Project description:The aim of this study was to investigate microRNA expression pattern and its functional relevance on the commitment toward mucosal differentiation and on IgE-mediated activation of mast cells. To identify microRNA genes the expression of which change during the differentiation and activation of murine primary mast cells in vitro, the putative committed progenitors (c-kit+ cells isolated on day 6 from differentiating cultures), immature mast cells (BMMC), mucosal-type mast cells (MMC), and IgE-activated mast cells were compared by Agilent microRNA array. RNA was isolated by miRNeasy (Qiagen) from: 1) c-kit+ cells, isolated from differentiating cultures (in the presence of IL3 and SCF) derived from the bone marrow using MACS column purification, 2) immature BMMCs obtained by cultivation of bone marrow cells in the presence of IL3 and SCF for 4 weeks, 3) mucosal-type mast cells by additional differentiation of immature BMMCs for 5 days by supplementation of IL9 and TGFbeta, and 4) activated mast cells by presensitization with anti-DNP IgE followed by IgE-crosslinking by DNP-antigen challenge for 2 hours. Agilent microRNA microarray was run on these experimental groups. Four biological replicates were included in every experimental group.
Project description:This study investigated the antiallergic effects of Chamaecrista nomame extract (CN) and its isolated compound luteolin in a mouse model of ovalbumin (OVA)-induced asthma. We aimed to identify active substances within CN, elucidate their molecular signaling mechanisms, and assess their therapeutic potential for treating allergic asthma.
Project description:The aim of this study was to investigate microRNA expression pattern and its functional relevance on the commitment toward mucosal differentiation and on IgE-mediated activation of mast cells. To identify microRNA genes the expression of which change during the differentiation and activation of murine primary mast cells in vitro, the putative committed progenitors (c-kit+ cells isolated on day 6 from differentiating cultures), immature mast cells (BMMC), mucosal-type mast cells (MMC), and IgE-activated mast cells were compared by Agilent microRNA array.
Project description:Summary: Long-lived IgE plasma cells reside in the bone marrow of allergic mice and atopic humans, confer IgE serological memory and produce allergen-specific IgE that can drive anaphylaxis. Abstract: Immunoglobulin E (IgE) plays an important role in allergic diseases. Nevertheless, the source of IgE serological memory remains controversial. We re-examined the mechanism of serological memory in allergy using a dual-reporter system to track IgE plasma cells (PCs) in mice. Short-term allergen exposure resulted in the generation of IgE plasma cells that resided mainly in secondarylymphoid organs and produced IgE that was unable to degranulate mast cells. In contrast, chronic allergen exposure led to the generation of long-lived IgE plasma cells that were primarily derived from sequential class switching of IgG1, accumulated in the bone marrow (BM) and produced IgE capable of inducing anaphylaxis. Most importantly, IgE plasma cells were found in the BM of human allergic, but not non-allergic donors, and allergen-specific IgE produced by these cells was able to induce mast cell degranulation when transferred to mice. These data demonstrate that longlived IgE BMPCs arise during chronic allergen exposure and establish serological memory in both mice and humans.
Project description:TIM-3 is known to be expressed on dendritic cells, monocytes, melanoma cells, mast cells and on activated Th1 cells. In activated Th1 cells, stimulating TIM-3 by one of its ligands, galectin-9, leads to apoptosis and thus it plays a central role in terminating Th1-type immune responses. Interestingly, in IgE/antigen-activated mast cells TIM-3 enhances the production of IL-13 and IL-4. To get a more complete picture about the gene expression changes induced by TIM-3 in mast cells, in vitro differentiated mouse immature mast cells were stimulated by an agonist anti-TIM-3 antibody and IgE-sensitized mouse immature mast cells were activated by antigen and an agonist anti-TIM-3 antibody for 2 or 16 hours (overnight). Experiment Overall Design: Bone marrow cells were differentiated in RPMI + 10% FCS + 5 ng/ml mouse IL-3 + 40 ng/ml mouse SCF for >4 weeks. The purity of the cell cultures was >90% at this time point (FcERIa+/c-kit+ cells). These in vitro-differentiated immature mast cells were then treated by either control goat IgG or an agonist anti-mouse TIM-3 antibody (RnD Systems, 15 ug/ml for 2 or 16 hours). For the IgE/antigen-activated mouse mast cells, these in vitro-differentiated immature mast cells were sensitized by 5 ug/ml anti-DNP IgE (Sigma) for 1 hour and then treated with 100 ng/ml DNP-HSA (antigen, Sigma) and either control goat IgG or an agonist anti-mouse TIM-3 antibody (RnD Systems, 15 ug/ml) for 2 or 16 hours. The anti-TIM-3 samples were labeled by Cy5 and they were compared to the Cy3-labeled, goat IgG controls in a dual-color, paired experimental setup. The Agilent Whole Mouse Genome 4x44K expression microarray kit and Dual-Color Protocol version 5.5 were used in the experiments.
