We have investigated the CSF levels of NfL in NTZ-treated MS patients and we have simultaneously demonstrated that plasmacytoid dendritic cells (pDCs) exhibit tolerogenic molecules such as HLA-G+ and CD274+ [also named programmed death-ligand 1 (PD-L1)] either in peripheral blood or in CSF during this therapy. Here, NEFL is linked to myeloid sarcoma.