In an experiment that raises bioethical issues, researchers in China have generated a blueprint of a humanized kidney in a pig embryo<\/p>\n
It is a historic image. A team of researchers in China has successfully generated a blueprint of a human organ in another animal for the first time. The experiment, conducted with humanized kidneys in pig embryos, represents a step toward the still-distant dream of using other mammals as an inexhaustible source of organs for transplants. These hybrid organisms \u2014 called chimeras, after the mythological monster with the head of a lion, the belly of a goat and the tail of a dragon \u2014 still pose major ethical dilemmas.<\/p>\n
Researchers at the Guangzhou Institute of Biomedicine and Health have reprogrammed adult human cells to recover their capacity to form any bodily organ or tissue. The team has inserted these pluripotent human cells into pig embryos, which are genetically modified beforehand so that they do not develop porcine kidneys. The human cells have filled that empty niche and generated a rudimentary kidney, an intermediate stage of the renal system called mesonephros. These pig-human embryos were gestated in sows for up to 28 days, about a quarter of the species\u2019 normal period of pregnancy. Half of the cells in their kidneys are human.<\/p>\n