• Purity

  >97%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <0.01 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to inhibit IL-36 alpha, IL-36 beta or IL-36 gamma -induced IL-6 secretion by NIH‑3T3 mouse embryonic fibroblast cells. The ED    ₅₀ for this effect is 0.8-4 μg/mL in the presence of 15 ng/mL of recombinant mouse IL-36 beta (aa 31‑83). Measured by its binding ability in a functional ELISA. Immobilized Recombinant Mouse IL-36Ra/IL-1F5 at 1 µg/mL (100 µL/well) can bind Recombinant Human IL-1 Rrp2/IL-1 R6 Fc Chimera(Catalog # ) with a linear range of 0.15-5 µg/mL.

• Source

  E. coli-derived Val2-Asp156

• Accession #

• N-terminal Sequence    
  Analysis

  Val2

• Predicted Molecular Mass

  17 kDa

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-36Ra/IL-1F5

Mouse interleukin-36 receptor antagonist (IL-36Ra; previously IL-1F5; also named FIL-1δ [delta], IL‑1HY1, IL-1H3, and IL-1L1) is a member of the IL‑1 family of proteins (1-6). IL‑1 family members include IL-1 beta, IL-1 alpha, IL-1ra, IL‑18 and IL‑1F5 through F10 (6, 7). All family members show a 12 beta -strand, beta -trefoil configuration, and are believed to have arisen from a common ancestral gene that underwent multiple duplications (8). The mouse IL‑36Ra/IL‑1F5 gene maps to a region on mouse chromosome 2 that contains all other IL-1 family members (except IL‑18), supporting an evolutionary relationship with the IL-1 family (1, 9). It is particularly close to the gene for IL-1ra and is likely a relatively recent duplication of that gene. IL‑36Ra/IL‑1F5 is synthesized as a 156 amino acid (aa) protein that contains no signal sequence, no prosegment and no potential N-linked glycosylation site(s) (2, 5, 8). Nevertheless, it appears to be secreted as a 17 kDa monomer. In humans, there is an alternate start site that potentially gives rise to an alternate splice form (5). This translated product has a premature stop codon, resulting in a truncated 16 aa peptide. Mouse to human, full length IL‑36Ra/IL‑1F5 has 90% aa identity. Within the family, IL-36Ra/IL-1F5 is 48%, 30%, 35%, 35%, 35%, 37% and 43% aa identical to IL‑1ra, IL‑1 beta, IL‑36 alpha /IL‑1F6, IL‑37/IL‑1F7, IL-36 beta /IL-1F8, IL‑36 gamma /IL‑1F9 and IL‑1F10, respectively. Cells reported to express IL-36Ra/IL-1F5 include monocytes, B cells, dendritic cells/Langerhans cells, keratinocytes, and gastric fundus Parietal and Chief cells (1, 8). The receptor for IL-36Ra/IL-1F5 has not been positively identified. Indirect evidence suggests it is IL‑1 Rrp2 and/or IL-1 RAcP (9). In either case, activity association with receptor binding is unclear. It was initially reported to be an antagonist of  IL-36 gamma activity (4, 7). This would be consistent with its hypothesized relationship to IL‑1ra.

• References:

1. Smith, D. E. et al. (2000) J. Biol. Chem. 275:1169.

2. Kumar, S. et al. (2000) J. Biol. Chem. 275:10308.

3. Mulero, J.J. et al. (1999) Biochem. Biophys. Res. Commun. 263:702.

4. Nicklin, M.J.H. et al. (2002) Genomics. 79:718.

5. Barton J. L. et al. (2000) Eur. J. Immunol. 30:3299.

6. Dinarello, C. et al. (2010) Nat. Immunol. 11:973.

7. Dunn, E. et al. (2001) Trends Immunol. 22:533.

8. Debets, R. et al. (2001) J. Immunol. 167:1440.

9. Towne, J.E. et al. (2004) J. Biol. Chem. 279:13677.

• Long Name:

  Interleukin 36 Receptor Antagonist/Interleukin 1 Family 5

• Entrez Gene IDs:

  26525 (Human); 54450 (Mouse)

• Alternate Names:

  FIL1 delta; IL1F5; IL-1HY1; IL-1L1; IL-1RP3; IL36Ra; IL-36Ra; IL36RN; Interleukin 36 Receptor Antagonist; Interleukin-36 Receptor Antagonist