Abstract
In this Q&A, Scientific Editor Emily Marcinkevicius talks to co-first authors Abraham J. Qavi and Krista Meserve and corresponding author Gaya K. Amarasinghe about their paper “Rapid detection of an Ebola biomarker with optical microring resonators.” The project’s success depended on cross-lab relationships and collaborations across academia, industry, and government.
Gaya K. Amarasinghe
Department of Pathology and Immunology, Washington University School of Medicine
Abraham J. Qavi
Department of Pathology and Immunology, Washington University School of Medicine
Krista Meserve
Department of Chemistry, University of Michigan
Main text
The Ebola virus is a highly infectious pathogen with reported mortality rates of up to 89%. Previous Ebola virus outbreaks and the ongoing global COVID-19 pandemic have highlighted, with devastating clarity, the importance of rapid, sensitive strategies for pathogen detection. To address this need, Qavi, Meserve, et al. have developed a new method for the quantitative detection of Ebola secreted glycoprotein (sGP) using optical microring resonators. In under 40 minutes, the assay returns quantitative levels of sGP that may be used for both diagnosis and assessing prognosis. The assay also has a high multiplexing capacity, which can allow for differential diagnosis against other viruses with similar clinical presentation or potentially other prognostic biomarkers. These attributes can enable strategic outbreak management in resource-limited settings.
First, please tell us a little bit about yourselves. Where are you from, what motivated you to become a scientist, and what is your current position and research focus?
Krista Meserve: I am originally from the rural, small town of Hollis, Maine. I attended Emmanuel College in Boston, Massachusetts as a first-generation college student, where I earned my BS in chemistry. I then stayed in the city to work at a small biotech company for a year post grad. I am currently a third year PhD Candidate at the University of Michigan working with Professor Ryan Bailey. I chose his research group because I was interested in using the lab’s sensor platform to push forward applications in a clinical space. I originally pursued chemistry because of forensic science tv shows. However, once I was in college and participated in undergrad analytical chemistry research, I was hooked on optimizing experiments, controlling variables, and solving problems!
Abraham J. Qavi: I grew up in Southern California and completed my undergraduate studies at the University of California, Irvine. During this time, I was introduced to research throughout my freshman chemistry courses and have been hooked ever since! Following my undergraduate studies, I matriculated in the Medical Scholars Program at the University of Illinois at Urbana-Champaign, where I completed my PhD under the mentorship of Professor Ryan Bailey. Krista and I are thus from the same academic family tree!
The ability to create and engineer solutions to difficult problems has fascinated me, and as a scientist, I’m faced with new and interesting problems on a daily basis. I am currently part of the Physician Scientist Training Program with the Department of Pathology & Immunology at Washington University in St. Louis. My research interests focus on the development of new diagnostics for emerging and re-emerging diseases.
Gaya K. Amarasinghe: I grew up in Sri Lanka and got interested in science during middle and high school. As a freshman studying at City College of New York, I had an opportunity to work in a laboratory at Rockefeller University and never left the lab. I conducted my graduate training with Professor Michael Summers at University of Maryland Baltimore County and completed my postdoctoral training with Professor Michael Rosen at UT Southwestern Medical Center. I began my independent academic career at Iowa State University and moved to St. Louis in 2011. Currently, I am a Professor in the Pathology and Immunology Department at the Washington University School of Medicine in St Louis. My main research interests are to understand the physical basis for normal and pathologic events at the host-microbial interface.
Thank you! So, for the uninitiated, please tell us what on Earth is an optical microring resonator?
A.J.Q.: This is a type of device where light is confined within a relatively small volume. In many types of optical sensors, light goes in, interacts with a sample, and then goes into a detector. Because we are confining light within a small structure, our sensors have many more opportunities for the light to interact with the samples, thereby increasing the analytical sensitivity.
We make use of optical resonance, the idea that two waves in phase with each other can be combined to form a wave with a larger amplitude. Any binding of an analyte to the surface of the microrings will change the local optical environment and, in turn, change the conditions needed for resonance. By monitoring these changes, we can quantitatively detect binding events.
In short, these are devices where we can confine light, have it interact many times with analytes on the sensor surface, and use this to make a highly sensitive device.
What was the motivation for applying this technology to Ebola detection?
A.J.Q.: As a clinical pathologist, diagnostics are always in the forefront of my mind. The ability to diagnose infection faster and provide a diagnostic for a critical gap in the context of Ebola virus fascinated me.
G.K.A.: We have a history of working with proteins from Ebola virus and Marburg virus and evaluating the impact of these protein in collaboration with BSL4 groups. When Abe came up with the idea of using this platform for pathogen detection, I immediately thought of Ebola virus, since one form of the viral glycoprotein is secreted (called sGP). Javad Aman at Integrated Biotherapeutics (another collaborator on several of our current projects) and Jon Dye at USAMRIID had already collected samples and looked at sGP as a potential biomarker. Our collaborative network and the willingness of the collaborators to share reagents and materials was therefore a key, driving force for our study.
This sounds like it was a truly collaborative project. Abe and Krista, please tell us more about working together and with your other key collaborators
A.J.Q.: I could not have asked for better collaborators and colleagues than Krista and Ryan Bailey. Krista helped drive the project and was always catalyzing discussions within the design of experiments. It was a fantastic experience being able to work with Ryan, my former PhD advisor, again but now as a more seasoned scientist and also having had experience as a physician.
Our larger network of collaborators—Integrated Biotherapeutics, Mapp Biopharmaceutical, USANCA, and USAMRIID—was instrumental in this work. Big science, especially in the context of highly infectious diseases, requires a highly collaborative group of researchers to pool together their efforts. Without all of our collaborators, this work would not have been possible.
