Fig 1: Comparison between PCa patients (n=6) and health control (n=6) using different EV metrics with three different kits. (A–C) PSA positive EVs, (D–F) PSA positive EVs/total EVs, and (G–I) Total EVs. No significant difference was observed between PCa patients and healthy controls (HC) based on PSA-specific EVs or total EVs for all the three methods. Only qEV70 shows some difference between PCa patients and HC when using PSA positive EVs/total EVs as the metrics. As different fluorescence stains in the detection marker were used for PSA and EVs (Alexa Fluor 405 for PSA and APC for EVs), the fluorescence signals from PSA is more intensive than EVs, which leads to the RFI ratio of PSA+ EV/total EV >1. *P < 0.05. Two-tail t-test was used for (A–I).