The Antitumor Immunity Mediated by NK Cells: The Role of The NCRs

Mona Rady*, Khaled Abou-Aisha
Microbiology and Immunology Department, German University in Cairo (GUC), New Cairo, Egypt

© 2018 Rady and Abou-Aisha.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Microbiology and Immunology Department, German University in Cairo (GUC), New Cairo, Egypt, Tel: +201005633776; E-mails:;


Natural Killer (NK) cells are innate immune lymphocytes that are important for early and effective immune responses against infections and cancer. The antitumor immunity mediated by NK cells can be exerted through several direct or indirect “immunosurveillance” mechanisms that control tumor growth and prevent the rapid dissemination of metastatic tumors. NK cells express an array of activating and inhibitory receptors that enable them to recognize and bind non-self as well as self-ligands expressed on the surface of malignant or virally infected cells. The family of Natural Cytotoxicity Receptors (NCRs) comprises three activating receptors; NKp30, NKp44, and NKp46 that are important for the stimulation of NK cell effector functions. This review summarizes the mechanisms of antitumor immunity mediated by natural killer cells with focus on the role of the family of the NCRs and their tumor associated ligands.

Keywords: Natural Killer (NK) cells, Innate immune lymphocytes, Immunosurveillance mechanisms, Natural cytotoxicity receptors, Tumor growth, Metastatic tumors.