1 research outputs found
Establishment of Infection Models in Zebrafish Larvae (Danio rerio) to Study the Pathogenesis of Aeromonas hydrophila
This is an open-access article distributed under the terms of the Creative Commons Attribution License
(CCBY)Aeromonas hydrophila is a Gram-negative opportunistic pathogen of fish and terrestrial
animals. In humans, A. hydrophila mainly causes gastroenteritis, septicaemia, and tissue
infections. The mechanisms of infection, the main virulence factors and the host immune
response triggered by A. hydrophila have been studied in detail using murine models and
adult fish. However, the great limitation of studying adult animals is that the animal must
be sacrificed and its tissues/organs extracted, which prevents the study of the infectious
processes in the whole living animal. Zebrafish larvae are being used for the analysis of
several infectious diseases, but their use for studying the pathogenesis of A. hydrophila
has never been explored. The great advantage of zebrafish larvae is their transparency
during the first week after fertilization, which allows detailed descriptions of the infectious
processes using in vivo imaging techniques such as differential interferential contrast
(DIC) and fluorescence microscopy. Moreover, the availability of fluorescent pathogens
and transgenic reporter zebrafish lines expressing fluorescent immune cells, immune
marker genes or cytokines/chemokines allows the host–pathogen interactions to be
characterized. The present study explores the suitability of zebrafish larvae to study the
pathogenesis of A. hydrophila and the interaction mechanisms between the bacterium
and the innate immune responses through an infection model using different routes
for infection. We used an early-embryo infection model at 3 days post-fertilization
(dpf) through the microinjection of A. hydrophila into the duct of Cuvier, caudal vein,
notochord, or muscle and two bath infection models using 4 dpf healthy and injured
larvae. The latter resembled the natural conditions under which A. hydrophila produces
infectious diseases in animals. We compared the cellular processes after infection in
each anatomical site by confocal fluorescence imaging and determined the implication
of inflammatory immune genes by measuring gene expression by qPCR14 páginas, 5 figuras.-- This work was supported by the European Union Seventh Framework Programme (FP7PEOPLE-2011-ITN) under the Marie-Curie Initial Training Network FishForPharma (PITN-GA-2011-289209) and by Project AGL2014-51773-C3 and Project 201230E057 (CSIC) from the Spanish Ministerio de EconomÃa y Competitividad.Peer reviewe