Amino acid motifs in both the major and minor capsid proteins of HPV51 impact antigenicity and infectivity.

Persistent infection with oncogenic Human Papillomavirus (HPV) is a prerequisite for cervical disease development yet data regarding the host immune response to infection at the genotype level are quite limited. We created pseudoviruses bearing the major (L1) and minor (L2) capsid proteins and L1 virus-like particles (VLP) representing the reference sequence and a consensus of thirty-four European sequences of HPV51. Despite the formation of similarly-sized particles, motifs in the reference L1 and L2 genes had a profound impact on the immunogenicity, antigenicity and infectivity of these antigens. The antibody status of women exhibiting low-grade disease was similar between HPV16 and consensus HPV51 but both demonstrated discrepancies between binding and neutralizing antibody responses. These data support the use of pseudoviruses as the preferred target antigen in studies of natural HPV infection and the need to consider variation in both the L1 and L2 proteins for the appropriate presentation of antibody epitopes.