Figure 4

Transmission electron microscopy (TEM) showing the structure of human and feline EVs. (a) Human plasma derived EVs, (magnification × 87,000, scale bar 200 nm) show a small EV around 200 nm in size. (b) Human plasma derived EVs, (magnification × 16,500, scale bar 1 µm) show small EVs indicated in blue as well as a population of larger vesicles indicated in red. Lipoproteins are also visible in green. (c) Feline plasma derived EVs, (Magnification: × 87,000, scale bar 200 nm) shows an example of a small EV around 150 nm in size (blue). (d) Feline plasma derived EVs, (magnification × 16,500, scale bar 1 µm) show a lower density of small EVs (blue) confirming that there is observationally less EVs in feline plasma than human plasma. No larger EVs were visible, while lipoproteins are also visible in green.