Canine Islet Isolation, Cryopreservation, and Transplantation to Nude Mice.

Background: Successful human islet transplantation has led to insulin independence intype 1 diabetes. Dogs constitute an animal model for preclinical studies. Wepresent our recent experience in canine islet isolation, cryopreservation andtransplantation.Methods: Twenty-seven pancreases from mongrel dogs, weighing 9-31 kg, wereremoved. Each pancreas was digested with collagenase, and then purified bydensity gradients. Islet number and purity were counted, and the viability ofisolated islets was assessed in vitro by static incubation, perifusion study andin vivo transplantation into nondiabetic or diabetic nude mice. Additionally,freshly isolated islets were cryopreserved for 1 week, and then studied invitro.Results: The islet yield and purity were 121,000