Wikipedia:Main Page history/2021 October 21b

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An mRNA vaccine is a type of vaccine that uses a copy of a molecule known as messenger RNA (mRNA) to produce an immune response. The vaccine transfects molecules of synthetic RNA into dendritic cells, where the vaccine functions as mRNA, causing the cells to build foreign protein that would normally be produced by a pathogen (such as a virus) or by a cancer cell. These protein molecules stimulate an adaptive immune response that teaches the body to identify and destroy the corresponding pathogen or cancer cell. This animated video illustrates how immunization with an mRNA COVID-19 vaccine stimulates an immune response against COVID-19 infection.

Video credit: Swiss Academy of Natural Sciences

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