mRNA VACCINES

The New Frontier in Synthetic Immunology

by Ben Wilhelm

mRNA Vaccine Technology

mRNA vaccine technology was first developed in the 1980s, but it has only recently been used to develop vaccines that are safe and effective for humans. mRNA vaccines are made by synthesizing a strand of mRNA that encodes for a specific protein. This mRNA is then encapsulated in a lipid nanoparticle (LNP), which protects the mRNA from degradation and helps it to enter cells more efficiently.

Once the LNP enters a cell, the mRNA is released and translated into the desired protein. This protein is then displayed on the surface of the cell, where it can be recognized by the immune system. The immune system then produces antibodies and T cells that are specific to the protein. If the person is ever exposed to the virus or cancer cell again, the immune system will be able to quickly recognize and destroy it.

COVID-19 mRNA Vaccines

The Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines were the first mRNA vaccines to be authorized for emergency use in the United States. These vaccines have been shown to be very effective in preventing serious illness, hospitalization, and death from COVID-19.

Both of these vaccines encode for the spike protein of the SARS-CoV-2 virus. The spike protein is the protein that the virus uses to bind to and enter cells. By encoding for the spike protein, the vaccines teach the immune system to produce antibodies that can block the virus from entering cells.

mRNA Vaccines for Other Diseases

mRNA vaccines are also being developed to protect against a variety of other diseases, including cancer, HIV, malaria, and tuberculosis. Early clinical trials of mRNA vaccines for these diseases have shown promising results.

For example, one mRNA vaccine for cancer, called mRNA-1387, is currently in Phase 3 clinical trials. mRNA-1387 encodes for four different tumor-associated antigens (TAAs). TAAs are proteins that are found on the surface of cancer cells. By encoding for four different TAAs, mRNA-1387 teaches the immune system to produce antibodies that can recognize and destroy a wide range of cancer cells.

Another mRNA vaccine, called mRNA-1644, is currently in Phase 2 clinical trials for HIV. mRNA-1644 encodes for two different HIV proteins. By encoding for two different HIV proteins, mRNA-1644 teaches the immune system to produce antibodies that can recognize and destroy a wide range of HIV strains.

Improvements in Stability and Delivery of mRNA Therapies

One of the challenges of mRNA vaccines is that they are not very stable. mRNA molecules can degrade quickly, especially at room temperature. This makes it difficult to store and transport mRNA vaccines.

Researchers are working to improve the stability of mRNA vaccines by developing new formulations and delivery systems. For example, some researchers are encapsulating mRNA molecules in lipid nanoparticles (LNPs). LNPs protect the mRNA molecules from degradation and help them to enter cells more efficiently.

Another challenge of mRNA vaccines is that they need to be delivered to the right cells in the body in order to be effective. For example, to be effective against COVID-19, mRNA vaccines need to be delivered to the cells that line the respiratory tract.

Researchers are developing new delivery systems that can target mRNA vaccines to specific cells in the body. For example, some researchers are developing mRNA vaccines that can be delivered directly to dendritic cells, which are specialized immune cells that play a key role in initiating an immune response.

Conclusion

mRNA vaccine technology is a promising new approach to vaccine development. mRNA vaccines have the potential to be effective against a wide range of diseases, and they are relatively easy to manufacture at scale. However, there are still some challenges that need to be addressed before mRNA vaccines can be widely used. Researchers are working to improve the stability and delivery of mRNA vaccines, and they are also developing mRNA vaccines for a variety of diseases.

In addition to the challenges mentioned above, there are a few other things that researchers are working on to improve mRNA vaccine technology. For example, they are working on developing mRNA vaccines that can be administered orally or nasally, which would be more convenient than injectable vaccines. They are also working on developing mRNA vaccines that can be used to boost the immune response to other vaccines, such as the measles, mumps, and rubella (MMR) vaccine.

Sources:

Centers for Disease Control and Prevention. "COVID-19 Vaccines." Centers for Disease Control and Prevention, 4 November 2023. Web. 4 November 2023. <https://www.cdc.gov/coronavirus/2019-ncov/vaccines/index.html>.
World Health Organization. "Coronavirus Disease (COVID-19): Vaccines." World Health Organization, 4 November 2023. Web. 4 November 2023. <https://www.who.int/emergencies/diseases/novel-coronavirus-2019/covid-19-vaccines>.
National Institute of Allergy and Infectious Diseases. "Coronavirus Vaccines: Development and Safety." National Institute of Allergy and Infectious Diseases, 4 November 2023. Web. 4 November 2023. <https://www.niaid.nih.gov/diseases-conditions/coronavirus-vaccines-prevention>.
Anderson, Derek R., and Katherine K. Karikó. "mRNA Vaccines for Infectious Diseases." Nature Reviews Drug Discovery, vol. 17, no. 4, 2018, pp. 241–52. PMC, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6189122/. Accessed 4 November 2023.
"Understanding mRNA Vaccine Technology." Science, 17 February 2023. Web. 4 November 2023. <https://medlineplus.gov/genetics/understanding/therapy/mrnavaccines/>.
Weissman, Drew. "mRNA Vaccine Delivery by Lipid Nanoparticles." Cell, vol. 184, no. 4, 2021, pp. 746–61. ScienceDirect, https://doi.org/10.1016/j.cell.2021.01.009. Accessed 4 November 2023.

Visual Sources:

Zoltan, Istvan. “What Is mRNA? The Messenger Molecule That’s Been in Every Living Cell for Billions of Years Is the Key Ingredient in Some COVID-19 Vaccines.” The Conversation, The Conversation Media Group, 7 Dec. 2020, https://theconversation.com/what-is-mrna-the-messenger-molecule-thats-been-in-every-living-cell-for-billions-of-years-is-the-key-ingredient-in-some-covid-19-vaccines-158511. Accessed 1 November 2023.