Researchers from the Cincinnati Children's Hospital Medical Center used 3D imaging to show molecular transactions that occur during the earliest stages of pregnancy, according to a recent Cincinnati Children'srelease.
The study, published online Feb. 9 in Nature Communications, demonstrated in mice that glands in the uterus directly communicate with the embryo to implant and begin pregnancy. The researchers' motivation behind the study was to help address high rates of preterm birth and infant mortality, according to the press release.
"We show that glands nourish the embryos within the crypt by forging a direct connection between the two entities," said the study's senior investigator, Sudhansu K. Dey, PhD, the director of reproductive sciences at Cincinnati Children's, in a statement. "The gland secretions produce molecules essential to embryo development. Without Vangl2, the glands do not extend and connect to the embryo, and the embryo does not properly implant."
According to study methods, researchers compared normal mouse pregnancies to malformations in the uterus of a mouse when the Vangl2 gene is deleted from the uterus lining and glands.
The protein in the Vangl2 gene helps control cell movement and spatial arrangement in developing tissues, which researchers noted occurred inside normal (and healthy) mouse pregnancies. According to study results, researchers also found the embryo connected to the uterine lining correctly inside the uterus' crypts, or implantation chambers.
Additionally, researchers disrupted embryo implantation and pregnancy in other mice to learn that the growth factor protein HB-EGF works with the Vangl2 gene to initiate implantation to begin pregnancy.
Researchers saw with 3D imaging technology that implantation did not occur, and uterine glands formed improperly in the mice. Embryo-sized beads on a string soaked with HB-EGF were transferred into the mice uteri and iniated implantation in the uterine crypts as if it were a real embryo, according to study results.
"[T]he study opens doors to future research possibilities in other animal models that more closely approximate human pregnancy" and "advanced imaging technologies today, including some forms of magnetic resonance imaging, might allow observation of human pregnancy displaying uterus-gland interaction in normal and abnormal pregnancy," according to the press release.