{"id":155469,"date":"2010-01-08T16:57:55","date_gmt":"2010-01-08T21:57:55","guid":{"rendered":"http:\/\/www.diabetesforums.com\/forum\/type-1-diabetes\/47401-pancreatic-islet-grafts-cure.html"},"modified":"2010-01-08T16:57:55","modified_gmt":"2010-01-08T21:57:55","slug":"pancreatic-and-islet-grafts-and-the-cure","status":"publish","type":"post","link":"https:\/\/mereja.media\/index\/155469","title":{"rendered":"Pancreatic and Islet Grafts and the Cure"},"content":{"rendered":"
Any purported cure for type 1 diabetes which involves transplanting tissue so that it is in contact with the body’s immune system is irrational, since the graft can only be protected by extremely toxic immunosuppressive drugs, whose side-effects are more damaging than uncontrolled diabetes itself. Not only do these drugs cause heart disease, atherosclerosis, osteoporosis, neuropathy, infection risk, and a quadrupling in the risk of death by cancer, but they also cause diabetes in many patients. There is no sense in replacing diabetes due to autoimmunity by diabetes due to immunosuppressive drug toxicity, at the cost of all the other risks of those drugs plus an elaborate operation. This is why pancreatic or islet transplant is now usually offered only to diabetics who require a kidney transplant and toxic immunosuppression anyway.<\/p>\n

Not only does pancreatic and islet transplant face the normal problem of rejection by the body’s reaction to foreign tissue, but it would also be confronted by the persisting autoimmune attack on pancreatic beta cells by the antibodies which caused the diabetes in the first place.<\/p>\n

A further problem is that the amount of human pancreatic or islet tissue available for transplant is extremely small. The waiting list for various human organs for transplant is growing much faster the the organs available for transplant, which have remained stagnant since the 1990s, and patients in the U.S. can wait for seven or eight years for a new organ. The shortage would be extremely serious for pancreatic transplants, since while there are only about 400,000 people in need of a new kidney, there would be about 1.5 million people in line for a new pancreas. Islet transplants do little to solve the problem, since it usually requires tissue from two pancreases to harvest enough islets for one patient. Some have estimated that if pancreatic and islet transplants were made available to all type 1 diabetics, the supply of cadaver source organs would suffice to treat only about 1% of those needing a transplant. Animal tissue grafts could never be used to make up the shortfall, since any animal tissue in direct contact with the human immune system would be destroyed in a few hours by the process of hyperacute rejection. When the first kidney transplants were attempted at the University of Strassbourg in 1905, a pig’s kidney was attached to a cut-down vein and artery in the patient’s arm, and it withered away in just a few hours.<\/p>\n

Because of unknown causes which have been labeled simply ‘chronic allograft disease,’ transplanted tissue never lasts as long as normal tissue, even apart from problems with rejection by the immune system. Even if a pancreatic or islet transplant is undertaken, it will only function for a few years, and it would be rare for such a graft to last more than a decade. Future transplants would be more likely to be rejected by the immune system, since antibodies to foreign pancreatic tissue would be formed by the first transplant, which would then already be lying in wait to destroy any new tissue of the same organ type.<\/p>\n

The transplantation of a new pancreas is difficult since it is surgically extremely difficult to position it in the locus of the natural pancreas. Instead it is positioned elsewhere in the abdomen, and the digestive fluids it produces have to be artifically ciphoned off directly into the bladder, which sometimes results in further metabolic abnormalities. Overall, pancreatic transplant has more complications than the typical kidney, liver, or heart transplant.<\/p>\n

Interestingly, pancreatic transplantation is much less helpful in prevening diabetic complications than would be predicted by the predominant theory that blood sugar abnomalities cause the complications of diabetes. In one survey of the results of a large number of pancreatic transplants, the recipients’ retinopathy was found to improve clearly in 8.8% of patients, but it seriously worsened post-transplant in 17.1% Overall, the retinopathy became worse in 46% of all patients following their pancreas transplant, while it stabilized in 54%. In another study no improvement in cardiac disease, no improvement in severe retinopathy, and no improvement in diabetic neuropathy was found after pancreatic transplant.<\/p>\n

Sources: A. Koenigsrainer, et al, "Does Pancreas Transplantation Influence the Course of Diabetic Retinopathy?" DIABETOLOGIA, vol. 34, no. 1, p. 586 (1991); J. de Sa, et al, "The Evolution of Diabetic Chronic Complications After Pancreas Transplantation," DIABETOLOGY AND METABOLIC SYNDROME, vol. 1, no. 1, p. 11 (2009).<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

Any purported cure for type 1 diabetes which involves transplanting tissue so that it is in contact with the body’s immune system is irrational, since the graft can only be protected by extremely toxic immunosuppressive drugs, whose side-effects are more damaging than uncontrolled diabetes itself. Not only do these drugs cause heart disease, atherosclerosis, osteoporosis, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-155469","post","type-post","status-publish","format-standard","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts\/155469","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/comments?post=155469"}],"version-history":[{"count":0,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts\/155469\/revisions"}],"wp:attachment":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/media?parent=155469"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/categories?post=155469"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/tags?post=155469"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}