Scientists have unlocked a longstanding mystery about the function of certain immune cells during pregnancy in a revelation that may have important ramifications on maternal and infant health.
Led by Dr. Kang Chen of Wayne State University, a group of researchers discovered that a mother’s immune cells known as B lymphocytes are present in the uterine lining during pregnancy. These immune cells are vital to a healthy pregnancy because they suppress inflammation during an infection – which is the leading cause of preterm birth.
Scientists previously thought that the B lymphocyte cells were not found in the uterine lining and not relevant to the health of the mother or baby.
The groundbreaking research turns that conventional understanding of these unique immune cells on its head and offers hope for near-term therapies that can prevent preterm birth.
“This study not only reveals the long-neglected function of B lymphocytes in promoting healthy pregnancy, but also supports therapeutic approaches of using B lymphocyte-derived molecules, such as PIBF1, to prevent or treat preterm birth,” said Dr. Chen, assistant professor of obstetrics and gynecology at Wayne State University, in a statement.
As it turns out, the B lymphocytes create molecules, such as PIBF1, that can “detect inflammation and uterine stress” and suppress the infection-triggered inflammation from leading to an early birth.
About one in 10 babies is considered to be born preterm, which happens when the baby is born before 37 weeks of pregnancy, according to the Centers for Disease Control and Prevention (CDC).
Preterm birth is a serious issue. It’s the “leading cause of neonatal death worldwide,” note the researchers in the journal Nature Medicine. Babies born earlier than 37 weeks also face a greater chance of serious disability because vital organs, such as the brain, lungs and liver, are still developing during the final weeks of pregnancy. The CDC notes that preterm birth can lead to problems such as breathing issue, developmental delay, vision and hearing problems and cerebral palsy.
Some women are more likely to experience preterm birth than others. Some behavioral factors, such as high stress or tobacco or alcohol use, can result in an early delivery. Other conditions, including high blood pressure or carrying twins, can cause preterm birth.
And infection, the researchers note, is a “common trigger.”
The researchers found evidence of B lymphocytes in the uterine lining of both humans and mice. So far, the researchers have conducted “proof-of-concept and efficacy studies” in mice but have not yet tested a therapeutic approach in human. They believe that will happen in the near future; recently, the team filed a patient for a potential treatment therapy.
“It is truly remarkable that Kang has independently convened and led a team of outstanding scientists to accomplish this original and impressive tour de force, especially considering the many challenges he has encountered in the process,” said Dr. Chen’s collaborators, which included scientists and clinicians from Wayne State University, Beaumont Dearborn Hospital, Yale University, Memorial Sloan-Kettering Cancer Center, Washington University in St. Louis and Icahn School of Medicine at Mount Sinai.