IL-1 is a name that designates two pleiotropic cytokines, IL-1α (IL-1F1) and IL-1β (IL-1F2), which are the products of distinct genes. IL-1α and IL-1β are structurally related polypeptides that share approximately 21% amino acid (aa) identity in human. Both proteins are produced by a wide variety of cells in response to inflammatory agents, infections, or microbial endotoxins.
Specifications and Use of R&D IL-1 beta / IL-1F2
• A DNA sequence encoding the mature human IL-1β protein (Ala 117 - Thr 269; Accession # NP_000567) was expressed in E. coli.
• The 153 amino acid residue recombinant protein has a predicted molecular mass of approximately 17 kDa. The 154 amino acid residue methionyl form may also be present in the preparation.
Purity of R&D IL-1 beta / IL-1F2
• > 97%, as determined by SDS-PAGE and visualized by silver stain.
• < 1.0 EU per 1 μg of the cytokine as determined by the LAL method.
• Measured in a cell proliferation assay using the murine helper T cell line, D10.G4.1 (Symons, J.A. et al., Lymphokines and Interferons, a Practical Approach, 1987, M.J. Clemens, A.G. Morris, and A.J.H.
Gearing, eds., IRL Press, p. 272).
• The ED50 for this effect is typically < 12 pg/mL.
• Lyophilized from a 0.2 μm filtered solution in PBS containing 50 μg of bovine serum albumin per 1 μg of cytokine.
Reconstitution of R&D IL-1 beta / IL-1F2
• It is recommended that sterile phosphate-buffered saline containing at least 0.1% human serum albumin or bovine serum albumin be added to the vial to prepare a stock solution of no less than 10 μg/mL of the cytokine.
Storage of R&D IL-1 beta / IL-1F2
• Lyophilized samples are stable for up to twelve months from date of receipt at -20° C to -70° C.
• Upon reconstitution, this cytokine can be stored under sterile conditions at 2° - 8° C for one month or at -20° C to -70° C in a manual defrost freezer for three months without detectable loss of activity.
• Avoid repeated freeze-thaw cycles.