Fig 2: Confocal microscopy to evaluate the relative expression of CD9, CD63, CD81, CD24, CD44, CD54, CD326 and CD340 membrane protein markers in the exosomes derived from MCF7, MDA-MB-231 and SKBr3 breast cancer cell lines. Magnetic particles appear stained in green while the membrane protein receptors, in red, represents a positive expression on the membrane of the exosomes. In all cases, the primary antibody was 5 μg mL−1 and 2 µg mL−1 of antimouse-Cy5 antibody.

Fig 3: Evaluation of the matrix effect in exosome-depleted human serum using antiCDX-MPs modified with antibodies against CD9, CD24, CD44, CD54, CD63, CD81, CD340 and CD81R (rabbit polyclonal) biomarkers for the IMS, followed by direct labeling with an antiCD63-HRP antibody (1.24 μg mL−1) in depleted human serum. In this instance, no exosomes were spiked in the samples. All other conditions are as in Figure 8. The error bars show the standard deviation for n = 3.

Fig 4: Flow cytometry study for exosomes derived from MCF7, MDA-MB-231 and SKBr3 breast cancer cell lines attached on magnetic particles (MPs), being (Panel A) covalent immobilization of the exosomes on MPs (exosomes-MPs) and (Panel B) IMS of the exosomes on antiCD81-MPs, followed by indirect labeling with mouse antiCDX (5 µg mL−1), (CDX being either CD9, CD24, CD44, CD54, CD63, CD81, CD326 or CD340 biomarkers) and antimouse-Cy5 (2 µg mL−1). The concentrations of MPs and exosomes were set at 1 × 106 MPs and 4 × 109 exosomes per assay, respectively.

Fig 5: Expression of CD44 on monocytes and subsets. (A) Representative histogram of the whole population of human monocytes. (B) Monocyte subsets. Data are presented as the mean ± SEM (n=23). *P<0.05. Data were analyzed using ANOVA with Tukey's post hoc test. ns, non-significant; MFI, mean fluorescence intensity.