In my understanding, the mRNA platform can be used for any application where you want to temporarily express a protein in the body. In the case of these COVID vaccines, it's being used to express the coronavirus spike protein, but Moderna is already using this technology for HIV, flu and others[0]. I believe the applications beyond vaccines are many, too.
It’s pretty much the holy grail for vaccines. It delivers the spike protein via mRNA and the hardest part is the delivery which they’re ironing out with nanolipids (also Moderna biggest IP) during this COVID run. Though I’m an engineer so take everything at face value.
The vaccine only contains the (mRNA) blueprints for the spike protein that cells of the body will then produce themselves. The immune system then reacts to those.
mRNA is a decade in the making, which is why they were able to target/isolate a COVID-19 vaccine is a very short time. Two weeks I believe, someone please correct me.