IL17A and myeloid sarcoma: Multiple IL-17A-producing cells, including CD4+ T cells, CD8+ T cells, and astrocytes, have been identified in the active plaques of MS patients’ brains (Tzartos et al. 2008); however, CD4+ T cells have been identified as the primary source of IL-17A in the EAE model (Komiyama et al. 2006).