Hepatitis B surface antigen fusions delivered by DNA vaccination elicit CTL responses to human papillomavirus oncoproteins associated with tumor protection

We describe the construction and evaluation of a recombinant hepatitis B surface antigen (HBsAg)-vectored DNA vaccine encoding the E7 and E6 tumor-associated oncoproteins of human papillomavirus (HPV) type 16. We show the induction of effector and memory cytotoxic T lymphocyte responses to E7 and E6 class I-restricted epitopes after a single immunization, which were associated with tumor prevention and therapy. The findings vindicate the use of a HBsAg-based DNA vaccine as a vehicle to elicit responses to co-encoded tumor antigens, and have specific implications for the development of a therapeutic vaccine for HPV-associated squamous carcinomas