A new study by the University of Copenhagen has revealed that regenerative and versatile stem cells in early embryos may hold the key to developing effective fertility treatments.
Pregnancy is a very complex process: First, a sperm cell must find its way to fertilize an egg in the fallopian tube, and the egg begins to divide. After about 5 days, the egg turns into a blastocyst, which eventually develops into an embryo.
But achieving fertility has become more difficult for many people, due to various factors that affect the quality of the sperm or egg.
There are fertility treatments, but their success rate remains low depending on the woman's age and fertility.
Now, researchers have made a clear advance that could lead to more successful fertility treatments in the future.
In this regard, the first author of the study, Madeleine Lenneberg-Agerholm, says: “We looked at cells in the mouse embryo called primitive endoderm, also known as hypoblasts. We found that these cells were unique and could generate an embryo on their own. This is particularly interesting as it indicates A recent study indicates that primitive endoderm is the only cell type in the embryo associated with significant implantation success in clinical studies.
She adds: "Normally these cells only provide nutrition and support to a normal embryo, but when we isolate them, they can reconstruct the embryo on their own, which is a very surprising discovery."
The researchers also found that stem cells from primitive endoderm cultured in the lab develop in a dish to form "stem cell-based embryo models," called blastomeres, with very high efficiency.
These embryo models have the potential to be very important tools that can be used to discover new drugs to improve IVF outcomes.
“This may be particularly important for improving current infertility treatments, as plasticity and robustness may be the secret to enabling embryos to survive the unnatural environmental conditions found in the laboratory,” says Professor Joshua Brickman, lead author of the study.
“The primitive endoderm somehow ‘remembers’ how to form an embryo, and it can do it on its own,” he explains. “We showed that cells in the primitive endoderm remember how to form other cell types because they contain transcription factors located on their DNA in important regulatory sequences (enhancers), like reference signals.”
The researchers hope their findings will shed some light on how to improve IVF treatments.
The research team is looking forward to conducting similar research on human stem cells.
The research paper was published in the journal Cell.