The Chemerin/ChemR23 System Does Not Affect the Pro-Inflammatory Response of Mouse and Human Macrophages Ex Vivo

Macrophages constitute a major component of innate immunity and play an essential role in defense mechanisms against external aggressions and in inflammatory responses. Chemerin, a chemoattractant protein, is generated in inflammatory conditions, and recruits cells expressing the G protein-coupled receptor ChemR23, including macrophages. Chemerin was initially expected to behave as a pro-inflammatory agent. However, recent data described more complex activities that are either pro- or anti-inflammatory, according to the disease model investigated. In the present study, peritoneal macrophages were generated from WT or ChemR23−/− mice, stimulated with lipopolyssaccharide in combination or not with IFN-γ and the production of pro- (TNF-α, IL-1β and IL-6) and anti-inflammatory (IL-10) cytokines was evaluated using qRT-PCR and ELISA. Human macrophages generated from peripheral blood monocytes were also tested in parallel. Peritoneal macrophages from WT mice, recruited by thioglycolate or polyacrylamide beads, functionally expressed ChemR23, as assessed by flow cytometry, binding and chemotaxis assays. However, chemerin had no effect on the strong upregulation of cytokine release by these cells upon stimulation by LPS or LPS/IFN-γ, whatever the concentration tested. Similar data were obtained with human macrophages. In conclusion, our results rule out the direct anti-inflammatory effect of chemerin on macrophages ex vivo, described previously in the literature, despite the expression of a functional ChemR23 receptor in these cells

Early lineage restriction in temporally distinct populations of Mesp1 progenitors during mammalian heart development.

Cardiac development arises from two sources of mesoderm progenitors, the first heart field (FHF) and the second (SHF). Mesp1 has been proposed to mark the most primitive multipotent cardiac progenitors common for both heart fields. Here, using clonal analysis of the earliest prospective cardiovascular progenitors in a temporally controlled manner during early gastrulation, we found that Mesp1 progenitors consist of two temporally distinct pools of progenitors restricted to either the FHF or the SHF. FHF progenitors were unipotent, whereas SHF progenitors were either unipotent or bipotent. Microarray and single-cell PCR with reverse transcription analysis of Mesp1 progenitors revealed the existence of molecularly distinct populations of Mesp1 progenitors, consistent with their lineage and regional contribution. Together, these results provide evidence that heart development arises from distinct populations of unipotent and bipotent cardiac progenitors that independently express Mesp1 at different time points during their specification, revealing that the regional segregation and lineage restriction of cardiac progenitors occur very early during gastrulation.This is the author's accepted manuscript and will be under embargo until the 24th of February 2015. The final version is published by NPG in Nature Cell Biology here: http://www.nature.com/ncb/journal/v16/n9/full/ncb3024.html

Idiopathic pulmonary fibrosis: Best practice in monitoring and managing a relentless fibrotic disease

Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial lung disease that is, by definition, progressive. Progression of IPF is reflected by a decline in lung function, worsening of dyspnea and exercise capacity, and deterioration in health-related quality of life. In the short term, the course of disease for an individual patient is impossible to predict. A period of relative stability in forced vital capacity (FVC) does not mean that FVC will remain stable in the near future. Frequent monitoring using multiple assessments, not limited to pulmonary function tests, is important to evaluate disease progression in individual patients and ensure that patients are offered appropriate care. Optimal management of IPF requires a multidimensional approach, including both pharmacological therapy to slow decline in lung function and supportive care to preserve patients' quality of life

