DNA VACCINES - A NOVEL-APPROACH TO IMMUNIZATION

Direct DNA inoculations are being developed as a method of subunit vac cination. Plasmid DNAs encoding influenza virus hemagglutinin glycopro teins have been tested for the ability to provide protection against l ethal influenza challenges. In immunization trials using inoculations of purified DNA in saline, 67-95% of test mice and 25-63% of test chic kens were protected against the lethal challenge. Good protection was achieved by intramuscular, intravenous and intradermal injections. In mice, 95% protection was achieved by gene gun delivery of 250-2500 tim es less DNA than the saline inoculations. Successful DNA vaccination b y multiple routes of inoculation and the high efficiency of gene-gun d elivery highlight the potential of this promising new approach to immu nization.