• Purity

  >95%, 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 in a cell proliferation assay using TF?1 human erythroleukemic cells. Kitamura, T.     et al. (1989) J. Cell Physiol.     140:323. The ED    ₅₀ for this effect is 1.5-6 ng/mL.

• Source

  Mouse myeloma cell line, NS0-derived Ile20-Ser134, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Ile20

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  14 kDa (monomer)

• SDS-PAGE

  18-20 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-5

Interleukin-5 (IL-5) is a secreted glycoprotein that belongs to the alpha -helical group of cytokines (1 ? 3). Unlike other family members, it is present as a covalently linked antiparallel dimer (4, 5). Porcine IL?5 is synthesized as a 134 amino acid (aa) precursor that contains a 19 aa signal sequence and a 115 aa mature segment. Mature porcine IL?5 shares 66%, 63%, 59%, 84%, 85%, 86%, 90% and 88%, aa sequence identity with human, mouse, rat, canine, equine, feline, bovine and ovine IL-5, respectively. IL-5 is primarily produced by CD4⁺ Th2 cells, but also by activated eosinophils, mast cells, EBV-transformed B cells, Reed-Sternberg cells in Hodgkin’s disease, and IL-2-stimulated invariant natural killer T cells (iNKT) (1 ? 3, 6 ? 8). IL-5 increases production and mobilization of eosinophils and CD34⁺ progenitors from the bone marrow and causes maturation of eosinophil precursors outside the bone marrow (1, 6, 9, 10). The receptor for human IL-5, mainly expressed by eosinophils, but also found on basophils and mast cells, consists of a unique ligand-binding subunit (IL-5 R alpha ) and a shared signal-transducing subunit, beta c (3, 6, 11). IL?5 R alpha first binds IL-5 at low affinity, then associates with preformed beta c dimers, forming a high-affinity receptor (12). IL-5 also binds proteoglycans, potentially enhancing its activity (13). Soluble forms of IL-5 R alpha   antagonize IL-5 and can be found in vivo (10, 14). In humans, IL-5 primarily affects cells of the eosinophilic lineage, and promotes their differentiation, maturation, activation, migration and survival, while in mice IL-5 also enhances Ig class switching and release from B1 cells (1 ? 3, 9, 10, 15, 16). IL-5 also promotes differentiation of basophils and primes them for histamine and leukotriene release (17).

• References:

1. Rosenberg, H. F. et al. (2007) J. Allergy Clin. Immunol. 119:1303.

2. Elsas, P.X. and M. I. G. Elsas (2007) Curr. Med. Chem. 14:1925.

3. Martinez-Moczygemba, M. and D. P. Huston (2003) J. Allergy Clin. Immunol. 112:653.

4. Minamitake, Y. et al. (1990) J. Biochem. 107:292.

5. McKenzie, A. N. et al. (1991) Mol. Immunol. 28:155.

6. Shakoory, B. et al. (2004) J. Interferon Cytokine Res. 24:271.

7. Lalani, T. et al. (1999) Ann. Allergy Asthma Immunol. 82:317.

8. Sakuishi, K. et al. (2007) J. Immunol. 179:3452.

9. Clutterbuck, E. J. et al. (1989) Blood 73:1504.

10. Cameron, L. et al. (2000) J. Immunol. 164:1538.

11. Tavernier, J. et al. (1991) Cell 66:1175.

12. Zaks-Zilberman, M. et al. (2008) J. Biol. Chem. 283:13398.

13. Lipscombe, R. et al. (1998) J. Leukocyte Biol. 63:342.

14. Tavernier, J. et al. (2000) Blood 95:1600.

15. Kopf, M. et al. (1996) Immunity 4:15.

16. Horikawa, K. and K. Takatsu (2006) Immunology 118:497.

17. Denburg, J. A. et al. (1991) Blood 77:1462.

• Long Name:

  Interleukin 5

• Entrez Gene IDs:

  3567 (Human); 16191 (Mouse); 24497 (Rat); 397409 (Porcine); 280825 (Bovine); 403790 (Canine); 493803 (Feline)

• Alternate Names:

  BCDF mu; B-cell differentiation factor I; BCGFII; EDF; Eo-CSF; Eosinophil differentiation factor; IL5; IL-5; IL-5T-cell replacing factor; interleukin 5 (colony-stimulating factor, eosinophil); interleukin-5; TRF; TRFB cell differentiation factor I