Exosomes, the natural vehicles of intercellular communication, transfer proteins, mRNAs and microRNAs (miRNAs) and mediate many physiological and pathological processes. It is not clear that whether exosomal miRNAs could regulate gene expression across species, though some studies suggest interactions of exosomal miRNAs between cells. In this report, researchers from Southeast University have isolated exosomes from rat PC12 cells and assessed their internalization by human cancer Hela cells. The internalized exosomes were located in Hela lysosomes. Human PTEN expression was significantly deregulated due to miR-21 delivered by rat cell exosomes. These results demonstrate that exosomes could incorporate between cells of different species and could regulate the protein expressions in the recipient cells by delivering the enclosed miRNAs. Thus this study foreshadows a futuristic treatment approach of utilizing miRNA enclosed exosome vehicles sans species concerns in combating various diseases/ regulating abnormal proteins.
Time-lapse images of Hela cells after incubation with CFSE-labeled exosomes (green)
Merge of bright field with wide-field fluorescence images at 5 min (A), 3 h (B), 6 h (C), 12 h (D), and 24 h (E) after exosomes adding, respectively. Scale bar, 25 μm.