Cryopreservation, hibernation and room temperature storage of encapulated pancreatic endoderm cell aggregates

A method for producing insulin in vivo in a mammal, said method comprising:

• a. obtaining an in vitro human pancreatic cell aggregate population;
• b. loading the pancreatic cell aggregate population into an implantable semi-permeable encapsulation device thereby making an encapsulated pancreatic cell population;
• c. contacting the pancreatic cell population with cryopreservative thereby cryopreserving the encapsulated pancreatic cell population;
• d. thawing the encapsulated pancreatic cell population;
• e. implanting the encapsulated pancreatic cell population into a mammalian host;
• and
• f. maturing the encapsulated pancreatic cell population in vivo to form a mature cell population comprising of endocrine and acinar cells, wherein at least some of the endocrine cells are insulin secreting cells that produce insulin in response to glucose stimulation in vivo, thereby producing insulin in vivo to the mammal.