Publications by authors named "Pierre Van Mol"

Background: COVID-19-associated pulmonary aspergillosis (CAPA) is a severe superinfection with the fungus Aspergillus affecting patients who are critically ill with COVID-19. The pathophysiology and the role of neutrophil extracellular traps (NETs) in this infection are largely unknown. We aimed to characterise the immune profile, with a focus on neutrophils and NET concentrations, of critically ill patients with COVID-19, with or without CAPA.

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Immune checkpoints (ICs) play a central role in maintaining immune homoeostasis. The discovery that tumours use this physiological mechanism to avoid elimination by the immune system, opened up avenues for therapeutic targeting of ICs as a novel way of treating cancer. However, this therapy a new array of autoimmune side effects, termed immune-related adverse events (irAEs).

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The human chemokine stromal cell-derived factor-1 (SDF-1) or CXCL12 is involved in several homeostatic processes and pathologies through interaction with its cognate G protein-coupled receptor CXCR4. Recent research has shown that CXCL12 is present in the lungs and circulation of patients with coronavirus disease 2019 (COVID-19). However, the question whether the detected CXCL12 is bioactive was not addressed.

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Patients with severe COVID-19 develop acute respiratory distress syndrome (ARDS) that may progress to cytokine storm syndrome, organ dysfunction, and death. Considering that complement component 5a (C5a), through its cellular receptor C5aR1, has potent proinflammatory actions and plays immunopathological roles in inflammatory diseases, we investigated whether the C5a/C5aR1 pathway could be involved in COVID-19 pathophysiology. C5a/C5aR1 signaling increased locally in the lung, especially in neutrophils of critically ill patients with COVID-19 compared with patients with influenza infection, as well as in the lung tissue of K18-hACE2 Tg mice (Tg mice) infected with SARS-CoV-2.

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Article Synopsis
  • This study investigates the role and behavior of natural killer (NK) cells in COVID-19 patients, using techniques like flow cytometry and single-cell RNA sequencing, to understand how these immune cells respond during different stages and severity of the disease.* -
  • Results show that NK cells from different patient groups (like those in low-care vs. ICU) exhibit distinct activated phenotypes, with early-stage patients showing higher levels of cytotoxic molecules, while later-stage patients display increased levels of specific cytokines (IFN-γ, TNF-α) without typical stimulation.* -
  • Key findings also reveal that, although NK cells in severe patients had lower cytotoxic molecules, they still managed to kill target cells effectively, while
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Background: Immune checkpoint inhibitor (ICI)-related pneumonitis is the most frequent fatal immune-related adverse event associated with programmed cell death protein-1/programmed death ligand-1 blockade. The pathophysiology however remains largely unknown, owing to limited and contradictory findings in existing literature pointing at either T-helper 1 or T-helper 17-mediated autoimmunity. In this study, we aimed to gain novel insights into the mechanisms of ICI-related pneumonitis, thereby identifying potential therapeutic targets.

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Aims: Severe acute respiratory syndrome coronavirus-2 infection causes COVID-19, which in severe cases evokes life-threatening acute respiratory distress syndrome (ARDS). Transcriptome signatures and the functional relevance of non-vascular cell types (e.g.

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Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to the angiotensin-converting enzyme 2 (ACE2) receptor, a critical component of the kallikrein-kinin system. Its dysregulation may lead to increased vascular permeability and release of inflammatory chemokines. Interactions between the kallikrein-kinin and the coagulation system might further contribute to thromboembolic complications in COVID-19.

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We conducted a prospective single-center observational study to determine lung ultrasound reliability in assessing global lung aeration in 38 hospitalized patients with non-critical COVID-19. On admission, fixed chest CT scans using visual (CTv) and software-based (CTs) analyses along with lung ultrasound imaging protocols and scoring systems were applied. The primary endpoint was the correlation between global chest CTs score and global lung ultrasound score.

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Understanding the pathology of COVID-19 is a global research priority. Early evidence suggests that the respiratory microbiome may be playing a role in disease progression, yet current studies report contradictory results. Here, we examine potential confounders in COVID-19 respiratory microbiome studies by analyzing the upper (n = 58) and lower (n = 35) respiratory tract microbiome in well-phenotyped COVID-19 patients and controls combining microbiome sequencing, viral load determination, and immunoprofiling.

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Objectives: Emerging evidence of dysregulation of the myeloid cell compartment urges investigations on neutrophil characteristics in coronavirus disease 2019 (COVID-19). We isolated neutrophils from the blood of COVID-19 patients receiving general ward care and from patients hospitalised at intensive care units (ICUs) to explore the kinetics of circulating neutrophils and factors important for neutrophil migration and activation.

Methods: Multicolour flow cytometry was exploited for the analysis of neutrophil differentiation and activation markers.

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How the innate and adaptive host immune system miscommunicate to worsen COVID-19 immunopathology has not been fully elucidated. Here, we perform single-cell deep-immune profiling of bronchoalveolar lavage (BAL) samples from 5 patients with mild and 26 with critical COVID-19 in comparison to BALs from non-COVID-19 pneumonia and normal lung. We use pseudotime inference to build T-cell and monocyte-to-macrophage trajectories and model gene expression changes along them.

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Objectives: The pandemic spread of the coronavirus SARS-CoV-2 is due, in part, to the immunological properties of the host-virus interaction. The clinical presentation varies from individual to individual, with asymptomatic carriers, mild-to-moderate-presenting patients and severely affected patients. Variation in immune response to SARS-CoV-2 may underlie this clinical variation.

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: Activation of the MET pathway through amplifications or mutations is present in 3-4% of stage IV non-squamous non-small cell lung cancers (NSCLC). High amplifications and exon 14 skipping mutations are associated with poor prognosis: new treatments are needed for these patients. Capmatinib is a highly selective, potent small-molecule MET inhibitor with antitumor activity in NSCLC and .

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