If iPSCs work, they will be better than ESCs because they will be made from the patient’s own cells, and hence, no tissue rejection. They will also be better than using cloned ES cells because they will be easier and less expensive to derive. They will be better than both therapeutic cloning and ESCR because they will be ethically unproblematic. Thus, it is very good news that in mice, iPSCs are proving useful in heart repair. From the story:
Ordinary cells reprogrammed to act like embryonic stem cells can help repair damaged heart tissue in mice, researchers reported on Monday in a study that shows a potential practical use for the experimental cells. When injected into mice whose hearts had been damaged by a heart attack, the new cells helped improve both the structure and function of the heart. Eventually the hope would be to patch up seriously ill heart patients using their own cells. “It was obvious to the observer which animals had been treated and which ones hadn’t,” said Dr Timothy Nelson of the Mayo Clinic in Rochester, Minnesota, whose study appears in the journal Circulation...
Instead of coaxing the iPS cells into a specific type of heart tissue, they used the iPS cells in their most embryonic-like state. Nelson said two weeks after they had transplanted the cells, they started making different types of heart tissue, including heart muscle, blood vessels and the cells that line blood vessels. “They were able to respond to this damaged environment and spontaneously give rise to the appropriate tissues and create new tissues within that diseased heart,” he said. “That is a key wow factor of this paper.” Nelson said heart cells continued to grow for four weeks, and the mice that got the iPS cells got better. Both the structure and the function of their hearts improved compared to animals injected with cells that form scar tissue, he said.
This doesn’t cure the tumor problem associated with all pluripotent stem cells—whether ESCs or iPSCs—of course. But ethical research is sure transforming the field.