Fecal and metabolome mediators differ in healthy and food-allergic couples, study shows

A new study out of the University of Chicago and Stanford University has identified pairs of couples with and without food allergies, identified microbial players in this condition. The results were released on January 19 in the Journal of Clinical Research.

The study grew out of prior research in Uagicago’s Nagler laboratory on the fecal microbiota in infants. By transmitting fecal microbes from healthy and food-allergic babies to organically free mice (which do not have mosquitoes), researchers found that the healthy baby microbiota was immune to the development of food allergies.

In this study, we looked at a more diverse population across a wide range of ages. By studying twin twins, we had the benefit of studying genetically identical people who grew up in the same environment, which allowed us to begin to elucidate the influence of genetic factors and environmental. “

Cathryn Nagler, PhD, Bunning Family Professor, School of Molecular Engineering, Department of Pathology and College at the University of Chicago Medical Center

After a discussion at a research conference, Nagler and her Stanford colleague Kari Nadeau, MD, PhD, decided to collaborate on the project. Nadeau, Director of the Sean N. Parker Center for Allergy and Asthma Research, had been studying the epigenetics of food allergies and had already collected fecal samples from study participants.

The Nagler lab performed the series on the samples collected from 13 pairs of food allergies with and without food allergies, as well as five additional pairs of pairs where both had at least one food allergy.

The research team looked at what microbes were present in the fecal samples as well as metabolic products (called metabolites), which came not only from the microbes, but also from host and dietary sources.

“We desperately need biomarkers to understand the immunoregulatory action of intestinal bacteria,” Nagler said. “Metabolites tell us what bacteria do mechanically to regulate the immune response.”

This approach identified 64 distinct sets of bacterial species and metabolites that isolated the healthy and allergic twin groups. Most of these abundantly different bacteria were members of the Clostridia class, which has been shown to protect against food allergies in several previous reports from Nagler ‘s laboratory.

The enrichment of the allergic immune bacteria in the healthy twins, established early in life, led to adulthood despite segregation and lifestyle changes. In addition, a healthy pair showed a richness for the diacylglycerol metabolic pathway and two specific bacteria: Phascolarctobacterium faecium and Ruminococccus bromii.

“To narrow down from thousands of bacteria to specific species as candidates for future therapeutic interventions, one measure of data is not enough – combining data from multiple sizes is the key,” she said. first author Riyue Bao, PhD, now Research Professor of Medicine at the University of Pittsburgh. ”In our study, we used the benefits of both high-intensity microbiology sequences and high-profile methods. metabolic, and we were able to identify two specific species, each involved in specific metabolite pathways, which can be prioritized as potential targets for future research and therapeutic interventions. . “

“Tons of people go to Google and they want to know: ‘Should I eat yogurt? Shouldn’t I eat yogurt? Does my midge have a part in my disease?” ” Nadeau said: “This research is important as one of the key ‘bricks’ in the knowledge of human midges that needs to be put down to answer these questions. We cannot say that this is a cause and effect relationship yet, but we can say that there is a relationship between disease and health. So now we can start asking, what does this mean? “

Although the study involved only a small group of participants, researchers are excited about the results and how they can be applied to future projects.

Future research will explore the specific roles of these bacteria in food allergies; for example, R. bromii is a key species in the decline of resistant starch – a dietary starch that usually escapes digestion.

Nagler intends to investigate how supplementation with a starch-resistant starch may affect the presence of R. bromii in the fecal microbiome, and then whether it can increase the response of oral immunotherapy, the same currently available treatments for food allergies.