Human-animal hybrid embryos may one day provide transplant organs
Growing human organs in other animals is a small step closer to reality.
Injecting human stem cells into pig and cattle embryos created embryos that incorporate a small number of human cells, scientists report January 26 in Cell. The ultimate goal of the controversial research is to use hybrid, or chimeric, animals to produce human organs for transplant.
Farm animals incubating human organs won’t appear anytime soon, says Juan Carlos Izpisua Belmonte, a stem cell biologist at the Salk Institute for Biological Studies in La Jolla, Calif. “I feel we’re still far away from that,” says Belmonte, who led the work. It has taken his group four years “just to deliver a message that, yes, human cells can integrate into a pig.”
While human-animal chimera work is still in its infancy (and faces ethical and funding hurdles, see sidebar), hybrids of rats and mice are already hinting that growing an organ from