• Purity

  >90%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie? Blue Staining.

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to inhibit M1 mouse myeloid leukemia cell proliferation. The ED    ₅₀ for this effect is 2.5-12.5 ng/mL.

• Source

  Human embryonic kidney cell, HEK293-derived

  Human IL-6 R alpha (Leu20-Asp358) Accession # P08887	GGGSGGGSGGGS	Human IL-6 Val30-Met212 Accession # P05231
  N-terminus		C-terminus

• N-terminal Sequence    
  Analysis

  Leu20 (Human IL-6R alpha)    
   

• Predicted Molecular Mass

  59 kDa

• SDS-PAGE

  78-93 kDa, reducing conditions    
   

Carrier Free

What does CF mean?

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

What formulation is right for me?

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: IL-6 R alpha

Interleukin-6 (IL-6) is a pleiotropic, alpha -helical, 22-28 kDa phosphorylated and variably glycosylated cytokine that plays important roles in the acute phase reaction, inflammation, hematopoiesis, bone metabolism, and cancer progression (1-5). Mature human IL-6 is 183 amino acids (aa) in length and shares 39% aa sequence identity with mouse and rat IL-6 (6). Alternative splicing generates several isoforms with internal deletions, some of which exhibit antagonistic properties (7-10). IL-6 induces signaling through a cell surface heterodimeric receptor complex composed of a ligand binding subunit (IL-6 R alpha) and a signal transducing subunit (gp130). IL-6 binds to IL-6 R alpha, triggering IL-6 R alpha association with gp130 and gp130 dimerization (11). gp130 is also a component of the receptors for CLC, CNTF, CT-1, IL-11, IL-27, LIF, and OSM (12). Soluble forms of IL-6 R alpha are generated by both alternative splicing and proteolytic cleavage (5). In a mechanism known as trans-signaling, complexes of soluble IL-6 and IL-6 R alpha elicit responses from gp130-expressing cells that lack cell surface IL-6 R alpha (5). Trans-signaling enables a wider range of cell types to respond to IL-6, as the expression of gp130 is ubiquitous, while that of IL-6 R alpha is predominantly restricted to hepatocytes, monocytes, and resting lymphocytes (2, 5). Soluble splice forms of gp130 block trans-signaling from IL-6/IL-6 R alpha but not from other cytokines that use gp130 as a co-receptor (5, 13). IL-6, along with TNF-alpha and IL-1, drives the acute inflammatory response and the transition from acute inflammation to either acquired immunity or chronic inflammatory disease (1-5). When dysregulated, it contributes to chronic inflammation in obesity, insulin resistance, inflammatory bowel disease, arthritis, sepsis, and atherosclerosis (1, 2, 5). IL-6 can also function as an anti-inflammatory molecule, as in skeletal muscle where it is secreted in response to exercise (2). In addition, it enhances hematopoietic stem cell proliferation and the differentiation of Th17 cells, memory B cells, and plasma cells (1, 14).

• References:

1. Mansell, A. and B.J. Jenkins (2013) Cytokine Growth Factor Rev. 24:249.

2. Schuett, H. et al. (2009) Thromb. Haemost. 102:215.

3. Erta, M. et al. (2012) Int. J. Biol. Sci. 8:1254.

4. Garbers, C. et al. (2012) Cytokine Growth Factor Rev. 23:85.

5. Mihara, M. et al. (2012) Clin. Sci. (Lond.) 122:143.

6. Hirano, T. et al. (1986) Nature 324:73.

7. Kestler, D.P. et al. (1995) Blood 86:4559.

8. Kestler, D.P. et al. (1999) Am. J. Hematol. 61:169.

9. Bihl, M.P. et al. (2002) Am. J. Respir. Cell Mol. Biol. 27:48.

10. Alberti, L. et al. (2005) Cancer Res. 65:2.

11. Murakami, M. et al. (1993) Science 260:1808.

12. Muller-Newen, G. (2003) Sci. STKE 2003:PE40.

13. Mitsuyama, K. et al. (2006) Clin. Exp. Immunol. 143:125.

14. Cerutti, A. et al. (1998) J. Immunol. 160:2145.

• Long Name:

  Interleukin 6 Receptor alpha

• Entrez Gene IDs:

  3570 (Human); 16194 (Mouse)

• Alternate Names:

  CD126; IL-6 R alpha; IL6R alpha; IL6R; IL-6Ra