The present invention relates to an in vitro method for preparing and producing canine pancreatic islets from immature pancreatic tissue. Such islets express, produce and secrete insulin upon glucose stimulation. The invention further encompasses canine pancreatic islets obtainable according to the present method, islet population of said islets and compositions comprising said islets. It also relates to transduced canine pancreatic islets, or tumours or cells derived thereof. The present invention also concerns the use of said canine pancreatic islets or cells derived thereof for treating a canine pancreatic disorder, such as canine diabetes, or for diagnosing canine diabetes.
