Medium for preparing dedifferentiated cells

An in vitro method for producing cells with at least bipotentiality, which comprises the steps of:

• a) inducing cystic formation in cells cultured in a medium of the present invention, wherein said cells are selected from the group consisting of acinar cells and cells derived from post-natal islets of Langerhans cells from a patient to obtain a duct-like structure;
• whereby when the duct-like structure cells are introduced in situ in the patient, the cells are expanded and islet cell differentiation properties are induced to become in situ insulin-producing cells.

A method for the treatment of diabetes mellitus in a patient, which comprises the steps of

• a) inducing cystic formation in cells cultured in a medium of the present invention, wherein said cells are selected from the group consisting of acinar cells and cells derived from post-natal islets of Langerhans cells of the patient to obtain a duct-like structure;
• and
• b) introducing the duct-like structure cells in situ in the patient, wherein the cells are expanded in situ and islet cell differentiation properties are induced in situ to become insulin-producing cells.

A medium for inducing islet neogenesis from duct-like structure, which comprises in a physiologically acceptable culture medium an effective amount of at least one islet neogenesis inducer compound selected from the group consisting of gastrin, hepatocyte growth factor (HGF), epidermal growth factor, transforming growth factor-β1, transforming growth factor-β2, transforming growth factor-β3, insulin-like growth factor-1, insulin-like growth factor-2, insulin, nerve growth factor, keratinocyte growth factor, nicotimanide and insulin-transferrin-sodium selenite.