Potentially Revolutionary Approach to Immunization Uses DNA Vaccine

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Proceedings of the National Academy of Sciences
_October 11, 1994
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Article Highlights
POTENTIALLY REVOLUTIONARY APPROACH TO IMMUNIZATION USES DNA VACCINE
Using a plasmid DNA vaccine for the first time against a non-viral infection, researchers have induced
high levels of antibodies and cytotoxic T lymphocytes against malaria in mice. Encoding the major
surface protein of the malaria sporozoite, this adjuvant-free vaccine protected 68 percent of the
vaccinated mice injected from subsequent infection. Researchers at the Naval Medical Research
Institute, the Pan American Health Organization, and Vical Inc, whose report begins on Page 9866,
ultimately hope to achieve complete protection by preparing a multicomponent DNA vaccine to attack
the malaria parasite at various stages of-its life cycle. At the present time there is no vaccine against
malaria, which is transmitted to humans by mosquitoes and infects 200 million to 500 million people
each year. Vaccines using attenuated malaria parasites have been successful in laboratory tests but
would be impractical in large-scale human immunizations. Use of a plasmid DNA vaccine has the
potential to revolutionize mass immunization because it is inexpensive to make and deliver; it is a dry
powder that can be stored and resuspended before use, and it requires no accompanying ingredient.
This type of DNA vaccine offers the possibility of developing multicomponent vaccines to protect not
only against malaria, but also against other poorly controlled infectious diseases. Risks from this
method of immunization need to be determined, and successful testing in non-human primates must be
demonstrated before trials in humans. For further information, contact Stephen Hoffman at the Naval
Medical Research Institute in Bethesda, Md.; tel. [phone].

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