Project description:Quantifying impact of lead on cytokine production and gene expression in PBMCs Cells were treated with 10mkM lead acetate for one day, washed and grown in RPMI for the second day. Lead acetate was not added to matching control cells.
Project description:75 Diosophilia Roo lines, recominant inbred lines, were raised to adulthood either on conventional diet or diet supplemented with lead acetate. Whole flies were used for RNA extraction. RNA was run on Dros Genome 2 arrays. Each line also genotyped for 88 markers; Control food consisted of standard cornmeal, agar, sugar, yeast, and 250 microM NaAc (Ashburner 1989). Lead-contaminated food consisted of standard food plus 250 microM PbAc (lead exposure at this concentration has been shown to affect locomotion in adults (Hirsch et al. 2003)). Experiment Overall Design: 75 RI lines each line treated and untreated with lead acetate
Project description:Lead is a ubiquitous environmental and industrial pollutant. Its nonbiodegradable toxicity induces a plethora of human diseases. The current study was undertaken to purify a novel 252-kDa bioactive glycoprotein containing 1.15% carbohydrate from the edible fungus Auricularia polytricha with the ability of adsorbing lead and producing detoxification. The A. polytricha detoxifying glycoprotein (APL), which displayed unique molecular properties, was purified by ion exchange chromatography and gel filtration chromatography. For investigating the protective effects of A. polytricha, Sprague Dawley (SD) rats were divided into six groups which received daily intraperitoneal injection of lead acetate for 30 days, followed by gavage with APL (40, 80, 160 mg/kg B body weight) and EDTA (300 mg/kg body weight) for 30 days after successful establishment of an animal model of lead detoxification. The serum concentrations of lead and the liver biomarkers AST and ALT were significantly (p<0.05) improved by APL treatments, as well as treatment with the positive control EDTA. Likewise, results on lead residue showed that the clearance ratios of liver and kidney were respectively 44.5% and 18.1% at the high APL dosage, which was even better than the corresponding data for EDTA. Proteomics disclosed that 351 proteins differentially expressed due to lead exposure and the expression levels of 41 proteins enriched in the pathways mainly involved in cell detoxification and immune regulation were normalized after treatment with APL-H. Our results signify that APL may ameliorate lead-induced hepatorenal injury by positive regulation of immune processing, and suggest that APL be applied as a therapeutic intervention of lead poisoning in clinic treatment. This report represents the first demonstration of the protective action of a novel mushroom protein on lead-elicited hepatorenal toxicity.
Project description:Despite major successes in reducing the risks of lead (Pb) exposure over the past few decades, two issues of considerable importance remain unresolved: (1) how differences in water chemistry influence acute and chronic Pb toxicity, and (2) the elucidation of specific toxic mechanisms and modes of action (MOA). To more clearly define the water chemistry parameters mediating Pb toxicity we evaluated the effects of hardness (as CaSO4) and DOC (as humic acid (HA)) during chronic (150d) exposures to the fathead minnow (Pimephales promelas). Traditional toxicological endpoints were examined alongside gene expression analyses to help clarify the underlying mechanisms and MOA of Pb toxicity and to identify robust molecular markers of exposure and effect. Keywords: time course, chronic lead (Pb) exposure To analyze the gene expression responses to low-level Pb exposures fish were exposed +/- Pb in low ionic strength base water and fish collected at 2d, 4d, 10d, and 30d for microarray analysis. Equal amounts of RNA from all no lead controls were pooled (18 fish total for 2d & 4d exposures; 12 fish total for 10d & 30d exposures) as reference samples for hybridization with each of 3 separate biological replicate pools (6 fish total for 2d & 4d exposures; 4 fish total for 10d & 30d exposures) of RNA from age-matched, lead-exposed fish. Each pair of hybridizations was repeated with dye-swaps. Additional repeats were performed for various arrays to ensure quality of data obtained from initial hybridization.
Project description:Despite major successes in reducing the risks of lead (Pb) exposure over the past few decades, two issues of considerable importance remain unresolved: (1) how differences in water chemistry influence acute and chronic Pb toxicity, and (2) the elucidation of specific toxic mechanisms and modes of action (MOA). To more clearly define the water chemistry parameters mediating Pb toxicity we evaluated the effects of hardness (as CaSO4) and DOC (as humic acid (HA)) during chronic (150d) exposures to the fathead minnow (Pimephales promelas). Traditional toxicological endpoints were examined alongside gene expression analyses to help clarify the underlying mechanisms and MOA of Pb toxicity and to identify robust molecular markers of exposure and effect. Keywords: time course, chronic lead (Pb) exposure
Project description:Lead pollution is global, billions of people are chronically exposed to lead. Biological thiols are nature sequesters of lead. Human immune system is highly vulnerable to lead, unfortunately the underlying mechanism remains unknown. Using mass cytometry and mass spectrometry, we systematically identified lead targets in immune cells from mice model of chronic lead exposure. We found CD4+ T and neutrophil are most vulnerable to lead, respectively due to low thiol and high glutathione metabolism. Specifically, in CD4+ T, lack of thiol renders severe damage of ribosome by lead, which we successfully rescued using thiol drugs. In neutrophil, robust glutathione metabolism accumulates lead, which can be passed on to proteins of higher binding affinity. Among these proteins, our evidences suggest lead suppresses immune activation through PKC-like, PE/DAG-binding domain on RAF1 and PKCs. Overall, it clarified the mechanisms of toxicity in immune cells upon chronic lead exposure, which provides valuable information for medical care and public health.
Project description:Atherosclerosis has an auto-immune component driven by self-reactive T and B cells. Identifying their antigenic drivers may lead to new diagnosis and treatment approaches. Here, we aim to identify immunogenic T cell epitopes derived from atherosclerosis-relevant proteins such as ApoB100 by studying the repertoire of peptides presented by HLA in human plaques. We used immunopeptidomics to identify peptides presented by HLA-DR molecules in 51 plaques from patients that underwent endarterectomy surgery. We selected a set of 20 peptides derived from ApoB100 and studied the presence and cytokine profile of ApoB100-specific CD4+ T cells in peripheral blood mononuclear cells (PBMCs) from atherosclerosis patients. Results revealed significant CD4+ T cell activation in response to these ApoB100 peptides in 22.4% of the patients, and this T cell response correlated positively with plaque vulnerability. Furthermore, the cytokine profile of these cells was characterized by production both pro- and anti-inflammatory cytokines.