Fig. 3.

In vivo biodistribution of EVs. (A-B) Representative IVIS images of organs harvested from mice at 2 and 6 h after intravenous injection of Cy7-labeled M2-EVs or MSC-EVs. Mice that received PBS and Cy7 dye alone were included as negative controls. (C—D) Quantification of the fluorescence intensity of M2-EVs or MSC-EVs in different organs of mice (n = 3). (E) Representative micrographs of Cy7-EVs (red) in tissue sections. Spleen tissues were costained with CD68⁺ macrophages (green) and DAPI (blue). The white arrow indicates the colocalization of green and red signals (scale bar = 50 μm for lung and liver, scale bar = 20 μm for spleen). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)