Ethical Stem Cells?

A biotech company has described a method for growing stem cells without destroying embryos.

In a process that could offer a strategy for overcoming many of the ethical concerns over the use of embryonic stem cells, researchers at Advanced Cell Technology have created a line of such cells from a single human embryonic cell. Unlike existing methods, the procedure leaves the embryo viable, raising the possibility it could be widely used to create embryonic cells without destroying embryos. The work is described in this week's Nature journal.

Robert Lanza and his team at Advanced Cell Technology (ACT), a biotech company based in Alameda, CA, adapted a technique used by in vitro fertilization (IVF) clinics to perform genetic screening. The technique enabled the ACT team to extract a single cell from an embryo and to preserve its viability. The experiments resulted in the creation of two new lines of embryonic stem cells.

Embryonic stem cells, which can develop into any type of cell in the human body -- and thus have vast research and medical potential -- are usually grown from a mass of cells harvested from the embryo; the procedure destroys the embryo. In 2001, President Bush limited federal funding, including from the National Institutes of Health, to research on a small set of embryonic stem cell lines that already existed. As a result, the number of cell lines available to researchers who receive federal funding are few and of limited robustness.

Last December, Lanza and his coworkers published results reporting on mouse embryonic stem cells grown from a single cell. The new work applies the technique to grow human embryonic stem cells, Lanza says, and should end the ethical dilemma of needing to destroy embryos to create stem cells.

"There is now no rational ethical argument against stem cell research, now that we can preserve the embryo," he says. "The existing cell lines are weak, they're old, there are too few of them, and they are difficult to maintain. What we wanted to do with this process was to ensure that there are enough lines available. This should give the entire field a boost."