Recent insights into the mechanisms of anaphylaxis

Anaphylaxis is an acute life-threatening systemic allergic reaction that can have a wide range of clinical manifestations. The most common triggers for anaphylaxis include food, medication, and venom. What is curious regarding anaphylaxis is how so many different agents can induce a severe systemic clinical response but only in a select subgroup of patients. Over the past decade, several important advances have been made in understanding the underlying cellular and molecular mechanisms contributing to anaphylaxis, with mast cells (MCs) being an essential component. Classically, cross-linked immunoglobulin E (IgE) bound to its high- affinity receptor induces MC mediator release. However, toll-like, complement, or Mas-related G-protein-coupled receptors also activate mouse and human MCs. While anaphylaxis secondary to foods historically has been more extensively characterized clinically and mechanistically, more recent studies have shifted focus toward understanding drug-induced anaphylaxis. The focus of this review is to highlight recent basic science developments and compare what is currently known regarding anaphylaxis to food, medications, and venom.