Nanoparticle Tracking Analysis Used to Study Exosomes and Microvesicles Behaviour 

NanoSight ltd. (UK) reports on how Nanoparticle Tracking Analysis, NTA, is being used to study extracellular vesicles in the research laboratories of Dr Gregory Gores of the Mayo Clinic in Rochester, Minnesota.

The Gores Laboratory of the Mayo Clinic does basic research into liver disease. One of the main research areas of interest is lipotoxicity and its role in development of nonalcoholic steatohepatitis, a common feature of metabolic syndrome or obesity. The group has developed the hypothesis that lipotoxicity induces the release of extracellular vesicles (exosomes and microvesicles) from the liver cells. They speculate that these extracellular vesicles are involved in immune cell recruitment and activation, resulting in liver inflammation.

Choosing NTA enables Dr Gores' team to precisely measure the size distribution and quantity of the extracellular vesicles in samples. This is a crucial requirement of their research. With NTA technology, they are also able to measure vesicles immediately after their isolation, which allows their use at defined concentrations in subsequent experiments the very same day.

Prior to using the NanoSight system, the Group has used scanning electron microscopy to visualise and measure size of particles and basic absorbance to measure protein amount for inaccurate measurements of vesicle numbers. Since having NanoSight NS300 instrument, they only use NTA to measure size distribution and quantity of their vesicles.

Speaking about the NS300, research fellow, Dr Petra Hirsova, said: "There really is no comparison with other techniques; being able to see, count and measure size of the particles in real time is a huge advantage over other techniques that we have used. Compared to scanning electron microscopy, preparing the sample and obtaining the results is much easier and faster with NTA. NTA provides a much more precise assessment of extracellular vesicle amount compared to measurement of total protein of the vesicles."