|
|
Stem cells—the versatile cells that, on demand, can become other cells to make up muscle tissue or bone or an organ—aren’t all the same.
“Multipotent” stem cells are common in the body’s tissues and can become different kinds of cells within the body part where they’re found.
“Pluripotent” stem cells are the ones in embryos that can transform themselves into cells for almost any body part. A few years ago, scientists discovered how to turn plain adult cells back into pluripotent cells to create new forms of treatment for a range of illnesses and chronic conditions.
“Totipotent” stem cells are the most powerful: the single cell created by the union of sperm and egg is totipotent, meaning all other cells, including stem cells, arise from it.
Now scientists at China’s Tsinghua University have discovered a combination of three molecules that can turn adult cells into totipotent ones.
This has never been done before and could mean that organisms could be created from a single cell without fertilization or the messy and risky process of cloning.
Two of the molecules, called 1-Azakenpaullone and WS6, stimulate the growth of cells and protect them from harm. Another, known as TTNPB, fosters cell reprogramming.
The Chinese researchers used artificial intelligence to screen thousands of combinations of molecules known to be effective in reprogramming adult cells.
When they had their three-molecule candidate cocktail, they tested it in petri dishes and in living mouse embryos.
In all cases, cells in petri dishes dosed with the cocktail became totipotent, turning on hundreds of genes the way that totipotent stem cells normally do. In live embryos, the treated cells differentiated into the normal specializations needed to create new mice.
TRENDPOST: Theoretically, this breakthrough could easily enable infertile adults to have children that are biologically their own or allow biologists to repopulate endangered species.
As usual, however, the ethical questions will take longer to resolve than the technical ones.