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I think the promise of cell replacement for PD – depends on who you are reading…. Science aside, opinions on cell replacement therapy (and future research funding) may be influenced by the wording of the the trial results. One can look at tissue transplants as a “failure” because after 14-16 years there was evidence of cell damage or as a “success “ because there was also evidence that transplanted neurons survived for up to 14 years and trial participants did “ experience some long time relief of their PD symptoms.” Questioons to ask -- What is highlighted in the articles – the pathology or the relief of symptoms, even if limited ? Whose opinions are we reading? Are there any possible conflicts of interest noted by the researchers? who should receive the limited funding? For example Published in April 2008 Nature Medicine were a series of communications on the Lewy body-like pathology found in the brains of some fetal tissue transplant trial participants. Written by Jeffrey H Kordower, Yaping Chu, Robert A Hauser, Thomas B Freeman & C Warren Olanow Title: “Lewy body–like pathology in long-term embryonic nigral transplants in Parkinson’s disease" In the same issue of Nature medicine, Dr. Ole Isacson, and his team report that "Dopamine neurons implanted into people with Parkinson’s disease survive without pathology for 14 years." (Title) Another letter by Olle Lindval et al stated “,,available data suggest that the majority of grafted cells are functionally unimpaired after a decade, and recipients can still experience long-term symptomatic relief.” Another report by Isacson’s team from Aug 2009 Journal of Neurology: . 2009 Aug;256 Suppl 3:310-6. Title: Lack of functional relevance of isolated cell damage in transplants of Parkinson's disease patients. Cooper O, Astradsson A, Hallett P, Robertson H, Mendez I, Isacson O. “Abstract :Postmortem analyses from clinical neural transplantation trials of several subjects with Parkinson's disease revealed surviving grafted dopaminergic neurons after more than a decade. A subset of these subjects displayed isolated dopaminergic neurons within the grafts that contained Lewy body-like structures. In this review, we discuss why this isolated cell damage is unlikely to affect the overall graft function and how we can use these observations to help us to understand age-related neurodegeneration and refine our future cell replacement therapies.” Even if not a cure 10 + years of symptomatic relief sounds darn good to me More questions--What do the trial results mean to real patients? Is the glass half empty or half full? Linda www.pdpipeline.org ---------- Original Message ---------- From: Mary Ann Ryan <[log in to unmask]> To: [log in to unmask] Subject: Re: DOPAMINERGIC TRANSPLANTS FAIL IN PARKINSON'S DISEASE Date: Fri, 27 Nov 2009 09:09:23 -0500 Wow! This is not good news. Everyone thought that cell based therapies were going to be the answer to PD. I'm speechless. --------- Mary Ann www.bentwillowfarm.org > For years, cell-based therapies that involve the transplantation of > dopaminergic cells in to the brain have attracted considerable interest as > possible treatments for Parkinson's Disease. However, all of the > double-blind, > sham-controlled, studies have failed to meet their hoped for efficacy. > Transplantation of dopamine cells derived from the fetal mesencephalon is > also > associated with a potentially disabling form of dyskinesia that persists > even > after withdrawal of L-dopa. In addition, disability in advanced patients > primarily results from features that are not primarily due to insufficient > dopamine. These features are not adequately controlled with dopaminergic > therapies and are thus unable to respond to dopaminergic transplants. > Implanted dopaminergic neurons have also recently been found to contain > Lewy > bodies, which are signs of cell damage, suggesting that even after > transplantation they are dysfunctional and may have been affected by the > Parkinson's Disease process. Although stem cell therapies have been tried > in > Parkinson's Disease based on the claim that there is a massive loss of > dopamine producing cells in Parkinson's Disease, not a single study has > ever > shown this to be true. > > > viartis.net > > > ---------------------------------------------------------------------- > To sign-off Parkinsn send a message to: > mailto:[log in to unmask] > In the body of the message put: signoff parkinsn ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn