HUMAN-PAPILLOMAVIRUS TYPE-11 RECOMBINANT L1 CAPSOMERES INDUCE VIRUS-NEUTRALIZING ANTIBODIES

The human papillomavirus type 11 (HPV-11) L1 major capsid protein can be trypsinized to generate recombinant capsomeres that retain HPV geno type-restricted capsid antigenicity (M. Li, T. P. Gripe, P. A. Estes, M. K. Lyon, R. C. Rose, and R. L. Garcea, J. Virol. 71:2988-2995, 1997 ), In the present study, HPV-11 virion-neutralizing monoclonal antibod ies H11.F1 and H11.H3, previously characterized as recognizing two dis tinct HPV-11 capsid-neutralizing antigenic domains (S. W. Ludmerer, D. Benincasa, and G. E. Mark III, J. Virol, 70:4791-4794, 1996), were ea ch found to be highly immunoreactive with trypsin-generated capsomeres in an enzyme-linked immunosorbent assay (ELISA), Capsomeres were used to generate high-titer polyclonal immune sera that demonstrated HPV g enotype-restricted reactivity by ELISA, The capsomere antisera were th en tested in an in vitro infectivity assay and found to neutralize HPV -11 virions. In this assay, HPV-11 capsomere polyclonal antisera exhib ited neutralization titers (10(-5) to 10(-6)) comparable to those obta ined with a virion-neutralizing antiserum raised previously against in tact HPV-11 VLPs (R. C. Rose, R. C. Reichman, and W. Bonnez, J. Gen, V irol. 75:2075-2079, 1994), These results indicate that highly immunoge nic, genotype-restricted HPV capsid-neutralizing antigenic domains are contained entirely within capsomeres. Thus, capsomeres may be viable vaccine candidates for the prevention of HPV disease.