Stem Cell Solution

Back in 2001, when President Bush decided to limit federally supported embryonic stem cell research to cell lines that had already been created, government officials said there were at least 60 lines available for researchers to work on. This month the National Institutes of Health announced there were just 11. Bush should reconsider his 2001 decision and permit US funding for work on more stem cell lines, which would be donated by couples who have decided they won't be using them in their fertility treatments. Scientists believe that embryonic stem cells hold great promise for treating diseases like diabetes and Parkinson's because of their ability to replace defective human cells. The work is still at the basic stage, however, and is thus dependent on government grants. It is crucial, therefore, that the president ease his restrictions. The work is controversial because getting stem cells from embryos destroys them, which some equate with abortion. Not only are there just 11 lines available, offering limited genetic diversity, but all have been developed in the presence of mouse ''feeder'' cells, which provide growth factors. This disqualifies them for human therapeutic experiments because of the danger of contamination by mouse viruses or proteins. Since 2001, scientists have learned how to develop stem cell lines without help from mice.

There are more than enough excess embryos for researchers' needs. A recent survey found there were 396,526 embryos in storage, reflecting the common practice of extracting more eggs from women than are needed. Already, couples have declared 11,000 of these embryos available for research.

A US model for a repository and registry of an adequate stem cell supply is a proposed stem cell bank in England, where government-backed scientists will not be limited to pre-2001 cell lines. As outlined by six scientists in the current issue of Science, a US repository would collect and test a range of stem cell lines, including ones developed since 2001 without mouse feeder cells. The repository could provide stem cell lines to academic institutions, sparing them the difficulties of dealing separately with universities, institutes, and other owners of the lines. The repository's registry could maintain a database of information about the stem cells.

But the indispensable step for successful American research would be a decision by the Bush administration to expand the number of stem cell lines eligible for federal support. Without such a policy change, progress in fighting diseases will be slowed, and American cell biologists could seek greener pastures in the United Kingdom.