Résumé
While single-dose mucosal immunization is best achieved by the use of attenuated live microorganisms, attenuation generally results in decreased immunogenicity. We attenuated
Bordetella pertussis
by the deletion of the pertussis toxin gene. A single intranasal administration of this strain protected against subsequent challenge as well as did the parent strain and better than immunization with commercial vaccine. Unexpectedly, this attenuation resulted in increased immunogenicity against the protective antigen filamentous hemagglutinin (FHA). In addition, immunogenicity was also enhanced against the
Schistosoma mansoni
Sm28GST genetically fused to FHA, resulting in protection against the parasite, as characterized by a reduction in worm burden and egg charge, after a single intranasal administration. Thus, attenuated recombinant
B. pertussis
strains are promising vectors for the simultaneous protection against pertussis and heterologous diseases by a single intranasal administration.