A research team from the University of British Columbia (UBC) has worked on a small gland in a woman’s body that has never been studied before. This gland is called a thymus gland and it is involved in saving pregnant women from the risk of a miscarriage and gestational diabetes which may show up during pregnancy.
This is the first time that the function of this gland has been revealed. The thymus gland is located at the backside of the sternum. The complete study findings are published in the journal Nature.
The exact mechanism on how a mother ‘creates’ immunity for her baby has been unclear for decades. This study which is organized by an international team has tried to unveil this mystery, explaining the real reason behind it. According to them, the sex hormones in women change the action of the thymus which then produces special cells which are called Tregs. These cells are behind all the physiological changes which show up during pregnancy.
They have found a receptor found in the epithelium part of the thymus gland which plays a vital role in this mechanism. Although the presence of RANK was already known how it may affect a pregnancy wasn’t clear before this study.
To understand how RANK works, they studied its function in mice with removed RANK from their thymus.
When RANK is limited, the Tregs cell production inside the thymus also stops, during the pregnancy. It means that a lesser number of Tregs are present inside the placenta, which connects the mother and the baby. This is a highly threatening situation where the mother can even experience a miscarriage too.
In addition to this, the research team also tried to find out the molecular mechanism involved in gestational diabetes, which shows up during the pregnancy. Although it sounds rare is extremely common and nearly 15% of all pregnant women develop it. There is no clear evidence on what causes it during the pregnancy.
In healthy mothers during pregnancy, Tegs travel from the mother’s body to get a hold over inflammation and glucose regulation. Mice without RANK experienced a very high level of sugar as well as insulin with unexplained inflammation inside their bodies which are the primary signs of gestational diabetes. These diabetic mothers then give birth to heavier babies, who weigh much more than an average human baby.
The absence of Tregs in a pregnant mother also leaves long term effects on the baby. It is possible for such babies to become diabetic later in their lives and gain unhealthy weight.
When the research team incorporated RANK-deficient lab mice these thymus-extracted Tregs, all their health issues were improved. The risk of miscarriage reduced and the glucose levels in the mother also improved. Eventually, the newborns in these mice weighted normal.
Like these mice, the research team also found the same results among women with a low number of Tregs inside their placenta during pregnancy.
This new discovery has highlighted the therapeutic role of thymus-derived Tregs which can improve the health of the mother and the baby. The action of the Thymus gland changes during the pregnancy and rewiring of this whole gland and its role in pregnancy has unveiled one of the most significant immunological mysteries in medical sciences.