Vesicle size and protein concentration quantification of different subpopulations of EVs. (A) The size of EVs in different fractions and at different differentiation time points was measured with a NanoSight particle tracking device. (B) The protein concentration of EVs in different fractions and at different differentiation time points was measured using a microBCA kit. Data plotted are from two independent experiments, each with triplicate qPCR reactions; error bars represent SD from independent samples.