TREM2 and neurodegenerative disease: Microglia in cluster 2 were uniquely enriched in genes associated with neurodegenerative diseases (TREM2, GLUL, S100A; Keren-Shaul et al., 2017; Krasemann et al., 2017; Cristóvaõ and Gomes, 2019) and immune activated microglia (CD63, HLA genes, CD14, TSPO; Beschorner et al., 2002; Kamphuis et al., 2016; Beckers et al., 2018) and in ribosomal genes (RPL genes; Figure 3D, Supplementary Tables S6, S7).