The proposed research seeks to establish the feasibility of a macroencapsulation device containing islet cells for the treatment of insulin dependent diabetes. The device is a direct application of the spinal fluid flow driven artificial organ invented by the P.I. (U.S. Patent No. 5,222,982). Preliminary experiments in vitro and in vivo (canine model) indicate that xenograft islet cells are immune protected while living in CSF, CSF glucose follows serum glucose, islets in CSF release insulin with lag times less than 25 minutes and diabetic dogs display decrease of serum glucose and insulin requirements under short- term observation. These data are presented in the body of our proposal. We seek to extend and complete these observations for longer periods of treatment with larger numbers of islets and confirm the immune protection including the lack of significant host sensitization to proteins associated with the xenogenic islets. The work will be carried on as before using a CRADA with Dr. Illani Atwater at NIDDK/NIH and with Dr. J. Bacher at NCRR/NIH.