The use of caged aeration for the growth of animal cells on microcarriers.

A simple, unaerated 0.1 litre microcarrier propagator was successfully sealed up to 1 litre using constant tip speed of the flexible wide blade stirrer. Further scale-up to 10 litres was not successful because of inadequate aeration. When this deficiency was corrected, using a sintered aerator, cell growth did not improve due to excessive foam production. This was overcome by carrying out the necessary aeration inside a special cage, located inside the propagator, which retained the bubbles and excluded the microcarriers. Using this device cell growth improved to levels similar to those obtained at the 0.1 and 1 litre scales.