PIONEERING research in stem cell biology has discovered that a protein evolved from a viral infection in primates 25 million years ago may enhance treatment for stressful obstetric complications by aiding the effective implantation of embryos in the womb.
A team of scientists led by Prof Harry Moore, Co-director, Centre for Stem Cell Biology, University of Sheffield, Sheffield, UK, observed that the syncytin 1 protein is first released on the surface of the developing embryo prior to implantation in the womb. The implications of this process are essential for ensuring a healthy pregnancy; syncytin 1 enables embryos to stick to the lining of the womb and plays a key role in the development of the placenta.
“Until now we did not know this protein was expressed so early in the embryo,” Prof Moore remarked. After monitoring the activity of syncytin 1, it appeared that the protein was largely secreted in the polar trophoblast cells of the embryo, which then attached to endometrial epithelial cells in the womb, forming a protective barrier around the newly formed embryo. In addition, the trophoblast cells were notably found to secrete nanovesicles known as exosomes which transmit information to other cells in the body, therefore aiding the reproductive process. “These exosomes may communicate with cells in other areas of the mother to prepare her for pregnancy. If this does not happen properly at the earliest stages it may cause problems throughout pregnancy,” explained Prof Moore.
In future studies, the team plan to expand their research into other areas of reproductive medicine by investigating the impact of syncytin 1 secretion on pre-implantation embryos in in vitro fertilisation. As obstetric complications have hit headlines in recent months with extensive coverage of the Zika virus, this breakthrough has come at a crucial time and provides hope for future treatment in problematic cases such as recurrent miscarriage, foetal growth restriction syndrome, and pre-eclampsia. “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,” Prof Moore concluded.