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Background: Persistence of myofibroblasts is believed to contribute to the development of fibrosis in idiopathic pulmonary fibrosis (IPF). Transforming growth factor beta1 (TGFbeta1) irreversibly converts fibroblasts into pathological myofibroblasts, which express smooth muscle alpha-actin (alpha-SMA) and produce extracellular matrix proteins, such as procollagen I (alpha1). Reactive oxygen species produced by NADPH oxidases (NOXs) have been shown to regulate cell differentiation. It was hypothesised that NOX could be expressed in parenchymal pulmonary fibroblasts and could mediate TGFbeta1-stimulated conversion of fibroblasts into myofibroblasts.Methods: Fibroblasts were cultured from the lung of nine controls and eight patients with IPF. NOX4, alpha-SMA and procollagen I (alpha1) mRNA and protein expression, reactive oxygen species production and Smad2/3 phosphorylation were quantified, in the absence and in the presence of incubation with TGFbeta1. Migration of platelet-derived growth factor (PDGF)-induced fibroblasts was also assessed.Results: It was found that (1) NOX4 mRNA and protein expression was upregulated in pulmonary fibroblasts from patients with IPF and correlated with mRNA expression of alpha-SMA and procollagen I (alpha1) mRNA; (2) TGFbeta1 upregulated NOX4, alpha-SMA and procollagen I (alpha1) expression in control and IPF fibroblasts; (3) the change in alpha-SMA and procollagen I (alpha1) expression in response to TGFbeta1 was inhibited by antioxidants and by a NOX4 small interfering RNA (siRNA); (4) NOX4 modulated alpha-SMA and procollagen I (alpha1) expression by controlling activation of Smad2/3; and (5) NOX4 modulated PDGF-induced fibroblast migration.Conclusion: NOX4 is critical for modulation of the pulmonary myofibroblast phenotype in IPF, probably by modulating the response to TGFbeta1 and PDGF. [ABSTRACT FROM AUTHOR]

Background: All-trans retinoic acid (ATRA) stimulates elastin synthesis by lung fibroblasts and induces alveolar regeneration in animal models of pulmonary emphysema. However, ATRA treatment has had disappointing results in human emphysema. It was hypothesised that a defect in the ATRA signalling pathway contributes to the defect of alveolar repair in the human emphysematous lung. Methods: Fibroblasts were cultured from the lung of 10 control subjects and eight patients with emphysema. Elastin and retinoic acid receptor (RAR)-β mRNAs were measured in those cells in the presence of incremental concentrations of ATRA. RARs, retinoic X receptors (RXRs) and cellular retinoic acid binding protein (CRABP) 1 and 2 mRNAs were measured as well as CRABP2 protein content. The effect of CRABP2 silencing on elastin and RAR-β expression in response to ATRA was measured in MRC5 lung fibroblasts. Results: ATRA at 10-9 M and 10-8 M increased median elastin mRNA expression by 182% and 126% in control but not in emphysema fibroblasts. RAR-13 mRNA expression was induced by ATRA in control as well as emphysema fibroblasts. RARs, RXRs and CRABP1 mRNAs were similarly expressed in control and emphysema fibroblasts while CRABP2 mRNA and protein were lower in emphysema fibroblasts. CRABP2 silencing abrogated the induction of elastin but not RAR-13 expression by ATRA in MRC5 fibroblasts. Conclusion: Pulmonary emphysema fibroblasts fail to express elastin under ATRA stimulation. CRABP2, which is necessary for elastin induction by ATRA in MRC-5 cells, is expressed at low levels in emphysema fibroblasts. This alteration in the retinoic acid signalling pathway in lung fibroblasts may contribute to the defect of alveolar repair in human pulmonary emphysema. These results are the first demonstration of the involvement of CRABP2 in elastin expression. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress, resulting from the increased oxidative burden and decreased level of antioxidant proteins, plays a role in the pathophysiology of smoking-related pulmonary emphysema. Expression of several antioxidant proteins, such as heme oxygenase-1 (HO-1), glutathione peroxidase 2 (GPX2) and NAD(P)H:quinone oxidoreductase 1 (NQO1), results from an equilibrium created by positive or negative regulation by the transcription factors Nrf2, Keap1 and Bach1, respectively. However, whether the expression of these transcription factors is altered in emphysema and could account for decreased expression of antioxidant proteins is not known. A study was undertaken to investigate the expression and subcellular localisation of Nrf2, Keap1 and Bach1 as potential regulators of HO-1, GPX2 and NQO1 in alveolar macrophages, a key cell in oxidative stress, in lung surgical specimens from non-smokers without emphysema and smokers with and without emphysema.Methods and Results: Western blot, immunohistochemical and laser scanning confocal analysis revealed that the Nrf2 protein level decreased significantly in whole lung tissue and alveolar macrophages (cytosol and nucleus) in patients with emphysema compared with those without emphysema. Conversely, Bach1 and Keap1 levels were increased in patients with emphysema. These modifications were associated with a parallel decrease in the expression of HO-1, GPX2 and NQO1 at the cellular level, which was inversely correlated with airway obstruction and distension indexes, and increased macrophage expression of the lipid peroxidation product 4-hydroxy-2-nonenal. Silencing RNA experiments in vitro in THP-1 cells were performed to confirm the cause-effect relation between the loss of Nrf2 and the decrease in HO-1, NQO1 and GPX2 expression. Nrf2/Keap1-Bach1 equilibrium was altered in alveolar macrophages in pulmonary emphysema, which points to a decreased stress response phenotype.Conclusions: This finding opens a new view of the pathophysiology of emphysema and could provide the basis for new therapeutic approaches based on preservation and/or restoration of such equilibrium. [ABSTRACT FROM AUTHOR]

