IL-5 receptor alpha

Class

Anti-IL-5Ralpha monoclonal antibody

Interleukin-5 receptor alpha (IL-5Rα) is a cell-surface protein found predominantly on eosinophils and, to a lesser extent, basophils. It forms part of the receptor complex for interleukin-5 (IL-5), a cytokine that drives the growth, maturation, activation, and survival of eosinophils, a type of white blood cell involved in allergic and parasitic immune responses. In several chronic inflammatory diseases, eosinophils accumulate in tissues such as the airways and contribute to inflammation, tissue damage, and symptom severity. Monoclonal antibodies directed against IL-5Rα bind directly to the receptor on eosinophils rather than to the circulating cytokine itself. This approach not only blocks IL-5 from signaling through its receptor but also flags the eosinophil for destruction by other immune cells, leading to a more thorough depletion of eosinophils from blood and tissue than simply neutralizing the cytokine. This mechanism is broadly relevant to eosinophil-driven diseases, including severe asthma with an eosinophilic component and other hypereosinophilic conditions, where reducing eosinophil numbers can lessen inflammation and improve disease control. The receptor-targeting strategy represents one of several ways pharmacology has approached interrupting the IL-5 signaling axis.