• Purity

  >90%, 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 its ability to bind HEK293T human embryonic kidney cells in a flow cytometry assay. When 10 μg of Recombinant Human KIR2DL3/CD158b2 Fc Chimera is added to 5 x 10    ⁵ HEK293T cells, >20% of the cells will bind to the protein.

• Source

  Mouse myeloma cell line, NS0-derived

  Human KIR2DL3 (His22-His245) Accession # P43628	IEGRMD	Human IgG1 (Pro100-Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  His22

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  51.2 kDa (monomer)

• SDS-PAGE

  66-75 kDa, reducing conditions

Background: KIR2DL3/CD158b2

KIR2DL3 (2DL3, formerly NKAT2, designated CD158b2) is a 341 amino acid (aa) type I transmembrane glycoprotein that belongs to the human killer cell Ig‑like receptor (KIR) family of molecules (1, 2). KIRs are expressed on human CD56  ^dim NK cells and T cell subsets, and regulate effector functions in the innate immune system (1-3). KIRs are named for the number of Ig‑like domains (2D or 3D) in the extracellular domain (ECD), and whether they have long or short (L, S) cytoplasmic tails (1‑3). Individuals will express varying subsets of inhibiting and activating KIRs with varying polymorphisms (1, 4). Like other inhibiting KIRs, KIR2DL3 has two ITIM domains within its long tail that block activating receptor clustering (2). Within the ECD, KIR2DL3 shares very high aa sequence identity (98%) with KIR2DL2. The two segregate as alleles of the same gene; both recognize Asn80‑containing HLA‑C1 and, more weakly, Lys80‑containing C2 allotypes (1, 5). Extracellular aa identity is also high for KIR2DL1 (93%). The three molecules together recognize and inhibit NK cytotoxicity against cells expressing any HLA‑C allotype, allowing for self‑recognition (1‑3). Compared with KIR2DL2, KIR2DL3 shows lower avidity for HLA‑C1 ligands; when compared to KIR2DL1, KIR2DL3 has lower avidity but broader specificity for HLA-C1 ligands (1, 5, 6). Configurations of inhibiting and activating KIR can alter an individual’s susceptibility to viral and autoimmune diseases and leukemia (1‑3). For example, rheumatoid arthritis patients that are positive for KIR2DL3 and negative for KIR2DS3 have an earlier disease diagnosis (7).

• References:

1. Purdy, A.K. and Campbell, K.S. (2009) Cancer Biol. Ther. 8:13.

2. Lanier, L. L. (2005) Annu. Rev. Immunol. 23:225.

3. Kulkarni, S. et al. (2008) Semin. Immunol. 20:343.

4. Middleton, D. and F. Gonzelez (2009) Immunology 129:8.

5. Moesta, A.K. et al. (2008) J. Immunol. 180:3969.

6. Hilton, H.G. et al. (2012) J. Immunol. 189:1418.

7. Majorczyk, E. et al. (2007) Genes Immun. 8:678.

• Long Name:

  Killer Cell Immunoglobulin-like Receptor, Two Domain Long Cytoplasmic Tail, 3

• Entrez Gene IDs:

  3804 (Human)

• Alternate Names:

  CD158 antigen-like family member B2; CD158b2 antigen; CD158b2; CD158B2CD158b; cl-6; killer cell immunoglobulin-like receptor 2DL3; killer cell immunoglobulin-like receptor, two domains, long cytoplasmic tail, 3; Killer inhibitory receptor cl 2-3; KIR-023GB; KIR2DL3; KIRCL23; KIR-K7b; KIR-K7c; MGC129943; MHC class I NK cell receptor; natural killer associated transcript 2; natural killer cell inhibitory receptor KIR2DL3; Natural killer-associated transcript 2; NKAT; NKAT2; NKAT-2; NKAT2A; nkat2b; NKAT2GL183; NK-receptor; p58 natural killer cell receptor clone CL-6; p58 NK receptor CL-6; p58; p58.2 MHC class-I specific NK receptor; p58.2 MHC class-I-specific NK receptor