Vaccines teach your body to recognize and fight foreign invaders (viruses), and different vaccines take different paths.
Traditional vaccine
Most vaccines use a weakened or dead version of the actual virus or bacteria.
Arrives
Whole virus particles, inactivated so they cannot replicate.
Engulfed
An immune cell swallows one whole.
Broken down
Enzymes cut it into fragments, called antigens.
Presented
The cell displays those fragments on its surface.
Think of mRNA like a recipe: it gives your cells instructions to build a protein, then breaks down once the job is done.
mRNA VACCINE
mRNA vaccines skip the virus and just deliver genetic instructions.
Arrives
A lipid nanoparticle carries the mRNA to a muscle cell.
Opens
It releases the mRNA into the cell, not the nucleus.
Translated
Ribosomes read it and build one viral protein.
Cleared out
Enzymes break the mRNA down within days. The protein stays.
Either path ends here
Your immune system spots it as foreign, builds antibodies, then files it away for the future, so if the real virus shows up later, it's got a playbook.