One of the challenges of science may be closer: that women with fertility problems can have their own eggs, healthy, and get pregnant. A new investigation has managed to obtain human egg precursors from ovarian stem cells.
This is a work by the controversial American researcher Jonathan Tilly, a reproductive biologist at the Massachusetts General Hospital, recently published in the journal Nature Medicine with the title of "Oocyte formation by mitotically active germ cells purified from ovaries of reproductive-age women".
The results could lead to new therapies that help extend female fertility in adulthood, even after menopause. The author points out that it is a milestone:
For the reproductive health of women these results have many consequences. If we can reach the stage of generating functional human eggs outside the body, we would essentially rewrite human assisted reproduction.
For more than 50 years there is the conviction that women are born with a limited number of germ cells that mature and produce eggs in a process that continues throughout fertile life until menopause arrives.
Faced with this concept, firmly established in the scientific community, Tilly has published several articles that question him. In them he defends that there are adult stem cells in the ovary that could have a role in egg production.
The last of these works is a great step in his research since he has made the leap of animals, in which this issue had already been investigated, to the human species.
The experiment
Tilly, along with his team at the Vincent Center for Reproductive Biology at the Massachusetts hospital (Harvard University), says he has located adult stem cells in human ovaries, something I had already done in mice.
After isolating these cells, which he obtained from ovarian tissue donated by women who underwent a process of sex change, he cultivated them and, in the laboratory, the cells generated immature oocytes (oocytes) of the same characteristics as humans.
When transferred to human grafted ovarian tissue in mice, these cells produced follicles (germ structures of the ovules). The key would be to find a way to activate the cells to generate gametes.
In other words, we are facing a possible new reproductive technique: New ovules could be produced from old ovaries, adding this solution to those currently in existence (who knows if replacing them), such as egg preservation programs or donation.
However, this line of research to which Tilly is dedicated is very controversial, and different groups that have tried to reproduce previous works in Tilly mice have failed, although there are others who did approach the results of this last work.
Several research teams in assisted reproduction and stem cells from around the world will attempt to reproduce the results and conclusions of Tilly.
At the moment it seems that the discovery of stem cells in the ovary is a great advance against infertility, although surely we will have more news about it, and new research fronts in this regard. It seems that the human being is not resigned to the miracle of life having an expiration date on women.
