A team of researchers in the US has created human embryonic stem cell (hESC) lines without destroying the embryos in the process. They hope these findings will change the legislation limiting federal funding for hESC research in the US.
The scientists at Advanced Cell Technology (ACT), in Massachusetts, reported in the journal Cell Stem Cell that they have grown five new robust hESC lines by plucking single cells, 'blastomeres', from the embryo at the early blastocyst stage. This technique mimics 'PGD', a process routinely used by IVF doctors to screen embryos for genetic disorders before implanting them in the uterus.
The work builds on findings reported in August 2006, when Lanza demonstrated 'proof of principle' for the technique. In the latest study, Lanza showed that the embryos survived to the 10-cell stage 80 per cent of the time, the same rate as IVF embryo survival, and that the embryos can be frozen for potential future IVF use. Current hESC technology involves plucking cells at a later developmental stage from the entire mass of embryonic cells, which results in the destruction of the embryo. The work has also been replicated by Olga Genbacev's team at the University of California at San Fransisco.
The political effect of this achievement could potentially be extremely significant. The Bush Administration limited hESC research funded by federal grants in the US in 2001, citing ethical issues raised by the destruction of embryos in the process, which has hampered rapid progression of research. This issue, however, is avoided by the new technique, and scientists hope pressure will be put on the Bush Administration to lift the heavy restrictions.
Privately funded research schemes using hESCs, such as ACT, have no such restrictions.
The main consequence of the study is that many more hESC lines could now be produced for critical research into many diseases which are causing needless deaths. 'We could double or triple the number of hESC lines available within a few months', says Lanza, who has already approached the White House about endorsing the technique, 'I hope the President will act now and approve these hESC lines quickly'.
There is still likely to be some opposition to this research, for example from religious activists who claim that the work is still exploiting and potentially harming the embryos despite their survival.