The auxotrophic aroA mutant of Aeromonas hydrophila as a live attenuated vaccine against A. salmonicida infections in rainbow trout (Oncorhynchus mykiss)

Fish Shellfish Immunol. 2004 Feb;16(2):193-206. doi: 10.1016/S1050-4648(03)00078-0.


An auxotrophic aroA mutant of the Aeromonas hydrophila AG2 strain is a live attenuated vaccine against A. hydrophila infection in rainbow trout (Oncorhynchus mykiss). The protection conferred by the live attenuated vaccine against A. salmonicida strains is reported here, and several parameters of the specific and non-specific immune response in vaccinated trout were characterised. Vaccination with a dose of 10(7)cells/fish of the aroA mutant elicited significant protection against the Hooke and DK30 strains of A. salmonicida (relative percent survival RPS >60%). This cross-protection correlated moderately with the activation of the humoral and cellular specific immune responses, which show cross-reactivity against antigens shared by the two bacterial species, and a moderate increase in the lysozyme and antiprotease activities in the serum of vaccinated trout.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aeromonas / immunology*
  • Agglutination Tests
  • Analysis of Variance
  • Animals
  • Bacterial Vaccines / immunology*
  • Enzyme-Linked Immunosorbent Assay
  • Fish Diseases / immunology*
  • Fish Diseases / microbiology
  • Gram-Negative Bacterial Infections / prevention & control
  • Gram-Negative Bacterial Infections / veterinary*
  • Leukocytosis / immunology
  • Muramidase / immunology
  • Muramidase / metabolism
  • Oncorhynchus mykiss / microbiology*
  • Protease Inhibitors / immunology
  • Protease Inhibitors / metabolism
  • Vaccines, Attenuated / immunology


  • Bacterial Vaccines
  • Protease Inhibitors
  • Vaccines, Attenuated
  • Muramidase