Background and aim: Somatostatin analogues may have antifibrotic properties in the lung. The aim of this study was to evaluate the expression of the five somatostatin receptors sst1 to sst5 in normal and fibrotic mouse lung and the action of SOM230 (pasireotide), a new somatostatin analogue with a long half-life, in bleomycin induced lung fibrosis and in human lung fibroblasts in vitro. Methods: After intratracheal injection of bleomycin, C57BI6 male mice received one daily subcutaneous injection of SOM230 or saline. The lungs were evaluated on days 3, 7 and 14 after administration of bleomycin. Results: We found that all somatostatin receptors were expressed in the normal mouse lung. The sst2 receptor mRNA expression was increased after bleomycin. SOM230 improved mice survival (69% vs 44%; p = 0.024), reduced lung collagen content at day 14 and decreased lung collagen-1 mRNA at day 7. SOM230 reduced bronchoalveolar lavage inflammatory cell influx at day 3, decreased lung connective tissue growth factor mRNA and transforming growth factor (TGF) β mRNA and increased lung hepatocyte growth factor and keratinocyte growth factor mRNA. The sst2 receptor was strongly expressed in the human lung (normal or fibrotic), particularly by fibroblasts. In vitro, SOM230 reduced BrdU incorporation by control human lung fibroblasts cultured under basal conditions or with TGFβ, and reduced alpha-1 collagen-1 mRNA expression in TGFβ stimulated fibroblasts. Conclusion: We conclude that SOM230 attenuates bleomycin induced pulmonary fibrosis in mice and human lung fibroblasts activation. This study points to a potential new approach for treating pulmonary fibrotic disorders. [ABSTRACT FROM AUTHOR]

Aim: A multicentre retrospective study was undertaken to examine patients with interstitial lung disease (ILD) with the initial clinical manifestation of an anti-synthetase syndrome (anti-Jo-1 antibodies), and to analyse the characteristics and long-term outcome of these patients according to their clinical presentation (acute or gradual onset), treatment and adverse events related to treatment. Methods: 32 patients, 15(47%) presenting with acute onset and associated respiratory insufficiency (group A) and 17(53%) with gradual onset (group G) were examined. Myositis was diagnosed at admission in only 31% of cases and was observed during follow-up in 56% of cases, but the prevalence did not differ between the two groups. Results: Fever and radiological patterns including diffuse patchy ground-glass opacities, basal irregular lines and consolidation on high-resolution CT scan were more frequent in group A than in group 8. More patients in group 8 had neutrophils in the bronchoalveolar lavage fluid and autoantibodies other than anti-Jo-1 (rheumatoid factor, anti SSa/SSb) than in group A. The percentage of patients in whom the ILD improved at 3 months was significantly higher in group A than in group 8 (13/15 vs 9/17; p = 0.006). In contrast, after 12 months, most patients with ILD progression were in group A and were treated with corticosteroids alone. A combination of corticosteroids and an immunosuppressive drug was required in most cases (84%) at the end of the follow-up period. Severe adverse effects of treatment were observed and varicella zoster virus infection was frequent. Conclusions: Early testing for anti-synthetase antibodies, particularly anti-Jo-1, and creatine kinase determination are useful procedures in patients presenting with ILD. Treatment with corticosteroids and immunosuppressive drugs is required in most patients. At the end of the study, around two-thirds of patients had stable ILD while the other third had disease progression with respiratory insufficiency. [ABSTRACT FROM AUTHOR]

