Fig. 1

Pulmonary metastatic TNBC-derived exosomes modify the pulmonary vascular niche. (A) Schematic representation of organ tissue post-exosome injection in mice. (B) Flow cytometry analysis depicting lung resident cell uptake of 231 LuT3 exosomes. (n = 5). (C) IF co-staining of 231 LuT3 exosomes (green) with either S100A4 (fibroblasts) or CD31 (endothelial cells) in mouse lung samples. Scale bars: 50 μm. (D) LuEC treatment with PKH67-tagged exosomes (green) for 24 h, counterstained using Phalloidin (red) and DAPI (blue). Scale bars: 20 μm. (E-G) LuEC monolayers were treated with either PBS or exosomes for 24 h. (E) IF detection of ZO-1 (red). Scale bars: 20 μm. (F) Permeability assessment of treated LuEC monolayers on transwell filters using 20 mg/mL rhodamine-dextran (n = 3). (G) Evaluation of the tube formation (n = 5). Scale bars: 200 μm. (H) IF double-labeling of CD31 (red) and ZO-1 (green) in mouse lung tissues post 24-hour exosome treatment. Scale bars: 100 μm. (I) In vivo visualization of pulmonary vascular permeability via rhodamine-dextran (red) presence (n = 5). Scale bars: 100 μm. Data shown as mean ± SD