Table 1.
Inhibitory and activating receptors for HLA class I molecules
| Receptor | Ligand |
|---|---|
| Inhibitory | |
| KIR2DL2/3 | HLA-C group1 (Cw1, Cw3) |
| KIR2DL1 | HLA-C group 2 (Cw2, Cw4) |
| KIR3DL1 | HLA-A and B with Bw4 motifs at position 77–83 |
| CD94/NKG2A/E | HLA-E |
| KIR3DL2 | HLA-A3/A11 |
| KIR2DL4 | HLA-G |
| Activating | |
| KIR2DS4 | |
| KIR2DS1 | HLA-C2 |
| KIR2DS2 | |
| KIR2DS3 | |
| KIR2DS5 | |
| KIR3DS1 | |
| KIR Haplotype | |
| A | Inhibitory KIR and KIR2DS4 |
| B | Inhibitory KIR and combinations of activating KIR |
KIR genes are organized into diverse haplotypes, which have simplified into Groups A and B.