Also the chemokine receptor CXCR3 on the lymphocyte surface seems to act in the patrolling of the CNS [18] and may play a role in MS pathogenesis [19] because it triggers rapid leukocyte adhesion and is induced in activated CD4+ and CD8+ T cells crossing the BBB [18–20]. Here, CXCR3 is linked to myeloid sarcoma.