Two Pigs Engineered to Have Monkey Cells Born in China

Pig-primate chimeras have been born live for the first time but died within a week. The two piglets, created by a team in China, looked normal although a small proportion of their cells were derived from cynomolgus monkeys.

“This is the first report of full-term pig-monkey chimeras,” says Tang Hai at the State Key Laboratory of Stem Cell and Reproductive Biology in Beijing.

The ultimate aim of the work is to grow human organs in animals for transplantation. But the results show there is still a long way to go to achieve this, the team says.

Hai and his colleagues genetically modified cynomolgus monkey cells growing in culture so they produced a fluorescent protein called GFP. This enabled the researchers to track the cells and their descendants. They then derived embryonic stem cells from the modified cells and injected them into pig embryos five days after fertilisation.

More than 4000 embryos were implanted in sows. Ten piglets were born as a result, of which two were chimeras. All died within a week. In the chimeric piglets, multiple tissues –...