Magnified image showing a human egg enclosed by multiple sperm cells, at a scale of 400.
In a groundbreaking study published in the journal Nature Medicine, a team led by Melina Schuh at the Max Planck Institute for Multidisciplinary Sciences has discovered a new type of stem cell in the human ovary. These stem cells, capable of generating immature egg cells, could potentially revolutionise fertility treatments.
The team identified these ovarian stem cells using a unique gene-encoded protein found in germ cells, including eggs, sperm, and their precursor cells. Justin Lathia, an assistant professor of cell biology, considers the isolation of these stem cells via fluorescence as the real advance of the study.
The same immature cells isolated from adult mouse ovaries can turn into fertile eggs, a finding that was replicated in the human tissue used in the study. Within one to two weeks, the fluorescent human stem cells had developed into fluorescent immature egg cells, indistinguishable from the egg cells already present in the tissue.
The discovery of these ovarian stem cells could have significant implications for women's health. According to the study, as women age, they stop producing new egg cells, a process that may be reversed by these stem cells. This could potentially delay or halt menopause, an idea that Tilly, one of the study's researchers, finds promising.
Tilly also addressed the common misconception that the existence of these egg precursor cells in women during their reproductive years conflicts with the fact that fertility and ovarian function decline with advancing age. He clarified that these findings do not contradict this fact, but rather offer a potential explanation for it.
The rejuvenated mouse, injected with the fluorescent-tagged stem cells, later avoided many of the health problems associated with ovary failure, such as osteoporosis and muscle loss. This suggests that these stem cells could offer a solution to the health issues that women face as they age.
The technique to isolate these rare ovarian stem cells is especially important, as they make up fewer than one percent of the ovary's total cell count. Lathia notes that this technique will be crucial for future research and potential applications in medicine.
Down the road, scientists could potentially use a woman's egg stem cells to create an 'unlimited supply' of eggs, which could improve or even replace difficult fertility treatments. This discovery offers hope for women struggling with infertility issues, and could pave the way for a new era in reproductive medicine.
