BY: CAMERON YUEN
Hello! My name is Cameron Yuen, a current senior in high school. I'm going to be attending Tufts University, and I intend on studying Computer Science. I want to use technology to incite change, whether it's bridging the digital divide, aiding public health or bolstering sustainability efforts. Outside of academics, I'm a competitive diver and an avid Overwatch player!
With life being anything but predictable in recent times, the advent of new COVID-19 vaccines only contributes more to the uncertainty. Scientists and doctors are preaching this modern mRNA vaccination method, but what does this even mean? What’s the difference? Is it safe? All questions will be answered, here.
First off, it is important to understand what mRNA even is, and how that relates to vaccination. Short for messenger ribonucleic acid and a pivotal component in our cells’ protein production, it is “the intermediate step between the translation of protein-encoding DNA and the production of proteins by ribosomes in the cytoplasm” (Pardi 262). Essentially, it bridges the encoding and the expression of certain proteins in our cells. This is critical because viruses such as coronavirus contain what is called “spike proteins… [which are] found on the surface of the virus… [and] causes COVID-19” (“Understanding MRNA”).
In the traditional method of vaccination, dead or weak viral particles with the aforementioned spike proteins will be injected into our body for our immune system to recognize as a possible threat. With the spike proteins working as blueprints, our bodies can then use them to produce the appropriate antibodies to stop future infections.
Sinovac, a Chinese-produced vaccine, follows this method by employing dead coronavirus particles. First, they kill the cells with “beta-propiolactone,” removing their ability to replicate, but leaving their spike proteins “in-tact.” From there, the dead cells “are swallowed up by a type of immune cell called an antigen-presenting cell,” which essentially downloads the viral information, and creates the proteins to help destroy the infection (Corum and Zimmer). Although this way is more researched, it also requires far more resources, space, and time. Scientists already know of many viral antigens, but the sampling and replication of “target pathogens or antigens ha[s] to be produced in dedicated cell-cultures and/or fermentation-based manufacturing production processes,” which takes a lot of time and effort (“MRNA Therapeutic Areas”).
The new-age mRNA vaccines like Pfizer and Moderna possess key differences that could revolutionize immunology for years to come. Instead of injecting the viral particles, they contain mRNA that was developed in-vitro, or in a test tube, and coded to stimulate specific protein production in our cells. The mRNA “gives instructions” to our cells on how to produce viral antigen proteins to elicit an antibody-producing immune response, preventing present and future infections. In terms of COVID-19, it helps create a “harmless piece… of the spike protein,” making the injection of viral particles completely unnecessary (“Understanding MRNA”).
But aside from just that, mRNA technology may allow for large-scale improvements over its counterpart in efficacy, discovery, and efficiency. mRNA can be encoded to address many viral proteins in a single dosage of a vaccine to produce more complex antigens which helps fight more complex viruses. This is called “multimeric antigen” production in which proteins with multiple polypeptide chains are created. For example, Moderna’s CMV vaccine has the capability to form a “pentameric protein complex that is a potentially critical antigen for immune protection against CMV” with the power of “six mRNAs” (Corum and Zimmer).
And unlike the traditional method, new ways to experiment with preliminary-stage vaccines are far more simple and expend less with mRNA. Scientists are capable of beginning designs through computer simulations, or “in silico,” which rapidly speeds the production of schematics, “dramatically accelerat[ing]... vaccine selection.” And along with that, traditional vaccines demand “dedicated production processes, facilities, and operators,” while mRNA vaccines’ more consolidated manufacturing can allow for “a single facility” (“MRNA Therapeutic Areas”).
But as promising as this all sounds, it is imperative to remain prudent. Although mRNA research is not new, it only recently has been explored out of the field of oncology. mRNA technology is relatively new to combat viruses like COVID-19, and that raises questions on its effectiveness, as tumor research efforts vastly differ from that of viral ones. As of right now, it is not specifically known if the vaccine will be strong enough to evoke a “sufficiently protective immune response,” or simply “which quantities of mRNA will be needed to [fight viruses]” (“Five Things You Need to Know”). But just like how scientists vigorously tested and refined the traditional method, we’ll eventually reach confidence in our understanding of mRNA vaccines.
Pardi N, Hogan MJ, Porter FW, Weissman D. mRNA vaccines - a new era in vaccinology. Nature reviews. Drug Discovery. 2018 Apr;17(4):261-279. DOI: 10.1038/nrd.2017.243“Understanding MRNA “COVID-19 Vaccines.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/mrna.html.
Corum, Jonathan, and Carl Zimmer. “How the Sinovac Vaccine Works.” The New York Times, The New York Times, 24 Dec. 2020, www.nytimes.com/interactive/2020/health/sinovac-covid-19-vaccine.html.
“MRNA Therapeutic Areas in Infectious Diseases.” Moderna, www.modernatx.com/pipeline/therapeutic-areas/mrna-therapeutic-areas-infectious-diseases.
“Five Things You Need to Know about: mRNA Vaccines.” Horizon, horizon-magazine.eu/article/five-things-you-need-know-about-mrna-vaccines.html.