• Purity

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

• Endotoxin Level

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

• Activity

  Measured by its ability to chemoattract BaF3 mouse pro?B cells transfected with human CXCR2. The ED    ₅₀ for this effect is 2-10 ng/mL.

• Source

  E. coli-derived Ala23-Ala101

• Accession #

• N-terminal Sequence    
  Analysis

  Ala23

• Predicted Molecular Mass

  9 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-8/CXCL8

Interleukin-8 (IL-8), also known as CXCL8, GCP-1, and NAP-1, is a widely expressed proinflammatory member of the CXC family of chemokines. Near its N-terminus, this 8-9 kDa chemokine contains an ELR motif which is important for its angiogenic properties (1). CXCL8 can associate into a homodimer or a heterodimer with CXCL4/PF4 (2), and it can also interact with matrix and cell surface glycosaminoglycans (3). Mature feline CXCL8 shares 87%, 68%, and 78% amino acid (aa) sequence identiity with canine, human, and porcine CXCL8 (4). There is no CXCL8 gene counterpart in rodent. N-terminal truncation of CXCL8 by multiple proteases generates a range of shorter forms (5). The bioactivity of CXCL8 is regulated by these truncations, by CXCL8 citrullination at Arg5 (N-terminal to the ELR motif) (6), and by the decoy receptor DARC (7). CXCL8 effects are mediated through CXCR1/IL-8 RA, which is also used by CXCL6, and through CXCR2/IL-8 RB, which is used by multiple CXC chemokines (1). These receptors associate into functional homodimers and heterodimers with each other (8). Through both CXCR1 and CXCR2, CXCL8 promotes neutrophil adhesion to the vascular endothelium and migration to sites of inflammation (9). It triggers the antimicrobial activation of neutrophils through CXCR1 (10). CXCL8 also binds to Serpin A1/alpha-1 Antitrypsin, and this prevents CXCL8 interaction with CXCR1 (11). CXCL8 is upregulated in atherosclerotic lesions and other cardiac pathologies where it exacerbates inflammatory tissue damage (12). In addition, it induces VEGF expression, vascular endothelial cell proliferation, angiogenesis, and tumor cell invasiveness (13-16).

• References:

1. Lazennec, G. and A. Richmond (2010) Trends Mol. Med. 16:133.

2. Nesmelova, I.V. et al. (2005) J. Biol. Chem. 280:4948.

3. Pichert, A. et al. (2012) Biomatter 2:142.

4. Schmid, J. and C. Weissmann (1987) J. Immunol. 139:250.

5. Mortier, A. et al. (2008) Pharmacol. Ther. 120:197.

6. Proost, P. et al. (2008) J. Exp. Med. 205:2085.

7. Neote, K. et al. (1994) Blood 84:44.

8. Munoz, L.M. et al. (2009) J. Immunol. 183:7337.

9. Gerszten, R.E. et al. (1999) Nature 398:718.

10. Jones, S.A. et al. (1996) Proc. Natl. Acad. Sci. USA 93:6682.

11. Bergin, D.A. et al. (2010) J. Clin. Invest. 120:4236.

12. Apostolakis, S. et al. (2009) Cardiovasc. Res. 84:353.

13. Martin, D. et al. (2009) J. Biol. Chem. 284:6038.

14. Li, A. et al. (2005) Angiogenesis 8:63.

15. Waugh, D.J. and C. Wilson (2008) Clin. Cancer Res. 14:6735.

16. Fernando, R.I. et al. (2011) Cancer Res. 71:5296.

• Long Name:

  Interleukin 8

• Entrez Gene IDs:

  3576 (Human); 396880 (Porcine); 403850 (Canine); 493836 (Feline)

• Alternate Names:

  3-10C; AMCF-I; C-X-C motif chemokine 8; CXCL8; CXCL8SCYB8; Emoctakin; GCP1; GCP-1TSG-1; IL8; IL-8; interleukin 8; K60; LAI; LECT; MDNCF; MDNCFb-ENAP; member 8; MONAPGCP1; NAP1; NAP-1NAP1; NCF; Neutrophil-activating protein 1; Protein 3-10C; T cell chemotactic factor; T-cell chemotactic factor; TCF; TSG1