title: Microencapsulated cells as hormone delivery systems.
abstract: Transplantation of pancreatic islets of Langerhans has been shown to prevent the development of many of the complications associated with diabetes. Transplanted islets, however, are readily rejected by the immune system. The use of artificial membranes to isolate the transplanted islets from the immune system of the host prolongs islet allografts in experimental animals. We have developed a method for encapsulating islets in semipermeable membranes composed of alginate and polylysine. The same technique can be applied to other endocrine cell types. The capsules are 700 to 800 micron in diameter with a hydrogel membrane approximately 4 micron thick. Intraperitoneal allografts of 5 x 10(3) encapsulated islets reversed diabetes in rats for up to 21 months and intact capsules with viable beta cells could be recovered from the recipients. Microencapsulation of endocrine cells for transplantation could potentially be used in the clinical treatment of hormone deficiency diseases.
authors.affiliation: Department of Physiology, University of Toronto, Ontario, Canada.
authors.forename: A M
authors.initials: AM
authors.lastname: Sun
authors.forename: M F
authors.initials: MF
authors.lastname: Goosen
authors.forename: G
authors.initials: G
authors.lastname: O'Shea
mesh_terms: D000818:Animals; D002214:Capsules; D002465:Cell Movement; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004337:Drug Carriers; D007328:Insulin / Q000008:administration & dosage*; D007332:Insulin Infusion Systems; D007515:Islets of Langerhans / Q000166:cytology*
chemical_list: D002214:Capsules; D004337:Drug Carriers; D007328:Insulin