Aberrant Activation of Mast Cells: Molecular Mechanisms and Targets for Intervention.

Mast cells play a key role in innate immunity by mediating host defense and maintaining tissue balance. They achieve this through the controlled release of bioactive mediators such as histamine, heparin, leukotrienes, and prostaglandin D2. Their functional diversity is enabled by multiple receptor systems that coordinate differentiation, maturation, and degranulation processes through tissue-specific microenvironmental signals. Pathological activation through allergen exposure or intrinsic regulatory dysfunction contributes to various disorders, ranging from allergic conditions to autoimmune diseases and chronic inflammatory states. Current anti-mast cell therapies have expanded from broad-spectrum antihistamines to more precise treatments targeting IgE or its surface receptors expressed on mast cells. Emerging insights into activation mechanisms of mast cells, particularly structural and functional characterization of critical receptors, have accelerated the development of novel therapeutic interventions. This review discusses the advances in molecular mechanisms of mast cell activation and summarizes how these findings redefine our understanding of disease progression and emerging therapeutic targets.