The COVID-19 vaccines do all this by delivering information to our muscle cells, usually in our upper arm. They do this in different ways, for example by using mRNA, as Pfizer-BioNTech and Modern, or viral vectors, such as AstraZeneca.
Regardless of technology, the effect is similar. Our cells use the genetic template in the vaccine to produce the coronavirus’ nail protein, which is part of the virus that helps it enter our cells. The nail protein is transported to the surface of the cell where it is detected by the nearby immune cells.
There are also other specialized immune cells nearby, which take up the nail proteins and use them to inform more immune cells-targeted to them specifically against COVID-19.
These immune cells include B cells, which produce antibodies, and T cells, which kill virus-infected cells. They then become long-lasting memory cells, which wait and monitor the next time they see a nail protein.
If you are exposed to the virus, these memory B and T cells allow a faster and greater immune response, which destroys the virus before it can cause disease.
QUICK AND CLEAN
Once they have initiated the immune response, the vaccines themselves are rapidly broken down and cleared from the body.
The MRNA vaccines consist of a fat shell, which encapsulates a group of mRNA particles – the genetic recipe for the nail protein. When this enters a cell, the shell is broken down into harmless fats, and mRNA is used by the cells to produce nail proteins.