CD81 and hypertensive disorder: EVs extracted from hypertensive patients were characterized according to the criterion outlined for Minimal Information for Studies of Extracellular Vesicles, 2018 guidelines.22 The presence of the exosomal marker protein CD63 on the surface of EVs was validated by immunogold labeling transmission electron microscopy (Figure 1A).18, –20 Plasma and urine EVs from group 1 (controlled hypertensives) and group 2 (noncontrolled hypertensives) patients were further characterized by flow cytometry for surface markers (CD63, CD9, and CD81) (Figure 1B).