Project description:We found that neutrophils were homing back to bone marrow and induced myelopoiesis after AVP treatment.This study investigated how neutrophils promoted HSC differentiation by comparing the expression of genes between control and AVP treatment neutrophils.We demonstrated that AVP treatment increased the expression of a variety of cytokine genes, especially IL36G, and the augmentation of bone marrow myelopoiesis involves IL36G-IL1RL2 axis.
Project description:Although the accumulation of neutrophils in the lungs and airways is common to many inflammatory lung diseases, including acute lung injury, the alterations that neutrophils undergo as they leave the peripheral circulation and migrate into the lungs have not been well characterized. Human volunteers were exposed to endotoxin by bronchoscopic instillation. The resulting air space neutrophil accumulation and peripheral blood neutrophils were isolated 16 h later, compared with circulating neutrophils isolated before or after to the pulmonary endotoxin exposure, and compared with circulating neutrophils exposed to endotoxin in vitro. Microarray analysis was performed on air space, circulatory, and in vitro endotoxin-stimulated neutrophils. Functional analysis included the determination of neutrophil apoptosis, chemotaxis, release of cytokines and growth factors, and superoxide anion release. Dramatic gene expression differences were apparent between air space and circulating neutrophils: approximately 15% of expressed genes have altered expression levels, including broad increases in inflammatory- and chemotaxis-related genes, as well as antiapoptotic and IKK-activating pathways. Functional analysis of air space compared with circulating neutrophils showed increased superoxide release, diminished apoptosis, decreased IL-8-induced chemotaxis, and a pattern of IL-8, macrophage inflammatory protein-1beta, monocyte chemoattractant protein-1, and tumor necrosis factor-alpha release different from either unstimulated or LPS-stimulated circulating neutrophils. Many of these changes are not elicited by in vitro treatment with endotoxin. Limited differences were detected between circulating neutrophils isolated before and 16 h after pulmonary endotoxin instillation. These results suggest that neutrophils sequestered in the lung become fundamentally different from those resident in the circulation, and this difference is distinct from in vitro activation with endotoxin.
Project description:We report the high-throughput sequencing results in mammalian cell lines. Neutrophils were induced by HL-60 with 1umol/L ATRA(all-trans retinoid acid ) stimulation for 7days. Neutrophils were then stimulated with 0.05ug/mL AGEs,30mmol/L D-glucose, AGEs+D-glucose and 0.05ug/mL BSA (control) for 24-hours, then mRNA profiles were extracted and tested using Illumina Hiseq 4000. This study provides a prospective work for the influence of AGEs and high-glucose in human neutrophils.
Project description:Neutrophil gene transcription following lipopolysaccharide exposure. Microarray analysis of lipopolysaccharide-treated human neutrophils. Neutrophils respond to infection by degranulation, release of reactive oxygen intermediates, and secretion of chemokines and cytokines; however, activation of neutrophil transcriptional machinery has been little appreciated. Recent findings suggest that gene expression may represent an additional neutrophil function after exposure to lipopolysaccharide (LPS). We performed microarray gene expression analysis of 4,608 mostly nonredundant genes on LPS-stimulated human neutrophils. Analysis of three donors indicated some variability but also a high degree of reproducibility in gene expression. Twenty-eight verifiable, distinct genes were induced by 4 h of LPS treatment, and 13 genes were repressed. Genes other than cytokines and chemokines are regulated; interestingly, genes involved in cell growth regulation and survival, transcriptional regulation, and interferon response are among those induced, whereas genes involved in cytoskeletal regulation are predominantly repressed. In addition, we identified monocyte chemoattractant protein-1 as a novel LPS-regulated chemokine in neutrophils. Included in these lists are five clones with no defined function. These data suggest molecular mechanisms by which neutrophils respond to infection and indicate that the transcriptional potential of neutrophils is greater than previously thought.
Project description:S100A8/A9 is a proinflammatory mediator released by myeloid cells during many acute and chronic inflammatory disorders. However, the precise mechanism of its release from the cytosolic compartment of neutrophils is still elusive. We report here that E-selectin-induced rapid S100A8/A9 release during inflammation occurs in a NLRP3 inflammasome-dependent fashion. Mechanistically, E-selectin engagement triggers Bruton?s tyrosine kinase dependent tyrosine phosphorylation of NLRP3. Concomitant potassium efflux via the voltage-gated potassium channel KV1.3 mediates ASC oligomerization. This is followed by caspase-1 cleavage and downstream activation of pore forming gasdermin D, enabling cytosolic S100A8/A9 to be released. Strikingly, E-selectin-mediated gasdermin D pore formation does not result in cell death, but is a transient process involving activation of the ESCRT-III membrane repair machinery. These findings do not only elucidate the molecular mechanisms of controlled S100A8/A9 release but also identify the NLRP3/gasdermin D axis as a rapid and reversible activation system in neutrophils during inflammation.
