Discovery sheds light on abortions: Breast failure could trigger heart failure for pregnant women, researchers say
- Developing a baby – a foreign object – is a challenge to the mother’s immune system
- Research has shown that the thymus gland plays a key role in ensuring baby rejection
- It will allow the development of drug treatment to prevent miscarriages
Malfunctions in the small gland in the breast can cause miscarriage in pregnant women, researchers say.
A developing baby – in fact a foreign object – is a huge challenge for the mother’s immune system.
The researchers ’discovery that the thymus gland, located behind the breast bone, plays a key role in ensuring that the mother’s immune system does not reject the baby, will allow the development of drugs to prevent miscarriage.
Researchers from the University of British Columbia and the Swedish Karolinska Institute, writing in the journal Nature, discovered that during pregnancy, the thymus creates cells known as regulatory T-cells or “traces”.
A developing baby – in fact a foreign object – is a huge challenge for the mother’s immune system
When you produce too few of them, miscarriage can occur.
Dr. Joel Penninger from UBC said that the study showed that the thymus is “necessary for the protection of pregnancy”.
The researchers further found that the traces did not occur when the thymus did not have a property called the RANK receptor.
RANK receptors are molecules on the surface of the thymus that trigger the production of Treg cells after they come into contact with female sex hormones during pregnancy.
Dr Magdalena Paolino, lead author of the study and an assistant professor in the department of medicine at the Karolinska Institute, said: ‘The absence of RANK prevented the production of Tregs in the thymus during pregnancy. This resulted in fewer Tregs in the placenta, leading to an increased abortion rate. ‘
The findings also offer new molecular insights into the development of diabetes during pregnancy, a disease that affects about 15 percent of pregnant women worldwide and about which scientists still know little.
UBC’s Dr. Joel Penninger said the study found that the thymus was “needed to protect pregnancy.”
In a healthy pregnancy, researchers found that Tregs migrated into the mother’s adipose tissue to prevent inflammation and help control glucose levels in the body.
Pregnant mice without RANK had high blood glucose and insulin levels and many other indicators of gestational diabetes, including younger than average ones.
Dr Paolino said: ‘Similar to the babies of women with diabetes in pregnancy, newborn cubs [baby mice] were much heavier than average. ‘Mice grew up to be prone to diabetes and overweight during their lifetime.
The researchers also analyzed women with diabetes in pregnancy, finding a reduced number of Tregs in their placenta, similar to a study in mice.
Dr Alexandra Kautzky-Willer, a clinical researcher with the Medical University of Vienna, added: “The discovery of this new mechanism underlying gestational diabetes potentially offers new therapeutic goals for mother and fetus in the future.”