A groundbreaking study published in Science Translational Medicine suggests that "poop pills," a form of fecal transplant, may offer a novel treatment for severe peanut allergies. The research found that individuals who received a fecal transplant from donors without food allergies exhibited a heightened tolerance to peanuts months later.
This approach builds upon previous research where stool samples transferred from infants with food allergies to allergy-prone mice induced severe allergic reactions. Conversely, mice that received samples from healthy infants were protected against these reactions. Researchers identified beneficial bacterial strains from the healthy infants' gut microbiomes and encapsulated them into frozen "poop pills."
In the recent study, 10 young adults with severe peanut allergies underwent a one-time treatment, taking 36 pills over several hours. After a four-month follow-up period, three participants were able to consume multiple peanuts before experiencing an allergic reaction. A subsequent phase of the study incorporated antibiotics into the fecal transplant pills, which appeared to further enhance the effectiveness of the microbiome transfer.
The fecal transplants worked by increasing the production of bile salts, which aid in fat digestion and absorption. It is believed that beneficial gut bacteria play a role in metabolizing these bile salts, subsequently increasing immune-regulating cells that protect against allergic responses.
"Food allergy reflects a failure of oral tolerance, the process by which the gut immune system learns to accept food," said Talal Chatila, director of translational immunology at Boston Children's Hospital and one of the study's lead researchers, in a press release. "What this study shows is that the right bacteria can help restore that process, working through bile acid metabolites to promote the immune cells that enforce tolerance."
While these findings are promising, the researchers are developing a modified version of the pills using a purified and concentrated form of microbes that can be stored in a refrigerator for easier access. Larger studies are also planned to confirm the results, identify patient subgroups most likely to benefit, and discover additional beneficial bacteria for potential probiotic treatments for food allergies. Up to 6 million people in the United States have allergic reactions to peanuts, making it one of the most common food allergies.