Adult stem cell eggs could cure infertility

Japanese scientists raise hopes for curing infertility after successfully breeding mice from adult stem cells.

Scientists recently reported that they had successfully created viable eggs using normal embryonic cells from adult mice.

This is a significant breakthrough as it is the first time anyone has managed to create eggs that have resulted in healthy babies.

The team have gone one step further however, managing to breed healthy mice from eggs created from another type of stem cell known as induced pluripotent stem cells.

According to a Boston’s news station WBUR these cells look similar to emryonic stem cells but don’t come from embryos. Instead, they can be extracted from adult cells found in skin or blood.

This means that many of the ethical and moral concerns associated with embryonic stem cell research, which results in the destruction of the embryo, don’t apply.

Religious conservatives, amongst others, object to research on human embryonic stem cells because they believe that the resulting destruction of a foetus is wrong.

The recent experiments however combined adult stem cells and a number of altered genes to create cells very similar to the primordial germ cells that generate sperm in men and eggs in women.

They then developed these with cells that would become ovaries and transplanted the mixture into living mice, where the cells matured into fully-grown oocytes.

They extracted the matured oocytes, fertilised them in vitro in a test tube and implanted them into surrogate mother mice.

AFP reported that the mice pups were born healthy and had the ability to reproduce once they matured.

The development raises the possibility that women who are unable to produce eggs naturally could have them created in a test tube from their own cells and then implanted back into their body.

In a current issue of Science, adjunct professor at Kyoto University in Japan, Mitinori Saitou said: “This is actually the first time to make eggs from embryonic stem cells and then produce eggs [that] become healthy offspring.”

The team at Kyoto University believe that this success could eventually be re-created using human cells.

Such use, however, brings a whole new set of issues. Dr Bryce Vissel, an Australian stem cell expert stated that such work on humans would be ‘fraught with scientific challenges and hurdles, including major questions relating to viability, reliability and safety’.

Even without the involvement of emryonic stem cells, this research is also not without other ethical and moral challenges.

Some experts have noted that the potential of such work could have far-reaching consequences, noting that it could eventually lead to parents being able to pick their children’s physical characteristics and talents with far greater ease than is currently possible.

Ronald Green, a bioethicist at Dartmouth University, went further, noting that “Any skin cell that you can find on the edge of a coffee cup theoretically could be induced back to being an egg, and a baby could be produced.”

However, the big differences between mice and people and the need for extensive safety testing mean that test-tube eggs are still at least a decade away from use in fertility clinics.

The news is still exciting scientists. Researcher Katsuhiko Hayashi said that those who could benefit in the future included young cancer patients and post-menopausal women, the DailyMail reports.

The work could also lead to new fertility drugs, but a change in the law is needed if the treatment is to be used in the UK.