S1P modulation reduces transmigration of PBMCs across an in vitro BBB model under shear stress. When hBMVEC/hAST co-culture was exposed to T I in the presence of S1P (50 nM), pFTY (50 nM), or AUY (50 nM), the ability of PBMCs to migrate through the barrier is reduced if compared to the condition in which the barrier is exposed only to cytokines. Data are mean of 2 independent experiments and are expressed as percent reduction in PBMC migration after 1 hour compared to T I. *p