HPV DNA vaccines.

Human papillomaviruses (HPV), particularly HPV type 16, are the primary etiologic agent of cervical cancer. Thus, HPV-associated cervical malignancies might be prevented or treated by induction of the appropriate virus-specific immune responses in patients. HPV capsid proteins including L1 and L2 proteins have been shown to generate neutralizing antibodies against HPV particles in vaccinated individuals. Furthermore, HPV oncogenic proteins such as E6 and E7 proteins are important in the induction and maintenance of cellular transformation and are co-expressed in the majority of HPV-containing carcinomas. They represent ideal targets for the development of therapeutic vaccines against HPV infections and HPV-associated neoplasia. Vaccines targeting these proteins may provide an opportunity to control HPV-associated malignancies. Genetic immunization with naked DNA has emerged as an important strategy for vaccine development. Plasmid DNA encoding antigen of interest, such as capsid protein L1 and L2 (for preventive vaccines) and non-structural proteins E6 and E7 (for therapeutic vaccines) enters the host and stimulates an antigen-specific humoral and cellular immune response. Various strategies to enhance preventive and therapeutic effects of DNA vaccines are currently under active investigation. Should they fulfill their promise, these DNA vaccines may prevent HPV infection or control HPV-related cervical lesions.