The therapeutic effect of FTY720 on experimental autoimmune encephalomyelitis in mice

FTY720, sphingosine 1-phosphate receptor agonist, induces lymphopenia by sequestration of circulating lymphocytes into secondary lymphoid tissues and shows a potent immunosuppressive activity. The experimental autoimmune encephalomyelitis (EAE) was induced by immunization with myelin proteolipid protein (PLP) to SLJ mice. The EAE was relapsed 2 weeks after primary EAE. The relapse of PLP-induced EAE was suppressed by the therapeutic oral administration of FTY720 at 0.1similar to1 mg/kg. In FTY720-treated groups, the area of demyelination and the number of CD4(+) T cells infiltrated into the spinal cord were decreased as compared with those in vehicle-treated control group. These results suggest that FTY720 provides a useful tool for the therapy of multiple sclerosis.