What are mRNA vaccines and how do they work?
Unlike traditional vaccines that use weakened or dead pathogens, mRNA vaccines use a molecule called messenger RNA to teach cells how to produce a viral protein that triggers an immune response.
How mRNA Vaccines Work
Vaccines prepare the body to fight foreign invaders like bacteria or viruses. While most vaccines contain a weakened or dead pathogen, mRNA vaccines use a molecule called messenger RNA (mRNA). Once cells finish making the protein directed by the mRNA, they quickly break down the molecule. This mRNA does not enter the cell nucleus and does not alter DNA.
The process works as follows:
- The vaccine introduces a piece of mRNA that corresponds to a viral protein, typically found on the virus's outer membrane.
- Cells use this mRNA to produce the viral protein.
- The immune system recognizes the protein as foreign and produces specialized proteins called antibodies.
- These antibodies remain in the body, allowing the immune system to quickly recognize and destroy the virus if the person is exposed to it in the future.
Safety and Authorization
Individuals who receive an mRNA vaccine are not exposed to the virus, nor can they become infected with the virus by the vaccine. Like all vaccines in the United States, mRNA vaccines require authorization or approval from the Food and Drug Administration (FDA). Currently, vaccines for COVID-19 are the only authorized or approved mRNA vaccines. These vaccines direct cells to produce copies of the "spike protein" found on the surface of the SARS-CoV-2 coronavirus.