The frequency of CD56+CCR4+ cells (NK17/NK1 cells) was about ten-fold higher than CD56−CCR4+ cells found in the CSF (Figure 5B vs. 5C), and more than twenty-fold the numbers of non-activated CD56+CCR4+ found in the peripheral blood of MS patients (Figure 5B vs. 5A). The gene discussed is CCR4; the disease is myeloid sarcoma.