Nintedanib for Systemic Sclerosis-Associated Interstitial Lung Disease

BACKGROUND: Interstitial lung disease (ILD) is a common manifestation of systemic sclerosis and a leading cause of systemic sclerosis-related death. Nintedanib, a tyrosine kinase inhibitor, has been shown to have antifibrotic and antiinflammatory effects in preclinical models of systemic sclerosis and ILD. METHODS: We conducted a randomized, double-blind, placebo-controlled trial to investigate the efficacy and safety of nintedanib in patients with ILD associated with systemic sclerosis. Patients who had systemic sclerosis with an onset of the first non-Raynaud's symptom within the past 7 years and a high-resolution computed tomographic scan that showed fibrosis affecting at least 10% of the lungs were randomly assigned, in a 1:1 ratio, to receive 150 mg of nintedanib, administered orally twice daily, or placebo. The primary end point was the annual rate of decline in forced vital capacity (FVC), assessed over a 52-week period. Key secondary end points were absolute changes from baseline in the modified Rodnan skin score and in the total score on the St. George's Respiratory Questionnaire (SGRQ) at week 52. RESULTS: A total of 576 patients received at least one dose of nintedanib or placebo; 51.9% had diffuse cutaneous systemic sclerosis, and 48.4% were receiving mycophenolate at baseline. In the primary end-point analysis, the adjusted annual rate of change in FVC was 1252.4 ml per year in the nintedanib group and 1293.3 ml per year in the placebo group (difference, 41.0 ml per year; 95% confidence interval [CI], 2.9 to 79.0; P=0.04). Sensitivity analyses based on multiple imputation for missing data yielded P values for the primary end point ranging from 0.06 to 0.10. The change from baseline in the modified Rodnan skin score and the total score on the SGRQ at week 52 did not differ significantly between the trial groups, with differences of 120.21 (95% CI, 120.94 to 0.53; P=0.58) and 1.69 (95% CI, 120.73 to 4.12 [not adjusted for multiple comparisons]), respectively. Diarrhea, the most common adverse event, was reported in 75.7% of the patients in the nintedanib group and in 31.6% of those in the placebo group. CONCLUSIONS: Among patients with ILD associated with systemic sclerosis, the annual rate of decline in FVC was lower with nintedanib than with placebo; no clinical benefit of nintedanib was observed for other manifestations of systemic sclerosis. The adverse-event profile of nintedanib observed in this trial was similar to that observed in patients with idiopathic pulmonary fibrosis; gastrointestinal adverse events, including diarrhea, were more common with nintedanib than with placebo

Resolution of inflammation: a new therapeutic frontier

Dysregulated inflammation is a central pathological process in diverse disease states. Traditionally, therapeutic approaches have sought to modulate the pro- or anti-inflammatory limbs of inflammation, with mixed success. However, insight into the pathways by which inflammation is resolved has highlighted novel opportunities to pharmacologically manipulate these processes — a strategy that might represent a complementary (and perhaps even superior) therapeutic approach. This Review discusses the state of the art in the biology of resolution of inflammation, highlighting the opportunities and challenges for translational research in this field

Genetic Basis of Myocarditis: Myth or Reality?

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Assessment of 18F-FDG uptake in idiopathic pulmonary fibrosis: influence of lung density changes

Abstract Background Idiopathic Pulmonary Fibrosis (IPF) is a progressive and irreversible disease leading to terminal respiratory insufficiency. Fluorodeoxyglucose ([18F]-FDG) PET/CT has been proposed to track the activity of the disease. However, IPF is characterized by regional changes in lung density that affects the FDG uptake, a factor generally not taken into account in previous studies. In this work, we studied the relationship between severity of IPF and lung uptake of [18F]-FDG, evaluated by mean and maximum standardized uptake value (SUV), corrected (SUVmean-corr; SUVmax-corr) and uncorrected for lung density (SUVmean-uncorr; SUVmax-uncorr). Methods [18F]-FDG PET/CT was performed in 31 IPF patients between 2013 and 2017. Lung density was determined on CT. SUV values were correlated with lung function tests, carbon monoxide diffusion (DLCO) and 6-min walking test (6MWT) at baseline and at 1 year. Correlation with the GAP index, a well-validated prognostic score in IPF, was also determined. Results At baseline, SUVmean-uncorr was highly correlated with lung density (r = 0.755; p <  0.001). SUVmean-uncorr and lung density were correlated with lung function tests (vital capacity (VC): p = 0.013 and p = 0.003; forced vital capacity (FVC): p = 0.004 and p = 0.001; total lung capacity (TLC): p = 0.001 and p = 0.001, respectively), while SUVmean-corr was not (VC: p = 0.733; FVC: p = 0.667; TLC: p = 0.382). Interestingly, SUVmean-corr was significantly higher in patients with a GAP index of 3 (p = 0.005), and negatively correlated with DLCO (r = − 0.398; p = 0.026) and desaturation during the 6MWT (r = − 0.401; p = 0.024). But no correlation was found with changes in lung function tests, walk distance and DLCO at 1 year. Conclusion To evaluate the role of ([18F]-FDG) PET/CT in IPF, correction for lung density appears necessary. As suggested by the correlation with DLCO, density-corrected SUV seems related to the intrinsic disease activity and particularly to the integrity of the alveolar-capillary barrier. However, ([18F]-FDG) PET/CT has probably a limited prognostic value as no correlation was found between SUVmean-corr and the clinical evolution at 1 year. Further studies with a longer follow-up are warranted