Interleukin-4 receptor (IL-4R)

The **Interleukin‑4 pathway** refers primarily to the signaling events initiated by binding of the cytokine interleukin 4 (IL‑4) to its specific cell surface receptors. The canonical target is the **interleukin 4 receptor**—a type I cytokine receptor composed either as a type I complex (IL‑4Rα plus common gamma chain) on hematopoietic cells or a type II complex (IL‑4Rα plus IL13Rα1) on nonhematopoietic cells. Engagement triggers intracellular cascades involving JAK/STAT pathways—most notably STAT6—which drive differentiation toward T helper 2 phenotypes, promote IgE class switching in B lymphocytes, enhance mast cell survival/proliferation, and contribute centrally to allergic inflammation and asthma pathogenesis. Overexpression or dysregulation is implicated in various diseases including allergy/asthma, certain cancers such as head and neck carcinoma where it may serve as a therapeutic target for antibody-based drugs like dupilumab or experimental toxin conjugates. Note: The query "Interleukin‐⁠⁠⁠⁠⁠⁠⁴ pathway" describes a biological process rather than a single molecular entity; however, drug targeting focuses almost exclusively on components like **interleukin ⁴ itself** or more commonly its primary functional mediator—the **interleukin ⁴ receptor**. Thus this entry standardizes information around "Interleukin‐⁴ receptor" per conventions above.

Other names

IL-4 receptorIL4RInterleukin 4 receptor alpha (IL-4Rα)CD124

Antagonism or blockade of the interleukin‑4 signaling pathway by binding to the IL‑4 receptor alpha subunit, inhibiting downstream STAT6 activation and Th2-mediated responses. Targeted cytotoxicity via fusion proteins that deliver toxins specifically to cells expressing high levels of IL‑4 receptors