Mystic Aquarium

Immunization using DNA , or nucleic acid vaccination, represents a potentially powerful, effective, and low-risk method for vaccination. Short, circular pieces of DNA called plasmids can be engineered to contain nucleic acid sequences which encode an antigen known to elicit a protective immune response in the host species.

Nucleic acid vaccination induces long-lasting humoral, cellular, and mucosal immunity because protein antigens are directly expressed in their native architecture by host cells. This study employed a reporter gene plasmid containing the gene for ß-galactosidase, an enzyme that bacteria (Escherichia coli) use to split lactose into simple components. A reporter gene plasmid that produces a protein product is foreign to the host but is not pathogenic (does not cause disease). The protein that the gene encodes can be easily assayed for, and thus it "reports" its own expression in the host cell and allows measurement of the immune response. Adult African black-footed penguins were vaccinated and produced measurable amounts of anti-ß-galactosidase antibodies when compared to control animals. Knowledge gained from this work will be integral in the future development of plasmid vaccines against specific infectious diseases of penguins in both captive and wild environments, and potentially of other valuable animal species.