By Todd Zwillich

WASHINGTON (Reuters Health) Jun 30 - National Institutes of Health researchers have transformed human embryonic stem cells into dopaminergic neurons.

"There has been some rather notable progress made," Dr. James Battey, chair of NIH's stem cell research task force, told members of an advisory panel to NIH director Dr. Elias Zerhouni.

It is still too early to tell whether the cells will be able to function normally if implanted into a patient's brain, Dr. Battey said in a later interview. But so far the cells "look great in the lab."

He told the panel that an NIH research team led by Dr. Ronald D. G. McKay used a 5-step process to transform human embryonic stem cells into cells that can produce dopamine and are able to fire action potentials.

"These are cells that resemble in every way a dopamine-producing mid-brain cell," said Dr. Battey, who also directs NIH's Institute of Deafness and Other Communication Disorders (NIDCD).

The researcher told NIH officials and advisors that the finding shows that basic research is moving forward under a controversial 2-year-old White House directive that limited federal funding for embryonic stem research. The decision, issued by President Bush in 2001, confined federal funding to embryonic stem cell lines that had already been derived by the time of the announcement.

"Many of the studies that are begging to be done can be done right now," Dr. Battey said

However, Dr. J. Michael Bishop, an advisory board member and Chancellor of the University of California at San Francisco, warned that the limits will keep scientists from working with immunologically diverse cells that will be needed for human implantation.

"We can't keep our head in the sand about the need to develop additional lines," he said. "I just don't want anyone to leave this room thinking that the difficulties...can be discounted."