Microglial transcriptional profiles of a transgenic rat model closely model Alzheimer's disease.

Single-cell RNA-sequencing has identified that Alzheimer's disease (AD) pathology in humans is associated with activation of disease-associated microglia (DAM). Microglial signatures of human AD have not been consistently identified in AD mouse models. Since the inflammatory response of rats is more like humans, we profiled microglial transcriptomes in aging TgF344-AD rats, which overexpress two human AD risk genes. Classic DAM gene activation (ApoE, Trem2, Gpnmb), and upregulation (MHC class-II) and downregulation (Ifngr1 and Fkbp5) of human AD microglial genes were identified in aging TgF344-AD rats. Thus, the TgF344-AD rat better recapitulates the microglial gene signature observed in human AD.