• 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 2‑8 ng/mL.

• Source

  E. coli-derived Ala18-Lys144 (Met36Ile, Thr56Ala & Lys126Asn), with an N-terminal Met

• Accession #

• N-terminal Sequence    
  Analysis

  Met

• Predicted Molecular Mass

  14.6 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: GM-CSF

GM-CSF was initially characterized as a factor that can support the in vitro colony formation of granulocyte-macrophage progenitors. It is also a growth factor for erythroid, megakaryocyte, and eosinophil progenitors. GM-CSF is produced by a number of different cell types (including T cells, B cells, macrophages, mast cells, endothelial cells, fibroblasts, and adipocytes) in response to cytokine or inflammatory stimuli. On mature hematopoietic cells, GM-CSF is a survival factor for and activates the effector functions of granulocytes, monocytes/macrophages, and eosinophils (1, 2). GM-CSF promotes a Th1 biased immune response, angiogenesis, allergic inflammation, and the development of autoimmunity (3 - 5). It shows clinical effectiveness in ameliorating chemotherapy-induced neutropenia, and GM-CSF transfected tumor cells are utilized as cancer vaccines (6, 7). The 22 kDa glycosylated GM-CSF, similar to IL-3 and IL-5, is a cytokine with a core of four bundled alpha -helices (8 - 10). Mature feline GM-CSF shares 52% - 56% amino acid sequence identity with mouse and rat GM-CSF and 67% - 72% canine, human, and porcine GM-CSF. GM-CSF exerts its biological effects through a heterodimeric receptor complex composed of GM-CSF R alpha /CD116 and the signal transducing common beta  chain (CD131) which is also a component of the high-affinity receptors for IL-3 and IL-5 (11, 12). In addition, GM-CSF binds a naturally occurring soluble form of GM-CSF R alpha (13). Feline and human GM-CSF show cross-species activity (14, 15).

• References:

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

2. Barreda, D.R. et al. (2004) Dev. Comp. Immunol. 28:509. 

3. Eksioglu, E.A. et al. (2007) Exp. Hematol. 35:1163. 

4. Cao, Y. (2007) J. Clin. Invest. 117:2362. 

5. Fleetwood, A.J. et al. (2005) Crit. Rev. Immunol. 25:405. 

6. Heuser, M. et al. (2007) Semin. Hematol. 44:148. 

7. Hege, K.M. et al. (2006) Int. Rev. Immunol. 25:321. 

8. Kaushansky, K. et al. (1992) Biochemistry 31:1881.

9. Diederichs, K. et al. (1991) Science 254:1779.

10. Dunham, S.P. and J. Bruce (2004) Gene 332:97.

11. Onetto-Pothier, N. et al. (1990) Blood 75:59.

12. Hayashida, K. et al. (1990) Proc. Natl. Acad. Sci. 87:9655.

13. Pelley, J.L. et al. (2007) Exp. Hematol. 35:1483.

14. Sprague, W.S. et al. (2005) J. Comp. Pathol. 133:136.

15. Dunham, S.P. and J. Bruce (2004) Gene 332:97.

• Long Name:

  Granulocyte Macrophage Growth Factor

• Entrez Gene IDs:

  1437 (Human); 12981 (Mouse); 116630 (Rat); 397208 (Porcine); 403923 (Canine); 493805 (Feline)

• Alternate Names:

  colony stimulating factor 2 (granulocyte-macrophage); Colony-stimulating factor; CSF; CSF2; GMCSF; GM-CSF; GMCSFgranulocyte-macrophage colony-stimulating factor; granulocyte-macrophage colony stimulating factor; MGC131935; MGC138897; molgramostin; sargramostim