Co-expression of SphK1 and GFAP on reactive astrocytes in MS lesions and their borders was confirmed by double immunostaining (Fig. 2B), and SphK1 expression on macrophages in MS lesions, lesion borders and around blood vessels was confirmed by double immunostaining for SphK1 and CD68 (Fig. 2C, D). This evidence concerns the gene GFAP and myeloid sarcoma.