Human Papillomavirus Vaccine: State of the Art and Future Perspectives

Human Papillomavirus (HPV) is a widely distributed and common virus, that causes benign lesions (such as warts and papillomas) but, if not cleared, can lead to malignant lesions as well, such as intraepithelial lesions and neoplasia. An extensive body of researches has demonstrated that E1 and E2 are involved in viral transcription and replication, E5, E6, and E7 act as oncoproteins, whilst L1 and L2 contribute to the formation of the capsid. However, this view has been recently challenged, since also E2 could play a role in HPV-induced carcinogenesis. Therefore, a complex picture is emerging, opening new ways and perspectives. The present article provides an overview of the biology of HPV, paying particular attention to its structural details and molecular mechanisms. The article also shows how this knowledge has been exploited for developing effective vaccines, both prophilactic/preventive and therapeutic ones. L1-based prophylactic vaccines, like Gardasil, Cervarix, and Gardasil 9, have been already licensed, whilst L2-based second generation preventive vaccines are still under clinical trials. New, highly immunogenic and effective vaccines can be further developed thanks to computer-aided design and bioinformatics/computational biology. The optimization of combinational therapies is another promising opportunity.