L1CAM and supranuclear palsy, progressive, 1: We found that α-synuclein content in L1CAM-positive exosomes from these diseases is similar to HC as shown in figure 1A (FTD, 12.60±4.03 pg/mL; PSP, 9.20±4.90 pg/mL; CBS, 9.93±3.68 pg/mL).