Nothing to Sneeze at: Study Seeks to Understand Allergic Resistance of Old Order Mennonites

Apr. 19, 2023

With a $7 million grant from the National Institute of Allergy and Infectious Diseases (NIAID), pediatric researchers at the University of Rochester Medical Center (URMC) will study the farming lifestyle of the Old Order Mennonite population and its correlation with lower rates of allergic disease.

This research will build on a foundation established by several studies, including two led by Kirsi Jӓrvinen-Seppo, MD, PhD, chief of Pediatric Allergy and Immunology and Founders' Distinguished Chair in Pediatric Allergy at URMC. A cross-sectional study started in 2014 examined biologic samples from Rochester urban infants and the Old Order Mennonite (OOM) population— groups of Swiss German and south German heritage who practice a lifestyle without elements of modern technology, such as driving a horse-and-buggy rather than cars and exposure to unpasteurized farm milk. The most recent project, started in 2017, was a longitudinal birth study that examined allergy resistance in this population from an early age compared to urban-suburban Rochester infants.

Both studies found reduced allergic sensitization and reduced susceptibility to development of allergic diseases in OOM children compared to the control group of Rochester city children.

“The first study showed that Old Order Mennonite children and adults have this protection, and the second study showed the same to be the case in infants,” said Jӓrvinen-Seppo. “Taking these early life samples revealed novel findings that we will examine in greater detail in this new study.”

“We want to find answers as to how exposure to this traditional farming lifestyle for mothers and infants fundamentally alters their susceptibility to allergic disease and how we can use these findings for preventive strategies for the rest of the population,” she added.

The new study—which Jӓrvinen-Seppo will lead—will extend the longitudinal birth cohort study of OOM and Rochester city children to assess differences between the groups and test various hypotheses.

The project will examine three separate areas where these differences manifest: the immune system, the gut microbiome, and the skin barrier function. The study will be a multi-institutional collaboration: investigators at the Icahn School of Medicine at Mount Sinai, New York, will analyze the role of the gut microbiome in protection from allergic sensitization by utilizing genetic sequencing to assess infant gut microbiome composition and corresponding metabolome. They will also assess the skin microbiome, barrier function and immune environment.

“The infant gut microbiome was drastically different in OOM populations than in Rochester infants and toddlers. OOM infants breastfeed longer and their community is exposed to farm animals, unpasteurized milk and well water, so that could be a factor,” said Jӓrvinen-Seppo.

Jӓrvinen-Seppo’s team at URMC will recruit and follow the cohorts and collect the samples into biorepositories (led by Antti Seppo, PhD, professor of Pediatrics at URMC). They will also study infant immunity by examining blood cells and antibodies, as well as epigenetic mechanisms, to establish potential signature biomarkers that can distinguish between those who develop allergic diseases and those who are protected. Juilee Thakar, PhD, associate professor of Microbiology and Immunology at URMC will lead the biostatistics core.

This project will be supported by the NIAID Asthma and Allergic Diseases Cooperative Research Centers (AADCRC) program. Established five decades ago as the first targeted research program in the field of asthma and allergic diseases, AADCRC is the cornerstone of NIAID's efforts to promote innovative, multidisciplinary clinical and basic research. Supported by a multi-project U19 mechanism, the program aims to leverage expertise provided by centers around the U.S. through collaborations among researchers. The NIAID program currently supports 11 AADCRC research centers; URMC is designated as one of these centers for the first time.