Antigen Engineering in DNA Immunization

J. A. Wolff and colleagues demonstrated in 1990 (1 ) that naked, non-infectious DNA plasmids can be transferred into muscle cells of living mice to express the encoded protein in vivo. Further studies have shown that proteins expressed in vivo via such a “DNA inoculation” process can serve as immunogens to effectively stimulate the body’s immune system to produce potentially strong, long-lasting, antigen-specific, humoral and cell-mediated immune responses (2 –8 ).