Project description:Anti-neutrophil cytoplasmic autoantibodies (ANCAs) are directed against lysosomal components of neutrophils. ANCAs directed to proteinase 3 and myeloperoxidase (MPO) in particular are associated with distinct forms of small vessel vasculitides. MPO is an abundant neutrophil-derived heme protein that is part of the antimicrobial defense system. The protein is typically present in the azurophilic granules of neutrophils, but a large portion may also enter the extracellular space. It remains unclear why MPO is frequently the target of antibody-mediated autoimmune responses. MPO is a homodimeric glycoprotein, posttranslationally modified with complex sugars at specific sites. Glycosylation can strongly influence protein function, affecting its folding, receptor interaction, and backbone accessibility. MPO potentially can be heavily modified as it harbors 5 putative N-glycosylation sites (10 in the mature dimer). Although considered important for MPO structure and function, the full scope and relative abundance of the glycans attached to MPO is unknown. Here, combining bottom-up glycoproteomics and native MS approaches, we structurally characterized MPO from neutrophils of healthy human donors. We quantified the relative occupancy levels of the glycans at each of the five sites and observed complex heterogeneity and site-specific glycosylation. In particular, we detected glycosylation phenotypes uncommon for glycoproteins in the extracellular space, such as a high abundance of phosphorylated high-mannose species and severely truncated small glycans having the size of paucimannose or smaller. We hypothesize that the atypical glycosylation pattern found on MPO might contribute to its specific processing and presentation as a self-antigen by antigen-presenting cells.
Project description:Elevated NLR (neutrophil-lymphocyte ratio) in elective vascular surgery (EVS) patients is associated with increased mortality independent of perioperative surgical outcome. To understand why high NLR is associated with higher mortality, we investigated neutrophil and lymphocyte transcriptome expression in patients undergoing EVS.
Project description:The human plasma glycoproteome holds enormous potential to identify personalized biomarkers to diagnose and understand disease. Recent advances in mass spectrometry and software development are opening novel avenues to mine the glycoproteome for protein- and site-specific glycosylation changes. Here, we describe a novel plasma N-glycoproteomics method for disease diagnosis and evaluated its clinical applicability by performing comparative glycoproteomics in blood plasma of 40 controls and a cohort of 74 patients with 13 different genetic diseases that directly impact the protein N-glycosylation pathway. The plasma glycoproteome yielded high-specificity biomarker signatures for each of the individual genetic defects. Bioinformatic analyses revealed site-specific glycosylation differences that could be explained by underlying glycobiology and in specific diseases by protein-intrinsic factors. Our work illustrates the strong potential of plasma glycoproteomics to significantly increase specificity of glycoprotein biomarkers with direct insights in site-specific glycosylation changes to better understand the mechanisms underlying human disease.
Project description:Interventions: monocyte/neutrophil apheresis
non monocyte/neutrophil apheresis
Primary outcome(s): Evaluation neutrophil function of patients at high risk for postoperative infection treated with monocyte/neutrophil apheresis
Study Design: Parallel Non-randomized
Project description:Interventions: multiple monocyte/neutrophil apheresis
non monocyte/neutrophil apheresis
Primary outcome(s): Evaluation neutrophil function of patients at high risk for postoperative infection treated with monocyte/neutrophil apheresis
Study Design: Parallel Non-randomized
Project description:During pneumonic plague, the bacterium Yersinia pestis elicits the development of inflammatory lung lesions that continue to expand throughout infection. This lesion development and persistence is poorly understood. Here, we examine spatially distinct regions of lung lesions using laser capture microdissection and RNAseq analysis to identify transcriptional differences between lesion microenvironments. We show that cellular pathways involved in leukocyte migration and apoptosis are down regulated in the center of lung lesions compared to the periphery. Probing for the bacterial factor(s) important for the alteration in neutrophil survival, we show both in vitro and in vivo that Y. pestis increases neutrophil survival in a manner that is dependent on the type-III secretion system effector YopM. This research explores the complexity of spatially distinct host - microbe interactions and emphasizes the importance of cell relevance in assays in order to fully understand Y. pestis virulence. We examine spatially distinct regions of lung lesions using laser capture microdissection and RNAseq analysis to identify transcriptional differences between lesion microenvironments. Sample types: uninfected BM-PMN, infected BM-PMN, lesion periphery, lesion center.
Project description:We report cytokine specific changes in gene expression in the human neutrophil transcriptome using TNF-alpha and GM-CSF stimulation of healthy neutrophils Healthy human neutrophils were stimulated with TNF-alpha or GM-CSF for 1h in vitro. RNA was analysed by SOLiD and Illumina sequencing. RNA from one biological donor was sequenced on both platforms, and two different biological donors were sequenced by Illumina.
Project description:This SuperSeries is composed of the following subset Series: GSE32542: Murine serum reactivity to common autoantigens in response to immunization with neutrophil extracellular traps GSE32543: Human and murine serum reactivity to specific histone posttranslational modifications in neutrophil extracellular traps Refer to individual Series
Project description:Acute respiratory distress syndrome (ARDS) is a severe critical condition with a high mortality that is currently in focus given that it is associated with mortality caused by coronavirus induced disease 2019 (COVID-19). Neutrophils play a key role in the lung injury characteristic of non-COVID-19 ARDS and there is also accumulating evidence of neutrophil mediated lung injury in patients who succumb to infection with SARS-CoV-2. We undertook a functional proteomic and metabolomic survey of circulating neutrophil populations, comparing patients with COVID-19 ARDS and non-COVID-19 ARDS to understand the molecular basis of neutrophil dysregulation. Expansion of the circulating neutrophil compartment and the presence of activated low and normal density mature and immature neutrophil populations occurs in ARDS, irrespective of cause. Release of neutrophil granule proteins, neutrophil activation of the clotting cascade and upregulation of the Mac-1 platelet binding complex with formation of neutrophil platelet aggregates is exaggerated in COVID-19 ARDS. Importantly, activation of components of the neutrophil type I interferon responses is seen in ARDS following infection with SARS-CoV-2, with associated rewiring of neutrophil metabolism to promote glutamine utilisation, and the upregulation of antigen processing and presentation. Whilst dexamethasone treatment constricts the immature low density neutrophil population it does not impact upon prothrombotic hyperinflammatory neutrophil signatures.
Project description:Metastasis is considered to be responsible for 90% of cancer-related deaths. Although it is clinically evident that metastatic patterns vary by primary tumor type, the molecular mechanisms underlying the site-specific nature of metastasis are an area of active investigation. One mechanism that has emerged as an important player in this process is glycosylation, or the addition of sugar moieties onto protein and lipid substrates. Glycosylation is the most common post-translational modification, occurring on more than 50% of translated proteins. Many of those proteins are either secreted or expressed on the cell membrane, thereby making glycosylation an important mediator of cell-cell interactions, including tumor-microenvironment interactions. It has been recently discovered that alteration of glycosylation patterns influences cancer metastasis, both globally and in a site-specific manner. This review will summarize the current knowledge regarding the role of glycosylation in the tropism of cancer cells for several common metastatic sites, including the bone, lung, brain, and lymph nodes.