Microbiota Therapy Acts Via a Regulatory T Cell MyD88/ROR-gamma t Pathway to Suppress Food Allergy

Food allergy (FA) is a major public health concern, whose prevalence has grown dramatically over the past decade. FA now affects 6% of children under 5 years, and 3% of teens and adults. The role of dysbiosis in food allergy (FA) remains unclear. We tested the hypothesis that food allergy early in life is associated with gut microbial dysbiosis by analyzing the fecal microbiota of food allergic (FA) and age matched control infants recruited at 1-15 months of age and periodically sampled every 4-6 months for up to 30 months of age. The fecal microbiota was assessed via high-throughput sequencing of 16S rRNA gene amplicons (V4) regions. We found that dysbiotic fecal microbiota in FA infants evolved compositionally over time, and failed to protect against FA in mice. Therapy with Clostridiales species reflective of taxa impacted by dysbiosis, either as a small consortium or as monotherapy , suppressed FA in mice, as did a separate immunomodulatory consortium of Bacteroidales species.