>98% Pure active Human Recombinant IL-2 Receptor α.
Determined by its ability to increase the proliferation effect of IL-2 in mouse CTLL-2 cells. In the presence of 1 ng/ml of recombinant IL-2, the expected ED50 for this effect is between 0.5-1.5 μg/ml.
The IL-2 receptor system consists of three non-covalently linked subunits termed IL-2Rα, IL-2Rβ, and IL-2Rγ. The IL-2Rα is a type I transmembrane protein consisting of a 219 amino acid extracellular domain, a 19 amino acid transmembrane domain and a 13 amino acid intracellular domain, which is not involved in the transduction of IL-2 signals. Proteolytic processing of IL-2Rα releases the entire extracellular domain of IL-2Rα thereby generating a 219 amino acid soluble protein called soluble IL-2Rα (sIL-2Rα). The homodimeric form binds IL-2 (KD=10mM) and facilitates IL-2 signaling. The secreted sIL-2Rα is expressed on leukemia cells, lymphoma cells, newly activated T and B cells, as well as on approximately 10% of NK cells. Recombinant human sIL-2Rα is a 24.8 kDa protein containing 219 amino acid residues consisting of only the extracellular domain of IL-2Rα. Due to glycosylation, IL-2Rα has an approximate molecular weight of 31 kDa based on SDSPAGE gel and Mass Spectrometry.