Figure 6.

Extracellular S1P stimulates osteoblast chemotaxis and survival. (A) Mouse calvarial osteoblasts were treated with 10 nM FTY-720 or vehicle, and allowed to migrate for 24 h towards 0.01–1 μM S1P using transwell plates. (B) Osteoblasts were allowed to migrate for 24 h towards the indicated CM diluted at the indicated ratio. (C) Osteoblasts were allowed to migrate for 24 h towards the indicated CM. (D) Osteoblasts were incubated with S1P in serum-free media for 72 h. The number of surviving cells was counted after hematoxylin staining. (E) Osteoblasts were collected and S1P receptor mRNA was detected by RT–PCR. (F) T cells were allowed to migrate for 3 h towards the indicated CM. (G) T cells were allowed to migrate for 3 h in the presence of FTY-720 towards the indicated CM diluted at 1:1 ratio.