Poster #026, City of Hope
Quantitative image analysis to define circulating extracellular vesicles enriched in different tetraspanin proteins
Mentors: Mihajlo Radmilovic, PhD, PI: Tijana Jovanovic-Talisman, PhD
Extracellular vesicles (EVs) are nanoscale membrane-bound particles involved in intercellular communication and are being investigated as potential biomarkers and therapeutics. However, their small size makes them difficult to visualize and characterize using conventional microscopy techniques. Using Single Extracellular Vesicle Nanoscopy (SEVEN) platform, this study aims to quantify abundance and morphology of EVs enriched in different tetraspanin markers. EVs were captured using antibodies against different tetraspanins and labeled with fluorescent antibodies targeting EV markers, tetraspanins CD9, CD63, and CD81 (TSPAN). Single Molecule Localization Microscopy imaged datasets were analyzed using Nanometrix software to evaluate particle counts, size, shape and TSPAN content. SEVEN provided detailed information about EV subpopulations. While TSPAN EVs were most abundant, several other tetraspanins, including Tspan7 and CD151, were abundant on plasma EVs. By establishing baseline EV characteristics in healthy plasma, these findings support future studies aimed at classifying cell-types specific EV subpopulations, including those present on stem cells.