14 cm bacteriological petri dishes at a cell density of approx 10 5 cells cm 2 the aggregates were implanted into immunodeficient nude mice that had been made diabetic by intravenous injection of 90 mg kg bodyweight of alloxan animals were anaesthetized with avertin and an incision was made in the dorso lateral skin at the level of the kidney the kidney was extruded and a small incision made in the kidney capsule an obdurator was inserted between the kidney capsule and the kidney parenchyma and the capsule was carefully detached from the underlying tissue the reaggregated porcine pancreatic cells were collected from their culture dish and brought into a small volume of hamf10 containing 5 decomplemented mouse serum after which they were taken up in sterile thin plastic tubing blocked at the end by two metal surgical clamps and subsequently centrifuged by hand for 2 u2032 at approximately 100 rpm immediately before implantation the tip of the tubing was cat and the pelleted material injected under the kidney capsule in the pocket prepared by the canulae the opening in the kidney capsule was sutured using an electric low temperature cautery device and the kidney replaced into the body cavity after which the incision was closed with sutures.