Process for preparing a cell suspension

1. A process for carrying out an in vitro biochemical reaction for preparing a cell suspension suitable for application to the skin of a patient, the process comprising:

i) activating a warmer, the operation of which is based on an exothermic physical or chemical process,

ii) bringing said warmer into contact with a container containing a solution comprising trypsin by placing the warmer and at least the lower part of the container in a cavity of a support,

iii) placing a skin tissue sample comprising cells suitable for grafting to the skin of the patient in the solution comprising trypsin and incubating at from 30° C. to 40° C. for at least five minutes, and

iv) isolating cells disassociated from the skin sample and suspending the cells in a solution, to thereby provide a cell suspension suitable for application to the skin of a patient.

2. The process as claimed in claim 1 , wherein the contact between the warmer and the container is maintained for at least 10 minutes.

3. The process as claimed in claim 1 , wherein the volume of the solution comprising trypsin is from 3 and to 10 ml, the container containing said solution comprising trypsin is a Petri dish having a diameter of from 7 to 11 cm or a compartment of said dish and wherein the warmer is a disk of which the thickness is from 3 to 7 mm and the diameter is from 7 to 11 cm.

4. The process as claimed in claim 1 , wherein the cavity of the support is circular, with a diameter from 7 to 11.5 cm, and a depth from 5 to 20 mm.

5. The process as claimed in claim 1 , wherein the solution containing trypsin has a concentration of trypsin of from 0.2% to 1%.

6. The process as claimed in claim 1 , wherein the cells isolated in iv) are melanocytes.

7. The process as claimed in claim 1 , wherein the warmer comprises a hermetic plastic pouch containing a sodium acetate-saturated aqueous solution.

8. The process as claimed in claim 7 , wherein the incubating in iii) is at from 30° C. to 37° C. for at least five minutes.

9. The process as claimed in claim 8 , wherein the contact between the warmer and the container is maintained for at least 10 minutes.

10. The process as claimed in claim 8 , wherein the volume of the solution comprising trypsin is from 3 and to 10 ml, the container containing said solution comprising trypsin is a Petri dish having a diameter of from 7 to 11 cm or a compartment of said dish and wherein the warmer is a disk of which the thickness is from 3 to 7 mm and the diameter is from 7 to 11 cm.

11. The process as claimed in claim 8 , wherein the cavity of the support is circular, with a diameter from 7 to 11.5 cm, and a depth from 5 to 20 mm.

12. The process as claimed in claim 8 , wherein the solution containing trypsin has a concentration of trypsin of from 0.2% to 1%.

13. The process as claimed in claim 8 , wherein the cells isolated in (iv) are melanocytes.

14. The process as claimed in claim 8 , wherein the hermetic plastic pouch contains a supercooled sodium acetate-saturated aqueous solution.