Figure 1.

ECs isolated from EC^iZSGreen mice secrete ZSGreen⁺ EVs that are derived from endosomes. (a) Schematic of the experimental approach. (b) Isolated ZSGreen⁺ lung ECs maintain brilliant ZSGreen fluorescence in vitro (left panel). At right, purified EVs from ZSGreen⁻ ECs and ZSGreen⁺ ECs under a fluorescent lamp (488 nm) are shown. ZSGreen⁻ EC-EVs are shown at left, and at right are ZSGreen⁺ EC-EVs (white arrowhead). (c) Immunohistochemistry of the endosomal marker Lamp1 (red fluorescence) and ZSGreen demonstrating their co-localization. (d) FACS plots and gating of ZSGreen⁺ EVs from the culture medium of ZSGreen⁺ ECs.