The researcher Hiromitsu Nakauchi has announced that an experiment is starting in Japan to culture a human pancreas in pigs. This statement comes as Japan has just relaxed its legislation on chimeras [1]. Nevertheless, Nakauchi still needs to obtain approval from the university and government regulatory committees.
He plans to inject human induced pluripotent stem cells into genetically modified pig embryos. These iPS cells will take the place of the removed gene in the embryos to create a human pancreas. The chimera embryo will then be implanted into a carrier sow’s uterus. The foetus will be removed before birth to study how much pancreatic tissue is derived from human iPS cells and how it functions.
[1] Japan now allows animal-human chimera embryos to be implanted into animals. Implanting chimeric embryos into humans is still prohibited, as is reproducing the chimeric animals resulting from these experiments.
Japan Times (28/04/2019)