Application Note

Flow Cytometry–Based Exosome Detection And Analysis Using The ZE5 Cell Analyzer

Source: Bio-Rad Laboratories, Inc.

By Yasha Talaga, Elizabeth Dreskin, Joyce Lee

Cell culture

Exosomes are a type of secreted membrane vesicle of approximately 50–100 nm in diameter. They are mainly involved in intracellular communication but also have key roles in several processes such as metastasis and antigen presentation. Since exosomes are secreted in all major bodily fluids, including blood and urine, and carry important cellular information, they have recently emerged as a novel source of potential biomarkers. However, because of their small size in comparison to cells, they can be difficult to characterize and study.

Traditional exosome analysis by flow cytometry requires manual hardware adjustments, advanced instrument calibration, hours of sheath purification, and data manipulation. The ZE5 Cell Analyzer eliminates these hurdles of current exosome research by creating a streamlined process for easier analysis. By using the built-in capabilities of the ZE5, any lab can study exosomes and other small particles. Regardless of the staining method, whether for surface or internal markers, the ZE5 displays optimal sensitivity for small particle identification.

Here, we show that surface exosome marker proteins such as CD63 and CD81, as well as intravesicular markers ALIX and TSG101 can easily be detected using the ZE5 Cell Analyzer. The ZE5 has many unique features that, in addition to studying large cancer cells, allow it to be used in small particle analysis.