Figure 4. Trem2^–/– microglia fail to upregulate transcripts implicated in activation, phagocytosis, and lipid metabolism in response to demyelination.

Gene expression analyses of FACS-sorted WT and Trem2^–/– microglia from control mice and mice fed with cuprizone diet for 4 or 12 weeks. (A) Scatter plot shows comparison of WT and Trem2^–/– microglial transcriptomes in steady state. Numbers indicate transcripts that are differentially expressed (fold change ≥ 2) between WT and Trem2^–/– microglia. The Trem2 transcript is indicated. (B) Transcriptional changes of WT microglia in response to cuprizone feeding for 4 weeks or 12 weeks compared with control (fold change ≥ 2 and ≤ 2). Numbers represent transcripts that are either differentially regulated at 4 weeks, 12 weeks, or both 4 and 12 weeks. (C) Heat map shows the expression of cuprizone-induced genes from B in WT and Trem2^–/– microglia. Selected transcripts are indicated. (D) Selected transcriptional changes (from C) were further validated by qPCR.