On October 2, 2023, the Nobel Committee unveiled the recipients of the Nobel Prize in Medicine, recognizing the groundbreaking work of Hungarian biochemist Katalin Kariko and American immunologist Drew Weisman. Their revolutionary discoveries paved the way for the development of highly effective mRNA vaccines against COVID-19.
A New Approach to Vaccines
Traditionally, vaccines have been developed using weakened or inactivated viruses to stimulate the immune system. However, this approach is often time-consuming and resource-intensive. Kariko and Weisman explored an innovative method that relied on the genetic code of the virus instead of the virus itself. They focused on utilizing proteins based on specific genetic sequences from the virus to trigger antibody production, effectively blocking the virus.
This novel approach had a significant advantage: it didn’t require large-scale cell cultures, making it more adaptable during outbreaks and pandemics.
The Role of Modified mRNA
The key breakthrough by Kariko and Weisman came in the form of modified mRNA (messenger RNA). Messenger RNA is responsible for transmitting genetic information encoded in DNA to produce proteins. In the 1980s, they discovered that by modifying the bases of mRNA, they could enhance protein production while minimizing inflammatory responses.
Traditional mRNA synthesis was considered unstable, challenging to deliver, and could lead to inflammatory reactions. Kariko and Weisman’s research pinpointed the role of dendritic cells, which are immune system helper cells, in recognizing transcribed mRNA as a foreign substance, triggering inflammatory responses.
To address this, they experimented with various mRNA variants, introducing unique chemical modifications to the bases. The result was a significant reduction in inflammatory reactions, a discovery they made in 2005. Further research in 2008 and 2010 confirmed that modified mRNA could substantially boost protein production by reducing the activity of enzymes that regulate protein synthesis.
Translating Science into Action
The practical application of Kariko and Weisman’s groundbreaking work arrived in 2020 when pharmaceutical companies Pfizer and Moderna utilized this technology to develop mRNA vaccines against the SARS-CoV-2 virus, which causes COVID-19.
Beyond COVID-19: A New Era in Vaccines
The Nobel Committee hailed Kariko and Weisman’s contributions as a game-changer in addressing one of the most significant health crises in recent history.