Figure 1.

Schematic of Flow System. Cell-seeded media circulates from the attachment flask for the first 2 h, during which time both valves to and from the growth flask are closed. After 2 h, the valves to and from the attachment flask are closed and those of the growth flask are opened, allowing circulation of cell-free media for the remainder of the experiment (additional 16 h). Media is maintained as cell-free using four sequential filters. Arrows indicate direction of flow. PD: Pulsation Damper, used to reduce pulsation of slide surface caused by pump.