Project description:Lipocalin 24p3 (24p3) is a neutrophil secondary granule protein. 24p3 is also a siderocalin, which binds several bacterial siderophores. It was therefore proposed that synthesis and secretion of 24p3 by stimulated macrophages or release of 24p3 upon neutrophil degranulation sequesters iron-laden siderophores to attenuate bacterial growth. Accordingly, 24p3-deficient mice are susceptible to bacterial pathogens whose siderophores would normally be chelated by 24p3. Specific granule deficiency (SGD) is a rare congenital disorder characterized by complete absence of proteins in secondary granules. Neutrophils from SGD patients, who are prone to bacterial infections, lack normal functions but the potential role of 24p3 in neutrophil dysfunction in SGD is not known. Here we show that neutrophils from 24p3-deficient mice are defective in many neutrophil functions. Specifically, neutrophils in 24p3-deficient mice do not extravasate to sites of infection and are defective for chemotaxis. A transcriptome analysis revealed that genes that control cytoskeletal reorganization are selectively suppressed in 24p3-deficient neutrophils. Additionally, small regulatory RNAs (miRNAs) that control upstream regulators of cytoskeletal proteins are also increased in 24p3-deficient neutrophils. Further, 24p3-deficient neutrophils failed to phagocytose bacteria, which may account for the enhanced sensitivity of 24p3-deficient mice to both intracellular (Listeria monocytogenes) and extracellular (Candida albicans, Staphylococcus aureus) pathogens. Interestingly, Listeria does not secrete siderophores and additionally, the siderophore secreted by Candida is not sequestered by 24p3. Therefore, the heightened sensitivity of 24p3-deficient mice to these pathogens is not due to sequestration of siderophores limiting iron availability, but is a consequence of impaired neutrophil function. Key words: Lipocalin, 24p3, neutrophils, cell motility, chemotaxis, MIRNA-362-3p To address the role of lipocalin 2 in unstimulated and fMLP-stimulated neutrophils derived from mouse bone marrow, we performed micorarray analysis of gene expression in unstimulated wild type (N=3), unstimulated lcn2 knockout (N=3), fMLP-stimulated wild type (N=2) and fMLP-stimulated lcn2 knockout (N=2) neutrophils. Upon stimulation, neutrophils were treated by fMLP at 10 micromolar for 20 minutes at 37 centigrade.
Project description:Neutrophils form the most abundant leukocyte subset and are central to many disease processes. Technical challenges in transcriptomic profiling have prohibited genetical genomic approaches to date. Here, we map expression quantitative trait loci (eQTL) in peripheral blood CD16+ neutrophils from 101 healthy European adults. This dataset includes expression data from neutrophils. The genotypes and expression data from monocytes can be found in E-MTAB-2232 - Genetics of gene expression across innate immune stimulation in primary monocytes.
Project description:Degranulating mast cells (MCs) release inflammatory mediators (proteins, lipids, small molecules), including chemokines and chemoattractants, which recruit other immune cells in tissues. Neutrophils can initiate self-amplifying swarming responses via intercellular communication through the lipid leukotriene B4 (LTB4). Initially discovered by two-photon intravital microscopy in mice and confocal live cell imaging, we show that degranulating MCs release LTB4 and exploit this attractant by re-directing neutrophils to MCs. In a process generally termed entosis, neutrophil cluster formation around MCs results in the trapping of living neutrophils inside MC vacuoles in vivo and in vitro. Thus, we identify a novel cell-in-cell structure between MCs and neutrophils, which we term “Mast Cell Intracellular Trap” (MIT). Compared to MCs, MITs revealed improved MC metabolism and recovery after degranulation. This leads to several benefits for MITs: (1) they can be more efficiently re-stimulated than MCs, (2) they show improved survival under nutrient limitation, and (3) MITs store neutrophil proteins, DNA and effector molecules, which can be released after re-stimulation. In this context, we compare the secretome (secreted proteins) of MCs and MITs (in cell culture) before and subsequent to degranulation via label-free nanoLC-MS. In summary, mast cells trap and cannibalize swarming neutrophils, which supply nutrients, proteins and inflammatory molecules to recovering MCs. Our studies may have potential implications for chronically activated MCs in MC-related immune disorders.