Natural killer group 2 member D and other natural killer cell activating receptors (NKG2D and other NKARs)

NKG2D (Natural Killer Group 2 Member D, encoded by KLRK1) and other natural killer (NK) cell activating receptors, including the natural cytotoxicity receptors (NCRs) NKp46, NKp30, and NKp44, are essential components of the innate immune system's ability to detect and eliminate stressed, infected, or malignant cells (UniProt P26718; PMID: 21943794). NKG2D is a C-type lectin-like receptor that recognizes stress-induced ligands such as MICA, MICB, and ULBPs, which are frequently upregulated on the surface of tumor cells (PMID: 30108312). Upon activation, these receptors signal through adapter molecules like DAP10 or CD3ζ to trigger the release of perforin and granzymes, leading to target cell lysis and the production of pro-inflammatory cytokines like IFN-γ (PMID: 28213360). In therapeutic contexts, these receptors are targeted by bispecific and trispecific NK-cell engagers (e.g., SAR443579, AFM13) to redirect NK cell cytotoxicity toward specific tumor antigens (ClinicalTrials.gov NCT04623957). Conversely, blocking the NKG2D pathway is being investigated as a strategy to treat autoimmune conditions like Crohn's disease and rheumatoid arthritis, where overactive NK and T cells contribute to tissue damage (PMID: 25637310).

Other names

KLRK1CD314Natural cytotoxicity receptorsNCRsNKp46NCR1NKp30NCR3NKp44NCR2DNAM-1CD226CD16FCGR3A

Activation of NK cell-mediated cytotoxicity via receptor engagement or blockade of receptor-ligand interactions to inhibit inflammation.