Figure 3.

(a) alkaline phosphate (ALP) activity and (b) osteocalcin concentration in static-state, spinner-flask, and flow-reactor culture systems. The hMSCs cultured in the flow reactor had relatively lower ALP activity than those of the spinner-flask and static-state culture in the first two weeks; however, the ALP level increased dramatically at week three. Regarding the osteocalcin concentration, both the static-state and spinner-flask cultures had relatively higher levels in the first week and decreased gradually through the study while the static state had an extremely high level of osteocalcin at week four. Otherwise, the flow reactor maintained a stable osteocalcin concentration.