An Update on Induced Pluripotent Stem Cells
The research community is steaming ahead with a promising methodology for producing the building blocks of all tissue types directly from your own cells:
researchers used genetic alteration to turn back the clock on human skin cells and create cells that are nearly identical to human embryonic stem cells, which have the ability to become every cell type found in the human body. Four regulator genes were used to create the cells, called induced pluripotent stem cells or iPS cells....
Reprogramming adult stem cells into embryonic stem cells could generate a potentially limitless source of immune-compatible cells for tissue engineering and transplantation medicine. A patient’s skin cells, for example, could be reprogrammed into embryonic stem cells. Those embryonic stem cells could then be prodded into becoming various cells types - beta islet cells to treat diabetes, hematopoetic cells to create a new blood supply for a leukemia patient, motor neuron cells to treat Parkinson’s disease.
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Our reprogrammed human skin cells were virtually indistinguishable from human embryonic stem cells. Our findings are an important step towards manipulating differentiated human cells to generate an unlimited supply of patient specific pluripotent stem cells. We are very excited about the potential implications.
Infrastructure is important: any advance that lowers the cost of a common tool or resource will speed progress. The new news in this latest press is that the procedure has been reproduced fairly rapidly by different research groups. It is therefore probably viable as a technology base for regenerative medicine, organ regrowth, drug testing, research into the biomechanisms of disease, and everything else you'd want a cheap supply of pluripotent stem cells to achieve.
Great news, but I have this question: what possible reason or mechanism exists for assuming that an "induced" stem cell created from an already aged cell wouldn't get some of the induced damage carried along with the machinery? I can't see how this would be a 100% "reset".
Still, I imagine even a slightly pre-aged replacement organ from your own cells would be a helluva a lot better than a foreign transplant with rejection problems.
Here's another one -- if you're replacing an organ or tissue because of genetic disease, how long before the newly constructed replacement would start to fail in the same way? If triggers elsewhere in the body ar eimportnat, then it might happen sooner than later. OTOH if it would take another 50 years to start falling apart, that's surely good enough.
Yet I don't see either of these addressed in popular accounts, even speculative ones. I read about cancer questions, but not these.
I really hope they have found a way to reverse the majority of the damage. The main concern when it comes to turning back the clock on our own cells is to verify that it is undamaged. This is especially problematic since in the long run, more and more (all?) cells accumulate some damage, so you'll have inconsistant deviations from a healthy archtype.
This is probably why a lot of people want to preserve their DNA early so that source can be copied, rather than the one all wartorn from living life and undergoing continual metabolism.
I would guess the best preserved cells would be those from which sex cells are created since they more than other somatic cells must avoid mutations most to avoid passing them on to future generations. We should take from there.