A5025935170- Platelet Disorders and Treatments
- Extracellular vesicles in disease
- Systemic Lupus Erythematosus Research
- COVID-19 Clinical Research Studies
- Immune Response and Inflammation
- interferon and immune responses
- Inflammasome and immune disorders
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- T-cell and B-cell Immunology
- Cell Adhesion Molecules Research
- Blood disorders and treatments
- Monoclonal and Polyclonal Antibodies Research
- Dermatological and COVID-19 studies
- S100 Proteins and Annexins
- Blood groups and transfusion
- Psoriasis: Treatment and Pathogenesis
- Bone health and treatments
- Inflammatory Biomarkers in Disease Prognosis
- Complement system in diseases
- NF-κB Signaling Pathways
- Sphingolipid Metabolism and Signaling
- Myeloproliferative Neoplasms: Diagnosis and Treatment
- Genetic Syndromes and Imprinting
- Regulation of Appetite and Obesity
- Eicosanoids and Hypertension Pharmacology
Centre hospitalier universitaire de Québec
2013-2025
Université Laval
2016-2025
Centre hospitalier de l'Université Laval
2013-2023
Centre National de la Recherche Scientifique
2000-2005
Institut de Pharmacologie Moléculaire et Cellulaire
2000-2005
In addition to the overwhelming lung inflammation that prevails in COVID-19, hypercoagulation and thrombosis contribute lethality of subjects infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Platelets are chiefly implicated thrombosis. Moreover, they can interact viruses an important source inflammatory mediators. While a lower platelet count is associated severity mortality, little known about function during COVID-19.
Significance On activation, blood platelets package components from their cytoplasm into microparticles (MPs), tiny vesicles released by cytoplasmic membrane budding and shedding. Given that MPs can impact other cellular lineages on internalization, we aimed to decipher the mechanisms promoting MP internalization recipients. We modeled neutrophils identified a predominant lipid, 12(S)-hydroxyeicosatetranoic acid, as mediator critical for promotion of internalization. were found inside...
Significance Immune complexes (ICs) form when antibodies encounter their antigens. ICs are present in blood multiple pathological conditions. Given the abundance of platelets and that they express a receptor for ICs, called Fcγ IIA (FcγRIIA), we examined impact mouse model. We found circulating induced systemic shock, characterized by loss consciousness, activating platelet FcγRIIA. Shock was mediated liberation serotonin, molecule better known its role brain, from granules. During were...
Abstract During inflammation, steady-state hematopoiesis switches to emergency repopulate myeloid cells, with a bias toward the megakaryocytic lineage. Soluble inflammatory cues are thought be largely responsible for these alterations. However, how plasma factors rapidly alter bone marrow (BM) is not understood. Inflammation also drives platelet activation, causing release of platelet-derived extracellular vesicles (PEVs), which package diverse cargo and reprogram target cells. We...
The accumulation of DNA and nuclear components in blood their recognition by autoantibodies play a central role the pathophysiology systemic lupus erythematosus (SLE). Despite efforts, sources circulating autoantigens SLE are still unclear. Here, we show that SLE, platelets release mitochondrial DNA, majority which is associated with extracellular organelle. Mitochondrial patients correlates platelet degranulation. This process requires stimulation FcγRIIA, receptor for immune complexes....
Abstract Platelets are hyperactivated in coronavirus disease 2019 (COVID-19). However, the mechanisms promoting platelet activation by severe acute respiratory syndrome 2 (SARS-CoV-2) not well understood. This may be due to inherent challenges discriminating contribution of viral vs host components produced infected cells. is particularly true for enveloped viruses and extracellular vesicles (EVs), as they concomitantly released during infection share biophysical properties. To study this,...
Secreted phospholipase A2-IIA (sPLA2-IIA) hydrolyzes phospholipids to liberate lysophospholipids and fatty acids. Given its poor activity toward eukaryotic cell membranes, role in the generation of proinflammatory lipid mediators is unclear. Conversely, sPLA2-IIA efficiently bacterial membranes. Here, we show that affects immune system by acting on intestinal microbial flora. Using mice overexpressing transgene-driven human sPLA2-IIA, found microbiota was critical for both induction an...
BACKGROUND Whereas platelet transfusion is a common medical procedure, inflammation still occurs in fraction of transfused individuals despite the absence any apparent infectious agents. Platelets can shed membrane vesicles, called extracellular vesicles (EVs), some which contain mitochondria (mito+EV). With its content damage‐associated molecular pattern (DAMP), mitochondrion stimulate innate immune system. Mitochondrial DNA (mtDNA) recognized DAMP detected milieu numerous inflammatory...
Abstract Mitochondria are organelles that govern energy supply and control cell death. also express bacterial features, such as the presence of inner membrane cardiolipin a circular genome rich in hypomethylated CpG motifs. While mitochondrial extrusion by damaged organs or activated cells is thought to trigger innate immunity, it unclear whether extracellular mitochondria stimulate an adaptive immune response. We describe development novel assays detect autoantibodies specific two distinct...
