Published Paper Details:

mRNA - or messenger RNA - vaccines have been a work in progress for several decades, often overshadowed by developments in DNA vaccines due to the safety and efficacy concerns that come with mRNA vaccines. mRNA vaccines function by delivering the coding for an antigen into the host cells. The mRNA is then translated into a protein and processed so that it elicits an immune response. mRNA is a highly favourable vaccination method due to several factors, including the rapid production process, high safety, and non- integrating nature of the mRNA. The three primary struggles of mRNA vaccines are: stability, efficacy, and immunogenicity. These can all be addressed via three highlighted chemical modifications that have shown promise in their ability to improve the functionality of mRNA vaccines. The first modification reduces innate immune sensing upon the reception of an mRNA vaccine by modifying the nucleosides so they are able to bypass the bodies defensive mechanisms and prevent the vaccine from being identified as a threat. Furthermore, 5' cap modifications work as a protective structure that shields RNA from exonuclease cleavage, which is necessary for effective mRNA translation. Lastly, UTR (untranslated regions) and poly(A) tail modifications can extend the lifespan of mRNA and maintains intracellular stability. This literature review aims to summarise the purposes and benefits of these modifications in the future development of mRNA vaccines, and examines the three aforementioned key chemical modifications.