Brain cells from stem cells

Can we please have sensible science policy in the US before it is too late? Why are we allowing the UK and S. Korea to race ahead in this important area of research? (See previous post on therapeutic cloning by Seoul National University researchers.)

Guardian: British scientists create first pure brain stem cells

Scientists have made the world's first pure batch of brain stem cells from human stem cells. The breakthrough is important in the fight against neuro-degenerative diseases such as Alzheimer's and Parkinson's and could also reduce the number of animals used in medical research.
Stem cells can change into any type of cell in the body. How they change, a process known as differentiation, remains a mystery but scientists think certain chemical and environmental signals must trigger it.

Austin Smith of Edinburgh University's institute for stem cell research bathed stem cells taken from mouse embryos with two proteins called epidermal growth factor and fibroblast growth factor, both of which are known to be involved in the normal development of the embryonic brain. After his team had shown the process turned embryonic mouse stem cells into brain stem cells, they repeated the experiment on human embryonic stem cells.

Brain stem cells have been grown before but the results have been impure. "You end up with a mixed culture at the end which has not just neural stem cells, it has a lot of contaminating embryonic stem cells," said Steve Pollard, one of Professor Smith's colleagues and a co-author of the results, published yesterday in the journal PLoS Biology.

The work comes three months after scientists at Newcastle University cloned a human embryo using donated eggs and genetic material from stem cells. Human embryos were first cloned last year by South Korean scientists.

In the short term, the technique will allow scientists to develop cell cultures for their research. "We'll use them in the basic biology sense to try to understand how stem cells work," Professor Pollard said. "It's a good opportunity to understand what the difference is between an embryonic stem cell, which can make anything, and a brain stem cell, which can just make brain."

Through genetic modification, scientists will also use the technique to mimic brain diseases.

Tim Allsopp, the chief scientific officer of Stem Cell Science, the company given an exclusive licence to commercialise the research, said: "The remarkable stability and purity of the cells is something unique in the field of tissue stem cells and a great step forward. We have already had a number of approaches from pharmaceutical companies interested in using these cells to test and develop new drugs, and are looking forward to working with them to further develop and license the technology."

In the longer term the technology raises hopes of growing cells to replace damaged parts of the brain. But Professor Smith said there was a long way to go: "We know these cells can survive if we put them back in the brain but whether they can do anything useful is a much more complicated question."