"Natural Killer Cells As Natural Born Killers": Directed by the Activated GTPase Dynamin-2
Farrar, Benjamin D.
Almost an enigma in the immunological world are Natural Killer (NK) cells - a distinct class of cytotoxic lymphocytes. Their ability to kill tumor and virally-infected cells without prior sensitization makes them unique when compared to other cytotoxic lymphocytes. Once activated via the cross-linking of the Fc receptor (FcR) of either the antibody dependent cellular cytotoxicity (ADCC) or natural cytotoxicity (NC) pathway, a cascade of signals activates various intracellular proteins that eventually lead to NK. cell activation. Ultimately, the activated NK cells kill various target cells by releasing protease-filled granules from a polarized area of sphingolipids and receptors at the interface between the NK. cell and its target. Recently, a new protein GTPase called dynamin-2 has been hypothesized to be specifically involved in the NK cell activation, cell-mediated killing and lipid and granule polarization processes. The postulation was made about dynamin-2 because it has been found to be present at the necks of newly forming vesicles at the trans-Golgi network. The results from this study suggest that once activated in the NK cell activation process, dynamin-2 has been found to influence further NK cell activation, cell-mediated killing, and both lipid and granule polarization. Specifically, over-expression of dynamin-2 was shown to positively enhance all of these processes, further supporting its role in NK cell functions. These results further underscore the pivotal role of the GTPase dynamin-2 in mediating NK cell functions.
vi, 38 p.
U.S. copyright laws protect this material. Commercial use or distribution of this material is not permitted without prior written permission of the copyright holder.