K.M.: Working with Abe and Gaya on this project has been great! I’ve appreciated their mentorship and guidance through the experimental design and writing up of our paper. I’m excited to be a part of the first multi-generational Bailey Lab project. Abe was an author on the lab's first papers that I studied for my candidacy exam, so getting to collaborate with him was pretty cool.
In addition to the collaborators mentioned by Abe, another important partner we had was Genalyte, Inc., which along with the Bailey Group co-developed and commercialized the microring sensor platform (Matchbox) and silicon sensor chips that we used for sGP detection in this study.
What were some of the major challenges you encountered with the project, and how did you overcome them together?
K.M.: For the assay development, the original experiments focused on unlabeled detection. However, it was clear this method was unsuitable for identification of this target in a biologic matrix. We then worked with Integrated Biotherapeutics to get a secondary antibody, which allowed us to employ the amplification assay that we have been using in our lab to detect the target with low limits of detection.
A.J.Q.: One major challenge we faced early on in the project dealt with the sensor design. We had initially invested a significant amount of time into a sensor design that unfortunately did not pan out. Switching from this to the microring format (used in our paper) was difficult at first given our previous time and efforts. However, once we had made the switch to microring sensors, the science moved much faster. Another major challenge we faced was bringing together so many collaborators on this project. We all come from very different scientific backgrounds, but each of the components our collaborators provided was critical in the execution of the project. Bridging our complementary areas of expertise and communicating our science was challenging but highly rewarding!
What are the ways that you think this method can be transformative?
A.J.Q.: This method is transformative in several ways. For one, the biomarker used in our study provides both a diagnostic and prognostic marker for Ebola virus infection. Diagnostic information can better enable healthcare providers to proactively treat and isolate patients infected with Ebola virus. Prognostic capabilities of this biomarker suggest that we can better treat patients with poor prognosis, allocating critically limited healthcare resources to those who need them most. From a technology standpoint, our method highlights the utility of high-sensitivity optical technologies in the diagnostic space. While our method focuses on Ebola virus, we have built a framework that can enable the sensitive, rapid detection of a variety of disease states.
G.K.A.: There are two key aspects of this work. One, having the right tools and access to samples for the filovirus project allowed us to not only validate the technology, but ask a potentially lifesaving question because the results from our studies show both diagnostic and prognostic values. Second, we realized that the platform can be adapted to sensing other types of pathogens and the method is not limited to viruses. With the gain in sensitivity and the ability to multiplex, there’s really no limit to what we may be able to detect.
Let’s look forward together. What is next for each of you, professionally?
K.M.: In my remaining couple of years in the Bailey Lab, I’ll continue using the microring resonator sensors to characterize biomarkers of the immune systems in varying disease populations. After graduate school … I’m keeping my options open!
A.J.Q.: Professionally, I will be moving onto an independent career as a physician scientist in clinical pathology. My hope is to continue work in the diagnostic space, marrying new technologies with critical needs in disease diagnosis.
G.K.A.: In terms of pathogen detection, this work has opened the door for us to think about developing highly sensitive assays. Given the diversity of expertise and resources from IBT (private industry), USAMRIID (government), and WUSM/UM (academic), this was a perfect collaboration. Looking ahead, I expect this project to launch Abe into his own independent research career. Having experienced this work and the effectiveness of collaborative science, I also expect that this experience will inform career decisions for Krista.
In your specific field(s) of research, what do you see as the major technological hurdles that you hope or anticipate will be addressed with new methods?
A.J.Q.: Access to field deployable devices is a major hurdle in the diagnostic space. There has been a plethora of highly sensitive detection techniques that require a centralized laboratory. Being able to miniaturize and deploy these devices to the field is still a major hurdle. With the continued development of embedded systems and smaller optical components, I believe that this hurdle can be addressed in the near future.
How do you like to spend time together with your lab, and how do you celebrate milestones?
K.M.: In the Bailey Lab, we usually celebrate accomplishments with tacos! Outside of lab we have gone kayaking and blueberry picking and have held many group gatherings in the summer or around the holidays.
A.J.Q.: In the Amarasinghe lab, we regularly have dinner potlucks together where members of the group will get together and cook for each other. Being able to relax, throw on an apron, and connect with our lab-mates in an informal setting has become a great way to connect. Another one of our cherished traditions is grabbing coffee after a successful paper or just because (courtesy of Gaya, of course!).
G.K.A.: We celebrate little things and big things alike, mostly with coffee and food. The last 2 years, it has been difficult to get together, so we’ve resorted to things like Zoom painting and Zoom coffee. But this is changing to in-person activities, and I am optimistic that we can continue these in-person events in the future.
What advice do you have for more junior scientists than yourselves who are embarking on a new career phase or project?
K.M.: While I’m probably considered the junior scientist here, I’d encourage undergraduate scientists to engage in a research project where they can determine if they can see themselves conducting research as a career. I wouldn’t be here without my experience in undergrad research!
A.J.Q.: Celebrate the small victories! Given how unpredictable and arduous science can be, celebrations help us reflect on our hard work and accomplishments.
G.K.A.: I think this paper is a good example of how collaborative work and good communication can lead to exciting results. Working with Abe, Krista, Lan, and Ryan, we could have shown that the technology can work, but samples and reagents from IBT and USAMRIID really allowed us to do something unique. So, learning how to ask for help and giving the collaborators credit for their contributions is something that I think is important for junior colleagues to think about when starting a new project.