How do nucleic acid vaccines trigger immunity?

DNA plasmid carrying the antigen are usually injected into the muscle, but a key challenge is getting them to cross into people’s cells. This is an essential step, because the machinery which enables the antigen to be translated into protein is located inside cells. Various technology are being developed to aid this process-such as electroporation, where short pulses of electric current are used to create temporary pores in patients’ cell membranes; a ‘gene gun’ which uses helium to propel DNA into skin cells; and encapsulating the DNA in nanoparticles which are designed to fuse with the cell membrane.