A protein that helps the human placenta develop has the potential to treat recurrent miscarriages and pre-eclampsia, a life-threatening condition that causes high blood pressure during pregnancy.
Researchers suspect the protein, called syncytin-1, could help embryos implant in the womb. It’s first secreted on the surface of a developing embryo even before it implants in the womb.
“Until now we didn’t know this protein was expressed so early in the embryo.”
“Eventually we may be able to develop blood tests based on our results to identify pregnancies that might be at risk and also develop appropriate therapies,” says Harry Moore, co-director for the University of Sheffield’s Centre for Stem Cell Biology and lead author of the study published in the journal Human Reproduction.
Oddly, syncytin-1 is the result of a viral infection that affected our primate ancestors 25 million years ago.
“The viral DNA got into our ancestor’s genome and was passed on through heredity, and the gene involved in the fusion of the virus with cells for infection was co-opted and became syncytin-1. Without it, humans probably would not have evolved,” says Moore.
Surprisingly scientists know much more about the processes of early embryo development in animals than they do in humans. However, embryo development and reproduction is an aspect of biology where there are fundamental differences between species.
Researchers will now investigate whether the level of syncytin-1 secretion on the pre-implantation embryo is somehow related to outcome of pregnancy in women undergoing IVF.
“Until now we didn’t know this protein was expressed so early in the embryo.
“Interestingly the syncytin-1 protein was mainly secreted in the cells of the embryo, called polar trophoblast cells, which will first stick to the cells of the womb called endometrial epithelial cells.
“In the lab we discovered the trophoblast cells that secrete syncytin-1 not only fuse together—which in the body will form an essential barrier to protect the embryo—but also secrete nano-vesicles called exosomes. These exosomes may communicate with cells in other areas of the mother to prepare her for pregnancy.
“If this doesn’t happen properly at the earliest stages, it may cause problems throughout pregnancy.”
Source: University of Sheffield