Project description:Mast cells are tissue resident granulocytes which are most abundant at the interface between tissues and the external environment, such as around blood vessels, in the skin or mucosal surfaces in the lungs and gut. Pathologically they are involved in allergic reactions and anaphylaxis, however they may also play protective roles in responses to some infections, particularly to pathogenic helminths. Mast cells also express high levels of the IL-33 receptor, which like TLRs, activates Myd88 dependent signalling pathways to drive de novo cytokine production in mast cells.IL-33 is a member of the IL-1 family known to stimulate a number of immune cell types including mast cells. IL-33 is a strong activator of de novo cytokine production in mast cells without inducing degranulation, although it has also been shown to synergise with other signals to promote degranulation. Bone Marrow-Derived Mast cells (BMMCs) were cultured as described previously [27]. Briefly, bone marrow was flushed in PBS and the cells pelleted by centrifugation. Cells were cultured at 1 million cells per ml in RPMI 1640 supplemented with 10% FBS (Biosera/Labtech), 5 mM l‐Glutamine (GIBCO Life Technologies), 100 U/ml Penicillin (GIBCO Life Technologies), 100 μg/ml Streptomycin (GIBCO Life Technologies), 25 mM HEPES (Lonza), 1 mM sodium pyruvate (Lonza), 1X nonessential amino acids (Lonza), 50 μM 2‐mercaptoethanol and 30 ng/ml IL‐3 (PeproTech). Cells were passaged twice per week and used between passage 12 and 16. 4 independent BMMC cultures were either stimulated with 10 ng/ml IL-33 for 48 hours or left unstimulated, followed by single shot LC-MS analysis.
Project description:Allergy is one of the least understood immunological response partly due to the diversity of allergens and the complexity of immune response against them. In allergic responses, mast cells are key players with their ability to rapidly degranulate and also generate de novo lipids and transcripts. Although the molecular details of degranulation in mast cell were studied in allergic inflammation, the transcriptional response involving chromatin remodeling, enhancer dynamics and long non-coding RNA (lncRNA) expression are largely unexplored. Here, using mouse bone marrow derived mast cells (BMMCs), we characterized the steady state, immunoglobulin E (IgE) and antigen (Ag) mediated epigenetic changes in mast cell chromatin and described the enhancer, super-enhancer and mRNA, lncRNA catalogue in these cells.
Project description:Allergy is one of the least understood immunological response partly due to the diversity of allergens and the complexity of immune response against them. In allergic responses, mast cells are key players with their ability to rapidly degranulate and also generate de novo lipids and transcripts. Although the molecular details of degranulation in mast cell were studied in allergic inflammation, the transcriptional response involving chromatin remodeling, enhancer dynamics and long non-coding RNA (lncRNA) expression are largely unexplored. Here, using mouse bone marrow derived mast cells (BMMCs), we characterized the steady state, immunoglobulin E (IgE) and antigen (Ag) mediated epigenetic changes in mast cell chromatin and described the enhancer, super-enhancer and mRNA, lncRNA catalogue in these cells.
Project description:Experimental IgE-mediated food allergy depends on intestinal anaphylaxis driven by interleukin (IL)-9. However, the primary cellular source of IL-9 and the mechanisms underlying the susceptibility to food-induced intestinal anaphylaxis remain unclear. Herein, we have reported the identification of multifunctional IL-9-producing mucosal mast cells (MMC9s) that can secrete prodigious amounts of IL-9 and IL-13 in response to IL-33, and mast cell protease-1 (MCPt-1) in response to antigen and IgE complex crosslinking, respectively. Repeated intragastric antigen challenge induced MMC9 development that required T cells, IL-4, and STAT6 transcription factor, but not IL-9 signals. Mice ablated of MMC9 induction failed to develop intestinal mastocytosis, which resulted in decreased food allergy symptoms that could be restored by adoptively transferred MMC9s. Finally, atopic patients that developed food allergy displayed increased intestinal expression of Il9 and MC-specific transcripts. Thus, the induction of MMC9s is a pivotal step to acquire the susceptibility to IgE-mediated food allergy. dUTP mRNA-Seq profiles of indicated hematopoietic cell lineages were generated on Illumina HiSeq2500. Hematopoietic cells were isolated from Balb/C mice that developed food allergy and bone marrow-derived mast cells were generated from naïve Balb/C mice
Project description:We performed large-scale comparative microarrays of bone marrow -derived mast cells and basophils at rest, upon an adaptive-type action (IgE-crosslinking) or upon innate-type activation (IL-33-activation).