The Charles H. Hood Foundation has awarded MCB Assistant Professor Kazuki Nagashima a Child Health Research Award, supporting his investigation into a fundamental—but poorly understood—process that may hold the key to preventing food allergies in children: how young immune systems learn to tolerate common foods.
Nagashima, who joined Harvard’s Department of Molecular and Cellular Biology in 2024, is known for his innovative approaches to gut immunology. The newly funded project will build on recent discoveries from his lab that hint at an underexplored arm of the immune system’s interaction with diet—namely, the suppressive immune responses mediated by regulatory T cells (Tregs), which are essential for maintaining tolerance to food antigens.
“Food allergy is usually viewed as an overactive immune response,” Nagashima explains. “But we know much less about the suppressive side—how the immune system learns to tolerate food. That’s the part we want to understand better.”
His proposal, which won him the Child Health Research Award, focuses on that part of the immune system that protects against food allergies, rather than causes them. “Inflammatory T cell responses to food are well studied—but the suppressive, tolerogenic response is just as important,” he adds.
A Silent Epidemic—and a Scientific Gap
Food allergies are on the rise among children, leading to increased risk of life-threatening reactions like anaphylaxis and chronic disruptions to growth, education, and mental health. Yet scientists still don’t know which dietary molecules are responsible for educating the immune system during early life—a process known as oral tolerance.
Nagashima’s team is tackling this question head-on by using high-throughput screening approaches to link specific T cell receptors (TCRs) in the gut to food-derived antigens that stimulate protective responses. This approach identified a surprising population of gut-resistant T cells that responded not to bacterial antigens but to unknown dietary antigens, and often exhibited an inflammation-suppressing phenotype.
“We’re trying to identify which food components generate regulatory T cells—and which ones don’t,” he said. “If we can define this suppressive response in early life, it could lead to diet-based strategies to prevent food allergies before they start.”
From Discovery to Prevention
Nagashima’s approach stems from earlier work published in Nature (2023), in which he and collaborators characterized food-responsive TCRs in the mouse intestine. They found that these receptors—many of which are “orphan” TCRs unlinked to known food antigens—exhibited distinct regulatory phenotypes, suggesting that previously unrecognized dietary cues may actively shape the gut immune system.
The new project is an effort to move from observation to mechanism—and ultimately to intervention.
“The long-term goal,” he said, “is to provide a molecular framework for early-life dietary interventions that reduce the risk of food allergies. If we can identify the right components, we may be able to design childhood diets that support immune education and resilience.”
The Charles H. Hood Foundation Child Health Research Awards offer crucial early-career support to investigators across New England, enabling young labs to launch high-risk, high-reward projects in pediatric health. Each award includes $200,000 in research funding over a two-year period.
The $200,000 award will support Nagashima’s pioneering work that explores the idea that certain food-derived antigens—especially proteins commonly found in childhood diets—might trigger the development of protective, rather than harmful, immune responses.
