Analysis: here's a guide to the full list of ingredients in the Pfizer/BioNTech vaccine and what each one does At first glance, the chemical names of the components in the vaccine do sound rather ominous, so let's break them down one by one. (1) mRNA The most important ingredient is mRNA (messenger ribonucleic acid).
We can view it as a messenger delivering a message (genetic sequence of the spike protein of SARS-CoV-2) to our immune cells thereby eliciting an immune response.
What's extraordinary about mRNA vaccines is that they contain no actual part of the virus. It’s only the instructions on how to make the spike protein so you can’t get infected with Covid from the vaccine.