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Edit I Buzás: Be always prepared for the unexpected

 Edit I Buzás MD, PhD & DSc

Edit l Buzas

Edit I Buzás is Professor and Chair at Semmelweis University, Department of Genetics, Cell- and Immunobiology, Budapest, Hungary; Head of MTA-SE Immune-Proteogenomics Extracellular Vesicle Research Group, Budapest, Hungary.

Her earlier research at the University of Debrecen (Hungary), Rush University (Chicago, IL, USA) and at McGill University (Montreal, Canada) focused on autoimmunity. She is a laureate of the Carol-Nachman Preis für Rheumatologie (Germany). Since 2006, her research has focused on cell-derived extracellular vesicles. She is Executive Chair of Education of the International Society for Extracellular Vesicles (ISEV), member of the Henry Kunkel Society (Rockefeller University, NYC, USA), organizer of the 2nd ISEV Workshop (on isolation and characterization of extracellular vesicles) in 2013 in Budapest, and Chair of the International Organizing Committee of the 5th Annual Meeting of ISEV in Rotterdam, the Netherlands (2016). She is an Associate Editor of the Journal of Extracellular Vesicles.

 

- Where did you study? What your research group focuses on?

- I started as an immunologist. My original research focused on autoimmunity and T-cell immunology. I worked in this field for rather long until approximately 10 years ago, I came across a manuscript that discussed extracellular vesicles in rheumatoid arthritis and I was fascinated. I thought it was so interesting and exciting that I started to do some research in this direction. At the beginning, when I published something, I added a few extracellular vesicle-related data to the published study. After some time, I discovered that the original stories were interesting; however, the extracellular vesicle parts were the most exciting for me. It did not take too long to make the big decision to start to move in this direction with my group and to study extracellular vesicles as a primary focus of our research. With my colleagues, we had a lot of enthusiasm at this early stage; however, we realized the need for cautiousness because the methodology was not established for isolation and detection of extracellular vesicles. Therefore, we had to try to explore many things by ourselves. This condition made us work quite a bit on standardization and quality control aspects of extracellular vesicles. This is how we understood that for example protein aggregates could interfere with extracellular vesicle detection and isolation. This is something that is now accepted by everyone, but at that time, we had to fight a little bit to convince our colleagues of this fact. We introduced for the first time the differential detergent lysis, which enables us to distinguish vesicles from protein aggregates based on the differential detergent sensitivity of these two different structures. Later we identified additional potential sources of artifacts in extracellular vesicle research. One such potential artifact was that after taking blood, in the blood sampling tube, platelets and blood cells start to release extracellular vesicles. This is one of the reasons why we often overestimate the number of extracellular vesicles in the circulation. We tried to find a solution and found that we can use an anti-coagulant that can prevent this in vitro vesiculation. We demonstrated that 90 minutes after a high fat meal, the number of extracellular vesicle-mimicking chylomicrons is substantially increased in blood plasma samples. In addition, we demonstrated that not only HDL, but also another very common lipoprotein, low-density lipoprotein LDL interferes with extracellular vesicle detection and isolation and it can associate with the surface of extracellular vesicles. We introduced and recently we optimized a simple lipid assay, which alone or in combination with protein or particle number determinations, can be used for standardization of EVs in any laboratories. Finally, as another example, I mention our results showing that extracellular vesicles and cytokines can act in a combinatorial manner, they can synergize or they can even antagonize each other.

Our current research predominantly focuses on extracellular vesicles in cardiovascular diseases.

- What got you first excited about science?

- As I recall, from a very early age I was excited about finding out or “inventing” things. I wanted to become a physicist or an archeologist. In both cases, you would like to discover things. I designed very simple experiments as a small child. What I also remember is the oral part of the entrance examination at medical school. One of examiners told me after the exam “you will be a researcher”. I will never find out what made the examiner tell this prediction which is still ringing in my ears. It turned out that indeed, I never worked as a physician, and I can tell that all my life research gave me a lot of joy. I think it is a unique gift of life to get the opportunity to work in research, to have a chance to learn about the biological processes.

- What has changed in the field over the last 5-10 years?

- I think the first big change was that researchers who previously focused only on specific populations of extracellular vesicles such as cartilage matrix vesicles, or circulating extracellular vesicles (which were at that time referred to as “microparticles”) or on multivesicular body-derived exosomes, they now all understand that EVs represent an important vesicular compartment of the secretome of cells. This is why this unifying concept is a major breakthrough.

I think another major breakthrough was the recognition that EVs do not only serve a narrow set of functions (e.g. “waste disposal” by cells), but they have extremely important and diverse communication or signaling functions. Importantly, it was recognized that RNAs (small RNAs and mRNAs) are carried by EVs. This discovery was a major step in EV research.

The most recent important step was when the scientific community recognized that the EV field urgently requires joint activities and efforts to develop standard procedures of the EV isolation and characterization. MISEV 2018, the multiauthor guideline paper published recently in the Journal of Extracellular Vesicles, is a nice example of how common wisdom and many individual experiences can be joined in a consensus guideline.

- What are the biggest challenges facing your research at the moment?

- I think the biggest challenges for us are still related to methodological limitations. Even though day by day we see some novel developments for extracellular vesicle isolation and detection, not all of them are accessible for the broad extracellular vesicle community. Therefore, I think the most difficult task is to overcome the current technological challenges of extracellular vesicle separation characterization. This is one of the reasons, why it is so important to collaborate with colleagues from different laboratories using different technological platforms.

- Do you have any advice to people starting to work with EVs?

- My first advice is that especially when working in such novel field like the one of EVs, one should never feel sorry for the time invested in running as many controls as possible. This helps to avoid artifacts and the data will be based on solid foundations.

Researchers new to this field, now have an opportunity to “stand on the shoulders” of others, they can go through the recommendations of recent position and guideline papers such as the previously mentioned MISEV 2018 guideline paper.

Like in any research, in the EV field it is very important to have a persistency. We often have to try over and over again, until we solve a problem.

Finally, I would like to add that in the EV field young researchers should be really open-minded, since this is a research area in which many unexpected findings are still come. Therefore, I would encourage researchers entering this field not to limit their imagination and if they have a brave idea, they should go for it. In this novel field, they have a chance to find something really prominent.

- Are there any scientists that you draw inspiration from?

- Besides my mentors, TT Glant and A Falus, in my life many outstanding researchers gave inspiration to me. From among them, I would like to mention Avram Hershko, winner of a Nobel Prize in 2004 for the discovery of ubiquitin-mediated protein degradation who gave me very strong inspiration. His work gave me a real example that even if one works in a field which is not popular at a given time or if there is nobody else working on the same or similar topic, one should trust himself and his data, and go ahead with his work for many years or even for decades. In addition, I think his inspiration “to be always prepared for the unexpected” is particularly important and relevant to extracellular vesicle research.

- What would you say are the major questions still to be tackled in the EV field?

- The big question is whether extracellular vesicles can serve as a next generation therapeutic tools or diagnostic biomarkers. In this field, we all are very hopeful, we all trust that EV-based approaches will have real clinical significance and we work hard for this to happen and to come to reality.