COVID-19 is associated with robust inflammation and partially impaired antiviral responses. The modulation of inflammatory gene expression by SARS-CoV-2 not completely understood. In this study, we characterized the responses mounted during infection. K18-hACE2 mice were infected a Wuhan-like strain SARS-CoV-2, transcriptional translational interferons (IFNs), cytokines, chemokines analyzed in mouse lung homogenates. Our results show that infection induces several pro-inflammatory CC CXC...
Abstract Background Mitochondria play a critical role in the production of cell energy and regulation death. Therefore, mitochondria orchestrate numerous effector functions, including fine‐tuning immune system. While are mainly found intracellularly, they can escape confine during process extracellular vesicle release. Platelets patrol blood vessels to ensure vasculature integrity support In blood, platelets primary source circulating mitochondria. Activated produce vesicles, subset...
The mitochondrion supplies energy to the cell and regulates apoptosis. Unlike other mammalian organelles, mitochondria are formed by binary fission cannot be directly produced cell. They contain numerous copies of a compact circular genome that encodes RNA molecules proteins involved in mitochondrial oxidative phosphorylation. Whereas DNA (mtDNA) activates innate immune system if present cytosol or extracellular milieu, it is also target circulating autoantibodies systemic lupus...
Abstract Introduction Monosodium urate (MSU) microcrystals present in bone tissues of chronic gout can be ingested by nonprofessional phagocytes like osteoblasts (OBs) that express NLRP3 (nucleotide-binding domain and leucine-rich repeat region containing family receptor protein 3). MSU is known to activate inflammasomes professional phagocytes. We have identified a new role for coupled autophagy MSU-stimulated human OBs. Methods Normal OBs cultured vitro were investigated their capacity...
Objective: The lymphatic system is a circulatory that unidirectionally drains the interstitial tissue fluid back to blood circulation. Although lymph utilized by leukocytes for immune surveillance, it remains inaccessible platelets and erythrocytes. Activated cells release submicron extracellular vesicles (EV) transport molecules from donor cell. In rheumatoid arthritis, EV accumulate in joint where they can interact with numerous cellular lineages. However, whether exit inflamed recirculate...
ABSTRACT Rationale In addition to the overwhelming lung inflammation that prevails in COVID-19, hypercoagulation and thrombosis contribute lethality of subjects infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Platelets are chiefly implicated thrombosis. Moreover, they can interact viruses an important source inflammatory mediators. While a lower platelet count is associated severity mortality, little known about function during COVID-19. Objective To evaluate...
Coronavirus disease 19 (COVID-19) is the clinical manifestation of severe acute respiratory syndrome 2 (SARS-CoV-2) infection. A hallmark COVID-19 a lung inflammation characterized by an abundant leukocyte infiltrate, elevated levels cytokines/chemokines, lipid mediators (LMI) and microthrombotic events. Animal models are useful for understanding pathophysiological events leading to COVID-19. One such animal model K18-ACE2 transgenic mice. Despite their importance in inflammation, study LMI...
Mitochondria are organelles that exhibit several bacterial features, such as a double-stranded genome with hypomethylated CpG islands, formylated proteins, and cardiolipin-containing membranes. In systemic lupus erythematosus (SLE), mitochondria their inner components released into the extracellular space, potentially eliciting proinflammatory response from immune system. While cardiolipin mitochondrial DNA RNA confirmed targets of autoantibodies, other antigenic proteins in SLE remain to be...
Introduction: Despite timely recanalization, some ischemic stroke patients treated with endovascular thrombectomy experience persistent neurological deterioration. This has been partly attributed to no-reflow. Experimental models have indicated a critical role for platelets in this process. However, the mechanism and timing of platelet involvement remain unknown. Methods: Transient middle cerebral artery occlusion was performed C57Bl/6J mice. Intra-arterial blood sampled directly from brain...
Beta-cell (β-cell) injury is the hallmark of autoimmune diabetes. However, mechanisms by which autoreactive responses are generated in susceptible individuals not well understood. Extracellular vesicles (EV) produced mammalian cells under normal and stressed physiological states. They an important part cellular communication, may serve a role antigen processing presentation. We hypothesized that isolated human islets culture produce EV contain diabetes autoantigens (DAA) from these otherwise...
Platelets, known for maintaining blood balance, also participate in antimicrobial defense. Upon severeacute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, platelets become hyperactivated, releasing molecules such as cytokines, granule contents, and bioactive lipids. The key effector biolipids produced by include 12-hydroxyeicosatetraenoic acid (12-HETE) 12-hydroxyeicosatrienoic (12-HETrE), 12-lipoxygenase (12-LOX), prostaglandins thromboxane, cyclooxygenase-1. While prostaglandin...