NK Cell Receptors


Natural killer (NK) cell effector functions are regulated by integrated signals across the array of stimulatory and inhibitory receptors engaged upon interaction with target cell surface ligands. A delicate balance between activating and inhibiting receptors determines the outcome of NK cell activation. Moreover, NK cell receptors also instruct or confer the responsiveness of NK cells to activation events at both development and mature stages. In pathological condition, some strategies have been developed to tilt the balance of NK cell receptor signalling, which are involved in the onset and progress of malignant tumour, viral infection and other pertinent diseases. More understanding of the nature of interaction of NK cell receptors and their ligands as well as the regulation mechanisms should facilitate the development of effective therapy.

Key Concepts

  • The activity of NK cells is regulated by the delicate balance of signals from inhibitory and stimulatory cell surface receptors engaged upon interaction with their ligands.
  • Inhibitory NK cell receptors for MHC class I molecules not only have a critical role in controlling NK cell responses but also confer the functional competence of NK cells in response to activation signals.
  • Several models (missing‐self and induced‐self recognition model; licensing, arming, rheostat or cis interaction education model) have been proposed to depict the mechanisms for NK cell recognition and adaption.
  • Tumour cells and virus have developed various strategies to tilt the balance of NK cell receptor signalling, leading to escape from NK cell‐mediated immunosurveillance.
  • Therapeutic strategies targeting regulation of NK cell receptor and ligand system have shown great promise for treatment of cancer and viral infectious diseases.

Keywords: NK cell receptor; innate immunity; tumour; viral infection; immune surveillance


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Tian, Zhigang, and Zhang, Cai(May 2015) NK Cell Receptors. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0020179.pub2]