Unknown,Transcriptomics,Genomics,Proteomics

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Gene expression variation in lymphocyte subpopulations in response to low dose of ionizing radiations

ABSTRACT: Lymphocytes are the standard cell of a majority of biodosimetry approaches because of their availability and radiosensitivity. But progresses remain to be performed to bring down the minimum threshold of dose sensitivity. To find a lymphocyte subtype able to respond to low doses of ionizing radiation, we examined gene expression variations in different lymphocyte subpopulations using the microarray technology. Blood samples were independently exposed to 0, 0.05 and 0.5 Gray of ionizing radiations. Three and 24 hours after exposure, CD56+, CD4+ and CD8+ cells were negatively isolated. RNA from each condition was competitively hybridized on oligonucleotide microarrays. Keywords: Dose response, stress response, cell type comparison We characterized genes whose expression level was affected following exposure to γ rays by carrying out genome-wide expression profiling on each lymphocyte subpopulation. Total blood samples were collected from 5 healthy male donors. Each sample was splitted into three parts which were exposed respectively to 0 Gy (sham-irradiated), 0.05 Gy and 0.5 Gy of ionizing radiations. Lymphocytes subpopulations were sorted 3 and 24 hours after irradiation. RNA was prepared from each cell type and amplified. The amino-allyl amplified RNAs were labeled and independently hybridized to the array. RNA from MNC obtained from 20 independent healthy donors constituted the reference group for competitive oligonucleotide microarray hybridization. According to our criteria of quality, we considered a total of 114 microarrays

ORGANISM(S): Homo sapiens

SUBMITTER: Gaëtan GRUEL

PROVIDER: E-GEOD-6978 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Broad modulation of gene expression in CD4+ lymphocyte subpopulations in response to low doses of ionizing radiation.

Gruel Gaëtan G Voisin Pascale P Vaurijoux Aurélie A Roch-Lefevre Sandrine S Grégoire Eric E Maltere Peggy P Petat Cyrille C Gidrol Xavier X Voisin Philippe P Roy Laurence L

Radiation research 20080901 3

To compare the responses of the different lymphocyte subtypes after an exposure of whole blood to low doses of ionizing radiation, we examined variations in gene expression in different lymphocyte subpopulations using microarray technology. Blood samples from five healthy donors were independently exposed to 0 (sham irradiation), 0.05 and 0.5 Gy of ionizing radiation. Three and 24 h after exposure, CD56+, CD4+ and CD8+ cells were negatively isolated. RNA from each set of experimental conditions ...[more]

PMID: 18763857

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Dataset Information

Gene expression variation in lymphocyte subpopulations in response to low dose of ionizing radiations

Publications

Broad modulation of gene expression in CD4+ lymphocyte subpopulations in response to low doses of ionizing radiation.

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