Vero cells in suspension were incubated with serial dilutions of a known concentration of West Nile virus (WNV) for 30 minutes at 37°C, followed by immediate addition of the cell/virus suspension to wells of ACEA’s electronic microtiter plates (E-Plates). In contrast to uninfected control cells which grew to confluency and maintained a plateaued Cell Index (CI), virus-infected cells displayed a time-dependent decrease of CI down to zero, indicating complete cell lysis. Importantly, the time at which this cytopathic effect occurred correlated extremely well with the known titer of the virus. This is highlighted by plotting the CIT50 (time required for the CI to decrease by 50%) as a function of virus titer. Using this type of standard curve, it is possible to determine the viral titer in samples of unknown concentration.
Read more