Natural Killer Group 2D Receptor Ligand (NKG2DL)

Natural killer group 2D receptor ligands (NKG2DLs) are a family of cell surface proteins recognized by the NKG2D receptor, an activating immunoreceptor found on natural killer (NK) cells and certain T cell subsets. These ligands are typically upregulated in response to cellular stress, such as infection, DNA damage, or malignant transformation. In humans, the main NKG2D ligands include MICA, MICB, and ULBP1–ULBP6. Binding of these ligands to the NKG2D receptor activates NK cells and some T cell subsets, triggering cytotoxicity against target cells and cytokine secretion. They are a target for cancer immunotherapy.

Other names

MHC class I chain-related protein AMICAMHC class I chain-related protein BMICBUL16-binding protein 1ULBP1UL16-binding protein 2ULBP2UL16-binding protein 3ULBP3UL16-binding protein 4ULBP4UL16-binding protein 5ULBP5UL16-binding protein 6ULBP6

NKG2DLs bind to the NKG2D receptor on NK cells and some T cell subsets, triggering activation through DAP10 (humans) and DAP10/DAP12 (mice) signaling pathways. This leads to cytotoxicity and cytokine production.