ITGA4 and myeloid sarcoma: Although, in our study, RR-MS as well as HC CD49d+CD154+ lymphocytes had no effect on miR-219, and other miRNA molecules involved in OPC maturation (miR-338, miR-138, miR-29, miR-32), we cannot exclude that they are engaged in impaired myelin synthesis by OLs [21,41].