Washington, March 7 (IANS) There is a hot new approach to developing DNA vaccines against infectious diseases - and these could be fat more potent, says a new study. The innovation behind the idea is that the body subsequently converts the information in the DNA vaccine into a protein that activates an immune response.

Existing DNA vaccines induce rather weak responses even if administered multiple times. New data, generated in mice by Ralph Steinman and colleagues of Rockefeller University identified a way to make them more potent.

In the study, mice were administered a DNA vaccine that included information to make a single protein comprising HIV protein gp41 fused to a single-chain Fv antibody specific for immune cells known as DCs.

These then point out proteins from infectious organisms to immune cells known as T cells that attack the infectious organism.

The new DNA vaccine induced a much stronger T cell response than its previous counterparts, protecting mice more efficiently from a virus engineered to express the HIV protein gp41.

These data led to the suggestion that DNA vaccines might be more potent if the information they contain generates a protein that is targeted to DCs.