Infection with Human papillomavirus (HPV) has been reported as one of the most prevalent agent sexually transmitted diseases, but its true prevalence in men is not precisely known, mainly due to the near absence of symptoms. Moreover, few studies evaluating the post-vaccination immune response have been performed to date in men, hence the hypotheses tested in this study can be important to enable a better understanding of both the immunopathogenesis and the response to vaccination in HIV-infected patients, and to help in the elaboration of strategies of vaccination against HPV in the HIV-infected population.