Purification and immunogenicity study of human papillomavirus type 16 L1 protein in Saccharomyces cerevisiae.
Human papillomavirus 16 virus-like particle (HPV16 VLP) vaccines expressed in Saccharomyces cerevisiae are under Phase III trial and are expected to be on the market in the near future. We have established a convenient and economical system for the prophylactic study of vaccines derived from HPV16 VLPs, and neutralization tests to standardize HPV serological methodology as a measure of validation. To purify HPV16 VLPs, yeast cells expressing HPV16 L1 protein were cultured and purified on a small scale by ultracentrifugation and size-exclusion and cation-exchange chromatography using open columns. The highly purified HPV16 L1 protein was identified by SDS-PAGE and Western blotting, and electron microscopic analysis confirmed that they self-assembled into VLPs. To test the efficacy of the purified VLPs as a vaccine and their ability to induce humoral immunity, we performed ELISA assays and observed a significant increase in the titer of anti-HPV16 VLPs antibodies in the sera of immunized mice. High anti-HPV16 neutralizing titers were found in the sera of vaccinated mice, as measured by a SEAP-based pseudovirus neutralization assay. These results would be useful in the evaluation of the immunogenicity of HPV vaccine candidates, and provide an international reference standard for HPV serological methods.
Kim
Se Na
SN
College of Pharmacy, Chung Ang University, 221 Huksuk-Dong, Dongjak-Ku, Seoul 156-756, Republic of Korea.
Jeong
Hye Sung
HS
Park
Sue Nie
SN
Kim
Hong-Jin
HJ
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D036022:Capsid Proteins / Q000276:immunology* / Q000302:isolation & purification*; D005260:Female; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D009856:Oncogene Proteins, Viral / Q000276:immunology* / Q000302:isolation & purification*; D053918:Papillomavirus Vaccines / Q000276:immunology* / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000276:immunology / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014614:Vaccines, Synthetic / Q000276:immunology* / Q000302:isolation & purification; D014771:Virion / Q000276:immunology
D000914:Antibodies, Viral; D036022:Capsid Proteins; D009856:Oncogene Proteins, Viral; D053918:Papillomavirus Vaccines; D011994:Recombinant Proteins; D014614:Vaccines, Synthetic; C063317:L1 protein, Human papillomavirus type 16