PUBLICATION
Francisella noatunensis subspecies noatunensis clpB deletion mutant impairs development of francisellosis in a zebrafish model
- Authors
- Lampe, E.O., Zingmark, C., Tandberg, J.I., Thrane, I.M.P., Brudal, E., Sjöstedt, A., Winther-Larsen, H.C.
- ID
- ZDB-PUB-171121-4
- Date
- 2017
- Source
- Vaccine 35(52): 7264-7272 (Journal)
- Registered Authors
- Keywords
- Atlantic cod, ClpB, Francisella noatunensis, Francisellosis, Immunization, Zebrafish
- MeSH Terms
-
- Animals
- Antibody Formation
- Aquaculture
- Bacterial Proteins/genetics
- Disease Models, Animal
- Fish Diseases/immunology
- Fish Diseases/microbiology
- Fish Diseases/mortality
- Fish Diseases/prevention & control*
- Francisella/genetics*
- Francisella/immunology
- Gadus morhua/immunology
- Gadus morhua/microbiology
- Gram-Negative Bacterial Infections/immunology
- Gram-Negative Bacterial Infections/microbiology
- Gram-Negative Bacterial Infections/prevention & control
- Gram-Negative Bacterial Infections/veterinary*
- Immunogenicity, Vaccine
- Interleukin-1beta/genetics
- Interleukin-8/biosynthesis
- Interleukin-8/immunology
- Sequence Deletion
- Vaccination
- Vaccines, Attenuated/administration & dosage
- Vaccines, Attenuated/immunology
- Zebrafish/immunology
- Zebrafish/microbiology*
- PubMed
- 29153776 Full text @ Vaccine
Citation
Lampe, E.O., Zingmark, C., Tandberg, J.I., Thrane, I.M.P., Brudal, E., Sjöstedt, A., Winther-Larsen, H.C. (2017) Francisella noatunensis subspecies noatunensis clpB deletion mutant impairs development of francisellosis in a zebrafish model. Vaccine. 35(52):7264-7272.
Abstract
Background Francisella noatunensis ssp. noatunensis (F.n.n.) is the causative agent of francisellosis in Atlantic cod and constitutes one of the main challenges for future aquaculture on this species. A facultative intracellular bacterium like F.n.n. exert an immunologic challenge against which live attenuated vaccines in general are most effective. Thus, we constructed a deletion in the F.n.n. clpB gene as ΔclpB mutants are among the most promising vaccine candidates in human pathogenic Francisella.
Purpose Characterization of F.n.n. ΔclpB using primary Atlantic cod head kidney leukocytes, the zebrafish embryo and adult zebrafish model with focus on potential attenuation, relevant immune responses and immunogenic potential.
Main results Interleukin 1 beta transcription in Atlantic cod leukocytes was significantly elevated from 24 to 96 h post infection with F.n.n. ΔclpB compared to F.n.n. wild-type (wt). Growth attenuation of the deletion mutant in zebrafish embryos was observed by fluorescence microscopy and confirmed by genome quantification by qPCR. In the immunization experiment, adult zebrafish were immunized with 7 × 106 CFU of F.n.n. ΔclpB before challenge four weeks later with 6 × 108 CFU of F.n.n. wt. One day after challenge, immunized zebrafish responded with significantly lower interleukin 8 levels compared to the non-immunized control. Immunized fish were protected against the acute mortality observed in non-immunized zebrafish after challenge and bacterial genomes quantified by qPCR were reduced to a minimum 28 days post challenge, indicating protective immunity stimulated by F.n.n. ΔclpB.
Conclusion Deletion mutation of clpB in F.n.n. causes in vitro and in vivo attenuation and elicits a protective immune response in adult zebrafish against a lethal dose of F.n.n. wt. Taken together, the results presented increases the knowledge on protective immune responses against F.n.n.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping