Comparison of extracellular vesicle isolation and storage methods using high-sensitivity flow cytometry
Fig 6
Effect of storage on stability of EV staining fluorescence determined by HS-FCM.
(A) Samples were labeled with CFDA-SE, purified on a density gradient and EV counts (density of 1.10 g/ml) measured for 30 seconds. Relative number of recorded events (%) in 30 seconds measured after different times up to 28 days of storage at 4°C or -80°C in sucrose. Normalization of events was performed between independent experiments (n = 4) and are presented as the average percentage of recorded events compared to the number of events at day 0 with error bars indicating the standard error of the mean. (B) A representative number distribution of the fluorescence intensity (expressed in units of FITC MESF) after one month of storage at -80°C shows that the intensity distribution is comparable between fresh and stored samples. When samples were stored at 4°C, hardly any fluorescent events were found (not shown).