To this end, translating methodologies from mouse models of MS that have allowed to image the inflammatory status of the BBB in vivo by MRI imaging making use of micro-sized particles of iron oxide (MPIO) targeting adhesion molecules including ICAM-1 [93, 94], will be beneficial to further advance the personalized dosing of NTZ in individual MS patients ensuring therapeutic efficacy while limiting the risk for PML. This evidence concerns the gene ICAM1 and myeloid sarcoma.