Children's immune system affected by maternal intestinal flora
The intestinal flora has a decisive influence on the immune system and our health. Scientists from the German Cancer Research Center (DKFZ), the Inselspital and the University of Bern as well as the ETH Zurich have now found out that the intestinal bacteria of the mother already form the baby's immune system during pregnancy.
According to the current results of the researchers, the composition of the intestinal bacteria in the mother has a decisive influence on the immune system of the newborn. So far, it was assumed that an adaptation to the child's own intestinal flora only took place after birth. But obviously the baby's immune system is ready for contact with bacteria before birth. "Bacteria already form the baby's immune system in the mother's intestine during pregnancy," the DKFZ said. The researchers have published their study results in the renowned science magazine.
Bacterial molecules are transferred
According to the scientists, babies are born with an immature immune system and until now it was assumed that the newborn only began to adapt to the many bacteria in its own intestinal flora after birth. However, the researchers were able to demonstrate in their studies on mice that the intestinal flora of the mother prepares babies for microbial colonization after birth, even during pregnancy. Bacterial molecules that pass through the placenta or are transmitted via antibodies in breast milk are said to be responsible for the effect.
Sudden confrontation with countless bacteria
With birth, the child suddenly moves from the sterile, protected environment of the uterus into a world full of bacteria. The DKFZ explains that microorganisms colonize all body surfaces shortly after birth. After just a few days, ten times as many bacteria can be found in the intestine as cells in the whole body. Nevertheless, the newborn babies normally survive the sudden wave of invading bacteria without problems. Globally, however, millions of children under the age of five die annually from intestinal infections. According to the researchers, the biggest problem after birth is that the gut has to be colonized with microbes "without infecting the newborn, without causing a strong immune response, and without restricting the intestinal capacity to absorb nutrients."
Baby's immune system is being prepared
According to the current findings of the scientists, the baby's immune system is prepared for contact with bacteria before birth. The DKFZ reports that molecules of the bacteria that live in the mother's intestine first penetrate into the mother's body and can then be passed on to the child via the placenta or after birth via antibodies contained in breast milk. These bacterial components are harmless and do not cause infection. Instead, they would stimulate cells in the baby's body and prepare their immune system and intestines for the moment after birth, when the newborn has to deal with living bacteria in its own intestines. Research director Andrew Macpherson from Inselspital Bern emphasizes: “We always knew that we should be grateful to our mothers for their love and protective affection. Now we know that we should also thank them for their intestinal flora. "(Fp)