Type 1 diabetes mellitus is one of the commonly diagnosed endocrinopathies in dogs. Exogenous insulin administration addresses clinical signs, but when normal glucose homeostasis is not restored, complications (eg, cataract formation, pancreatitis, diabetic ketoacidosis) can persist. Pancreatic islet transplantation in humans restores glucose homeostasis, reducing risks for complications. Islet yield in human pancreatic islet transplants improved with use of a temperature-controlled perfusion circuit, enzymatic digestion, and Ricordi chamber for mechanical agitation. This is the standard method for humans and is examined in this study on deceased canine donors to evaluate islet yield and purity.
Initial anatomic studies demonstrated that infusion via cannulation of both the accessory pancreatic duct and distal right limb of the pancreas enabled complete perfusion of the pancreas. Islet isolation was then performed in 6 dogs, and yield and viability were calculated using dual fluorescent staining techniques. A high degree of islet purity (endocrine tissue, 87.5%) and viability (87.4%) were achieved. Islet yield using this technique required about 1 pancreas per 5 kg body weight of recipient dog. Purity and viability levels were comparable with those seen in human pancreatic islet isolation.
According to this study, it is clinically feasible to obtain acceptable islet yield and quality from deceased canine patients using standard laboratory equipment. Further studies are needed to evaluate new isolation techniques, implantation sites, immunoisolation, and immunotherapeutic strategies.