The integrin β1, integrin α6, and integrin β4 subunits in sEVs containing CD81 or CD9 derived from PC3 cells are responsible for the binding of the sEVs to laminin, and the integrin α2 subunit is responsible for the binding of the sEVs to collagen type I. (A–H) The numbers of intact PC3 cell–derived sEVs attached to glass coated with fibronectin, collagen I, and laminin were compared with those of sEVs derived from integrin β1 (A and B), integrin α2 (C and D), integrin α6 (E and F), and integrin β4 (G and H) KO cells. CD81-Halo7 (A, C, E, and G) and CD9-Halo7 (B, D, F, and H) in sEVs were labeled with SF650T. Data are presented as the mean ± SE. n.s., nonsignificant difference; ***P < 0.001 according to Welch’s t test (two-sided).