DNA vaccines are a promising advancement in vaccine technology where genes of interest (antigens) are identified and cloned into plasmids. The plasmid carries essential elements like a promoter site, cloning site, origin of replication, selectable marker sequence, and a terminator sequence such as a poly-A tail.

For administration, the DNA is directly injected into the muscles, often using a 'gene gun' based on compressed gas, or through a nasal spray. The antigenic DNA is taken up by muscle cells, leading to protein expression that induces the immune system. These vaccines are effective because they induce both humoral and cellular immune responses.