Animal to Human Xenotransplantation Takes a Big Leap Forward

Scientists in Japan have used animal research to explore a potential way around the organ shortage by growing transplantable organs in sheep made from stem cells. In this case, it is monkey organs, but within a decade, it could be human organs. From the story:

Huddled at the back of her shed, bleating under a magnificent winter coat and tearing cheerfully at a bale of hay, she is possibly the answer to Japan’s chronic national shortage of organ donors: a sheep with a revolutionary secret. Guided by one of the animal’s lab-coated creators, the visitor’s hand is led to the creature’s underbelly and towards a spot in the middle under eight inches of greasy wool. Lurking there is a spare pancreas.

This would not be xenotransplantation in the usual sense of the term, since the procured organ would not be the sheep’s own, but as I understand it, would be a construct made from human stem cells:

The organ growing on the sheep was generated from monkey stem cells but the man behind the science, Yutaka Hanazono, believes that the technology could be developed eventually to make sheep into walking organ banks for human livers, hearts, pancreases and skin.

I am assuming these are adult stem cells, since the type was not mentioned in the story, which generally means non embryonic. My attempts to find out otherwise were for naught. However, a scientist source I contacted told me, “Has to be ASC; they haven’t formed much in the way of an actual organ, in lab or in body, with ESC.” However, if I find out differently, I will let you all know. But even then, the IPSCs continue to come on strong, now having been made with blood cells.

So, if this works—always a big if in early research—a patient’s adult stem cells could be used to grow a new organ in a sheep, which would then be transplanted back to the human when the time was right:

“We have made some very big advances here. There has historically been work on the potential of sheep as producers of human blood, but we are only slowly coming closer to the point where we can harvest sheep for human organs,” Professor Hanazono told The Times. “We have shown that in vivo (in a living animal) creation of organs is more efficient than making them in vitro (in a test tube)... “

So, to those animal rights types: Is it wrong to sacrifice sheep in order to literally save people?