The long-term culture of encapsulated pancreatic islets

A new encapsulation technique, the formation of a polyelectrolyte complex membrane from sodium cellulose sulphate and a polycationic solution (polydimethyldiallylammoniumchloride) can be used for culturing pancreatic islets. After 5 weeks of culture, such encapsulated islets were morphologically well preserved, and parameters of cell viability and functionality such as DNA content and DNA synthesis, insulin content and stimulated insulin release were not different between the encapsulated and non-encapsulated control islets. A lower insulin secretion into the medium of the encapsulated islets during the first 3 weeks of culture can probably be explained by the capsule diameter (4-5 mm) and should be improved using microcapsules with a diameter of less than 1 mm.