Using combinations of unconjugated and conjugated antibodies, we characterized subpopulations of exosomes from plasma and total blood and found that subpopulation compositions of exosomes from plasma and total blood of HFs and BCPs were similar: CD24/CD9 > CD9/CD81 > CD24/CD63 ≈ CD9/CD63 (Table 3). Here, CD81 is linked to Hand-foot syndrome.