Recombinant Human CD83 Fc Chimera Protein, CF 50 UG

• Purity

  >90%, 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 the ability of the immobilized protein to support the adhesion of human monocyte-derived dendritic cells. When 5 x 10    ⁴ cells/well are added to human CD83/Fc Chimera coated plates (5 µg/mL, 100 µL/well), approximately 50-75% will adhere after 30 minutes at 37° C.    
     Optimal dilutions should be determined by each laboratory for each application.  

• Source

  Spodoptera frugiperda,     Sf 21 (baculovirus)-derived

  Human CD83 (Thr20 - Ala143) Accession #Q01151	DIEGRMD	Human IgG1 (Pro100 - Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Thr20

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  40.7 kDa (monomer)

• SDS-PAGE

  51-54 kDa, reducing conditions

Background: CD83

Human CD83 is a 40 - 50 kDa member of the Siglec (or sialic-acid-binding immunoglobulin-like lectin) family of transmembrane proteins (1, 2, 3). CD83 is synthesized as a type I transmembrane glycoprotein that contains a 125 amino acid (aa) extracellular region, a 22 aa transmembrane segment, and 39 aa cytoplasmic domain. It contains one V type Ig-like domain in the extracellular region with no inhibitory cytoplasmic motif(s). Although in vitro studies suggest CD83 may form membrane-bound covalent homodimers, in vivo this does not appear to be the case (1, 4). In the extracellular region, mouse and human CD83 are 66% aa identical (1, 2, 4, 5). Relative to human, mouse CD83 is 11 aa shorter in its extracellular domain and is expressed as a 30 - 35 kDa protein (1, 4, 5). Human CD83 is active in the mouse system (4). One alternate splice form has been reported. This leads to a small monomeric soluble form of 74 aa that includes aa’s # 20 - 52 and # 164 - 205 (6, 7). In human, proteolytic cleavage and solubilization of CD83 has also been suggested, and this could lead to dimeric circulating CD83 (4, 6). CD83 is a primary marker for dendritic cells (3, 6, 8). It is also found on B cells (6, 9), neutrophils (10), monocytes and macrophages (11). Except for dendritic cells, CD83 expression is often transient. CD83 binds to sialic acids on target cells (12). The function of CD83 is only now becoming clear. Membrane CD83 appears to promote T cell proliferation, particularly of CD8⁺ cytotoxic T cells (13, 14). Soluble CD83, however, appears to be immunosuppressive and blocks T cell activation (15, 16). On monocytes, CD83 is suggested to drive monocytes into a fibrocyte phenotype (13). A lack of membrane-expressed CD83 leads to an unusual IL-4/IL-10 producing CD4⁺ T cell phenotype (17).

• References:

1. Zhou, L-J. et al. (1992) J. Immunol. 149:735.

2. Kozlow, E.J. et al. (1993) Blood 81:454.

3. Fujimoto, Y and T.F. Tedder (2006) J. Med. Dent. Sci. 53:85.

4. Lechmann, M. et al. (2005) Biochem. Biophys. Res. Commun. 329:132.

5. Berchtold, S. et. al. (1999) FEBS Lett. 461:211.

6. Hock, B.D. et al. (2001) Int. Immunol. 13:959.

7. Dudziak, D. et al. (2005) J. Immunol. 174:6672.

8. Velten, F.W. et al. (2007) Mol. Immunol. 44:1544.

9. Cramer, S.O. et al. (2000) Int. Immunol. 12:1347.

10. Yamashiro, S. et al. (2000) Blood 96:3958.

11. Cao, W. et al. (2005) Biochem. J. 385:85.

12. Scholler, N. et al. (2001) J. Immunol. 166:3865.

13. Scholler, N. et al. (2002) J. Immunol. 168:2599.

14. Hirano, N. et al. (2006) Blood 107:1528.

15. Kotzor, N. et al. (2004) Immunobiology 209:129.

16. Zinser, E. et al. (2006) Immunobiology 211:449.

17. Garcia-Martinez, L.F. et al. (2004) J. Immunol. 173:2995.

• Entrez Gene IDs:

  9308 (Human); 12522 (Mouse)

• Alternate Names:

  B-cell activation protein; BL11; BL11CD83 antigen; CD83 antigen (activated B lymphocytes, immunoglobulin superfamily); CD83 molecule; CD83; Cell surface protein HB15; cell-surface glycoprotein; HB15; HB15hCD83