The transcriptomic profile of the hippocampal microglia in the irradiated juvenile mouse brain

Cranial irradiation (IR), an effective tool to treat malignant brain tumors, triggers a chronic pro-inflammatory microglial response, at least in the adult brain. Using bulk RNA sequencing, we show that the microglial response in the juvenile mouse hippocampus is rapid, but returns toward normal within 1 week. The sensome of irradiated hippocampal microglia reveals an immediate response that declines after one day. Irradiation of the juvenile brain induces a highly ordered temporal progression of the inflammatory and phenotypic microglial genes Overall design: Mice were irradiated on postnatal-day 21 with radiation dose of 8Gy. Miced were sacrifced at different time points after irradiation (2h, 6h, 1day, and 1wk). After perfusion, the hippocampus was dissected and the micgloa were FACS isolated based on the expression of Cx3cr1 expression. Total RNA was isloated and processed for bulk RNA-Seq. Each time point consisted iof 6 sham control (SH) and 6 irradiated (IR) animals.