As if the stem cell debate weren’t dramatic enough, an experiment has now documented for the first time that embryonic stem cells can be turned into CD4 cells. For HIV treatment, this would allow genetic-tinkering therapies to chuck the painful and sloooow (as in three hours or more) process of extracting positive people’s own stem cells to grow them into CD4 cells.

In some gene therapy trials, these -engineered CD4s are then returned to the body to suppress viral reproduction and produce other battle-worthy immune cells. Using embryonic cells instead of extracted adult cells would provide a consistent, accessible source, says Jerome Zack, PhD, a coauthor of the embryonic research at the University of California at Los Angeles. Zack adds that while the discovery is “a baby step, not ready for prime time,” it could mature into research options. “Adult stem cells are limited in what cells they can become,” he says, “while embryonic cells can develop into any cell type.”

Zack does worry that Bush’s stem cell veto will block the work. “Clearly,” he says, “research would move faster if more funding and access to [embryonic] stem cells were approved.” We vote yes.