• 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 by flow cytometry for its ability to bind a ligand expressed in FasL-treated mouse B cells. Sancho, D.     et al. (2009) Nature     458:899. At 100 ng/mL, >50% of necrotic cells bind to Recombinant Human CLEC9a.

• Source

  Mouse myeloma cell line, NS0-derived

  Met-Asp	Human IgG1 (Pro100-Lys330)	IEGR	Human CLEC9a (Lys57-Val241) Accession # Q6UXN8
  N-terminus			C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Met

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  47.8 kDa (monomer)

• SDS-PAGE

  55-65 kDa, reducing conditions

Background: CLEC9a

CLEC9A (C-type lectin domain family 9 member A), also known as DNGR-1, is a type II transmembrane glycoprotein member of the C-type lectin superfamily (1). Mature mouse CLEC9A consists of a 35 amino acid (aa) cytoplasmic domain with an ITAM-like motif, a 21 aa transmembrane segment, and a 185 extracellular domain (ECD) that contains a stalk region and one C-type lectin domain (CTLD) (2-4). Within the ECD, human CLEC9A shares 57% aa sequence identity with mouse and rat CLEC9A. Although the CTLD of CLEC9A structurally resembles that of other C-type lectins, it lacks the conserved residues that typically mediate calcium and carbohydrate binding. CLEC9A is expressed as a disulfide-linked homodimer of approximately 50 kDa N-glycosylated subunits (2, 4). Human CLEC9A expression is restricted to a subpopulation of BDCA-3  ⁺ conventional dendritic cells (cDC) and CD16  ^- monocytes (2-5). BDCA-3  ⁺ cDC are analagous to mouse CD8  ⁺ cDC which are specialized in antigenic cross-presentation in complex with MHC class I molecules (6). In mouse, CLEC9A is additionally expressed on plasmacytoid dendritic cells (3, 4). CLEC9A ligation enhances antigen uptake and processing, leading to presentation on MHC class I and cytotoxic T cell (CTL) priming (2-5, 7). Its recognition of filamentous actin in dead cells is important for triggering an immune response to necrotic cell debris (8-10). CLEC9A is also required for the presentation of viral proteins and the subsequent CTL-mediated killing of virus-infected cells (11, 12). CLEC9A signaling triggers activation of the tyrosine kinase Syk (2, 8).

• References:

1. Kerrigan, A.M. and G.D. Brown (2010) Immunol. Rev. 234:335.

2. Huysamen, C. et al. (2008) J. Biol. Chem. 283:16693.

3. Caminschi, I. et al. (2008) Blood 112:3264.

4. Sancho, D. et al. (2008) J. Clin. Invest. 118:2098.

5. Schreibelt, G. et al. (2012) Blood 119:2284.

6. Dudziak, D. et al. (2007) Science 315:107.

7. Poulin, L.F. et al. (2010) J. Exp. Med. 207:1261.

8. Sancho, D. et al. (2009) Nature 458:899.

9. Ahrens, S. et al. (2012) Immunity 36:635.

10. Zhang, J.-G. et al. (2012) Immunity 36:646.

11. Iborra, S. et al. (2012) J. Clin. Invest. 122:1628.

12. Zelenay, S. et al. (2012) J. Clin. Invest. 122:1615.

• Long Name:

  C-type Lectin-like Receptor 9

• Entrez Gene IDs:

  283420 (Human); 232414 (Mouse)

• Alternate Names:

  CD370; CLEC9a; C-type lectin domain family 9 member A; C-type lectin domain family 9, member A; DNGR1; HEEE9341; UNQ9341