Although specific time is not yet clear, the coronavirus mRNA vaccine is expected to be degraded within hours after translation, according to Rebecca Dutch, Ph.D., a virologist at the University of Kentucky.
"It’s unclear how long this degradation takes. With regular mRNA, it’s within hours. The special coating involved with mRNA coronavirus vaccines may make this take a bit longer, but how much longer is uncertain."
After entry into the cell, the LNP coated mRNA is taken to endosome, where mRNA undergoes endosomal escape and enters the cytoplasm. Eventually, LNP will be trafficked to and enzymatically degraded in lysosome, or secreted from the cell via exocytosis.
Pardi, N., Hogan, M., Porter, F. et al. mRNA vaccines — a new era in vaccinology. Nat Rev Drug Discov 17, 261–279 (2018). https://doi.org/10.1038/nrd.2017.243
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