CIENCIASMEDICASNEWS: BioEdge: Japanese scientist to use human-animal hybrids to create organs

domingo, 4 de agosto de 2019

BioEdge: Japanese scientist to use human-animal hybrids to create organs

BioEdge: Japanese scientist to use human-animal hybrids to create organs

Bioedge

Japanese scientist to use human-animal hybrids to create organs

by Michael Cook | 3 Aug 2019 |

A Japanese stem cell scientist has obtained permission to create human-animal chimeras and transplant them into surrogate animals. Hiromitsu Nakauchi, a researcher at the University of Tokyo and at Stanford University, plans to insert induced pluripotent human cells into mouse embryos. His ultimate aim is to grow human organs in animals.

This kind of procedure was banned in Japan until March, when the government issued new guidelines permitting scientists to create human-animal embryos which can be brought to term. The creation of chimeras in the laboratory is permitted in other countries, like the United States, but the human-animal hybrids cannot be brought to term.

Nakauchi says that he will proceed cautiously and slowly, first with mice, then with rats, and then with pigs. “It is good to proceed stepwise with caution, which will make it possible to have a dialogue with the public, which is feeling anxious and has concerns,” science-policy researcher Tetsuya Ishii, of Hokkaido University, told Nature.

Bioethicists fear that the human stem cells could migrate to the brain of the developing embryo and create some form of human consciousness. But Nakauchi says that this will not happen in his experiment. “We are trying to ensure that the human cells contribute only to the generation of certain organs,” Nakauchi told a Stanford magazine. “With our new, targeted organ generation, we don’t need to worry about human cells integrating where we don’t want them, so there should be many fewer ethical concerns.”

Michael Cook is editor of BioEdge

The ever-volatile issue of stem cell research is back on the boil. Earlier this week a Japanese researcher announced that he would be creating human-mouse chimeras -- and bringing them to term. This is controversial stuff, but at least the researcher waited until he had obtained a thumbs-up from Japanese authorities.

Not to be outdone, a Spanish researcher announced soon afterwards this week that she and her colleagues in Spain and the United States are going to create human-monkey chimeras.

Monkeys? Isn't this even more controversial? Yes, of course it is, she told the media. But it's OK: we're doing it in China where ethical standards are lower.

How do you classify that sort of attitude toward ethics? Arrogant? Undemocratic? Secretive? Publicity-hungry? Immoral? Take your pick.