Pluripotent possibilities

The Philadelphia Inquirer, The New York Times, and the Telegraph of London, on Aug. 23, 24, and 25, respectively, reported a "new method," a "breakthrough," and a development "close to the Holy Grail" in stem-cell research.

The newness, the breakthrough, and the holiness have to do with ways of generating useful stem cells for medical research without destroying human embryos. The London story spoke of pluripotent possibilities of rejuvenated adult cells; the two American papers spoke of human blastomeres. I would need the cellular biology equivalent of my Retired Racing Greyhounds for Dummies primer to demystify the details, but one simple enough observation emerges: We err when we think it necessary to resort to dubious strategies to obtain certain desired ends. Sometimes rescue is just around the corner, and a little patience might have spared the conscience.

I give you Abraham and Sarah, weary of waiting for the Lord's promised seed and taking matters into their own hands to secure an heir. The Pandora's box produced by that lapse from rectitude reverberates down the centuries, and in a little while God would bring Isaac anyway. King Saul, weary of waiting the full seven days for Samuel to offer sacrifice before the battle, takes matters into his own hands, just in time to see the prophet round the corner. Makes you think it's best to do things God's way-that He comes through in the end, and that some principles are more worth fighting for than a cure for Parkinson's.

Researchers salivate over those little chemical factories called embryonic stem cells (ESC) because of their ability to replicate indefinitely and to develop into any of the 200 types of tissues that make you you (that's pluripotency). But lately adult stem cells, which are found in the blood, tissues, and bone marrow of humans and can be extracted without harm to human life, are surprising everyone.

Until recently these oldsters were thought incapable of generating any but cells after their own kind. It turns out umbilical-cord blood contains not only the progenitors of blood and immune cells, but one-tenth of these stem cells can somehow create brain, liver, and heart cells. These cells have been used successfully to treat over 67 diseases.

In other laboratories, scientists are tricking adult stem cells into behaving more like embryonic ones. Human fat cells (of which America has no dearth) are being coaxed into mimicking muscle cells, thus offering hope against heart, bladder, and gastrointestinal diseases. Scientists have found that when they produce four proteins in skin cells from a mouse's tail, they can make the cells embryo-like. Professor Shinya Yamanaka of Kyoto University, a pioneer in this felicitous trickery, calls it "an important step toward converting adult cells into those that can grow into many different types." Promoting Senate bill 2754 which he co-authored with Sen. Arlen Specter, Pennsylvania Sen. Rick Santorum says, "The scientific advances of recent years have made it more and more likely that scientists do not need to destroy an embryo to obtain pluripotent cells."

Would that all the breakthroughs of August were so easy to case. Many researchers remain devoted to working the ethical bugs out of embryonic stem-cell study. One company, Advanced Cell Technology, has found a way to establish colonies of human ESCs from a human embryo without killing it. Till now, ESCs have been harvested from embryos consisting of about 150 cells (blastocysts), and the operation has always resulted in the death of the embryo. The biotech firm's new technique is to get the embryo at the 2-day-old stage, when the fertilized egg has divided into only eight cells (blastomeres). One of the eight can be removed for use, and the other seven implanted in the woman with no deleterious consequence. Lickety-split.

Or maybe not. Some embryos do not survive the procedure, and the long-term effect on the survivors is unknown. Another objection: The single cell that is removed could conceivably become an embryo itself. (And the creation of the little embryo by in vitro fertilization is ethically troubling to some.) White House spokeswoman Emily Lawrimore's initial reaction to the new procedure is that "any use of human embryos for research purposes raises serious ethical questions."

The Holy Grail remains elusive. The challenge to humanity still stands: to trust in the Lord of the breakthrough, while resisting the sirens of expediency.