Urine exosome mRNA-based test for monitoring kidney allograft rejection: Effects of sample transportation and storage, and interference substances

Figure 5 Effect of blood on performance of the exosome molecular assay. Urine samples derived from 4 donors were utilized, and blood or serum was spiked into urine before exosome purification. Levels of 9 mRNA targets were analyzed by quantitative polymerase chain reaction; the graph displays Ct values (y-axis). Conditions left to right: control urine specimens, processed following the standard protocol; urine specimens spiked with 1% blood and processed without additional centrifugation; urine specimens spiked with 1% blood and pre-processed following the standard protocol (centrifugation for 20 min at 2000 × g); urine specimens spiked with 1% serum and processed without additional centrifugation.