IL-1RA-5

Equine

E.coli

Recombinant Equine IL-1RA
IL-1RN, IRAP

Secreted equine IL-1 receptor antagonist (IL-1ra) is a presumably 22-25 kDa glycoprotein produced by variety of cell types that antagonizes IL-1 activity. It is a member of the IL-1 family of proteins that includes IL-1 alpha and IL-1 beta. Although there is little amino acid (aa) identity (< 30%) among the three IL-1 family members, all molecules bind to the same receptors, all show a beta -trefoil structure, and all are believed to have evolved from a common ancestral gene. Equine IL-1ra is synthesized as a 177 aa precursor that contains a 25 aa signal sequence plus a 152 aa mature region. There is one intrachain disulfide bond and one potential N-linked glycosylation site. Mature equine sIL-1ra is 78%, 78%, 80%, 82%, and 76% aa identical to mature mouse, human, porcine, canine and bovine IL-1ra, respectively. In human, three non-secreted IL-1ra isoforms have also been identified. It is unknown if such an analogous situation exists in equine. Cells known to secrete IL-1ra include fibroblasts, vascular smooth muscle cells, intestinal columnar epithelium, chondrocytes, macrophages, mast cells, neutrophils and hepatocytes. There are two type I transmembrane glycoprotein receptors for IL-1ra. The first is the bioactive 80 kDa type I IL-1 receptor (IL-1 RI), and the second is the inert (decoy) 65 kDa type II IL-1 receptor. IL-1ra binding to IL-1 RI competitively blocks IL-1 ( alpha or beta ) binding to the same receptor. This results in receptor ligation without activation. The type II IL-1 receptor is inert, and any binding of IL-1ra not only fails to block co-existing IL-1 activity, but may actually potentiate it by removing an IL-1 antagonist. Functionally, all activities attributed to IL-1ra are explained by its role as a competitive inhibitor of IL-1 binding to IL-1 RI.

Approximately 17.4 kDa.

HPLGKRPCKM QAFRIWDVNQ KTFYMRNNQL VAGYLQESNT KLQEKIDVVP IEPDALFLGL HGRKLCLACV KSGDEIRFQL EAVNITDLSK NKEENKRFTF IRSNSGPTTS FESAACPGWF LCTAQEADRP VSLTNKPKES FMVTKFYLQE DQ

Sterile Filtered White lyophilized (freeze-dried) powder.

> 95% by SDS-PAGE and HPLC analyses.

The ED50 as determined by inhibiting IL-1α-dependent proliferation of murine D10S cells is less than 3.0 μg/mL, corresponding to a specific activity of > 333 IU/mg in the presence of 50 pg/mL rHuIL-1α. Fully biologically active when compared to standard.

< 1.0 EU per 1μg of the protein by the LAL method.

Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH 7.4.

We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20°C. Further dilutions should be made in appropriate buffered solutions.

5, 100, 500μg