Combined prophylactic and therapeutic intranasal vaccination against human papillomavirus type-16 using different adeno-associated virus serotype vectors.
BACKGROUND
Cervical cancer is the second most frequent cancer among woman worldwide and is considered to be caused by infection with high-risk papilloma viruses. Genetic immunization using recombinant adeno-associated virus (rAAV) vectors has shown great promise for vaccination against human papillomavirus (HPV) infections.


METHODS
rAAV5, -8 and -9 vectors expressing an HPV16 L1/E7 fusion gene were generated and applied intranasally for combined prophylactic and therapeutic vaccination of mice.


RESULTS
The rAAV5 and the rAAV9 vectors showed efficient induction of both humoral and cellular immune responses, whereas rAAV8 failed to immunize mice by the intranasal route. The L1-specific immune response evoked by expression of the L1/E7 fusion gene, however, was lower than that evoked by expression of the L1 antigen alone. This deficiency could be compensated by application of Escherichia coli heat-labile enterotoxin or monophsphoryl lipid as adjuvant upon vaccination with rAAV5-L1/E7. Coimmunization of rAAV9-L1/E7 with rAAV5-L1 or boosting of rAAV9-L1/E7 with rAAV5-L1 strongly increased L1-specific neutralizing antibody titres to levels above those achieved by vaccination with vectors expressing L1 alone. Both vectors elicited a vibrant cytotoxic T-lymphocyte response against L1 or E7. Nasal immunization with rAAV5 or rAAV9 was superior to vaccination with HPV16-L1 virus-like particles (VLPs) or HPV16-L1/E7 CVLPs with respect to humoral and cellular immune responses. Vaccination with the rAAV vectors led to a significant protection of animals against a challenge with different HPV tumour cell lines.


CONCLUSIONS
Our results show that rAAV5 and rAAV9 vectors are promising candidates for a non-invasive nasal vaccination strategy.
Nieto
Karen
K
Infection and Cancer Research Program, German Cancer Research Center, Heidelberg, Germany.
Kern
Andrea
A
Leuchs
Barbara
B
Gissmann
Lutz
L
Müller
Martin
M
Kleinschmidt
Jürgen A
JA
D000281:Administration, Intranasal; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D000229:Dependovirus / Q000145:classification / Q000235:genetics / Q000276:immunology; D005260:Female; D005822:Genetic Vectors / Q000145:classification / Q000235:genetics; D052162:Human papillomavirus 16 / Q000276:immunology*; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D009856:Oncogene Proteins, Viral / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D050725:Papillomavirus E7 Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D030361:Papillomavirus Infections / Q000188:drug therapy / Q000517:prevention & control / Q000821:virology; D053918:Papillomavirus Vaccines / Q000008:administration & dosage / Q000627:therapeutic use; D012703:Serotyping; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy / Q000517:prevention & control / Q000821:virology; D014611:Vaccination
D000914:Antibodies, Viral; D036022:Capsid Proteins; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines; C063317:L1 protein, Human papillomavirus type 16