With other collaborators, Vical is also developing DNA vaccines for malaria, Lyme disease, cytomegalovirus, and other conditions. The Phase I trials will test the safety of a potential AIDS vaccine carrying genes that code for noninfectious HIV proteins. Investigators from the University of Pennsylvania and the private biotech firm Apollon Inc. in Malvern, Pa., will conduct the trials. Other researchers also are developing DNA vaccines. One is immunogenicity.
Many vaccines consist of viral surface proteins that provoke an antibody response.
Such antibody-mediated immune responses can be weak. By contrast, DNA vaccines work from the inside of cells, attracting MHC proteins and a potentially stronger cell- mediated response. A virus foils immune system memory, rendering the latest vaccine ineffective. A nucleoprotein that rarely changes. The vaccine should survive influenza's surface mutations.