Construction and Characterization of a Live, Attenuated aroA Deletion Mutant of Pseudomonas aeruginosa as a Candidate Intranasal Vaccine
AUTOR(ES)
Priebe, Gregory P.
FONTE
American Society for Microbiology
RESUMO
Antibodies to the lipopolysaccharide O antigen of Pseudomonas aeruginosa mediate high-level immunity, but protective epitopes have proven to be poorly immunogenic, while nonprotective or minimally protective O-antigen epitopes often elicit the best immune responses. With the goal of developing a broadly protective P. aeruginosa vaccine, we used a gene replacement system based on the Flp recombinase to construct an unmarked aroA deletion mutant of the P. aeruginosa serogroup O2/O5 strain PAO1. The resultant aroA deletion mutant of PAO1 is designated PAO1ΔaroA. The aroA deletion was confirmed by both PCR and failure of the mutant to grow on minimal media lacking aromatic amino acids. When evaluated for safety and immunogenicity in mice, PAO1ΔaroA could be applied either intranasally or intraperitoneally at doses up to 5 × 109 CFU per mouse without adverse effects. No dissemination of PAO1ΔaroA to blood, liver, or spleen was detected after intranasal application, and histological evidence of pneumonia was minimal. Intranasal immunization of mice and rabbits elicited high titers of immunoglobulin G to whole bacterial cells and to heat-stable bacterial antigens of all seven prototypic P. aeruginosa serogroup O2/O5 strains. The mouse antisera mediated potent phagocytic killing of most of the prototypic serogroup O2/O5 strains, while the rabbit antisera mediated phagocytic killing of several serogroup-heterologous strains in addition to killing all O2/O5 strains. This live, attenuated P. aeruginosa strain PAO1ΔaroA appears to be safe for potential use as an intranasal vaccine and elicits high titers of opsonic antibodies against multiple strains of the P. aeruginosa O2/O5 serogroup.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=127764Documentos Relacionados
- Protection against Fatal Pseudomonas aeruginosa Pneumonia in Mice after Nasal Immunization with a Live, Attenuated aroA Deletion Mutant
- Molecular Characterization of the Aeromonas hydrophila aroA Gene and Potential Use of an Auxotrophic aroA Mutant as a Live Attenuated Vaccine
- Construction and characterization of attenuated delta aroA delta virG Shigella flexneri 2a strain CVD 1203, a prototype live oral vaccine.
- Characterization of a live, attenuated human parainfluenza type 3 virus candidate vaccine strain.
- Characterization of Candidate Live Oral Salmonella typhi Vaccine Strains Harboring Defined Mutations in aroA, aroC, and htrA