Fig. 3
Binding of low-density lipoprotein (LDL) to breast cancer cell-derived Reg-EVs and Br-EVs. Reg EVs were derived from MDA-MB-231 cells and Br-EVs from MDA-MB-231-BrM2-831 cells. a Enzyme-linked immunosorbent assay (ELISA) measurements of CD63 pre and post-incubation of EVs with LDL. b NTA measurements of EV concentrations pre and post-incubation with LDL. c Schematic of the gravitational flow of EVs and LDL in a size-exclusion chromatography (SEC) column. d ELISA measurements of apolipoprotein B (ApoB) in EVs with and without LDL pre and post-SEC. e NTA measurements of EV concentrations with and without LDL post-SEC. f ELISA measurements of CD63-positive EVs with and without LDL post-SEC. g Atomic force microscopy (AFM) topography and phase images of EVs and LDL. Scale bar, 200 nm. Br-EVs + LDL display large aggregates that are not present in Reg-EVs + LDL. h Merged cross-sectional graph of AFM images. i Schematic illustrating that Br-EVs + LDL present thick and multilayered aggregates that are not present in Reg-EVs + LDL. LDL dose, 500 μg/1010 EVs. Data are presented as mean ± SD of three replicates. Statistical analyses were performed by one-way ANOVA (a, b, d, e, and f) with post-hoc pairwise comparisons calculated with a Tukey’s test. *p ≤ 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. nd not detected