News and Research
Immune System

Bacterial Viruses Make Cheap Easy Vaccines

3-10-2003 BALTIMORE Genetically altered bacterial viruses appear to be more effective than naked DNA in eliciting an immune response and could be a new strategy for a next generation of vaccines that are easy to produce and store, say researchers from Moredun Research Institute in the United Kingdom.

"In theory, millions of doses can be grown within a matter of days using simple equipment, media and procedures," says John March, one of lead researchers presenting findings on the immune response at the American Society for Microbiology's Biodefense Research Meeting.

Bacteriophages are viruses that infect bacteria but not humans. In this particular study, March and his colleagues used a bacteriophage as a vehicle for genes from hepatitis B virus in mice and compared its ability to elicit a protective immune response with a vaccine made of naked DNA. They found that not only could the bacteriophage induce an immune response, the number of bacteriophage they needed was less than 1 percent of the number of pieces of naked DNA required to mount an effective immune response.

Using bacteriophages to deliver vaccine components offers several advantages over vaccination with naked DNA, says March. The DNA is protected inside the protein shell of the virus making it longer lasting and easier to store. In addition, bacteriophages have a large cloning capacity, making large-scale production cheap, easy and extremely rapid – important attributes considering the current bioterrorism threat when sudden demands may be placed on vaccine stocks.