Extracellular Vesicles: The Wonder-somes - What's the hold up?

Why is it that scientific discoveries often take years — or even decades — to be fully recognised for their value? Perhaps it’s because technological advancements are needed to reveal their true significance, or because the body of knowledge must first grow to embrace new theories that spark further research. More likely, it’s the convergence of both: the evolution of technology meeting the maturity of ideas.

In 1946 Erwin Chargaff reported “The particulate fraction sedimented at 31,000 g probably includes, in addition to the thromboplastic agent, a variety of minute breakdown products of the blood corpuscles. Whether the thromboplastic protein exists in circulating blood remains, unfortunately, an inherently unanswerable question.”¹ This statement references what we now recognise as exosomes. Subsequent citations appeared in 1967, describing ‘Platelet Dust’² and 1969 ‘Matrix Vesicles in Bone Calcification’³. In 1978 they were coined ‘Prostosomes’ by Ronquist⁴.

The breakthrough came in 1983 when two independent research teams working on Transferrin formally adopted the term ‘Exosomes’^5,6. Yet it wasn’t until 2012 that the first International Society for Extracellular Vesicles meeting convened in Gothenburg, Sweden — over 65 years post the earliest record in 1946, and in 2025 the field is expanding considerably. This expansion is largely a result of the wide appeal and optimism exosomes will have far reaching applications, somewhat likened to a magic bullet with multitudes of functionalisation capacity to treat cancer, neurodegenerative diseases, impact senescent cells, cosmetics, and regenerative medicines. Given their biogenesis, they offer a snapshot into intercellular life making them terrific candidates for biomarkers. Sounds like they may even wash your car and put your bins out for you.

Clinical Challenges in Exosome Isolation

Exosomes are a particular category of extracellular vesicles (EVs) with a diameter of 30–150 nm. Secreted by most human cells; they serve as mediators of intercellular communication^8,9. However, removing nanoscale contaminants such as cell-free nucleic acids and lipoproteins is difficult and essential for reliable biomarker analysis^7,8. Conventional methods of isolation include Ultracentrifugation (UC), the most common method, Density gradient centrifugation (DGC), Size Exclusion Chromatography (SEC), Ultrafiltration, Field flow fractionation, Precipitation and Microfluidics to name a few, all with varying degrees of capability. Despite this arsenal, limitations in yield (UC is about 40%), integrity, stability, and processing time prevail, which continue to sideline exosomes from widespread clinical adoption.

Technologies like tangential flow filtration (TFF) are popular for isolating exosomes from conditioned cell culture media. However, their clinical adoption faces hurdles due to the high cost of disposable modules, shear stress-induced damage, and large dead volumes that restrict use in diagnostic applications requiring small sample sizes.

Enter EXODUS: An automated isolation system

The aptly named EXODUS system is a novel approach offering high yields (~90%) and exceptional purity (~99%). This flexible system adapts to a wide range of sample types, including urine, plasma, cell culture media, saliva, tears, cerebrospinal fluid (CSF), aqueous humor, bacterial culture media, and even plant samples. It operates label-free using PBS buffer and is remarkably efficient, with lab-scale processing speeds of up to 200 mL/hour and GMP-scale capacities reaching 2 L/hour.

This technology incorporates existing filtration methods but enhances them. According to its developers: “To achieve ultrafast exosome isolation, we designed EXODUS using a dual-filter sample reservoir with two outlets (L, left and R, right), each connected to a nanoporous anodic aluminum oxide (AAO) membrane. Periodic negative pressure oscillations (NPOs) are created on the AAO membrane by switching the direction of negative pressure (NP) and air pressure (AP) (Fig 1a). The periodic NP switching from one side of the device to the other serves two purposes. First, NP applied to the nanoporous membrane allows small particles (such as proteins and nucleic acids) and fluids to pass through, while larger exosomes remain inside the central chamber (Fig. 1a, left). Second, switching NP to AP induces membrane vibrations, promoting resuspension of particles pressed onto the inner membrane surface by fluid flow (Fig 1a, right).”¹⁰

Additionally, the device integrates piezoelectric transducers near the membranes to generate high-frequency harmonic oscillations. Vibration motors induce low-frequency oscillations to further prevent fouling and particle aggregation, maintaining efficient isolation (Fig 1b & 1c).

Fig 1. The hybrid macro- and nanomechanical oscillator-based exosome isolation system: EXODUS. a, The mechanism of NPO (AP, air pressure; NP, negative pressure). b, Photographs of the EXODUS device: 1, cartridge; 2, nanoporous membrane; 3, HF harmonic oscillator; 4, LF harmonic oscillator and 5, outlet (NP to AP switch). Scale bar, 1 cm. c, Schematic diagram of the control module for the resonator of EXODUS. For a larger version, click here.

Conclusion

The EXODUS system is an advanced exosome isolation technology, offering significant improvements in yield, purity, and scalability. By overcoming many of the limitations associated with traditional techniques, EXODUS holds great promise for enabling the widespread clinical and research use of exosomes across numerous fields.

To learn more or secure a demo of the EXODUS system, please contact us.

ATA Scientific Pty Ltd
+61 2 9541 3500
enquiries@atascientific.com.au
www.atascientific.com.au

_{1. E. Chargaff and R. West, “THE BIOLOGICAL SIGNIFICANCE OF THE THROMBOPLASTIC PROTEIN OF BLOOD,” Journal of Biological Chemistry, vol. Volume 166, no. 1, pp. Pages 189-197, 1946.}

_{2. P. Wolf, “The nature and significance of platelet products in human plasma,” British Journal of Haematology, vol. May;13, no. 3, pp. 269-88, 197.}

_{3. H.C. Anderson, “Vesicles associated with calcification in the matrix of epiphyseal cartilage,” Journal of Cell Biology, vol. Apr;41, no. 1, pp. 59-72, 1969.}

_{4. I. Brody, A. Gottfries, B. Stegmayr and G. Ronquist, “An Mg2+ and Ca2+-stimulated adenosine triphosphatase in human prostatic fluid: part I,” Andrologia, Vols. Jul-Aug;10, no. 4, pp. 261-72, 1978.}

_{5. R.M. Johnstone and B.T. Pan, “Fate of the transferrin receptor during maturation of sheep reticulocytes in vitro: selective externalization of the receptor,” Cell, vol. Jul;33, no. 3, pp. 967-78, 1983.}

_{6. J. Heuser, P. Stahl and C. Harding, “Receptor-mediated endocytosis of transferrin and recycling of the transferrin receptor in rat reticulocytes,” Journal of Cell Biology, vol. Aug;97, no. 2, pp. 329-39, 1983.}

_{7. Shuang Du et al., “Extracellular vesicles: a rising star for therapeutics and drug delivery,” Journal of Nanobiotechnology, vol. 21, p. 231, 2023.}

_{8. M.L. Merchant, I.M. Rood, J.K. Deegens and J.B. Lein, “Isolation and characterization of urinary extracellular vesicles: implications for biomarker discovery,” Nature Reviews Nephrology, vol. 13, pp. 731-749, 2017.}

_{9. W. Wang, J. Luo and S. Wang, “Recent Progress in Isolation and Detection of Extracellular Vesicles for Cancer Diagnostics,” Advanced Healthcare Materials, vol. 7, no. 20, p. 1800484, 2018.}

_{10. Y. Chen et al., “Exosome detection via the ultrafast-isolation system: EXODUS,” Nature Methods, vol. 18, pp. 212-218, 2021.}

Top image credit: iStock.com/KS Kim