Three bioreactor system for the cultivation of mammalian cells

A bioreactor system for the cultivation of mammalian cells comprising:

• a first bioreactor having a volume of between 500 and 1000 l and at least one top impeller and at least one bottom impeller, connected to a second bioreactor, wherein the at least one top impeller is a hydrofoil impeller, wherein the first bioreactor has an aspect ratio between 0.17 to 1.96 and an impeller to tank diameter between 0.44 to 0.46,
• the second bioreactor having a volume of between 2000 and 4000 l and at least one top impeller and at least one bottom impeller, connected to a third bioreactor, wherein the at least one top impeller is a hydrofoil impeller, wherein the second bioreactor has an aspect ratio between 0.17 to 1.96 and an impeller to tank diameter between 0.44 to 0.46, and wherein the second bioreactor has a volume greater than the first bioreactor
• the third bioreactor having a volume of between 10 000 and 20 000 l and at least one top impeller and at least one bottom impeller, wherein the at least one top impeller is a hydrofoil impeller, wherein the third bioreactor has an aspect ratio between 0.17 to 1.96 and an impeller to tank diameter between 0.44 to 0.46, and wherein the third bioreactor has a volume greater than the second bioreactor,
• wherein the first, second or third bioreactor maintain a homogeneous environment with respect to pH, dissolved oxygen tension (DOT) and temperature, allows for a well-mixed cell suspension and a blending of nutrient feeds within the bioreactor, and
• wherein the first, second and third bioreactors are geometric similar.