BioWorld International Correspondent

MUNICH, Germany - Scientists at King's College London are preparing to put in an application seeking permission to use the enucleated oocytes of rabbits, cows and pigs to generate human clones for use in the production of embryonic stem cell lines.

Speaking at the Euroscience Open Forum in Munich last week, Stephen Minger, head of the stem cell laboratory at King's said he was "getting vibes" that the UK regulator, the Human Fertilisation and Embryology Authority (HFEA), would welcome an application.

The authority previously granted two licenses allowing researchers to attempt to create human clones using donated human eggs and currently is consulting on whether altruistic donations of eggs (as opposed to use of eggs left over after in vitro fertilization treatment) should be allowed.

But Minger believes that since South Korean scientist Woo-suk Hwang's claims to have created 11 patient specific embryonic stem cell lines were discredited, it is not appropriate currently to ask women to donate oocytes for research.

"At best, this is an unpleasant procedure, and there are risks of overstimulating the ovaries, so I think it is unethical to encourage donations. At present, the efficiency is such that you could be asking 20 to 30 women to go through a procedure for no medical benefit from which you might at best get one cell line," he told BioWorld International.

While embryonic stem cell lines derived by putting the nucleus of an adult human cell into the enucleated oocyte of another mammal would have no therapeutic use, doing the work would enable researchers to refine and practice cloning techniques. That may make them more successful in working with human eggs.

Oocytes from animals could be used also to generate disease-specific embryonic stem cell lines for use in drug discovery.

Minger previously visited the laboratory of Hui Sheng, a researcher at Shanghai Medical University in China, who in 2003 published data showing she had generated human stem cell lines from embryos produced in enucleated rabbit oocytes. He will make another visit over the summer and said he is keen to get as much details as possible on how to go about such work.

Minger came to the UK from the U.S. in order to pursue his research, and has since become a British citizen. Speaking the day before President Bush vetoed legislation to expand federal funding for embryonic stem cell research, Minger said that although the research is not banned, the 20 cell lines scientists in the U.S. are allowed to work with "are not the best in the world. The big problem is that people who would do embryonic stem cell research don't."

He said he has friends working in the field in U.S. universities who have been told not to talk about their work. "I'm glad to have a UK passport. [In the UK] there are 10 to 15 research groups, and we are proud of what we do."

However, the unevenness in the law across Europe does pose problems. Minger has German PhD students working in his lab who fear they may be prosecuted when they return to Germany, where all embryonic stem cell research is banned. "We are trying to clarify the situation at present," Minger said.