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What are mrna vaccines?
mRNA vaccines work by delivering a single strand of mRNA that provides instructions to human cells to produce a protein. (The role of messenger RNA in the human body is to transport instructions from a gene to the ribosomes that synthesize proteins.) mRNA-based COVID-19 vaccines, for instance, provide instructions to produce just the spike-like protein that the virus uses to enter cells, thereby triggering an immune response. What is relatively new about mRNA is that it is an information molecule that can be designed within days using the virus’ sequenced genome and manufactured synthetically from chemicals (rather than using living cells or chicken eggs). The production process involves coating a single string of mRNA (which is less stable than two-string DNA) in protective fatty lipid nanoparticles, which delay the fragile mRNA strand being broken down by the body’s enzymes. Assuming no changes to the lipid nanoparticle delivery system, new mRNA vaccines can be developed rapidly to address new variants.