Project description:Fatal COVID-19 is often complicated by hypoxemic respiratory failure and acute respiratory distress syndrome (ARDS). Mechanisms governing lung injury and repair in ARDS remain poorly understood because there are no biomarker-targeted therapeutics for patients with ARDS. We hypothesized that plasma proteomics may uncover unique biomarkers that correlate with disease severity in COVID-19 ARDS. We analyzed the circulating plasma proteome from 32 patients with ARDS and COVID-19 using an aptamer-based platform, which measures 7289 proteins, and correlated protein measurements with sequential organ failure assessment (SOFA) scores at 2 time points (Days 1 and 7 following ICU admission). We compared differential protein abundance and SOFA scores at each individual time point and identified 119 proteins at Day 1 and 46 proteins at Day 7 that correlated with patient SOFA scores. We modeled the relationship between dynamic protein abundance and changes in SOFA score between Days 1 and 7 and identified 39 proteins that significantly correlated with changes in SOFA score. Using Ingenuity Pathway Analysis, we identified increased ephrin signaling and acute phase response signaling correlated with increased SOFA scores over time, while pathways related to pulmonary fibrosis signaling and wound healing had an inverse relationship with SOFA scores between Days 1 and 7. These findings suggest that persistent inflammation may drive worsened disease severity, while repair processes correlate with improvements in organ dysfunction over time. This approach is generalizable to more diverse ARDS cohorts for identification of protein biomarkers and disease mechanisms as we strive towards targeted therapies in ARDS.
Project description:SARS-CoV-2 is a novel coronavirus that causes acute respiratory distress syndrome (ARDS), death and long-term sequelae. Innate immune cells are critical for host defense but are also the primary drivers of ARDS. The relationships between innate cellular responses in ARDS resulting from COVID-19 compared to other causes of ARDS, such as bacterial sepsis is unclear. Moreover, the beneficial effects of dexamethasone therapy during severe COVID-19 remain speculative, but understanding the mechanistic effects could improve evidence-based therapeutic interventions. To interrogate these relationships, we developed an scRNAseq atlas that is freely accessible (biernaskielab.ca/COVID_neutrophil). We discovered that compared to bacterial ARDS, COVID-19 was associated with distinct neutrophil polarization characterized by either interferon (IFN) or prostaglandin (PG) active states. Neutrophils from bacterial ARDS had higher expression of antibacterial molecules such as PLAC8 and CD83. Dexamethasone therapy in COVID patients rapidly altered the IFNactive state, downregulated interferon responsive genes, and activated IL1R2+ve neutrophils. Dexamethasone also induced the emergence of immature neutrophils expressing immunosuppressive molecules ARG1 and ANXA1, which were not present in healthy controls. Moreover, dexamethasone remodeled global cellular interactions by changing neutrophils from information receivers into information providers. Importantly, male patients had higher proportions of IFNactive neutrophils and a greater degree of steroid-induced immature neutrophil expansion. Indeed, the highest proportion of IFNactive neutrophils was associated with mortality. These results define neutrophil states unique to COVID-19 when contextualized to other life-threatening infections, thereby enhancing the relevance of our findings at the bedside. Furthermore, the molecular benefits of dexamethasone therapy are also defined. The identified molecular pathways can now be targeted to develop improved therapeutics.
Project description:Acute Respiratory Distress Syndrome (ARDS) remains a significant clinical challenge, with its pathogenesis not fully understood. Proteomic analyses of plasma and bronchoalveolar lavage fluid (BALF) in patients with ARDS have been performed to uncover diagnostic and prognostic markers, although previous studies have not adequately focused on longitudinal biomarker comparison. This study aims to elucidate the proteomic profiles of patients with ARDS in acute and subacute phases to better understand pathophysiological progression of ARDS.
Project description:Background: COVID-19 has infected more than 100-million worldwide. Children appear less susceptible to COVID-19 and present with milder symptoms. Cases of children with COVID-19 developing clinical features of Kawasaki-disease have been described. Methods: We utilised SWATH-MS proteomics to determine the plasma proteins expressed in healthy children, children with multisystem inflammatory syndrome (MIS-C) and children with COVID-19 induced ARDS. Pathway analyses were performed to determine the affected pathways. Results: 76 proteins were differentially expressed across the groups, with 85 and 52 proteins specific to MIS-C and COVID-19 ARDS. Complement and coagulation activation were implicated in these clinical phenotypes, however there was contribution of FcGR and BCR activation in MIS-C and scavenging of heme and retinoid metabolism in COVID-19 ARDS. Conclusions: We show proteome differences in MIS-C and COVID-ARDS, although both show complement and coagulation dysregulation. The results may be helpful in developing therapeutic targets that could improve the outcomes for these children.
