Carnegie Mellon Experts Highlight the Promises of mRNA and Vaccinology in Panel Discussion

Ever wondered why mRNA was so important in rapidly producing a vaccine for COVID-19? In a recent panel discussion, two experts from the Mellon College of Science broke down what this molecule is and how it's revolutionized the process of making vaccines.

The session, viewed by more than 1,200 people, kicked off with a presentation from Professor of Physics Markus Deserno, a biological physicist whose research focuses on membranes and proteins. Those two topics turn out to be very important in discussing the coronavirus SARS-CoV-2 that is behind the COVID-19 pandemic and the vaccines that have been developed to ward it off.

"It's a little bit like a Trojan Horse kind of thing," Deserno said of how SARS-CoV-2 infects human cells. With one of the now recognizable spike proteins jutting out of its surface, the virus binds onto a protein on the surface of our cells and essentially tricks the cell into gobbling it up. Once inside, the virus is able to hijack the machinery of a cell and replicate itself many times to send new viral particles out to repeat the process.

Since so much of a virus's life cycle takes place inside our cells, the best place the human immune system can target viruses is when the particles are traveling between cells. However, the immune system is usually slow to learn what to target when fighting off foreign bodies like bacteria and viruses in our bodies.

That's where vaccines come in, Deserno explained. These substances are designed to expose a person's immune system to a disease-causing microbe without actually infecting them. Traditionally, vaccines are made by growing bacterial or viral particles in chicken eggs that can be weakened or inactivated and injected into our bodies to teach our immune systems.

The revolutionary new vaccines work very differently. Messenger RNA, or mRNA, is a molecule that our cells use to transfer instructions from the nucleus to elsewhere in the cells where proteins are made. By giving our cells mRNA instructions on how to make the recognizable spike protein on the surface of SARS-CoV-2, these vaccines trigger our bodies into making the protein and exposing our immune systems to it without exposing them to the full disease.

Compared to the traditional egg route of vaccine development, Deserno pointed out, this new process stands to be far better in several respects, including faster, easier to scale up in production and more flexible. By contrast, mRNA vaccines can be made in test tubes biochemically, and in fact it would even be possible to pre-stage vaccine production facilities with all the raw materials necessary for future pandemics. Scientists would simply need to genetically sequence the disease and could get straight to work on producing the vaccine.

"All of this is only possible at this speed because of decades of fundamental science research," Deserno said. "These developments revolutionize the way we will produce vaccines in the future."

Deserno was joined by Eberly Family Career Development Associate Professor of Biological Sciences N. Luisa Hiller to provide further context on topics such as how mRNA technology could be used for vaccines in the future, and how the COVID-19 mutations that have developed might affect the effectiveness of the vaccines that have been produced.