Research has indicated that babies get many benefits from breastmilk, even if they are only fed that way for a very short period of time. Moms can pass many beneficial molecules on to their babies that way and can help protect babies from infection. As such, women are encouraged to breastfeed if possible. A new study has suggested that breast milk may help prevent a common cause of stillbirth, meningitis, and blood infections: a bacteria called group B Streptococcus (GBS). It's estimated that there about 2,000 infants are infected with GBS every year in the US, and four to six percent don't survive the infection. These infections are usually preventable or treatable with antibiotics, but antibiotics can have unwanted, disruptive impacts on the infant microbiome, and GBS are also becoming resistant to standard antibiotics.
This study, which was reported at the the fall meeting of the American Chemical Society (ACS), has suggested that the sugars in breast milk, called human milk oligosaccharides (HMOs), may one day replace antibiotics as a GBS preventative or treatment. The research used cell culture and mouse models to show that HMOs help stop GBS from infecting cells.
“Our lab has previously shown that mixtures of HMOs isolated from the milk of several different donor mothers have antimicrobial and antibiofilm activity against GBS,” said study presenter Rebecca Moore, a graduate student at Vanderbilt University. “We wanted to jump from these in vitro studies to see whether HMOs could prevent infections in cells and tissues from a pregnant woman, and in pregnant mice.”
GBS can be transferred from mom to baby during delivery, and there are more infections that are considered late-onset (they occur one week to three months after delivery), in babies that are fed with formula compared to infants that are breastfed, which may confirm these findings.
In this work, the scientists isolated HMOs from several moms, and looked at the influence of these sugars on immune cells called macrophages and cells from the placenta membrane that had been exposed to GBS.
“We found that HMOs were able to completely inhibit bacterial growth in both the macrophages and the membranes, so we very quickly turned to looking at a mouse model,” said Moore. HMOs also reduced GBS infection in the reproductive tracts of pregnant mice.
The researchers are performing additional tests with microbiome models to determine which HMOs may be impacting GBS. They suspect that the sugar or sugars that help suppress the infection may be stopping the bacterial pathogens from forming dangerous biofilms, and may also promote the growth of healthy microbes.
Researcher Steven Townsend, Ph.D. of Vanderbilt University suggested that if we learn more about HMOs, “it’s possible that we could treat different types of infections with mixtures of HMOs, and maybe one day this could be a substitute for antibiotics in adults, as well as babies.”