Interview with David Peabody

By Michelle Jung, Communications Editor

Graphic by Madeline Lee

Michelle Jung: Introduce yourself to us and tell us what your role/relation with COVID-19 is.

David Peabody: I am a professor of Molecular Genetics and Microbiology at the University of New Mexico School of Medicine. For many years, I studied the fundamental molecular characteristics of an E. coli virus called MS2. In recent years, however, I have turned my attention to practical applications and with my collaborator, Bryce Chackerian, created a new technological platform for vaccine development based on so-called virus-like particles (or VLPs) of MS2. Since March of 2020, I have been applying the platform to SARS-CoV-2, the virus that causes COVID-19. The MS2 VLP is non-infectious and completely harmless but structurally it looks like a real virus. Evolution has adapted the human immune system to recognize such structures as threatening, so the body produces a strong response to such structures even when, like the MS2 VLP, they are actually harmless. By “decorating” the MS2 VLP with structural bits from other viruses (e.g. SARS-CoV-2) we can produce a vaccine that provokes a strong immune response against those viruses without causing disease.

MJ: How has the pandemic changed your work/life-style? What was it like previously?

DP: In March, I abandoned other work, for the time being, anyway, and began devoting all my efforts to COVID-19. I normally work in the lab all the time anyway, so the general nature of my daily activities hasn’t really changed, but my specific focus has shifted entirely to COVID-19. I have much less direct human contact now because departmental meetings, seminars, etc. are conducted entirely online. The laboratories at my university are open, but with strict limits on how many people can be present together. Masks are mandatory. I am fortunate to live in a state where the governor took the pandemic seriously from the beginning and early on, introduced aggressive measures to limit virus spread.

MJ: Could you possibly describe why COVID-19 impacted the world more severely, becoming a pandemic compared to MERS and SARS, which were both epidemics?

DP: SARS-CoV-2 is less lethal than SARS and MERS but it is more easily transmitted. Many infected individuals shed virus and can infect others even while they themselves show no symptoms. This makes it harder to identify and isolate infected persons and explains why widespread testing and contact tracing are especially important in this pandemic.

MJ: Could you expand on your research and tell us what makes it unique compared to other industrial or research institutes?

DP: Our vaccine technology is different from others you’ve been hearing about. We genetically manipulate so-called virus-like particles (VLPs) of MS2, “decorating” them with bits and pieces taken from structural proteins of SARS-CoV-2. The result is a completely harmless VLP that, in effect, masquerades into the immune system as SARS-CoV-2. The idea is to trick the body into thinking it has been infected with SARS-CoV-2, triggering the immune system to react with a protective response.

MJ: There has been some news about the virus slowly mutating. How are vaccines able to combat some of these mutations?

DP: Fortunately, this particular virus does not mutate very rapidly. Most vaccines in development should elicit a diverse enough immune response that a low level of mutation is unlikely to lead to immune escape. Nevertheless, it would be wrong to say that escape from neutralizing antibodies is not a potential concern.

MJ: Could you possibly give us an estimate on how long it usually takes to develop a vaccine?

DP: Most vaccines spend many years in the basic development phase and sometimes even longer in the clinical trials necessary for final approval and widespread use.

MJ: After a vaccine has been developed, do you think that we will be able to go back to our daily lives without social distancing?

DP: Probably eventually, but this depends on how effective the vaccine is and how widely in the population it is deployed. Only time will tell.

MJ: Could a universal vaccine, similar to flu shots, be created for COVID-19?

DP: Actually, a universal flu vaccine does not yet exist. Influenza virus undergoes constant genetic change so that new strains regularly emerge. This is why it’s necessary to continuously identify emerging strains and produce new flu vaccines every year. A universal vaccine, if one existed, would protect against all past, present and future flu strains.

SARS-CoV-2, on the other hand, is not as mutable as the influenza virus, so a COVID-19 vaccine may not need to be “universal”, at least not in the sense of having to protect against constantly emerging, new SARS-CoV-2 strains. Having said that, however, a truly universal coronavirus vaccine, one that protected against all members of the coronavirus family, would be highly desirable. Not only would it protect us from SARS-CoV-2, but also from other coronaviruses, including any that might emerge in the future.