Background: The overexpression of interferon (IFN)γ or interleukin (IL)-13 in the adult murine lung induces the development of changes that mirror human lung emphysema. Methods: IL-13 and IFNγ expression was determined in lung samples from five groups of patients: severe emphysema without α1-antitrypsin deficiency (SE+, n =10); severe emphysema with α1-antitrypsin deficiency (SE-, n = 5); mild localised emphysema (ME, n = 8); non-emphysema smokers (NE-S, n = 9), and non-emphysema non-smokers (NE-NS, n =11). Lung 11-13 and IFN7 mRNA were analysed by RI- PCR. Lung concentrations of IL- 13 protein were assessed by ELISA. Results: The expression of IFN7 mRNA was similar in patients with or without emphysema. IL-i 3 mRNA was markedly decreased in the SE+ group compared with the SE- (p =0.04), ME (p =0.02), and non- emphysema groups (p = 0.01). IL-i 3 mRNA correlated with forced expiratory volume in 1 second (r= 0.5, p = 0.04) and arterial oxygen tension (r= 0.45, p = 0.03) in emphysema patients. In contrast to the non- emphysematous lung, IL- 13 protein was below the detection limit of the assay in most emphysematous lung homogenates. Conclusion: The lung IL-i 3 content is reduced in patients with severe emphysema without α1-antitrypsin deficiency. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to a previously published article on an international registry for idiopathic pulmonary fibrosis.

Objectives: Interstitial lung disease (ILD) is a severe extra-articular manifestation of rheumatoid arthritis (RA). The objectives of this study were to estimate mortality rate in patients with RA-ILD and identify factors affecting mortality., Methods: Data from a French national claims database (Système National des Données de Santé) from 2013 to 2018 were analysed. Adults with an RA diagnosis (International Classification of Diseases (ICD)-10 codes M05, M06.0, M06.8 and M06.9) were included. ILD diagnosis was defined with ICD-10 code J84. Mortality rates were compared between patients with RA with and without ILD, using Cox proportional hazards regression, after matching 1:1 for age, sex, age at RA-ILD onset and RA duration., Results: Among 173 132 patients with RA, 4330 (3%) also had ILD (RA-ILD). After matching, RA-ILD was associated with an increased mortality rate (HR 3.4, 95% CI 3.1 to 3.9). The HR for mortality was greater for: patients aged <75 years (HR 4.8, 95% CI 3.9 to 5.9) versus ≥75 years (HR 3.0, 95% CI 2.6 to 3.5); patients with ILD onset occurring before RA onset (HR 8.4, 95% CI 5.5 to 13.0) versus ILD onset occurring after RA onset (HR 2.9, 95% CI 2.6 to 3.3); and men (HR 5.2, 95% CI 4.4 to 6.2) versus women (HR 3.6, 95% CI 3.0 to 4.2)., Conclusion: In this nationwide cohort study, RA-ILD was associated with increased mortality rate (vs in patients with RA without ILD), notably for those aged <75 years, those whose ILD preceded RA onset and men., Competing Interests: Competing interests: PA-J has received grant/research support from AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, Medac, Novartis, Roche Chugai and Societe Francaise de Rhumatologie; and consultancy fees from Bristol Myers Squibb. LW has received consultancy fees from Boehringer Ingelheim, Bristol Myers Squibb, Roche and Sanofi. SO has received consultancy fees from AbbVie, Bristol Myers Squibb, Eli Lilly, Merck Sharp & Dohme, Novartis, Roche-Chugai, SOBI and UCB. GD has received consultancy fees from Bristol Myers Squibb. JZ and VV-M are employees of and shareholders in Bristol Myers Squibb. R-MF has received speakers bureau fees from AbbVie, Bristol Myers Squibb, Eli Lilly, Janssen, Medac, Merck Sharp & Dohme, Novartis, Pfizer and Roche-Chugai; and grant/research support from Amgen, Janssen, Novartis and Pfizer. BC has received consultancy fees from Apellis, AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, Novartis, Roche and Sanofi; and grant/research support from Boehringer Ingelheim, Bristol Myers Squibb and Roche. PD has received consultancy fees from Boehringer Ingelheim, Bristol Myers Squibb, Chugai, Eli Lilly, Medac, Novartis, Pfizer and Sanofi; and grant/research support from Bristol Myers Squibb, GlaxoSmithKline and Pfizer., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The European League Against Rheumatism recommendations for the management of antineutrophil cytoplasmic antibody-associated vasculitis have been recently published. Unique to recommendation development, they were also voted on by members of a learned society. This paper explores the wider validity of the recommendations among people who self-identify as clinicians caring for patients with vasculitis. In addition to the task force, a learned society (European Vasculitis Society-EUVAS) was invited, through online survey, to rate independently the strength of evidence of each recommendation to obtain an indication of the agreement among the final target audience and ultimate end-users of the recommendations. The survey took place in June 2015. Of the 158 EUVAS members surveyed, there were 88 responses (55.7%). There was a large degree of agreement in the voting patterns between EUVAS survey participants and task force members. Notable exceptions were lower grades for the recommendation of the use of rituximab for remission induction in patients with eosinophilic granulomatosis with polyangiitis and for methotrexate and mycophenolate mofetil as remission maintenance agents in patients with granulomatosis with polyangiitis/microscopic polyangiitis by EUVAS members. These results are encouraging and suggest that the voting patterns of the task force are representative of the wider vasculitis community. We recommend future recommendations adopt this approach for data/expert-based treatment guidelines, especially for multisystem diseases., Competing Interests: Competing interests: None declared.