How natural killer cells promote embryo growth
Researchers observed natural killer cells in large populations at the interface between the mother and her embryo in women during early pregnancy. However, the role of killer cells in embryonic growth has so far been unclear. But now Chinese scientists from the University of Science & Technology of China in Hefei have decoded the function of the killer cells. Apparently, the killer cells secrete molecules that promote the growth of the embryo.
Pregnancy is a complicated process that requires both promoting embryonic growth and maintaining immune tolerance. Among the immune cells, the natural killer cells, which are cellular components of the blood, are only present in large populations at the mother-embryo interface during early pregnancy and decrease when the placenta is formed. In the current study, which was published in the journal "Cell Immunity", the researchers document the unique abilities of the killer cells on the development of the embryo.
Killer cells as development aid
According to the scientists, the killer cells influence a variety of processes in the early embryonic growth phase. This includes promoting placental vascular growth, decidualization, trophoblast invasion, and immune imbalance. The killer cells secrete molecules that have a direct influence on placentation and birth weight. A lower population of these killer cells was also found in women who had miscarriages. The Chinese scientists were able to establish a further connection in experiments with pregnant mice. The growth of the unborn mice was significantly disturbed due to a lack of killer cells.
Therapy against miscarriages is conceivable
The results of the study show the properties of natural killer cells in promoting embryonic growth. In addition, approaches for the therapeutic administration of natural killer cells are proposed in the work in order to counteract certain abnormal processes in the early pregnancy phase. "The adoptive transmission of induced uterine-like natural killer cells as a cell treatment for fetuses has many advantages," write the authors of the study. The killer cells could be transmitted to the mother intravenously or via a vaginal suppository without the need for invasive intervention. This procedure would be much gentler on the mother and fetus. According to the researchers, additional studies are needed to induce uterine-like killer cells in a human system. The feasibility of application in patients also needed to be improved. (fp)