Onyinye Iweala, MD, Ph.D., assistant professor in the division of rheumatology, allergy, and immunology, and Wesley Burks, MD, Dean of the School of Medicine and CEO of UNC Health, published a review of a recent study looking at how IgE-producing B cells in the gut expand the gut’s role in food allergy.
CHAPEL HILL, NC – In a review published in Nature Reviews Gastroenterology & Hepatology, Onyinye Iweala, MD, PhD, and Wesley Burks, MD, examine the significance of a study in patients with peanut allergies that finds IgE-producing B cells are present in the gut.“Before this study, it was believed that long-term allergic antibody responses were probably driven by IgE-producing B cells clustered in the bone marrow. But this didn’t completely make sense for food allergies,” Iweala said. “When you eat something like peanuts, it goes to your gut, not your bone marrow. Identifying these IgE-producing B cells in the gut is a step forward in better understanding and treating food allergies, and possibly all allergies.”
The journal Nature Reviews Gastroenterology and Hepatology requested that Iweala and Burks complete this review article of the study, “Origins and clonal convergence of gastrointestinal IgE+ B cells in human peanut allergy,” originally published in Science Immunology. The study delves into the origins of IgE antibody-producing B cells in the gastrointestinal tract and its associated lymphoid tissues, since these tissues are frequently exposed to different foods, including peanut. By studying the guts of 19 peanut-allergic patients, the study’s authors concluded that local antibody isotype switching is occurring in the gut between IgA, IgG and IgE isotypes. The study results also confirm the existence of food-specific IgA in the gastrointestinal tract, in addition to the IgA specific for the commensal gut microbiota. But the interactions between food- and microbial-specific IgA B-cell clones still need to be explored.
“This leads us to question – if you impact the microbiome, do you have an effect on the allergenic food-specific B cells?” posed Iweala. “Can we change the micro environment by targeting that area with chemical signals to make food-specific B cells produce other antibodies besides IgE?”
Iweala says this was a small and narrowly focused study on patients with peanut allergies, so many questions remain as to its significance in other food or non-food allergies. But, she says the study’s authors have added another piece to the puzzle of where IgE-producing cells reside. With this new knowledge, there is potential to enhance current diagnostic and prognostic markers for food allergy and to develop targeted tissue-specific therapies for conventional food allergies and beyond.