Fig 4. Influenza A/PR/8/34 virus propagation in AGE1.CR.pIX cells in batch and semi-continuous cultures.

A) HA titers (closed symbols) and TCID₅₀ titers (open symbols) of two batch cultures (diamond and square symbols). Batch cultures were initiated with cells of the CSTR of the continuous tubular bioreactor system (see Fig 1) after termination of continuous cultivations. B) Influenza HA titers (closed diamonds) and TCID₅₀ titers (open symbols) of a semi-continuous culture performed in shake flasks as described previously [6].