FTY720P is the bioactive form of the novel immunosuppressive drug fingolimod (FTY720). FTY720 is converted to FTY720P by sphingosine kinase and the (S)-isomer acts as an agonist to four S1P receptors (S1P1,3,4,5) with IC50s of 2.1, 5.9, 23 and 2.2 nM respectively. The R isomer binds with 5-10 fold lower affinity. FTY720P improves the survival of neonatal rat oligodendrocytes, regulates oligodendrocyte progenitor cells differentiation, promotes astrocyte migration via extracellular signal-regulated kinase (ERK) signaling. Recently published results indicate involvement of FTY720P in complete viral clearance of persistent infection caused by clone 13 of lymphotic choriomeningitis virus (LCMV). This item is non returnable