Figure 3
Titer determination by flow cytometer. (A) Titers of two virus samples (A and B) analyzed three times by the 18 h fluorescent based flow cytometric assay and end-point dilution method. (B) Consistency of the titers determined by flow cytometer after 18 hours of incubation. (C) Titer determined with flow cytometer 24 hours post infection led to overestimation of virus titer. In average titer determined 24 hours post infection were 4 times higher than the ones determined 18 hours post infection. This might be due to viral spread and secondary infections. (D) Comparison of the end-point titer and the titer determined by flow cytometer. Correlation coefficient (R = 0.9924) indicated good correlation between the two titration methods.