Stem Cell Breakthrough in Mice Points Toward a Way to Repair Tissue in Humans

The field of regenerative medicine hopes one day to be able to produce new, healthy tissues and organs with patients’ own DNA by turning some of the patient’s cells into stem cells that can then be guided to develop into healthy tissue.
 
The cutting-edge process requires doctors to remove some of a patient’s cells to do work on them in the lab.
 
But some Spanish researchers recently managed to turn mature cells into stem cells inside the body. They prompted the cells of adult mice to regain the ability to develop into any type of specialized cell, which is normally only briefly present during embryonic development. The results were published in September in the journal Nature.
 
The scientists likened the results to turning back the clock on dysfunctional human cells, giving them the chance to form again, erasing disease or other damage done over a lifetime.
 
“This change of direction in development has never been observed in nature,” said María Abad, the article’s lead author and a researcher in Manuel Serrano’s lab at the CNIO, as the center is known.
 
The experiment worked like this: Mice were genetically engineered to produce the genes that convert mature cells into stem cells. The transformation has previously only been successfully done in a Petri dish. When the genes were activated, the mice grew teratomas, or tumors made up of various tissue types akin to a failed embryo. The mice also began to circulate stem cells in their blood stream that were more diverse and plastic than even induced pluripotent stem cells, or iPSs.