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In an unexpected setback to efforts to harness a promising new type of stem cell to treat diseases, researchers reported on Friday that tissues made from those stem cells might be rejected by a patient’s immune system — even though the tissues would be derived from the same patient.

The research involved so-called induced pluripotent stem cells, or iPS cells, which can be made from skin cells and which appear to have the characteristics of embryonic stem cells. That means they can theoretically be turned into nerve, heart, liver or other types of cells and transplanted to repair damaged organs.

The initial creation of human iPS cells in 2007 electrified scientists because the cells seemed to have two big advantages over embryonic stem cells. They were not controversial, because their creation did not entail the destruction of human embryos. And since the stem cells could be made from a particular patient’s skin cells, they could be used to make tissues that presumably would not be rejected by that patient’s immune system.

But that latter assumption was never really tested, until...