Study Finds Old Order Mennonite Mothers Pass More Egg-Targeting Antibodies Through Breast Milk
Children who grow up in farming communities have long been known to develop far fewer allergies than their urban peers. A new study from the University of Rochester Medical Center (URMC) offers one possible reason why: their immune systems may mature faster, and breast milk appears to play an important supporting role.
In a longitudinal birth cohort comparing infants from Old Order Mennonite (OOM) farming families in New York’s Finger Lakes region with urban and suburban families in Rochester, researchers found that farm-exposed babies had more “experienced” B cells and higher levels of protective antibodies during the first year of life. The study, published in Science Translational Medicine, was led by Kirsi Järvinen-Seppo, MD, PhD, chief of Pediatric Allergy and Immunology at UR Medicine’s Golisano Children’s Hospital.
Kirsi Jarvinen-Seppo, MD, PhD
“We’ve known that Old Order Mennonite children are remarkably protected from allergies,” said Järvinen-Seppo. “What this study shows is that their B cell and antibody responses are essentially ahead of schedule compared to urban infants. their immune systems seem better equipped, earlier in life, to handle foods and other exposures without overreacting.”
Earlier maturation of antibody production
The team followed mothers and babies from pregnancy through the first year of life, collecting cord blood, infant blood, stool, saliva, and human milk samples.While a prior paper from the same NIH-funded cohort focused on T cells, this study examined the B cell arm of immunity-the cells that produce antibodies which can protect against allergies-and how those responses differ between farming and urban lifestyles.
Farm-exposed infants had more memory and IgG+ B cells, suggesting earlier maturation of the antibody-producing system. They also had higher levels of IgG and IgA antibodies in blood, saliva, and stool, and higher IgA levels in human milk from their mothers. Taken together, the data point to a more robust and active antibody system in infants growing up in a traditional farming lifestyle.
One notable finding involved egg-specific antibodies and the advancement of egg allergy, one of the most common food allergies in young children. The researchers measured egg-targeting IgG4 and IgA antibodies in infant blood and human milk, and tracked which infants later developed egg allergy.
They found that OOM infants had higher levels of egg-specific IgG4 in their blood and higher levels of egg-specific IgA in their mothers’ milk. Infants with higher levels of these antibodies were less likely to develop an egg allergy.
“The higher levels of egg-specific antibodies in OOM infants suggest that early exposure to egg proteins through the farm environment,combined with transfer of antibodies from mother to infant through breast milk,may help train the immune system to tolerate egg proteins,” Järvinen-Seppo explained. “This could be a key mechanism behind the lower rates of egg allergy seen in these communities.”
The researchers emphasize that this is just one piece of the puzzle.The farm environment is complex, with many factors that could contribute to immune development, including exposure to microbes, diverse diets, and different lifestyles.Future research will focus on identifying the specific components of the farm environment that are most important for promoting immune tolerance.
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