Patent ID: 7553612

Claim:
A method for cryopreserving living animal cells in immunoisolation membranes, comprising: (1) cutting out a piece of a living organ from an animal, (2) digesting the cutout piece into discrete living animal cells and separating the discrete cells, (3) suspending the separated cells in a solution of sodium chloride containing sodium alginate and collagen to obtain a suspension comprising cells (4) forming microcapsules of the living animal cells by gelling the cell suspension, (5) forming immunoisolation membranes around an outer surface of each of the microcapsules of the cells by covering the outer surfaces with alginate-(poly-L-lysine) to obtain enclosed cells, which are enclosed in the immunoisolation membranes, (6) suspending the enclosed cells in a cell damage-preventing solution to obtain a microcapsule suspension, and (7) cryopreserving the microcapsule suspension with liquid nitrogen by freezing the microcapsule suspension in the liquid nitrogen within 10 minutes after suspending the cells in (6) above to cryopreserve the cells, thereby cryopreserving the cells.