IP Library Granted Patent US 12667099
Granted Patent B2
US 12667099 · App. 17/915,415 · Granted Jun 30, 2026

Cell preservation method

Inventors: Yasutomo Yanagita (Tokyo, JP); Chugo Rinoie (Tokyo, JP); Takefumi Ishidao (Tokyo, JP); Itsunari Minami (Tokyo, JP)
Assignee: Cell Exosome Therapeutics Inc.
A01N1/162A01N1/125A01N1/142A61K9/08A61K35/28A61K47/10A61K47/20C12N5/0663C12N2500/35C12N2500/62
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Quick Facts
Patent No.
US 12667099
App. No.
17/915,415
Granted
Jun 30, 2026
Kind
B2
Abstract

The purpose of the present invention is to obtain a cell suspension with a low concentration of cryoprotectant. This method of preserving cells used comprises the steps of (a) enriching cells from a cell suspension containing the cells and a cryoprotective solution to generate an enriched fraction, and (b) freezing the enriched fraction to prepare a frozen material. It is also possible to use a method of producing a cell suspension, comprising the steps of (a) enriching cells from a cell suspension containing the cells and a cryoprotective solution to generate an enriched fraction, (b) freezing the enriched fraction to prepare a frozen material, (c) thawing the frozen material to prepare a thawed material, and (d) mixing the thawed material and a solution to produce a cell suspension.

Claims (20)

1 . A bag containing a composition containing stem cells and a cryoprotectant, wherein the composition forms a cell pellet over a side within the bag.

2 . The bag according to claim 1 , wherein the cell pellet is formed by centrifuging the bag in a lateral lying position.

3 . The bag according to claim 1 , wherein the cell pellet is formed so that the cell pellet spreads over the side within the bag.

4 . The bag according to claim 1 , wherein the composition is a frozen composition.

5 . The bag according to claim 1 , wherein the composition contains 2.0×10 7 cells/mL or more cells.

6 . The bag according to claim 1 , wherein the composition contains 0.5 to 10% (v/v) of the cryoprotectant.

7 . The bag according to claim 1 , wherein said cell pellet is a cell pellet formed by centrifugation in which centrifugal force is directed toward the side of the bag.

8 . The bag according to claim 1 , wherein the cell pellet is a cell pellet formed over only one side within the bag.

9 . A device comprising a bag according to claim 1 and a syringe, wherein the bag and syringe are integrated.

10 . A method of producing a cell suspension for a method of regenerative medicine, comprising the step of adding a solution into the bag according to claim 1 to produce a cell suspension.

11 . A cell suspension for a method of regenerative medicine obtained by the production method according to claim 10 .

12 . A method of regenerative medicine, comprising administering to a subject a cell suspension containing a solution, cells, and a cryoprotectant, wherein the cell suspension is obtained by adding the solution into the bag according to claim 1 .

13 . The method according to claim 12 , comprises the step of

adding the solution into the bag, and

floating and suspending the cell pellet in the bag by hand unraveling.

14 . The method according to claim 12 , wherein the solution is saline or buffer solution.

15 . A method of producing a stem cell suspension for a method of regenerative medicine, comprising the steps of thawing a frozen composition forming a cell pellet over a side within a bag, wherein the cell pellet contains a frozen cryoprotectant and a frozen single cell population of 2.0×10 7 cells/ml or more cells to obtain a thawed composition, and adding a solution into the bag containing the thawed composition to produce a stem cell suspension.

16 . The method according to claim 15 , comprising floating and suspending the thawed composition by hand unraveling.

17 . A method of regenerative medicine, comprising administering to a subject a cell suspension containing a solution, cells, and a cryoprotectant, wherein the cell suspension is obtained by the method according to claim 15 .

18 . The method of regenerative medicine of claim 12 , wherein the cryoprotectant content is 0.5% (v/v) or less, and the concentration of cells is 1.0×10 5 cells/ml or more.