Papillomaviruses: prophylactic vaccine prospects

Identification of a subset of HPV types as etiologic agents of cervical cancer and other malignancies implies that development of an effective vaccine against HPV infection could have a major impact on tumors attributable to these viruses. The ability of the L1 major capsid protein of papillomaviruses to self-assemble into VLPs that can, when inoculated systemically, induce high levels of neutralizing antibodies and protect animals against experimental viral challenge makes L1 VLPs an excellent candidate subunit vaccine. VLPs have the limitation of inducing type- specific immunity. Studies in humans are required to determine whether systemic vaccination with L1 VLPs will prevent sexually transmitted HPV infection. Since prospective efficacy trials will take several years to complete, considering alternative approaches is also worthwhile.