Project description:Gene expression profiles of peripheral blood samples from C57BL/6 mice exposed with ionizing radiation. We used mice as model animal to study biologial recovery response after radiation damage. Therefore, we obtained gene expression profiles from C57BL/6 mice exposed with various levels of ionizing radiation, including low and high doses and control groups. In order to measure recovery rate, we collected peripheral blood samples at different time durations after the exposure. In order to obtain robust signatures specific to radiation response, we are interested in knowing if the radiation signarures will be present in the presence of confounders. Therefore, mice were given intraperitoneal injections of lipopolysaccharide endotoxin (LPS), or treated with granulocyte colony-stimulating factor (GCSF), otherwise no treatment after ionizing radiation exposure. The underlying mechanism of confounder treatment is that LPS induces strong immune response resembling the effect of infection, and GCSF stimulates mobilization of HSCs. Exploratory analysis shows that the confounding effects did affect the radiation signature to some extent. This study provides insights into the molecular basis of time- and dose- dependent response to ionizing radiation in mice hematopoietic system. A total of 536 C57BL/6 mice peripheral blood gene expression profiles were measured in 3 different batches using the Affymetrix mouse 430A 2.0 microarray. The experiment is designed to assess blood gene expression changes after exposure to ionizing radiation of 0, 100, 150, 200, 300, 450, 600, 800 and 1050 cGy. Samples were collected at 6, 24, 48, 72, 120 and 168hrs after a single dose exposure.
Project description:For around ten years, microarrays have been suggested for the diagnosis of ionizing radiation exposure. We assessed for the first time the relevance of gene expression profiling in a real accidental case. This study was performed on peripheral blood mononuclear cells of 41 potential victims. The different strategies of analysis highlighted a huge effect of the blood sample handling on the gene expression profiles. This effect was so high that it could mask specific modulations as a potential effect of ionizing radiation exposure. Thus, we assessed a new way of blood sampling adapted to gene expression analysis: PAXgene. With this method, more than 70% of the modulations of gene expression induced 3 hours after an ex vivo exposure to 0.5 Gy were preserved even in a 24-hour delayed analysis (as for transportation of blood sample from the accident location to the laboratory). We validated a new methodology in order to propose a new strategy of blood sampling and handling for gene profiling. This system could be used in case of accidental overexposure to study whether gene expression is a relevant biomarker of ionizing radiation exposure. Radiation induced gene expression in human blood was measured at 3 hours after exposure to doses of 0 and 0.5 grays. Following the incubation of 3 hours at 37°C, the RNA extractions were performed either immediately or 24h later (as for transportation of blood sample at room temperature). Two different blood preservation methods were compared: classical anticoagulant and PAXgene Blood RNA System. Venous blood samples of 6 donors were used (3 for anticoagulant study, 3 for Paxgene study). Each sample was hybridized twice.
Project description:For around ten years, microarrays have been suggested for the diagnosis of ionizing radiation exposure. We assessed for the first time the relevance of gene expression profiling in a real accidental case. This study was performed on peripheral blood mononuclear cells of 41 potential victims. The different strategies of analysis highlighted a huge effect of the blood sample handling on the gene expression profiles. This effect was so high that it could mask specific modulations as a potential effect of ionizing radiation exposure. Thus, we assessed a new way of blood sampling adapted to gene expression analysis: PAXgene. With this method, more than 70% of the modulations of gene expression induced 3 hours after an ex vivo exposure to 0.5 Gy were preserved even in a 24-hour delayed analysis (as for transportation of blood sample from the accident location to the laboratory). We validated a new methodology in order to propose a new strategy of blood sampling and handling for gene profiling. This system could be used in case of accidental overexposure to study whether gene expression is a relevant biomarker of ionizing radiation exposure.
Project description:Previous work has demonstrated the potential for peripheral blood (PB) gene expression profiling for the detection of disease or environmental exposures. We have sought to determine the impact of several variables on the PB gene expression profile of an environmental exposure, ionizing radiation, and to determine the specificity of the PB signature of radiation versus other genotoxic stresses. Keywords: peripheral blood, gene expression study, radiation reponse We have sought to determine the impact of several variables on the PB gene expression profile of an environmental exposure, ionizing radiation, and to determine the specificity of the PB signature of radiation versus other genotoxic stresses. Neither genotype differences nor the time of PB sampling caused any lessening of the accuracy of PB signatures to predict radiation exposure, but sex difference did influence the accuracy of the prediction of radiation exposure at the lowest level (50 cGy). A PB signature of sepsis was also generated and both the PB signature of radiation and the PB signature of sepsis were found to be 100% specific at distinguishing irradiated from septic animals. We also identified human PB signatures of radiation exposure and chemotherapy treatment which distinguished irradiated patients and chemotherapy-treated individuals within a heterogeneous population with accuracies of 90% and 81%, respectively. Human and Murine samples used in models Peripheral blood was collected from patients prior to and 6 hrs following total body irradiation with 150 to 200 cGy as part of their pre-transplantation conditioning. For additional comparison, peripheral blood was obtained from healthy volunteers and an additional cohort of patients prior to and 6 hrs following the initiation of alkylator-based chemotherapy alone (without radiotherapy).
Project description:Ionizing Radition is known to cause cell damage. Human peripheral blood mononuclear cells have long been used to study radiation induced gene expression profiling. Whithin this study we evaluated gene and microRNA expression alterations of human PBMC irradiated with 60 Gy g-ray. Cells were cultured for 2, 4 and 20h after irradiation before RNA was isolated and Agilent Human microRNA Microarrays was performed. Radiation induced gene expression in human peripheral blood mononuclear cells were measured at 2, 4 and 20 hours after exposure to doses of 60 Gy g-rays. Non radiated cell of each donor and time point were used as contol cells. Four independent experiments were performed at each time (2, 4, or 20 hours and 0 h - only 1 sample per donor) using 4 different donors.
Project description:Ionizing Radition is known to cause cell damage. Human peripheral blood mononuclear cells have long been used to study radiation induced gene expression profiling. Within this study we evaluated gene and microRNA expression alterations of human PBMC irradiated with 60 Gy g-ray. Cells were cultured for 2, 4 and 20h after irradiation before RNA was isolated and Agilent whole human GenomeOligo Microarray was performed. Radiation induced gene expression in human peripheral blood mononuclear cells were measured at 2, 4 and 20 hours after exposure to doses of 60 Gy g-rays. Non radiated cell of each donor and time point were used as contol cells. Four independent experiments were performed at each time (2, 4, or 20 hours and 0 h - only 1 sample per donor) using 4 different donors.
Project description:Previous work has demonstrated the potential for peripheral blood (PB) gene expression profiling for the detection of disease or environmental exposures. We have sought to determine the impact of several variables on the PB gene expression profile of an environmental exposure, ionizing radiation, and to determine the specificity of the PB signature of radiation versus other genotoxic stresses. Keywords: peripheral blood, gene expression study, radiation reponse
Project description:Ionizing radiation exposure from a potential nuclear energy plant leak or detonation of a nuclear weapon can cause massive casualties to both warfighters and civilians. Biomarkers in biological specimens like blood and tissue, such as RNA, proteins, and metabolites, have shown potential to determine radiation dose levels. However, these biomarkers in blood and urine are short-lived, typically detectable only within hours or a few days. To address the need for stable, long-term radiation exposure biomarkers, we developed two LC-MS-based methods using non-invasive hair samples to identify radiation-induced biomarkers