Dynamic behavior of NK cells during activation in lymph nodes
ABSTRACT During infection, Toll-like receptor agonists induce natural killer (NK)-cell activation by stimulating dendritic cells (DCs) to produce cytokines and transpresent IL-15 to NK cells. Yet the cellular dynamics underlying NK-cell activation by DCs in secondary lymphoid organs are largely unknown. Here, we have visualized NK-cell activation using mice in which NK cells and DCs express different fluorescent proteins. In response to poly I:C or lipopolysaccharide, NK cells maintained a vigorous migratory behavior, establishing multiple short contacts with maturing DCs. Furthermore, mature antigen-loaded DCs that made long-lived interactions with T cells formed short-lived contacts with NK cells. The different behaviors of T cells and NK cells during activation was correlated with distinct calcium responses upon interaction with DCs. That NK cells become activated while remaining motile may constitute an efficient strategy for sampling local concentrations of cytokines around DCs in secondary lymphoid tissues.
- SourceAvailable from: Obinna Chijioke
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- "These activating domains segregate from inhibitory domains that allow MHC class I/KIR interactions and form rapidly within the first minutes of mature DC interaction with NK cells. The rapid establishment of the immunological synapse between mature DCs and resting NK cells, which ensures NK-cell activation and DC protection from NK-cell cytotoxicity at the same time, seems to be important, because in vivo imaging has revealed that DCs and NK cells might only interact with each other in T-cell areas of secondary lymphoid tissues for short periods of time with the majority of contacts being around 1min  . At these early time points, however, the synapse between DCs and NK cells is not stabilized by cytoskeletal components like actin. "
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ABSTRACT: As the PC market is poised to migrate rapidly from bulky CRTs to thin flat panel display (FPD) monitors, a number of interface issues must be resolved to enable and accelerate this transition. This paper addresses a few, but major FPD interface issues, including numerous signal wires, high clock speeds, and lack of a standard interface which prohibits interoperability for plug-and-playWescon/97. Conference Proceedings; 12/1997
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ABSTRACT: A numerical approach based on a Monte Carlo probabilistic method is used as an advantageous alternative to the traditional analytical methods for the evaluation of the uncertainty in measurements achieved by digitally processing sampled input data. The correctness of the approach is shown in the case of both single-channel and multichannel systems. Some practical concerns about the reliability of the proposed methodology are discussed, and suitably designed virtual instruments are presented that are able to present the measurement result along with its uncertainty.IEEE Transactions on Instrumentation and Measurement 07/2004; 53(3-53):672 - 677. DOI:10.1109/TIM.2004.827080 · 1.71 Impact Factor