Scientists from Boston Children's Hospital and Brigham and Women's Hospital suggested in their new study that food allergy is caused by the absence of certain beneficial gut bacteria. Dr. Talal Chatila, the director of the Food Allergy Program at the hospital and the senior author of the paper, said that the loss of these bacteria makes children susceptible to food allergies.
The study conducted on mice also points toward a treatment that may help protect children from food allergies by reversing the disease, EurekAlert! reported. Study co-senior author Dr. Rima Rachid, assistant director of the Food Allergy Program in the hospital, said they hope their study would lead to treatment rather than just a preventative approach.
Good Bacteria Could Prevent Food Allergy
Some scientists suggest that certain Western lifestyle factors, like the increased Caesarean section births, increased use of antibiotics, the decline in breastfeeding, and smaller family size, may have raised chances of developing a food allergy as it disrupts the normal balance in the gut and deprive the child of the good bacteria that prepare the immune system to recognize some food to be harmless.
Science News reported that researchers conducted a small clinical trial in which those with food allergies were given fecal transplant pills for one day and were asked to consume one or more peanuts. The pills help some of them, which signals a step toward seeing whether it could extend to people who do not have a peanut allergy.
In a 2019 study, Rachid and her colleagues found that certain bacteria were enriched in the stool of babies without food allergies compared to those who have. When they transferred it to allergy-prone mice, it prevented the allergic reaction and showed that the treatment activated a subset of immune cells called regulatory T-cells that protected the mice from allergic responses.
Fecal microbiota transplants in humans involve taking feces from healthy people and transplanting it into ill people, usually through colonoscopy. FMTs are usually applied to those with recurrent Clostridium difficile infections. Through this research, the team was able to show that fecal material is also effective in the form of oral capsules to treat a food allergy.
Testing FMT to Other Types of Food Allergy
The results of phase 1 of the clinical trial were presented during the annual meeting of the American Academy of Allergy, Asthma & Immunology (AAAAI) in Phoenix, USA, in late February. The clinical trial is the first to test the effectiveness of fecal transplantation in those who have food allergies.
According to Allergic Living, participants consumed 36 stool capsules within three hours in which each dose of FMT is about the same dose given to treat C. difficile infection. But only one dose was given to the participants during the clinical trial. The team did not test how many doses are needed to maintain long-term protection.
They partnered with scientists from nonprofit stool bank OpenBiome and asked participants who would be donating fecal samples to avoid peanuts and tree nuts for a week. Researchers also noted that there was no serious adverse reactions during the clinical trial.
When they tested FMT to egg allergy-prone mice, they also were protected from anaphylaxis when they ate an egg. On the other hand, the mice that got a stool from participants who did not respond also did not have the protection.
Laboratory tests showed that those who positively responded to FMT increased in regulatory T-cells that are linked to immune tolerance and had decreased number of T helper cells associated with allergy, showing a therapeutic response to FMT.
RELATED ARTICLE: Peanut Allergy Solution: Two New Effective Treatments That Significantly Increase Children's Quality of Life Discovered
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