Natural Killer Cell

The predominant targets of NK cells are ‘stressed’ cells with downregulated expression of class I MHC (MHC-I), a common mechanism used by malignant or virus-infected cells to evade recognition by the body’s immune system. In response to encountering these cells, NK cells release two types of proteins, perforins and granzyme B, which attack the target cell’s membrane, damage its organelles, and trigger apoptosis. NK Cell immunotherapy is an emerging anti-cancer strategy, as these cells are able to exert effects without activating the graft-versus-host disease cascade. In addition, their broad mechanism allows for generally safe administration of NK cells that are not immunologically matched to a patient.