Expression and characterization of cholera toxin B-pneumococcal surface adhesin A fusion protein in Escherichia coli: ability of CTB-PsaA to induce humoral immune response in mice.

Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 09/2004; 321(1):192-6. DOI: 10.1016/j.bbrc.2004.06.118
Source: PubMed

ABSTRACT Cholera toxin B subunit (CTB) is responsible for CT holotoxin binding to the cell and has been described as a mucosal adjuvant for vaccines. In this work, the ctxB gene was genetically fused to the psaA gene from Streptococcus pneumoniae, a surface protein involved in its colonization in the host that is also considered a vaccine antigen candidate against this pathogen. The CTB-PsaA fusion protein was expressed in Escherichia coli, and the purified protein was used for intranasal immunization experiments in Balb/C mice. CTB-PsaA was able to induce both systemic and mucosal antibodies evaluated in serum, saliva, and in nasal and bronchial wash samples, showing that CTB-PsaA is a promising molecule to be investigated as S. pneumoniae vaccine antigen candidate.

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