Interaction of human papillomaviruses with the host immune system: a well evolved relationship.

Human papillomavirus (HPV) infections are generally long lasting, and a host immune response to infection is hard to detect. Nevertheless immunocompromised subjects control HPV infection less well than those with intact immunity. Immune responses are best documented for the papillomavirus groups that cause evident human disease, particularly those responsible for anogenital cancers and genital warts. Humoral immunity to the viral capsid has been shown sufficient for protection against infection, while innate and adaptive cell mediated immunity appears important for eventual elimination of HPV infection. However, molecular and cellular mechanisms responsible for protection from and clearance of HPV infection are not completely established.