AN OSPA-BASED DNA VACCINE PROTECTS MICE AGAINST INFECTION WITH BORRELIA-BURGDORFERI

Immunization with recombinant OspA protein of Borrelia burgdorferi pro tects against experimental Lyme disease. In the present study, mice we re injected intramuscularly with plasmid DNA (VR2210) encoding strain B31 OspA. In this vector, the ospA-coding sequence was under transcrip tional control of the cytomegalovirus immediate early promoter. For ne gative and positive controls, mice were immunized with either the plas mid vector without an osp-coding sequence or recombinant OspA protein, respectively. Mice immunized with VR2210 DNA produced OspA-specific a ntibodies that bound to B. burgdorferi in a whole cell ELISA and inhib ited the growth of a homologous strain of B. burgdorferi. Immunization with VR2210 protected mice against challenge with 2 infectious strain s of B. burgdorferi, Sh-2-82 and N40. These results indicate that vacc ination with plasmid DNA expressing OspA is an efficacious method for providing a protective response against B. burgdorferi infection.