Isolation and characterization of exosomes extracted from SVV-infected IBRS-2 cells. A Transmission electron microscopic observation of SVV-exo after negative staining with phosphotungstic acid. B Exosomes were extracted from SVV-infected IBRS-2 cells, and identified by western blot with antibodies directed against Alix, CD9, and CD63. C The Zeta Sizer Nano ZS was used to measure the particle size distribution. The samples were diluted 1: 1000 in PBS containing 0.05% Tween-20 to a total volume of 1.0 mL. The detection was repeated three times with the standard settings (refractive index = 1.331, viscosity = 0.89, and temperature = 25 °C). Each sample was analyzed five times, and the counts were averaged.