• Purity

  >95%, 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 GM-CSF-dependent proliferation of TF‑1 human erythroleukemic cells. The ED    ₅₀ for this effect is 1.25-5 μg/mL in the presence of 40 pg/mL of rhGM-CSF.

• Source

  Mouse myeloma cell line, NS0-derived Leu20-Gly320, with a C-terminal 10-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Leu20

• Predicted Molecular Mass

  36.2 kDa

• SDS-PAGE

  60-70 kDa, reducing conditions

Background: GM-CSF R alpha

Granulocyte macrophage colony stimulating factor receptor alpha (GM-CSF R alpha ), also known as CD116, is a component of the receptor complex that mediates cellular responses to GM-CSF. GM-CSF promotes the differentiation and mobilization of granulocyte-macrophage, erythroid, megakaryocyte, and eosinophil progenitors. It enhances the activation of myeloid cell effector functions and plays a role in the development of Th1 biased immune responses, allergic inflammation, and autoimmunity (1 - 4). Mature human GM-CSF R alpha is an 80 kDa type I transmembrane glycoprotein that consists of a 298 amino acid (aa) extracellular domain (ECD) with two fibronectin type III domains and a juxtamembrane WSXWS motif, a 26 aa transmembrane segment, and a 54 aa cytoplasmic domain (5). Within the ECD, human GM-CSF R alpha shares approximately 33% aa sequence identity with mouse and rat GM-CSF R alpha. Alternate splicing of human GM-CSF R alpha generates several additional isoforms that lack the cytoplasmic and/or transmembrane regions. Soluble forms of the receptor retain the ability to bind GM-CSF (6, 7). GM-CSF R alpha is expressed on hematopoietic stem cells, progenitor and differentiated cells in the myeloid lineage, vascular endothelial cells, placenta, and non-hematopoietic solid tumor cells (8). GM-CSF R alpha associates with the common beta chain/CD131 ( beta _c), a 135 kDa transmembrane protein that is also the signal transducing component of the receptors for IL-3 and IL-5 (9, 10). Association with beta _c converts GM-CSF R alpha from a low affinity to a high affinity receptor for GM-CSF (9 - 11). The shared usage of beta _c underlies the synergism between GM-CSF, IL-3, and IL-5 in their effects on myeloid cell differentiation and activation (1, 2).

• References:

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

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

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

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

5. Gearing, D.P. et al. (1989) EMBO J. 8:3667.

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

7. Raines, M.A. et al. (1991) Proc. Natl. Acad. Sci. 88:8203.

8. Chiba, S. et al. (1990) Cell Regul. 1:327.

9. Kitamura, T. et al. (1991) Proc. Natl. Acad. Sci. 88:5082.

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

11. Hoang, T. et al. (1993) J. Biol. Chem. 268:11881.

• Long Name:

  Granulocyte Macrophage Growth Factor Receptor alpha

• Entrez Gene IDs:

  1438 (Human); 12982 (Mouse)

• Alternate Names:

  CD116 antigen; CD116; CDw116; colony stimulating factor 2 receptor alpha subunit; colony stimulating factor 2 receptor, alpha, low-affinity(granulocyte-macrophage); CSF2R; CSF2RA; CSF2RAX; CSF2RAY; CSF2RX; CSF2RY; GM-CSF R alpha; GM-CSF receptor alpha subunit; GMCSFR alpha; GMCSFR; GM-CSFRa; GM-CSF-R-alpha; GMCSFR-alpha; GMR; GMR-alpha; granulocyte-macrophage colony-stimulating factor receptor alpha chain; granulocyte-macrophage colony-stimulating factor receptor subunit alpha; MGC3848; MGC4838