Growing human organs inside pigs in Japan

Meiji University professor Hiroshi Nagashima is creating chimeric pigs, which carry genetic material from two different species, BBC News reports. It starts off by making what Nagashima calls “a-pancreatic” embryos. Inside the white pig embryo, the gene that carries the instructions for developing the animal’s pancreas has been “switched off.”

The Japanese team then introduces stem cells from a black pig into the embryo. What they have discovered is that as the pig develops, it will be normal except for its pancreas, which will be genetically a black pig’s.

In a lab at Tokyo University, Professor Hiro Nakauchi is taking the next step. He takes skin cells from an adult brown rat. He then uses gene manipulation to change these adult skin cells into induced pluripotent stem cells (iPS) cells, which can develop into any part of the animal’s body. Nakauchi has succeeded in using these iPS cells to grow a brown rat pancreas inside a white mouse. He is hoping to develop a technique to take skin cells from a human adult and change them in to iPS cells. Those iPS cells can then be injected into a pig embryo.