CD8A and multiple sclerosis: Using scRNAseq to establish a detailed molecular description of microglia from HCs and multiple sclerosis patients, Masuda et al. 290 observed that the microglial profile from HCs was enriched for transcripts indicative of a homeostatic phenotype, while multiple sclerosis patients showed multiple activated subsets potentially indicating engagement with infiltrating autoreactive T cells, matrix remodelling or reduction of cytotoxic CD8+ T-cell functions.