Project description:To deeply investigate the details of the nano-SiO2 effects, we examined the gene expression profile alterations after nano-SiO2 treatment in BMMCs. The difference analysis between the groups showed that 285 genes were significantly expressed after treatment with nano-SiO2. Compared with the blank group, both nano-SiO2 exposure and DNP-HSA stimulation increased the expression of genes related to the MAPK signaling pathway in mast cells to varying degrees.
Project description:To screen for novel toxicological endpoints of nano-particles, we conducted an in vitro expression profiling study using human lung epithelial cells (A549). To identify effects that are specific to size or chemical origin, we compared gene expression of A549 cells treated with nano-sized and micro-sized particulates of two chemical origins (carbon and silica) to the control (untreated) cells.
Project description:Using a macrophage cell line, we demonstrate the ability of amorphous silica particles to stimulate inflammatory protein secretion and induce cytotoxicity. Whole genome microarray analysis of early gene expression changes induced by 10nm and 500nm particles showed that the magnitude of change for the majority of genes correlated more tightly with particle surface area than either particle mass or number. Gene expression changes that were size-specific were also identified, however the overall biological processes represented by all gene expression changes were nearly identical, irrespective of particle diameter. Our results suggest that on an equivalent nominal surface area basis, common biological modes of action are expected for nano- and supranano-sized silica particles. Keywords: Dose-response study
Project description:In contrast to their clearly defined roles in allergic diseases, the physiologic functions of Immunoglobulin E antibodies (IgEs) and mast cells (MCs) remain enigmatic. Recent research supports the toxin hypothesis, showing that MCs and IgE-related type 2 immune responses can enhance host defense against certain noxious substances, including honeybee venom (BV). However, the mechanisms by which MCs can interfere with BV toxicity are unknown. In this study, we assessed the role of IgE and certain MC products in MC-mediated BV detoxification. We applied in vitro and in vivo fluorescence microscopy imaging, and flow cytometry, fibroblast-based toxicity assays and mass spectrometry to investigate IgE-mediated detoxification of BV cytotoxicity by mouse and human MCs in vitro. Pharmacologic strategies to interfere with MC-derived heparin and proteases helped to define the importance of specific detoxification mechanisms. Venom-specific IgE increased the degranulation and cytokine responses of MCs to BV in vitro. Passive serum sensitization enhanced MC degranulation in vivo. IgE-activated mouse or human MCs exhibited enhanced potential for detoxifying BV by both proteolytic degradation and heparin-related interference with toxicity. Mediators released by IgE-activated human MCs efficiently degraded multiple BV toxins. Our results both reveal that IgE sensitization enhances the MC’s ability to detoxify BV and also assign efficient toxin-neutralizing activity to MC-derived heparin and proteases. Our study thus highlights the potential importance of IgE, MCs, and particular MC products in defense against BV.
Project description:Using a macrophage cell line, we demonstrate the ability of amorphous silica particles to stimulate inflammatory protein secretion and induce cytotoxicity. Whole genome microarray analysis of early gene expression changes induced by 10nm and 500nm particles showed that the magnitude of change for the majority of genes correlated more tightly with particle surface area than either particle mass or number. Gene expression changes that were size-specific were also identified, however the overall biological processes represented by all gene expression changes were nearly identical, irrespective of particle diameter. Our results suggest that on an equivalent nominal surface area basis, common biological modes of action are expected for nano- and supranano-sized silica particles. Experiment Overall Design: RAW 264.7 mouse macrophage cells were treated with two sizes of amorphous silica particles at three doses each for 2 hours. Cells were exposed to 10nm silica at 5 (low), 20 (mid), or 50 (high) ug/ml or 500nm silica at 250 (low), 500 (mid), or 1000 (high) ug/ml in serum-free medium.
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: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:Purpose:The goal of this study is to asses the gene expression changes in non-stimulated mast cell and anti-IgE-stimulated mast cell Methods:RBL-2H3 mRNA profiles of non-stimulated mast cell and anti-IgE-stimulated mast cell were generated by deep sequencing, in triplicate. Differential expression analysis was performed using the DESeq2(v1.4.5) with Q value ≦0.05, following the heatmap was drawn by pheatmap(v1.0.8) . Results:Compared with non-stimulated mast cell, anti-IgE-stimulated mast cell induced a robust transcriptional response, with 191 differentially expressed genes following anti-IgE treatment (116 upregulated and 75 downregulated). Among the up-regulated genes. Conclusions:Our study represents the first detailed analysis of RBL-2H3 transcriptomes, with biologic replicates, generated by RNA-seq technology.
Project description:RNA microarray was performed to evaluate the efficacy of silicon nano-particles on renal transcriptomes of rats against ischemia reperfusion injury. We compared the transcriptomes of ischemia reperfusion injury model rats with or without oral administration of silicon nano-particles. We also tried to check whether the oral silicon nano-particles intake downregulated the biological processes related to oxidative stress.
Project description:The toxicity and toxicogenomics of selected anatase and rutile nanoparticles (NP) and bulk titanium dioxide (TiO2) particles were evaluated in the soil nematode Caenorhabditis elegans. Results indicated that bulk or nano-TiO2 particles were slightly toxic to soil nematode C. elegans, as measured by reproduction EC50 values ranging from 4 to 32 mg/L. Whole-genome microarray results indicated that the regulation of glutathione-S-transferase gst-3, cytochrome P450 cypp33-c11, stress resistance regulator scl-1, oxidoreductase wah-1, and embryonic development pod-2 genes were significantly affected by nano-sized and bulk TiO2 particles. More specifically, it was determined that anatase particles exerted a greater effect on metabolic pathways, whereas rutile particles had a greater effect on developmental processes. The up-regulation of the pod-2 gene corroborated the phenotypic effect observed in the reproduction test. Our results demonstrated that C. elegans is a good genomic model for nano-TiO2 toxicity assessment.