Gut Bacteria Could Be Key to Allergy Prevention

In a scientific breakthrough that could change the lives of patients around the world, a new study has identified groups of bacteria in the guts of human infants that protect the immune system against food allergies. Working from Brigham and Women's Hospital and Boston Children's Hospital, the researchers successfully pinpointed biological changes linked to the development of food allergies and the negative immune response associated with certain edibles. They then developed a new microbiome therapy, with the findings published in Nature Medicine.

In the United States, food-related allergic reactions send one person to hospital every three minutes. Until now, the only way to prevent allergic reactions from taking place is to avoid the offending substance. However, this can be difficult when common foods such as peanuts, eggs and shellfish are at fault. The new study seeks to reverse food allergies or prevent them altogether by altering the microbiome, i.e. the complex bionetwork of microorganisms found in the human gut and throughout the body.

Therapy seeks to reset the immune system

Every four to six months the team used computational approaches to analyse faecal samples from more than 50 infants who developed food allergies. They then evaluated samples from almost 100 infants who didn't develop food allergies and found significant differences in microbiota.

"This represents a sea change in our approach to therapeutics for food allergies," explains Lynn Bry, co-senior author of the study and director of the Massachusetts Host-Microbiome Centre at the Brigham. "We've identified the microbes that are associated with protection and ones that are associated with food allergies in patients. If we administer defined consortia representing the protective microbes as a therapeutic, not only can we prevent food allergies from happening, but we can reverse existing food allergies in preclinical models. With these microbes, we are resetting the immune system."

Transplanting protective bacteria

Using the data, the team developed two groups of protective bacteria, each containing five or six species belonging to either the Clostridiales or Bacteroidetes phylum. The groups of protective bacteria were then orally administered to mice with egg allergies. Rodents who received gut bacteria from healthy infants enjoyed greater protection against egg allergies than the rodents who received gut bacteria from infants with food allergies. Furthermore, the team noted the formula could reverse food allergies by boosting tolerance.

Georg Gerber, co-author of the study says, "It's very complicated to look at all of the microbes in the gut and make sense of what they may be doing in food allergy, but by using computational approaches, we were able to narrow in on a specific group of microbes that are associated with a protective effect."

For more insight into the latest scientific developments, don't miss 'Accelerating innovation in virtually all fields of research' which offers commentary from Xia Liu, Mechanical Project Engineer at Diamond Light Source, the UK’s National Synchrotron.