authors provides a helpful framework for reflecting on the experiences of healthcare staff during COVID-19 to develop a more robust contingency phase. We do so, ourselves, in the context of the United Kingdom, particularly London where the prevalence of COVID-19 stretched resources despite considerable and continuing efforts to increase capacity as the depth of the crisis was understood. Recognizing the inevitable increase in cases once community transmission took hold, the UK government’s strategy was to keep case load manageably within the capacity of the National Health Service (NHS). All public health interventions were modeled and planned accordingly with insufficient regard to contingencies

Calcium signalling in mammalian cell lines expressing wild type and mutant human α1-Antitrypsin

A possible role for calcium signalling in the autosomal dominant form of dementia, familial encephalopathy with neuroserpin inclusion bodies (FENIB), has been proposed, which may point towards a mechanism by which cells could sense and respond to the accumulation of mutant serpin polymers in the endoplasmic reticulum (ER). We therefore explored possible defects in Ca2+-signalling, which may contribute to the pathology associated with another serpinopathy, α1-antitrypsin (AAT) deficiency. Using CHO K1 cell lines stably expressing a wild type human AAT (MAAT) and a disease-causing polymer-forming variant (ZAAT) and the truncated variant (NHK AAT), we measured basal intracellular free Ca2+, its responses to thapsigargin (TG), an ER Ca2+-ATPase blocker, and store-operated Ca2+-entry (SOCE). Our fura2 based Ca2+ measurements detected no differences between these 3 parameters in cell lines expressing MAAT and cell lines expressing ZAAT and NHK AAT mutants. Thus, in our cell-based models of α1-antitrypsin (AAT) deficiency, unlike the case for FENIB, we were unable to detect defects in calcium signalling

Once-Daily Triple Therapy in Patients with COPD: Patient-Reported Symptoms and Quality of Life.

INTRODUCTION: Directly recorded patient experience of symptoms and health-related quality of life (HRQoL) can complement lung function and exacerbation rate data in chronic obstructive pulmonary disease (COPD) clinical studies. The FULFIL study recorded daily symptoms and activity limitation together with additional patient-reported outcomes of dyspnea and HRQoL, as part of the prespecified analyses. FULFIL co-primary endpoint data have been previously reported. METHODS: FULFIL was a phase III, 24-week, randomized, double-blind, double-dummy, multicenter study comparing once-daily single inhaler triple therapy [fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI)] 100 µg/62.5 µg/25 µg with twice-daily inhaled corticosteroid/long-acting β2-agonist therapy [budesonide/formoterol (BUD/FOR)] 400 µg/12 µg in patients with symptomatic COPD at risk of exacerbations. A subset participated for 52 weeks. Patient-reported assessments were: Evaluating Respiratory Symptoms in COPD™ (E-RS: COPD), St George's Respiratory Questionnaire (SGRQ) for COPD, COPD Assessment Test (CAT), baseline and transitional dyspnea indices (TDI) and daily and global anchor questions for activity limitation. RESULTS: FF/UMEC/VI showed greater reductions from baseline in 4-weekly mean E-RS: COPD total and all subscale scores compared with BUD/FOR; differences were statistically significant (P < 0.05) at each time period. FF/UMEC/VI also demonstrated greater improvements from baseline at weeks 4 and 24 in SGRQ domain scores and TDI focal score compared with BUD/FOR. At weeks 4 and 24, improvements greater than the minimal clinically important difference from baseline were observed in CAT score with FF/UMEC/VI, but not BUD/FOR; differences were statistically significant (P ≤ 0.003). CONCLUSION: These findings demonstrate sustained daily symptom and HRQoL benefits of FF/UMEC/VI versus BUD/FOR. The inclusion of the CAT may provide data that are readily generalizable to everyday clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT02345161. FUNDING: GSK

Non-invasive testing for liver pathology in alpha-1 antitrypsin deficiency

BACKGROUND: Many patients with alpha-1 antitrypsin deficiency (A1ATD) receive care in respiratory clinics without access to specialist hepatology expertise. Liver disease can develop asymptomatically, and non-invasive markers of fibrosis may help identify patients who require definitive assessment with liver biopsy. We evaluated the utility of non-invasive markers of liver fibrosis in A1ATD to guide testing in settings without ready access to hepatology expertise. METHODS: Patients attending the London A1ATD service undergo assessment using blood tests to calculate the 'APRI' and 'FIB-4' score, liver ultrasound and Fibroscan. Liver biopsy is offered to patients who have abnormal liver function tests with abnormal liver ultrasound and/or liver stiffness >6 kPa on Fibroscan. Liver biopsies were assessed for the presence of A1AT, steatosis, fibrosis and inflammation. RESULTS: 75 patients with A1ATD had results for analysis, 56% were female, age 16-82 years. 75% of patients had Fibroscan 8 kPa. There was a significant correlation between FIB-4 and Fibroscan (r=0.244, p=0.035). Fibroscan >6 kPa corresponded to a FIB-4 score of >1.26. However, FIB-4 >1.26 had poor sensitivity (47%), specificity (32%) and positive-predictive value (PPV; 36%) to identify Fibroscan >6 kPa. The negative-predictive value (NPV) was stronger at 81%. APRI data were similar. Twelve patients underwent liver biopsy, with 11 reports available for analysis. Six had FIB-4 scores<1.26 and five had Fibroscan of <6 kPa. A1AT was present in 64% of biopsies, steatosis in 82%, mild fibrosis in 36%, moderate fibrosis in 9% and severe fibrosis in 9%. CONCLUSION: A combination of liver ultrasound and non-invasive fibrosis tests can help identify patients with A1ATD liver injury. However, APRI and FIB-4 scores alone had poor sensitivity and specificity to justify use as an independent tool for liver pathology in A1ATD