Project description:We compared differential gene expression in tracheal aspirates collected mechanically ventilated subjects with COVID-19 ARDS to gene expression in tracheal aspirates from: 1) subjects with ARDS from other casues and 2) mechanically ventilated controls without evidence of pulmonary disease.
Project description:Despite a significant progress in the treatment of Acute Respiratory Distress Syndrome (ARDS), our ability to identify early patients and predict outcome remains limited. In this study, we aimed to characterize small RNA content of plasma exosomes from ARDS patients in order to identify potential diagnostic biomarkers of the disease. For the first time, we profiled miRNA expression levels in plasma-derived exosomes from ARDS patients (n=8) compared to healthy subjects (n=10) by small RNA-seq. It allowed us to identify 12 exosomal miRNAs differentially expressed in ARDS context (padj<0.05).
Project description:Acute respiratory distress syndrome (ARDS) is a respiratory failure in critically ill patients, and the molecular mechanisms underlying its pathogenesis and severity are poorly understood. We evaluated mRNA and miRNA in patients with ARDS and elucidated the pathogenesis of ARDS, following mRNA and miRNA integration analysis. Thirty-four ARDS patients were compared with 15 healthy donors. 1233 mRNAs and 6 miRNAs were upregulated and 1580 mRNAs and 13 miRNAs were downregulated in ARDS patients compared healthy donors. In both mRNA and miRNA-targeted mRNA, the canonical pathway analysis showed that PD-1 and PD-L1 cancer immunotherapy pathway was most activated and Th2 pathway was most suppressed. miR-149-3p and several miRNAs were identified as upstream regulators. Integrated analysis of mRNAs and miRNAs showed that T cells were dysfunctional in ARDS patients.
Project description:Acute respiratory distress syndrome (ARDS) is a respiratory failure in critically ill patients, and the molecular mechanisms underlying its pathogenesis and severity are poorly understood. We evaluated mRNA and miRNA in patients with ARDS and elucidated the pathogenesis of ARDS, following mRNA and miRNA integration analysis. Thirty-four ARDS patients were compared with 15 healthy donors. 1233 mRNAs and 6 miRNAs were upregulated and 1580 mRNAs and 13 miRNAs were downregulated in ARDS patients compared healthy donors. In both mRNA and miRNA-targeted mRNA, the canonical pathway analysis showed that PD-1 and PD-L1 cancer immunotherapy pathway was most activated and Th2 pathway was most suppressed. miR-149-3p and several miRNAs were identified as upstream regulators. Integrated analysis of mRNAs and miRNAs showed that T cells were dysfunctional in ARDS patients.
Project description:While critical for host defense, innate immune cells are also pathologic drivers of acute respiratory distress syndrome (ARDS). Innate immune dynamics during COVID-19 ARDS, compared to ARDS from other respiratory pathogens, is unclear. Moreover, mechanisms underlying beneficial effects of dexamethasone during severe COVID-19 remain elusive. Using scRNA-seq and plasma proteomics, we discovered that compared to bacterial ARDS, COVID-19 was associated with expansion of distinct neutrophil states characterized by interferon (IFN) and prostaglandin (PG) signalling. Dexamethasone during severe COVID-19 depleted circulating neutrophils, altered IFNactive neutrophils, downregulated interferon-stimulated gene, and activated IL1R2+ve neutrophils. Dexamethasone also expanded immunosuppressive immature neutrophils and remodeled cellular interactions by changing neutrophils from information receivers into information providers. Male patients had higher proportions of IFNactive neutrophils, preferential steroid-induced immature neutrophil expansion, and possibly different effects on outcome. Our single-cell atlas (www.biernaskielab.ca/COVID_neutrophil) defines COVID-19-enriched neutrophil states and molecular mechanisms of dexamethasone action to develop targeted immunotherapies for severe COVID-19.