Here, we tested this hypothesis using exogenous miR-146a mimics and a mouse model of MS, experimental autoimmune encephalomyelitis (EAE) induced by immunization with myelin proteolipid protein peptide (PLP139-151).  EAE mice were treated by miR-146a mimics or miR-146a mimic negative controls, respectively, which initiated at day 14 post immunization, once a week for 6 consecutive weeks.  Using a fluorescence tracing approach, we found that miR-146a mimics crossed the blood brain barrier and targeted OPCs and microglia/macrophages after systemic administration. 
MiR-146a mimics