IL-6 mediates its biological effects through the type I IL-6 receptor system that consists of two chains, IL-6Ralpha and gp130. While the IL-6Ralpha chain is the binding component specific to IL-6, the gp130 chain only transmits signals of IL-6 when bound to IL-6Ralpha. The gp130 can also transmit signals from LIF, OSM, CNTF, IL-11 and CT-1 in conjunction with other receptor subunits. The low-affinity binding site for IL-6 is composed of IL-6Ralpha alone. IL-6Ralpha is expressed in a wide range of cells, including T cells, fibroblasts and macrophages. Soluble IL-6Ralpha, which consists of only the extracellular domain of the IL-6Ralpha chain, acts as an agonist of IL-6 activity at low concentrations. CHO cell-derived Recombinant Human sIL-6 Receptor alpha is a 37.9kD glycoprotein corresponding to 339 amino acid residues of the extracellular domain of IL-6Ralpha. As a result of glycosylation, Recombinant Human sIL-6 Receptor alpha migrates with an apparent molecular mass of approximately 57-70kD by SDS-PAGE gel, under reducing conditions. Biological Activity: Determined by its ability to intensify the IL-6 induced growth inhibition of mouse M1 cells. The expected ED50 is 5ng/ml, in the presence of 20ng/ml of rhIL-6. Amino Acid Sequence: LAPRRCPAQE VARGVLTSLP GDSVTLTCPG VEPEDNATVH WVLRKPAAGS HPSRWAGMGR RLLLRSVQLH DSGNYSCYRA GRPAGTVHLL VDVPPEEPQL SCFRKSPLSN VVCEWGPRST PSLTTKAVLL VRKFQNSPAE DFQEPCQYSQ ESQKFSCQLA VPEGDSSFYI VSMCVASSVG SKFSKTQTFQ GCGILQPDPP ANITVTAVAR NPRWLSVTWQ DPHSWNSSFY RLRFELRYRA ERSKTFTTWM VKDLQHHCVI HDAWSGLRHV VQLRAQEEFG QGEWSEWSPE AMGTPWTESR SPPAENEVST PMQALTTNKD DDNILFRDSA NATSLPVQD Storage and Stablility: Lyophilized and reconstituted products are stable for 6 months after receipt at -20C. Reconstitute with sterile PBS. Aliquot to avoid repeated freezing and thawing. Store at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
