The DNA vaccine expresses and secretes detoxified E7 fused to HSP70 to enhance dendritic-cell uptake and cross-presentation, priming HPV16 E7–specific CD8+ T cells. These CTLs then kill HPV16 E7–expressing tumor/infected cells via MHC I recognition and perforin/granzyme; the detoxified E7 itself is an immunogen, not a direct cytotoxic target.