From the UK's Sunday Times:
I'm not surprised that Pfizer is interested in the therapy. Recipients will be required to take Pfizer's anti-rejection drugs the rest of their life if embryonic stem cells are used.
We have several areas of our bodies that the immune system appears to be incapable of function. These are called immune-privileged sites, and include the eye, brain, ovary and testis.
You can read more about it here.
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