Chick embryo pancreatic transplants reverse experimental diabetes of rats.

Abstract

A B S T R A C T The effectiveness of xenogeneic embryonic tissue in the treatment of experimental diabetes has been investigated in rats. The splenic lobes (80) of 15-to 18d-old chick embryos, composed almost exclusively of endocrine tissue, were implanted directly into the hepatic parenchyma of the rat recipient. The biochemical and metabolic changes in the recipients suggest that embryonic transplants of 15-d-old chick pancreases were able to significantly improve, for a prolonged period of time (18 mo), the diabetic state of nonimmunosuppressed rats. None of the recipients of 18-d-old embryos splenic lobes exhibited a long-term improvement ofthe diabetic state after transplantation. The complete destruction of the pancreatic B cells of the recipients was asssessed by: (a) immunocytochemical investigations of the recipient's pancreas, (b) measurement of insulin in the liver and pancreas of the recipients and (c) in situ vascular perfusion of their pancreas submitted to high glucose challenge. The results suggest that pancreatic tissue of the 15-d-old embryos is immunologically immature lacking one or several lymphocyte subsets implicated in the afferent loop of "non-self" recognition.

Organogenetic tolerance

“…It is possible that xenotransplantation of fetal pancreas is particularly suited to induction of tolerance. However, neither Eloy et al 20 nor Abraham et al 21 nor we 3,10-13 define an immunological mechanism.…”

“…Eloy et al described normalization of glucose post-transplantation of E15, but not E18 embryonic chick pancreas into non-immmune suppressed STZ-diabetic immune competent rats. 20 Abraham et al 21 described successful xenoengraftment in multiple organs of human pancreatic islet-derived progenitor cells infused in non-immunosuppressed immune competent mice. It is possible that xenotransplantation of fetal pancreas is particularly suited to induction of tolerance.…”

Pancreas and islet transplantation

“…Eloy et al [253] found that islet rich, 15 day (but not 18 day) chick embryo pancreas significantly improved diabetes in rats after direct injection into the hepatic parenchyma. Except for this report, discordant xenografts have been successfully transplanted only under very special circumstances, to thymic aplastic mutant nude (nu/nu) mice or nude (rnu/rnu) rats, which are genetically unable to reject allo-and xenografts [254,255].…”

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“…1 Cell therapy has since grown rapidly by nonhomogenous cell therapy from chick embryo pancreatic transplant, which reversed experimental diabetes in rats. 2 Mario Capecchi, Martin Evans, and Oliver Smithies received the 2007 Nobel Prize in Physiology or Medicine for work going back to 1981 on development of mouse embryonic stem cell technology that allowed any gene to be "knocked out" in mice. 3 In 1998, Thomson and associates adapted the mouse techniques to human blastocysts, showing for the first time that human stem cells could be established.…”