A Step Toward Curing Parkinson's Disease and New Hope for Curing Many Other Degenerative Diseases of Ageing

Guardian
A research team at Sloan-Kettering have devised a range of methods for converting stem cells into specific differentiated cells. Their most recent triumph was the successful creation of dopamine producing cells from the substantia nigra -- the main part of the brain that degenerates in Parkinson's Disease.

Dr Studer and his colleagues, whose work is published in the journal Nature, found the specific chemical signals required to nudge stem cells into the right kind of dopamine-producing brain cells.

In a series of experiments, the team gave animals six injections of more than a million cells each, to parts of the brain affected by Parkinson's. The neurons survived, formed new connections and restored lost movement in mouse, rat and monkey models of the disease, with no sign of tumour development. The improvement in monkeys was crucial, as the rodent brains required fewer working neurons to overcome their symptoms. _Guardian

The finding brings researchers a step closer to testing a stem-cell-derived therapy in patients with this disorder. "We finally have a cell that seems to survive and function and a cell source that we can easily scale up," says Lorenz Studer, a researcher at the Sloan Kettering Institute and senior author on the new study. "That makes us optimistic that this could potentially be used in patients in the future."

The research also highlights the challenges of generating cells for tissue-replacement therapy, showing that subtle differences in the way the cells are made can have a huge impact on how well they work once implanted.

...While stem-cell researchers had previously been able to create dopamine-producing neurons from human stem cells, these cells did little to alleviate movement problems in animals engineered to mimic the symptoms of Parkinson's. In 2009, Studer and others developed a method of making the cells that more closely mimics the way they form during development. The resulting cells also carry more of the molecular markers that characterize dopamine-producing cells in the brain.

In the new research, published Sunday in the journal Nature, Studer's team found a way to make these cells even more efficiently. This is significant in terms of ultimately testing the therapy in humans; many methods for making specific types of cells are complex and yield small amounts of the desired product. _MIT TechnologyReview

This is a preliminary triumph for regenerative medicine, with every reason to expect that this development can move expeditiously from the animal lab into clinical research. The Sloan-Kettering team has made many improvements in the safe conversion of embryonic stem cells to mature differentiated cells, and have reduced the risk of tumour formation from these cells, when transplanted.

The ultimate goal is to be able to take donour cells from the patient himself, and turn those cells into young and vigorous cells of any cell type that is needed, in as large a number as needed -- even to the point of growing replacement organs from the person's own cells. Researchers are making progress in that area, but the pressing need to treat the growing number of ageing individuals with degenerative conditions may call for stop-gap measures such as the use of embryonic stem cell treatments described above.

Brian Wang has also looked at this story