C5aR1+ microglia/macrophages in MS cortical GM co-stained for iNOS and TNFα and demonstrated cytoplasmic PLP, neurofilament + and synaptophysin + phagocytosed material and were in close proximity to C3b+ stressed/damaged cortical neurons (Figure 3; Watkins et al., 2016), suggesting that some of these cells contribute to worsening tissue damage. The gene discussed is NOS2; the disease is myeloid sarcoma.