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Structure-based approach to rationally design a chimeric protein for an effective vaccine against Group B Streptococcus infections.

ABSTRACT: Structural vaccinology is an emerging strategy for the rational design of vaccine candidates. We successfully applied structural vaccinology to design a fully synthetic protein with multivalent protection activity. In Group B Streptococcus, cell-surface pili have aroused great interest because of their direct roles in virulence and importance as protective antigens. The backbone subunit of type 2a pilus (BP-2a) is present in six immunogenically different but structurally similar variants. We determined the 3D structure of one of the variants, and experimentally demonstrated that protective antibodies specifically recognize one of the four domains that comprise the protein. We therefore constructed a synthetic protein constituted by the protective domain of each one of the six variants and showed that the chimeric protein protects mice against the challenge with all of the type 2a pilus-carrying strains. This work demonstrates the power of structural vaccinology and will facilitate the development of an optimized, broadly protective pilus-based vaccine against Group B Streptococcus by combining the uniquely generated chimeric protein with protective pilin subunits from two other previously identified pilus types. In addition, this work describes a template procedure that can be followed to develop vaccines against other bacterial pathogens.

SUBMITTER: Nuccitelli A

PROVIDER: S-EPMC3121859 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Structure-based approach to rationally design a chimeric protein for an effective vaccine against Group B Streptococcus infections.

Nuccitelli Annalisa A Cozzi Roberta R Gourlay Louise J LJ Donnarumma Danilo D Necchi Francesca F Norais Nathalie N Telford John L JL Rappuoli Rino R Bolognesi Martino M Maione Domenico D Grandi Guido G Rinaudo C Daniela CD

Proceedings of the National Academy of Sciences of the United States of America 20110518 25

Structural vaccinology is an emerging strategy for the rational design of vaccine candidates. We successfully applied structural vaccinology to design a fully synthetic protein with multivalent protection activity. In Group B Streptococcus, cell-surface pili have aroused great interest because of their direct roles in virulence and importance as protective antigens. The backbone subunit of type 2a pilus (BP-2a) is present in six immunogenically different but structurally similar variants. We det ...[more]

PMID: 21593422

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Structure-based approach to rationally design a chimeric protein for an effective vaccine against Group B Streptococcus infections.

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Structure-based approach to rationally design a chimeric protein for an effective vaccine against Group B Streptococcus infections.

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