Enhanced T cell-mediated protection against malaria in human challenges by using the recombinant poxviruses FP9 and modified vaccinia virus Ankara
Abstract
Malaria is a major global health problem for which an effective vaccine is required urgently. Prime-boost vaccination regimes involving plasmid DNA and recombinant modified vaccinia virus Ankara-encoding liver-stage malaria antigens have been shown to be powerfully immunogenic for T cells and capable of inducing partial protection against experimental malaria challenge in humans, manifested as a delay in time to patent parasitemia. Here, we report that substitution of plasmid DNA as the priming vector with a specific attenuated recombinant fowlpox virus, FP9, vaccine in such prime-boost regimes can elicit complete sterile protection that can last for 20 months. Protection at 20 months was associated with persisting memory but not effector T cell responses. The protective efficacy of various immunization regimes correlated with the magnitude of induced immune responses, supporting the strategy of maximizing durable T cell immunogenicity to develop more effective liver-stage vaccines against Plasmodium falciparum malaria.
- Publication:
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Proceedings of the National Academy of Science
- Pub Date:
- March 2005
- DOI:
- 10.1073/pnas.0406381102
- Bibcode:
- 2005PNAS..102.4836W
- Keywords:
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- MEDICAL SCIENCES