A recombinant human papillomavirus (HPV) type 16 L1-vaccinia virus murine challenge model demonstrates cell-mediated immunity against HPV virus-like particles

Human papillomavirus (HPV) virus-like particles (VLP) are emerging as the i mmunogen of choice for prophylactic vaccines. The inability to infect anima ls with HPV has prevented the testing of potential vaccines such as these i n animal systems. This study describes the development of a recombinant vac cinia virus (VV)-HPV type 16 (HPV-16) VLP challenge model to evaluate the e fficacy of the cell-mediated immune response following HPV-16 VLP immunizat ion in mice. Inoculation of BALB/c and C57 BL/6 mice with HPV-16 VLP result ed in HPV VLP-specific T cell proliferative responses characterized by the production of both Th, and Th, cytokines, and afforded protection against v irus challenge from recombinant VV expressing HPV-16 L1 (VVL1(R)-16). Prote ction was demonstrated by a 4.6 log(10) reduction in ovarian titres of VVL1 (R)-16 in vaccinated BALB/c mice and a 2.3 log(10) reduction in vaccinated C57 BL/6 mice, compared with unvaccinated mice.