HLA-DRA and myeloid sarcoma: While confirming increased expression of genes involved in antigen presentation (HLA-DRA), phagocytosis (CD68, MSR1) and immunoregulation (IL10) in the NAWM, this study differs from previous studies showing more limited or no changes in the expression of inflammation- and microglia-related genes in NAWM samples isolated from the brain of acute (Zrzavy et al., 2017), relapsing-remitting (Hendrickx et al., 2017) and progressive (Koning et al., 2007; Zeis et al., 2008; Elkjaer et al., 2019) MS cases, and in microglia isolated from the NAWM of progressive MS cases (van der Poel et al., 2019).