Natural killer (NK) cells are large granular lymphocytes capable of clearing both virus-infected and transformed cells. NK cell cytotoxicity is controlled by the integration of activating and inhibitory receptor signaling at the NK cell immune synapse (IS) formed between NK and target cells. NK cells can also respond by producing cytokines, e.g., interferon-γ (IFN-γ) or tumor necrosis factor-α (TNF-α), and are known to be activated by cytokines like interleukin (IL)-2, IL-12, and IL-15. Activating receptors, such as DNAM-1, NKp44, and KLRB1, are upregulated, while inhibitory receptors, like KIR2DL2 and KIR3DL3, are downregulated after exposure to IL-2. In addition, increased cell-cell adhesion has been directly coupled to cytotoxicity. NK cells are able to lyse target cells but require the right combination of activating signals, and, therefore, seem more tightly regulated than IL-2-activated NK cells.

In our lab, we are focusing on the identification of cytotoxic dynamics of NK cells. Using time-lapse imaging, we examine "cytotoxic dynamics", such as killing behavior, contact dynamics, motility and directionality of NK cells as well as dying process of cancer cells.