The loose adaptive structure of a stem cell, above. Differentiated cell below. Image from http://learn.genetics.utah.edu/content/
What is the difference between a stem cell that could re-build a sick or damaged body and a specialized, mature cell? Four genes.
A number of cells shut off once a cell specializes. When researchers introduce them into an unsuspecting skin or fat cell it can be re-programmed into a stem cell. Essentially, the treatment unlocks the genes that shut down after determination. This process was discovered in 2012 and it creates induced Pluripotent Stem cells, or iPS cells for short.
iPS cells may be the best type to use in therapies. Creating them does not destroy embroyos and since they started out as the donor’s own cells they can theoretically be given back to the donor without an immune system disaster, so what holds researchers back?
Deadly errors. Re-programming a cell could change the genes. What if we introduce an unintended change?
There isn’t a perfect type of stem cell to use in therapies yet, but if there was one, how close would we come to eliminating disease?
For the novel I’m writing, I need a stem cell that can form inside the human body and bring characters back from injury and death. iPS cells are a good fit because a fictional gene might be able to reprogram cells near an injury or reduce damage due to aging.
But there is one type of stem cell, an elusive and possibly non-existant option that might work even better. I’ll talk about it next week.
Sources:
Reversing Cell Differentiation
http://learn.genetics.utah.edu/content/stemcells/ips/
Stem Cell Quick Reference
The Phoenix Series 