As shown in Figure 5A, using antibody 19-64-17, the median ratio of principal cell-specific AQP2 abundance in urinary extracellular vesicles was significantly higher in deceased-donor recipients with acute kidney injury compared to immediate allograft function (median 2.05; IQR 0.87 to 2.83; vs. median 0.81; IQR 0.44 to 1.78; p < 0.01 by Mann–Whitney test). Here, AQP2 is linked to acute kidney injury.