This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Objectives: The aim of this study was to explore the anti-inflammatory properties of roflumilast in a human model of segmental bronchial endotoxin challenge. A c c e p t e d m a n u s c r i p tMethods: In a randomized, placebo-controlled, double-blind, single-center parallelgroup study, 37 healthy subjects of either sex were treated for 28 days with either oral roflumilast 500 µg once daily or placebo. At Day 29, a baseline bronchoalveolar lavage was performed, followed by segmental endotoxin challenge (4 ng/kg) and saline control challenge.After 24 h, bronchoalveolar lavage fluid was sampled from the challenged segments and cells were counted and differentiated.Results: After endotoxin challenge, influx of total cells (difference from baseline) in bronchoalveolar lavage of roflumilast treated subjects was 36% lower than with placebo (p=0.02). Correspondingly, the influx of neutrophils and eosinophils of roflumilast treated subjects was 39% (p=0.02) and 74% (p=0.01) lower than with placebo, respectively. In contrast, endotoxin-induced influx of monocytes was not different between roflumilast and placebo treated subjects. No significant differences existed between the groups pertaining to endotoxin-induced influx of macrophages and lymphocytes. Roflumilast was well tolerated.No unexpected or serious treatment-emergent signs and symptoms were observed.Conclusions: Roflumilast attenuated the endotoxin-induced influx of neutrophils and eosinophils into the airways. This study demonstrates the anti-inflammatory properties of roflumilast on bronchoalveolar granulocytes in endotoxin-induced airway inflammation in healthy subjects. (Word count: 240 words)

Neutrophil-mediated secondary tissue injury underlies acute respiratory distress syndrome (ARDS) and progression to multi-organ-failure (MOF) and death, processes linked to COVID-19-ARDS. This secondary tissue injury arises from dysregulated neutrophils and neutrophil extracellular traps (NETs) intended to kill pathogens, but instead cause cell-injury. Insufficiency of pleiotropic therapeutic approaches delineate the need for inhibitors of dysregulated neutrophil-subset(s) that induce subset-specific apoptosis critical for neutrophil function-shutdown. We hypothesized that neutrophils expressing the pro-survival dual endothelin-1/VEGF-signal peptide receptor, DEspR, are apoptosis-resistant like DEspR+ cancer-cells, hence comprise a consequential pathogenic neutrophil-subset in ARDS and COVID-19-ARDS. Here, we report the significant association of increased peripheral DEspR+CD11b+ neutrophil-counts with severity and mortality in ARDS and COVID-19-ARDS, and intravascular NET-formation, in contrast to DEspR[-] neutrophils. We detect DEspR+ neutrophils and monocytes in lung tissue patients in ARDS and COVID-19-ARDS, and increased neutrophil RNA-levels of DEspR ligands and modulators in COVID-19-ARDS scRNA-seq data-files. Unlike DEspR[-] neutrophils, DEspR+CD11b+ neutrophils exhibit delayed apoptosis, which is blocked by humanized anti-DEspR-IgG4S228P antibody, hu6g8, in ex vivo assays. Ex vivo live-cell imaging of Rhesus-derived DEspR+CD11b+ neutrophils showed hu6g8 target-engagement, internalization, and induction of apoptosis. Altogether, data identify DEspR+CD11b+ neutrophils as a targetable ‘rogue’ neutrophil-subset associated with severity and mortality in ARDS and COVID-19-ARDS.

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This HDM allergen particle generation is safe, specific and reproducible and can therefore be used for efficacy testing of immunotherapy and for basic clinical research.

Historically, the mortality of patients admitted to the ICU after allogeneic stem cell transplantation (alloSCT) is high. Advancements in transplantation procedures, infectious monitoring and supportive care may have improved the outcome. This study aimed to determine short-term and long-term mortality after ICU admission of patients after alloSCT and to identify prognostic clinical and transplantation-related determinants present at ICU admission for long-term outcome. A multicenter cohort study was performed to determine 30-day and 1-year mortality within 2 years following alloSCT. A total of 251 patients were included. The 30-day and 1-year mortality was 55% and 80%, respectively. Platelet count <25 × 10/L (OR: 2.26, CI: 1.02-5.01) and serum bilirubin >19 μmol/L (OR: 2.47 CI: 1.08-5.65) at admission, other donor than a HLA-matched-related or HLA-matched-unrelated donor (OR: 4.59, CI: 1.49-14.1) and vasoactive medication within 24 h (OR: 2.35, CI: 1.28-4.31) were associated with increased 30-day mortality. Other donor than a HLA-matched-related or HLA-matched-unrelated donor (OR: 1.9, CI: 1.13-3.19), serum bilirubin >77 (OR: 2.05, CI: 1.28-3.30) and vasoactive medication within 24 h (OR: 1.65, CI: 1.12-2.43) were associated with increased 1-year mortality. Neutropenia was associated with decreased 30-day and 1-year mortality (OR: 0.29, CI: 0.14-0.59 and OR: 0.70, CI: 0.48-0.98). Myeloablative conditioning and T cell-depleted transplantation were not associated with increased mortality.