Use of depth filtration in series with continuous centrifugation to clarify mammalian cell cultures

1. A method for separating therapeutic proteins from an industrial scale cell sample comprising:

(a) centrifuging the cell sample at a gravitational force of from about 8,000×g to about 15,000×g and a Q/Σ ratio of about 1×10 −8 m/s, wherein the centrifugation separates the cells and cellular debris from the centrate which comprises the therapeutic proteins; and

(b) applying the centrate to a depth filtration means so as to recover a filtrate which comprises the therapeutic proteins, wherein the depth filtration means is effective to separate remaining particulate matter from the filtrate comprising the therapeutic proteins.

2. The method of claim 1 , wherein the gravitational force is in the range of about 8,000×g to about 12,000×g.

3. The method of claim 1 , wherein the gravitational force is in the range of about 8,000×g to about 10,000×g.

4. The method of claim 1 , wherein the gravitational force is in the range of about 10,000×g to about 15,000×g.

5. The method of claim 1 , wherein the gravitational force is in the range of about 12,000×g to about 15,000×g.

6. A method for separating therapeutic proteins from an industrial scale cell sample, comprising:

(a) centrifuging the cell sample at a gravitational force of from 8,000×g to 12,000×g and a Q/Σ ratio in the range of from 0.9×10 −8 m/s to 2.8×10 −8 m/s, wherein the centrifugation separates the cells and cellular debris from the centrate which comprises the therapeutic proteins; and

(b) applying the centrate to a depth filtration means so as to recover a filtrate which comprises the therapeutic proteins, wherein the depth filtration means is effective to separate remaining particulate matter from the filtrate comprising the therapeutic proteins.

7. The method of claim 6 , wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 1.8×10 −8 m/s.

8. The method of claim 6 , wherein the Q/Σ ratio is in the range of from 1.8×10 −8 to 2.6×10 −8 m/s.

9. The method of claim 6 wherein the gravitational force is in the range of from 8,000×g to 9,600×g, wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 2.7×10 −8 m/s.

10. The method of claim 9 , wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 1.8×10 −8 m/s.

11. The method of claim 9 , wherein the Q/Σ ratio is in the range of from 1.8×10 −8 to 2.7×10 −8 m/s.

12. A method for separating therapeutic proteins from an industrial scale cell sample, comprising:

(a) centrifuging the cell sample at a gravitational force of from 9,600×g to 15,000×g and a Q/Σ ratio in the range of from 0.9×10 −8 m/s to 2.8×10 −8 m/s, wherein the centrifugation separates the cells and cellular debris from the centrate which comprises the therapeutic proteins; and

(b) applying the centrate to a depth filtration so as to recover a filtrate which comprises the therapeutic proteins, wherein the depth filtration means is effective to separate remaining particulate matter from the filtrate comprising the therapeutic proteins.

13. The method of claim 12 , wherein the Q/Σ ratio in the range of from 0.9×10 −8 to 1.8×10 −8 m/s.

14. The method of claim 12 , wherein the Q/Σ ratio is in the range of from 1.8×10 −8 to 2.8×10 −8 m/s.

15. The method of claim 12 , wherein the gravitational force is in the range of from 12,000×g to 15,000×g, wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 2.8×10 −8 m/s.

16. The method of claim 15 , wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 1.8×10 −8 m/s.

17. The method of claim 15 , wherein the Q/Σ ratio is in the range of from 1.8×10 −8 to 2.8×10 −8 m/s.

18. The method of claim 12 , wherein the gravitational force is in the range of from 9,600×g to 12,000×g, wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 2.7×10 −8 m/s.

19. The method of claim 18 , wherein the Q/Σ ratio is in the range of from 0.9×10 −8 to 1.8×10 −8 m/s.

20. The method of claim 18 , wherein the Q/E ratio is in the range of from 1.8×10 −8 to 2.7×10 −8 m/s.