MPs are a highly plastic population of different, though closely related cell types, which often convert into each other depending on the local milieu and activation status in particular in MS.15, 16 Currently we cannot yet pinpoint the precise subtype of MPs that interacts with CD8+ T cells in the MS lesions; however, we assume that CD8+ T cell may communicate with several subtypes because we found them in contact with CD163+CD11b+ and CD163−CD11b+ cells. Here, CD8A is linked to myeloid sarcoma.