Biodistribution of unmodified cardiosphere-derived cell extracellular vesicles using single RNA tracing.
Publication Year:
2022
PubMed ID:
35005847
Funding Grants:
Public Summary:
Tiny packages called extracellular vesicles (EVs) carry important signals between cells, but it’s been hard to track how well these packages get into target cells. In this study, scientists developed a new test called DUST that uses a special RNA marker to detect EVs from heart-related cells.
They found that when these EVs are injected into the bloodstream, they mostly go to the heart, especially if the heart is injured. The EVs enter different types of cells, like immune cells and blood vessel cells, better than heart muscle cells. They also showed ways to block EV entry into cells.
This new method helps scientists better understand how these tiny packages travel and get taken up by different cells, which is important for developing EV-based therapies.
Scientific Abstract:
Extracellular vesicles (EVs) are potent signalling mediators. Although interest in EV translation is ever-increasing, development efforts are hampered by the inability to reliably assess the uptake of EVs and their RNA cargo. Here, we establish a novel qPCR-based method for the detection of unmodified EVS using an RNA Tracer (DUST). In this proof-of-concept study we use a human-specific Y RNA-derived small RNA (YsRNA) we dub "NT4" that is enriched in cardiosphere-derived cell small EVs (CDC-sEVs). The assay is robust, sensitive, and reproducible. Intravenously administered CDC-sEVs accumulated primarily in the heart on a per mg basis. Cardiac injury enhanced EV uptake in the heart, liver, and brain. Inhibition of EV docking by heparin suppressed uptake variably, while inhibition of endocytosis attenuated uptake in all organs. In vitro, EVs were uptaken more efficiently by macrophages, endothelial cells, and cardiac fibroblasts compared to cardiomyocytes. These findings demonstrate the utility of DUST to assess uptake of EVs in vivo and in vitro.