DNA vaccination of mice with plasmid expressing human papillomavirus 6 major capsid protein L1 elicits type-specific antibodies neutralizing pseudovirions constructed in vitro

Human papillomavirus 6 (HPV 6) causes benign condylomata. As a model For HP V vaccine development, we tested a HPV 6 DNA vaccine candidate, constructed by subcloning the major capsid protein (L1) gene into an expression plasmi d having the cytomegalovirus promoter, for its immunogenicity in BALB/c mic e. Three intracutaneous inoculations of the plasmid with a gene gun at 2-we ek intervals elicited anti-L1 serum antibodies. The antibodies were found t o recognize highly type-specific, conformation-dependent epitopes, includin g those to neutralize pseudovirions capable of inducing beta-galactosidase in infected monkey COS-1 cells. The data support the idea that immunization with DNA capable of expressing HPV L1 can be used as an HPV vaccine strate gy for humans. J. Med. Virol. 60:200-204, 2000. (C) 2000 Wiley-Liss, Inc.