• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <1.0 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA.

  When Recombinant Human CD24 Fc Chimera is coated at 5 μg/mL, the concentration of Recombinant Human Siglec-10 Fc Chimera (Catalog # 2130-SL) that produces 50% optimal binding response is found to be approximately 2-10 μg/mL.

• Source

  Mouse myeloma cell line, NS0-derived

  Human CD24 (Met1 - Gly59) Accession # NP_037362	IEGRMD	Human IgG1 (Pro100 - Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Ser27

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  29.7 kDa (monomer)

• SDS-PAGE

  45-55 kDa, reducing conditions

Background: CD24

CD24, also known as Heat-Stable Antigen and Nectadrin, is a heavily and variably glycosylated 30 kDa ? 60 kDa GPI-linked sialoprotein (1 - 4). Human CD24 is expressed on B lineage cells and granulocytes, on epithelial, neuronal, and muscle cells, and on a range of tumor cells (4 - 6). In mouse, CD24 is even more widely expressed, particularly on T cells, monocytes, and dendritic cells (2). CD24 expression is regulated during lineage development and with the activation of various cell types (4). Antibody crosslinking of CD24 enhances the induction of apoptosis in B and T lymphocytes which contributes to negative selection and the induction of immune tolerance (7 - 11). CD24 on antigen presenting cells cooperates with B7 molecules in the costimulation of T cells (12 - 14). CD24 associates   in cis with Siglec-10 (or Siglec-G in mouse) and with the danger-associated molecules HMGB1, HSP70, or HSP90 which are released from necrotic or damaged cells (15). Formation of these ternary complexes fills a protective role: the resulting Siglec-10 signaling inhibits inflammatory responses that are otherwise induced by extracellular DAMPs (15, 16). Mature human CD24 shares 30% and 42% amino acid sequence identity with mouse and rat CD24, respectively.

• References:

1. Jackson, D. et al. (1992) Cancer Res. 52:5264.

2. Kay, R. et al. (1991) J. Immunol. 147:1412.

3. Kadmon, G. et al. (1992) J. Cell Biol. 118:1245.

4. Fang, X. et al. (2010) Cell. Mol. Immunol. 7:100.

5. Fischer, G. F. et al. (1990) J. Immunol. 144:638.

6. Allman, D.M. et al. (1993) J. Immunol. 151:4431.

7. Suzuki, T. et al. (2001) J. Immunol. 166:5567.

8. Taguchi, T. et al. (2003) J. Immunol. 170:252.

9. Jung, K.C. et al. (2004) J. Immunol. 172:795.

10. Kishimoto, H. and J. Sprent (1997) J. Exp. Med. 185:263.

11. Hitsumoto, Y. et al. (1996) Immunology 89:200.

12. Liu, Y. et al. (1992) Eur. J. Immunol. 22:2855.

13. Enk, A.H. and S.I. Katz (1994) J. Immunol. 152:3264.

14. Askew, D. and C.V. Harding (2008) Immunology 123:447.

15. Chen G.Y. et al. (2009) Science 323:1722.

16. Liu, Y. et al. (2011) Curr. Opin. Immunol. 23:41.

• Entrez Gene IDs:

  100133941 (Human); 12484 (Mouse)

• Alternate Names:

  CD 24; CD24 antigen (small cell lung carcinoma cluster 4 antigen); CD24 antigen; CD24 molecule; CD24; CD24A; CD24Asignal transducer CD24; FLJ22950; FLJ43543; MGC75043; Small cell lung carcinoma cluster 4 antigen