flow-cytometric-analysis-extracellular-vesicles-from-cell-conditioned

Flow Cytometric Analysis of Extracellular Vesicles from Cell-conditioned Media

Flow cytometry (FC) is the method of choice for semi-quantitative measurement of cell-surface antigen markers. Recently, this technique has been used for ...

Cardiocentro Ticino Foundation, Switzerland

Cell therapy trials using cardiac-resident progenitor cells (CPCs) and bone marrow-derived mesenchymal stem/progenitor cells (BMCs) in patients after myocardial infarction have provided encouraging results. Exosomes, nanosized extracellular vesicles of endosomal origin, figure prominently in the bioactivities of these cells. However, a head-to-head comparison of exosomes from the two cell types has not been performed yet.

Cardioprotection by cardiac progenitor cell-secreted exosomes: role of pregnancy-associated plasma protein-A.

Cell therapy has been evaluated to enhance heart function after injury. Delivered cells mostly act via paracrine mechanisms, including secreted growth factors, cytokines, and vesicles, such as exosomes (Exo). Intramyocardial injection of cardiac-resident progenitor cells (CPC)-derived Exo reduced scarring and improved cardiac function after myocardial infarction in rats. Here, we explore a clinically relevant approach to enhance the homing process to cardiomyocytes (CM), which is crucial for therapeutic efficacy upon systemic delivery of Exo. By overexpressing exosomal CXCR4, we increased the efficacy of plasmatic injection of cardioprotective Exo-CPC by increasing their bioavailability to ischemic hearts. Intravenous injection of Exo significantly reduced infarct size and improved left ventricle ejection fraction at 4 weeks compared to Exo ( < 0.01). Hemodynamic measurements showed that Exo improved dp/dt min, as compared to Exo and PBS group. In vitro, Exo was more bioactive than Exo in preventing CM death. This in vitro effect was independent from SDF-1α, as shown by using AMD3100 as specific CXCR4 antagonist. We showed, for the first time, that systemic administration of Exo derived from CXCR4-overexpressing CPC improves heart function in a rat model of ischemia reperfusion injury These data represent a substantial step toward clinical application of Exo-based therapeutics in cardiovascular disease.

Sara Bolis

Cellular and Molecular Cardiology Laboratory

Cardiocentro Ticino Foundation, Switzerland

Flow Cytometric Analysis of Extracellular Vesicles from Cell-conditioned Media

Sara Bolis

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Cellular and Molecular Cardiology Laboratory

Cardiocentro Ticino Foundation, Switzerland

Flow Cytometric Analysis of Extracellular Vesicles from Cell-conditioned Media

Cellular and Molecular Cardiology Laboratory