Cell Freezing Kits and Their Use Thereof

1 - 22 . (canceled)

23 . A cell freezing kit, comprising:

(i) a device equipped with a filter; and

(ii) a container having hermetic closing means, which is capable of containing the device equipped with a filter,

wherein the filter has hydrophobic properties and/or the kit also comprises a hydrophobic solution.

24 . The cell freezing kit of claim 23 , wherein the average diameter of the pores of the filter is between 2 and 10 microns.

25 . The cell freezing kit of claim 23 , wherein the filter has hydrophobic properties so that the freezing medium does not pass through the filter in the absence of a driving force greater than gravitational force.

26 . The cell freezing kit of claim 23 , which comprises a hydrophobic solution capable of passing through the filter only when a driving force greater than gravitational force is applied thereto.

27 . The cell freezing kit of claim 26 , wherein the hydrophobic solution is a solution of glycerol.

28 . The cell freezing kit of claim 26 , wherein the hydrophobic solution is a sterile oil free of endotoxins.

29 . The cell freezing kit of claim 23 , wherein the device equipped with a filter is a centrifugal filter.

30 . The cell freezing kit of claim 23 , wherein the hermetic closing means of the container comprise a screw cap.

31 . The cell freezing kit of claim 23 , wherein the assembly of the container and the device equipped with a filter constitutes a centrifugation unit suitable for centrifugation between 50 and 1500 g.

32 . The cell freezing kit of claim 31 , which comprises one or several centrifugation units, wherein said centrifugation units are sterile or sterilizable.

33 . A method for freezing cells using the device of claim 23 , comprising:

(i) introducing cells in a freezing medium in the device equipped with a filter;

(ii) putting the device equipped with a filter into the container;

(iii) hermetically closing the container; and

(iv) placing the container at a freezing temperature.

34 . The method of claim 33 , wherein step (ii) is performed before step (i).

35 . The method of claim 33 , wherein a drop of a hydrophobic solution is added to the filter before step (i).

36 . The method of claim 33 , wherein the device equipped with a filter and the container are sterilized before step (i).

37 . The method of claim 33 , wherein the amount of cells placed in each device equipped with a filter is between 10 4 and 10 7 .

38 . A method for thawing cells frozen using the device of claim 23 , comprising:

(i) placing the container, containing a frozen cell suspension in a device equipped with a filter, at a temperature which allows the cell suspension to thaw;

(ii) applying to the cell suspension a force which drives the passing of the freezing medium through the filter;

(iii) resuspending the cells in cell medium.

39 . The method of claim 38 , wherein step (ii) is performed by centrifugation.

40 . The method of claim 39 , wherein the centrifugation is performed during less than or equal to 10 minutes, at a speed which makes it possible to apply to the cell suspension an acceleration of between 50 and 1500 g, preferably between 100 and 200 g.