Cell culture apparatus and cell culture method

1. A cell culture apparatus comprising:

a culture vessel that stores a cell suspension containing cells;

a first filter part that has a first filter membrane that performs membrane separation treatment on the cell suspension extracted from the culture vessel;

a first circulation flow path that allows components blocked by the first filter membrane to return to the culture vessel;

a second filter part that has a second filter membrane that performs membrane separation treatment on components of the cell suspension permeated through the first filter membrane;

a second circulation flow path that allows components permeated through the second filter membrane to return to the culture vessel; and

a recovery flow path that recovers components blocked by the second filter membrane,

wherein an average hole diameter of the first filter membrane is from 0.05 μm to 20 μm, and

the second filter membrane is an ultrafiltration membrane having a molecular weight cut-off of 3 kDa or more.

2. The cell culture apparatus according to claim 1 ,

wherein a system of the membrane separation treatment by the second filter membrane is a dead end system, and

wherein the recovery flow path is provided between the first filter part and the second filter part.

3. The cell culture apparatus according to claim 1 ,

wherein a system of the membrane separation treatment by the second filter membrane is a tangential flow system, and

wherein the recovery flow path is connected to an outlet port of the second filter part by which components blocked by the second filter membrane flow outside the second filter part.

4. The cell culture apparatus according to claim 1 ,

wherein the first filter membrane has an inlet-side opening which is formed on a first surface, and an outlet-side opening which is formed on a second surface opposite to the first surface and is communicated with the inlet-side opening, and

the inlet-side opening and the outlet-side opening are disposed at positions mutually offset in a direction parallel to a membrane surface.

5. The cell culture apparatus according to claim 1 , wherein the first filter membrane is a microfiltration membrane.

6. The cell culture apparatus according to claim 1 , wherein a molecular weight cut-off of the second filter membrane is from 3 kDa to 100 kDa.

7. A cell culture method comprising:

a first membrane separation step of using a first filter membrane to perform membrane separation treatment on a cell suspension extracted from a culture vessel that stores the cell suspension containing cells, and allowing components blocked by the first filter membrane to return to the culture vessel;

a second membrane separation step of using a second filter membrane to perform membrane separation treatment on components permeated through the first filter membrane, and allowing components permeated through the second filter membrane to return to the culture vessel; and

a recovery step of recovering components blocked by the second filter membrane via a recovery flow path,

wherein an average hole diameter of the first filter membrane is from 0.05 μm to 20 μm,

wherein the second filter membrane has a molecular weight cut-off of 3 kDa or more, and

wherein 0<B/A≤0.5 is satisfied in a case where an average hole diameter of the first filter membrane is A, and an average hole diameter of the second filter membrane is B.

8. The cell culture method according to claim 7 , wherein 1.4<Y/X is satisfied in a case where a perfusion ratio, which is a ratio of an amount of components recovered in the recovery step per day to an amount of the cell suspension stored in the culture vessel, is X, and a circulation ratio, which is a ratio of an amount of components permeated through the first filter membrane in the first membrane separation step per day to the amount of the cell suspension stored in the culture vessel, is Y.

9. The cell culture method according to claim 8 , wherein the perfusion ratio is 0.09 to 1.9.

10. The cell culture method according to claim 7 ,

wherein a concentration of the cells contained in the cell suspension stored in the culture vessel is 2×10 7 cells/ml or more, and

a concentration of fine particles that have a particle diameter of 2 μm to 4 μm and are contained in the cell suspension stored in the culture vessel is 40×10 7 particles/ml or less.

11. The cell culture method according to claim 7 ,

wherein the cell is a cell that expresses an antibody, and

a concentration of the cells contained in the cell suspension stored in the culture vessel is 2×10 7 cells/ml or more, and a concentration of the antibodies contained in the cell suspension stored in the culture vessel is 4 g/l or less.

12. The cell culture method according to claim 7 , wherein a system of the membrane separation treatment by the first filter membrane is a tangential flow system.

13. The cell culture method according to claim 7 , wherein, in the recovery step, the components blocked by the second filter membrane is continuously sent to the recovery flow path.

14. The cell culture method according to claim 7 ,

wherein the cell is a cell that expresses an antibody, and

wherein a permeate liquid permeated through the second filter membrane comprises a growth factor.