CELL PREPARATION METHOD, CELL CULTIVATION DEVICE, AND KIT

1 . A method for preparing cells, the method comprising the step of: applying cells to a porous polyimide film and culturing the cells;

wherein the porous polyimide film is a three-layer structure porous polyimide film having a surface layer A and a surface layer B, the surface layers having a plurality of pores, and a macrovoid layer sandwiched between the surface layers A and B;

wherein an average pore diameter of the pores present in the surface layer A is smaller than an average pore diameter of the pores present in the surface layer B;

wherein the macrovoid layer has a partition wall bonded to the surface layers A and B, and a plurality of macrovoids surrounded by the partition wall and the surface layers A and B;

wherein the pores in the surface layers A and B communicate with the macrovoids; and

wherein the polyimide porous is produced by a method comprising the steps of:

(1) casting a poly(amic acid) solution consisting of a poly(amic acid) and an organic polar solvent into a film-like shape, and dipping in or bringing it into contact with a coagulating solvent to prepare a porous film of poly(amic acid); and

(2) imidizing the porous film of the poly(amic acid) obtained in the step (1) by heat treatment.

2 . The method for preparing cells according to claim 1 , wherein the porous polyimide film is produced by a method comprising the steps of:

(1) casting a poly(amic acid) solution consisting of a poly(amic acid) and an organic polar solvent into a film-like shape, and dipping in or bringing it into contact with a coagulating solvent to prepare a porous film of poly(amic acid);

(2) imidizing the porous film of the poly(amic acid) obtained in the step (1) by heat treatment; and

(3) subjecting at least one surface of the porous polyimide film obtained in the step (2) to plasma treatment.

3 . The method for preparing a cell according to claim 1 or 2 , wherein the poly(amic acid) comprises at least one tetracarboxylic dianhydride selected from the group consisting of biphenyltetracarboxylic dianhydride and pyromellitic dianhydride; and at least one diamine selected from the group consisting of benzenediamine, diaminodiphenyl ether and bis(aminophenoxy)phenyl.

4 . The method according to any one of claims 1 to 3 , the method comprising the step of: seeding cells on the surface of the porous polyimide film.

5 . The method according to any one of claims 1 to 3 , the method comprising the steps of:

placing a cell suspension on the dried surface of the porous polyimide film;

allowing the porous polyimide film to stand, or moving the porous polyimide film to promote efflux of liquid, or stimulating a part of the surface to cause absorption of the cell suspension into the film; and

retaining cells in the cell suspension in the porous polyimide film, and allowing water to flow out.

6 . The method according to any one of claims 1 to 3 , the method comprising the steps of:

wetting one or both sides of the porous polyimide film with a cell culture medium or a sterilized liquid;

loading a cell suspension into the wetted porous polyimide film; and

retaining cells in the cell suspension inside the film, and allowing water to flow out.

7 . The method according to claim 6 , wherein living cells remain within the porous polyimide film, and dead cells flows out with the water.

8 . The method according to claim 6 or 7 , wherein the sterilized liquid is a sterile water or a sterilized buffer solution.

9 . The method according to any one of claims 1 to 8 , the method comprising the step of:

placing a cell culture medium, cells, and one or more of the porous polyimide films in a cell culture vessel, wherein the porous polyimide films are in a suspended state in the cell culture medium.

10 . The method according to claim 9 , characterized in that two or more pieces of the porous polyimide films are used.

11 . The method according to claim 9 or 10 , wherein the cells spontaneously adhere to the porous polyimide film.

12 . The method according to any one of claims 1 to 8 , wherein the porous polyimide film is

i) folded,

ii) wound into a roll-like shape,

iii) connected as sheets or pieces with a filamentous structure, or

iv) bound into a rope-like shape,

and suspended or fixed in a cell culture medium in a cell culture vessel.

13 . The method according to claim 12 , wherein cells spontaneously adhere to the porous polyimide film.

14 . The method according to any one of claims 1 to 3 , the method comprising using two or more porous polyimide films are layered either above and below or left and right in the cell culture medium.

15 . The method according to any one of claims 1 to 3 , wherein two or more of the methods according to any one of claims 4 to 14 are conducted in combination.

16 . The method according to any one of claims 1 to 15 , wherein cells grow and proliferate on the surface and the inside of a porous polyimide film.

17 . The method according to any one of claims 1 to 16 , wherein the cells are selected from the group consisting of animal cells, insect cells, plant cells, yeasts and bacteria.

18 . The method according to claim 17 , wherein the animal cells are cells derived from an animal belonging to the vertebrate phylum.

19 . The method according to claim 17 , wherein the bacteria are selected from the group consisting of lactic acid bacteria, Escherichia coli, Bacillus subtilis and cyanobacteria.

20 . The method according to any one of claims 1 to 16 , wherein the cells are selected from the group consisting of pluripotent stem cells, tissue stem cells, somatic cells and germ cells.

21 . The method according to any one of claims 1 to 16 , wherein the cells are selected from the group consisting of sarcoma cells, established cells and transformed cells.

22 . A cell culture apparatus for use in a method for preparing cells according to any one of claims 1 to 21 , the apparatus comprising a porous polyimide film.

23 . The cell culture apparatus according to claim 22 , wherein two or more porous polyimide films are layered either above and below or left and right.

24 . A kit for use in a method for preparing cells according to any one of claims 1 to 21 , the kit comprising a porous polyimide film.