In an article published in the journal Nature , a team of researchers from different Japanese institutions, coordinated by Katsuhiko Hayashi, from the Department of Medicine and Stem Cell Biology at Kyushu University, describes a process that allows obtaining fully functional eggs from embryonic and pluripotent stem cells.
The scientists took cells from mouse embryos and from the skin of the tail of these rodents and obtained from them primordial germ cells, the precursors of gametes. To do this, they induced the expression of certain genes and mixed the aforementioned cells with other somatic cells from the female gonads. The experts observed that, in this way, the cells began to express the characteristic markers of oocytes, that is, they behaved as if they were real ovaries , but reconstructed in the laboratory.
After stimulating the development of ovarian follicles, small structures that grow in the ovary and release eggs during ovulation through hormones and other chemicals, Katsuhiko and his colleagues were able to achieve healthy and functional eggs. They then used IVF techniques to produce hundreds of embryos and implant them into female mice. Although only a few of those pregnancies came to fruition, some produced fertile mice that, in turn, later had their own offspring .
The study sheds some light on the process of formation of female gametes and the ability of totipotent cells to become any other in the body, a phenomenon that is not yet well understood. However, this technique presents numerous complications . For example, scientists point out that more abnormalities ended up occurring during in vitro development than if the process had been natural. Furthermore, its possible application to treat infertility in humans –something still distant– presents ethical problems, since, for now, to put it into practice it is necessary to generate embryos and destroy them.
Image: Katsuhiko Hayashi
