Il5ra, also known as interleukin-5 receptor subunit alpha, is known to regulate the development and function of eosinophils. This protein is a therapeutic target for hypereosinophilic diseases including allergic inflammations and asthma. Oct2 enhances antibody-secreting cell differentiation through regulation of IL-5 receptor alpha chain expression on activated B cells. Recombinant mouse Il5ra, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.