Proliferation rates of HepG2 cells encapsulated in alginate are increased in a microgravity environment compared with static cultures.

This study investigates the effect of rotary culture compared with static culture on the proliferation, cell viability, synthetic function and detoxificatory capacity of HepG2 cells encapsulated in 1% alginate. Cell viability and alginate bead morphology were maintained in the rotary culture system at day 10, while cell number showed a 4.5-fold increase compared with static culture. Protein production was increased in rotary cultures with a 4.1-fold increase in total albumin and a 4.4-fold increase in alpha1 antitrypsin levels in rotary compared with static culture at day 10. CYP4501A1/2 activity was maintained between the two culture systems. In conclusion, rotary culture increases proliferation rates leading to improved bead packing and a concomitant increase in total protein synthesis, along with maintenance of detoxificatory capacity. This allows a greater level of hepatic function to be expressed in a given volume, offering clear advantages for the design of liver support systems.