The Gut Microbiota–Mast Cell Axis in Intestinal Homeostasis and Food Allergy Pathogenesis

Food allergy is an increasing global health burden, particularly in industrialized countries, with rising prevalence in both pediatric and adult populations. It is characterized by exaggerated immune responses to innocuous dietary antigens, leading to clinical manifestations ranging from mild gastrointestinal symptoms to life-threatening anaphylaxis. Mast cells are central effectors in the pathophysiology of food allergy, initiating and amplifying allergic inflammation through the release of a broad array of mediators upon activation. Recent studies have revealed that the intestinal microbiota plays a critical role in shaping immune responses, including the regulation of mast cell development, maturation, and activation. Moreover, dysbiosis has been associated with increased susceptibility to allergic sensitization and heightened mast cell reactivity. This review explores the molecular mechanisms underlying the microbiota–mast cell axis in the context of intestinal homeostasis and food allergy with a particular emphasis on the regulation of mast cell effector functions by TLR signaling and microbial metabolites. We also discuss the therapeutic potential of targeting the microbiota–mast cell axis as novel strategies to restore immune tolerance. Understanding this complex crosstalk opens new avenues for translational approaches in the prevention and treatment of food allergy.