By Dave Andrusko
Editor’s note. My family is on vacation. While we are gone I’ll be running articles from the past 12 months that you’ve indicated you particularly enjoyed. Dave
“The new direct-conversion approach avoids embryonic stem cells and the whole notion of returning to an early state. Why not just go directly from one specialized cell to another? It’s like flying direct rather than scheduling a stopover.’
— From “Scientists trick cells into switching identities,” by Malcolm Ritter of the Associated Press.
If you read Wesley Smith’s blog entry in Part One , you know that there is potentially an incredible twist in the ferocious debate over whether there really is an acceptable alternative to harvesting stem cells from human embryos. (Forget for a moment that there’s been no progress in humans whatsoever from ESCR–embryonic stem cell research. The onus always is on anyone who stands in the way of “progress” which just so happens to require the further debasement of the sanctity of human life to show they have another way.)
The analysis of the AP’s Malcolm Ritter, which ran yesterday in newspapers all over the country, not only says yes, but heck, yes. His first three sentences neatly summarizes what follows:
“Suppose you could repair tissue damaged by a heart attack by magically turning other cells into heart muscle, so the organ could pump effectively again. Scientists aren’t quite ready to do that. But they are reporting early success at transforming one kind of specialized cell directly into another kind, a feat of biological alchemy that doctors may one day perform inside a patient’s body.”
In explaining the new research Ritter casually comments that it is “two steps beyond the familiar story of embryonic stem cells…” That “story” (really a fairy tale) fanaticizes about embryonic stem cells being coaxed into becoming all type of cells, such as blood and brain cells. But Ritter notes in a huge understatement that “Using embryonic stem cells is proving to be inefficient and more difficult than expected.”
The new technique, if successful, is also a step beyond so-called induced pluripotent stem cells–iPSCs–which is ethically acceptable because it does not cause the destruction of a human embryo. As Ritter points out in 2007, “They got skin cells to revert to a state resembling embryonic stem cells [iPSCs]. That opened the door to a two-part strategy: turn skin cells from a patient back into stem cells, and then run the clock forward again to get whatever specialized cell you want. ”
But what does this “direct-conversion” approach (for example, turning human skin cells into blood cells) accomplish? It avoids the use of embryonic stem cells altogether, on the one hand, “and the whole notion of returning to an early state,” on the other hand.
Ritter asks, “Why not just go directly from one specialized cell to another? It’s like flying direct rather than scheduling a stopover.”
(The more-than-you-or-I need-to-know-but-is-interesting way to explain how all this is done can be summarized in three sentences. We know from our high school biology that every cell in our body carries the same DNA code. However a cell’s identity depends on “its lineup of active genes”–in other words not all genes are active at the same time. “So, to convert a cell, scientists alter that combination by inserting chemical signals to activate particular genes,” Ritter writes.)
This is all in the experimental stage, but the promise is extraordinary. “I think everyone believes this is really the future of so-called stem-cell biology,” John Gearhart of the University of Pennsylvania, one of many researchers pursuing this approach, told Ritter.