As another poster says, there was not ever a substantive "debate" with regard to ordinary stem cells, only ones derived from fetal tissues and discarded fertili

As another poster says, there was not ever a substantive "debate" with regard to ordinary stem cells, only ones derived from fetal tissues and discarded fertilized embryos from IVF. One of the things about the embryonic stem cell debate I always found maddening is that none of the proponents of using them had a solid answer to overcoming immune rejection problem. If you're going to make new organs from someone else's tissue, you have a lot of heavy lifting to do to make sure those things don't cause the recipient to attack the cells/tissues that you've transplanted. This is a massive problem with organ transplants generally, and I see no reason why stem cells wouldn't be in the same category (though I'd love to know if my knowledge is outdated/wrong). Even assuming that there are ways to get around the immune system (e.g. taking anti-rejection meds). It is likely far easier and safer to work with pluripotent cells from an adult who is also both the donor and recipient. Even if there's a genetic defect that needs to be "patched" prior to re-implantation, that is far easier than trying to make a foreign cell look like it's from you or being on meds for the rest of your life so your body doesn't attack that new liver.