A Japanese scientist has teamed up with a group of German researchers to try to save the nearly extinct northern white rhinoceros by producing eggs from induced pluripotent stem (IPS) cells.

There are currently just three of the animals left alive — one male and two females, living in a nature preserve in Kenya, according to Katsuhiko Hayashi, a professor of reproductive biology at Kyushu University.

The animals cannot breed naturally due to age or disease.

If Hayashi and the team from the Leibniz Institute for Zoo and Wildlife Research in Berlin successfully produce eggs, then the next step would be to fertilize them in vitro with frozen semen, and then impregnate a closely related animal, possibly a southern white rhinoceros, he said.

With little relevant data available, the team will have to start with basic research, according to Hayashi. "The implementation will take a long time," he said.

Hayahsi, who has produced eggs from the iPS cells of a mouse from which mice have been born, said he has provided the German team with technical guidance.

Northern white rhinoceroses were originally distributed across central Africa with a population of about 2,300 in the 1960s. But the animals, whose horns are prized in Chinese medicines, have seen their numbers fall dramatically due to hunting.

Civil wars in the region have also affected their decline, with no wild northern white rhinoceros has been confirmed since 2006.

In human medicine, research is underway to apply iPS cells in regenerative medicine and drug development as the cells can grow into various human body tissues.