Thorax irradiation of Non-Human Primates induces persistent gene expression changes in blood cells.. Macaca mulatta

In the current study, we investigated the gene expression response of blood cells of non-human primates that were whole thorax irradiated with a 10.1 Gy total dose. Partial irradiation of the NHP in the upper half of the body allows study of late radiation lung injury while avoiding acute respiratory syndromes related to hematopoietic and gastrointestinal injury. In this study, we report gene expression changes in the peripheral blood, an easily biopsied tissue, up to a month after radiation injury to the lungs. We isolated total RNA from peripheral blood at 3 days before irradiation, and then from the same animals on days 2, 5 and 30 after irradiation. Using Agilent Human Whole Genome microarrays, we identified 1187 genes that were significantly differentially expressed across the 30-day time course of this study. We identified common biological functions affected that persisted across the 30-day study, such as immune response. Response to oxygen-containing compounds and bacterial molecules were implicated by the gene expression changes at both the earliest day 2 and last, day 30 time-point and suggest that although cells are being recycled through the body in a 30-day time course after exposure to irradiation, the damage to blood cells and immunity, specifically the response to infections might persist throughout the study . Overall design: Radiation induced gene expression was measured at 2, 5 and 30 days after partial (upper) body irradiation. There were 5 replicates in this study.