Publications by authors named "Antoine Philippe Fournier"

Age is a major nonmodifiable risk factor for ischemic stroke. Central nervous system-associated macrophages (CAMs) are resident immune cells located along the brain vasculature at the interface between the blood circulation and the parenchyma. By using a clinically relevant thromboembolic stroke model in young and aged male mice and corresponding human tissue samples, we show that during aging, CAMs acquire a central role in orchestrating immune cell trafficking after stroke through the specific modulation of adhesion molecules by endothelial cells.

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Following a stroke, an inflammatory response occurs, characterized by an increased blood-brain barrier permeability, expression of endothelial trafficking molecules, and infiltration of immune cells. Adhesion molecules expressed on activated brain endothelial cells are potential biomarkers of intraparenchymal inflammation. However, in current clinical practice, it is not possible to measure endothelial activation using clinically available imaging.

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Article Synopsis
  • Multiple sclerosis (MS) is a complex disease involving immune cell infiltration into the central nervous system (CNS), but the exact mechanisms of this process are not well understood.
  • This study used single-cell RNA sequencing and analyses of endothelial cells in an animal model of MS to uncover gene expression patterns related to neuroinflammation, particularly focusing on venous endothelial cells (ECs).
  • Findings indicated that venous ECs play a significant role in neuroinflammation, with notable gene expression changes and molecular interactions identified, contributing to a better understanding of the processes that allow immune cells to enter the brain in MS.*
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Article Synopsis
  • - The study investigates the role of coxsackie and adenovirus receptor-like membrane protein (CLMP) in the migration of immune cells into the central nervous system (CNS) of patients with multiple sclerosis (MS), focusing on how it contributes to CNS damage.
  • - Researchers found that CLMP expression was significantly heightened in both the endothelial cells and immune cells of MS patients, particularly in active brain lesions, indicating its involvement in the inflammatory response associated with MS.
  • - Blocking CLMP with specific antibodies reduced immune cell migration across brain endothelial cells in laboratory tests, suggesting that targeting CLMP may offer a potential therapeutic approach for managing MS-related inflammation.
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Dysregulated immune profiles have been described in symptomatic patients infected with SARS-CoV-2. Whether the reported immune alterations are specific to SARS-CoV-2 infection or also triggered by other acute illnesses remains unclear. We performed flow cytometry analysis on fresh peripheral blood from a consecutive cohort of (a) patients hospitalized with acute SARS-CoV-2 infection, (b) patients of comparable age and sex hospitalized for another acute disease (SARS-CoV-2 negative), and (c) healthy controls.

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Background: Clinical observations support the hypothesis that stressful events increase relapse occurrence in multiple sclerosis patients, while stress-reduction strategies can modulate this effect. However, a direct cause-effect relationship between stress level and relapse cannot be firmly established from these data.

Objectives: The purpose of this work was to address whether modulation of stress could interfere with symptom relapse in an animal model of multiple sclerosis with relapsing-remitting course.

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New strategies for detecting disease activity in multiple sclerosis are being investigated to ameliorate diagnosis and follow-up of patients. Today, although magnetic resonance imaging (MRI) is widely used to diagnose and monitor multiple sclerosis, no imaging tools exist to predict the evolution of disease and the efficacy of therapeutic strategies. Here, we show that molecular MRI targeting the endothelial adhesion molecule P-selectin unmasks the pathological events that take place in the spinal cord of mice subjected to chronic or relapsing experimental autoimmune encephalomyelitis.

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