New Apoptosis Monitoring Tool for Microscopy & Flow Cytometry
pSIVA is a novel phosphatidylserine (PS) exposure reporter for monitoring cell death, apoptosis and survival by live-cell imaging. Live-cell imaging is a vital application for studying dynamic biological processes such as apoptosis in real time. However, prior to the advent of pSIVA, there had been a lack of available reporters for studying cell death/survival processes.
pSIVA is conjugated to IANBD, a polarity sensitive dye that fluoresces only when pSIVA is bound to the cell membrane.
First developed by Dr. Ralf Langen and his colleagues at USC in 2010, pSIVA already has several impressive publications (1-3). pSIVA’s most notable live-imaging applications including monitoring the subcellular onset of PS externalization, tracking PS exposure throughout the death process (Movies 1 and 2), and demonstrating reversible PS exposure events associated with rescuable cell death (Movie 3). The demonstration of reversible PS exposure by pSIVA is considered to be among the most significant assay advances in the Cell Death and Apoptosis field today. In addition to live cell imaging, pSIVA can also be used for standard fluorescence microscopy, in vivo analysis of cell death and flow cytometry.
pSIVA (Apoptosis Pathway Kinetics) Product Citations :
1. Engineering a polarity–sensitive biosensor for time-lapse imaging of apoptotic processes and degeneration. Kim YE, J Chen, JR Chan, R Langen. Nat Methods 7:67-73 (2010).
2. Monitoring apoptosis and neuronal degeneration by real-time detection of phosphatidylserine externalization using a polarity-sensitive indicator of viability of apoptosis. Kim YE, J Chen, R Langen, JR Chan. Nature Protocols 5:1396-1405 (2010).
3. Zhang CQ, Yeh T-l, A Leyva, LG Frank, J Miller, YE Kim, R Langen, S Finkbeiner, ML Amzel, CA Ross, MA Poirier. A compact B model of huntingtin toxicity. JBC 286:8188-8196 (2011).