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nicity of LPS, but also emphasised that rainbow trout responded to exopolysaccharide. LPS from Aer. hydrophila administered as three doses by immersion (150 μg/
ml); RPS = 49 % for 90 min on 3 days or i.p. injection (3 doses each of 50 and 100 μg/
fi sh; RPS = 100 %) but not orally into carp led to high levels of protection following
challenge with Aer. hydrophila (Selvaraj et al. 2009 ). LPS from a virulent and non
virulent strain of Aer. hydrophila were injected intraperitoneally in 50 and 75 μg/100 g
of body weight amounts into carp ( Cyprinus carpio ) leading – especially in the case
of the LPS from the non virulent stain – to immunostimulation, i.e. increased leukocyte count, lysozyme and phagocytic activity, and the production of ROS, and protection against challenge (Grochola et al. 2015 ). LPS and OMP vaccines (derived
from a culture of Aer. hydrophila ) were effective at immunostimulation (enhanced
respiratory burst, phagocytic and serum lysozyme activities) and protection against
disease (RPS = 83.3 % and 72.2 % for LPS and OMP, respectively, compared with
55.6 % for a formalin-inactivated whole cell preparation) when administered to grass
carp (Ctenopharyngodon idella), which were challenged with Aer. hydrophila (Sun
et al. 2012 ). The adhesion gene from Aer. hydrophila , which belonged to the maltoporin group of porins coding for OMP, Omp48, was cloned and sequenced. The
recombinant protein of ~ 48 kDa molecular weight was administered to rohu and
upon challenge with Aer. hydrophila resulted in protection (RPS = 69 %)
(Khushiramani et al. 2012 ). A recombinant S-layer protein was immunoprotective
(RPS = 56–87 %) when administered in an adjuvant by i.p. injection (30 μg protein/
fi sh) in common carp (Poobalane et al. 2010 ). A live aroA vaccine has been evaluated in rainbow trout with success. Interestingly, the growth medium was shown to
have marked effect on immunogenicity, in that cultures prepared in glucose containing media, i.e. brain heart infusion (BHI), Luria broth with 0.25 % (w/v) glucose and
TSB, led to a reduction in complement consumption and reduced serum susceptibility compared with BHI and Luria broth grown cells which were suspended in
PBS. Indeed, these preparations led to higher and longer-lasting serum antibody
titres than cells cultured in TSB (Vivas et al. 2005 ). Another live genetically modifi ed
auxotrophic mutant of Aer. hydrophila has been evaluated, and environmental concerns addressed in work which determined that the cells disappeared within 15 days,
but may well enter a NCBV state (Vivas et al. 2004 ). Two OMPs, Aha1 and OmpW,
were overexpressed in Esch. coli, purifi ed, and administered to common carp when
after challenge RPSs of 52 % and 71 %, respectively, were recorded (Maiti et al.
2012 ). An interesting study revealed the protective effect of a recombinant protein
vaccine, aerA, could be enhanced by using single walled carbon nanotubes as a
delivery vehicle for immersion or i.m. injection uptake in terms of increased antibody titre and protection against challenge (RPS = ~80 %) (Gong et al. 2015 ).
A freeze (3 min in liquid nitrogen) thaw (followed by 3 min at 37 °C) lysate was
evaluated in FCA by i.p. administration (20 μg of lysate/fi sh in an equi-volume of
FCA) in rainbow trout with a low dose challenge after 4-weeks when the RPS value
was reported as 97 % (LaPatra et al. 2010 ).
Zhao et al. ( 2011 ) used the glyceraldehyde-3-phosphate dehydrogenase
(GAPDH) gene gapA to express Aer. hydrophila GAPDH in an attenuated V. anguillarum strain, which was injected i.p. (10
6 CFU/fi sh) into turbot and challenged after
4-weeks. Challenge of cytoplasm GAPDH expressing strain AV/pUC-gapA4 Aeromonadaceae Representatives (Motile Aeromonads)
nicity of LPS, but also emphasised that rainbow trout responded to exopolysaccharide. LPS from Aer. hydrophila administered as three doses by immersion (150 μg/
ml); RPS = 49 % for 90 min on 3 days or i.p. injection (3 doses each of 50 and 100 μg/
fi sh; RPS = 100 %) but not orally into carp led to high levels of protection following
challenge with Aer. hydrophila (Selvaraj et al. 2009 ). LPS from a virulent and non
virulent strain of Aer. hydrophila were injected intraperitoneally in 50 and 75 μg/100 g
of body weight amounts into carp ( Cyprinus carpio ) leading – especially in the case
of the LPS from the non virulent stain – to immunostimulation, i.e. increased leukocyte count, lysozyme and phagocytic activity, and the production of ROS, and protection against challenge (Grochola et al. 2015 ). LPS and OMP vaccines (derived
from a culture of Aer. hydrophila ) were effective at immunostimulation (enhanced
respiratory burst, phagocytic and serum lysozyme activities) and protection against
disease (RPS = 83.3 % and 72.2 % for LPS and OMP, respectively, compared with
55.6 % for a formalin-inactivated whole cell preparation) when administered to grass
carp (Ctenopharyngodon idella), which were challenged with Aer. hydrophila (Sun
et al. 2012 ). The adhesion gene from Aer. hydrophila , which belonged to the maltoporin group of porins coding for OMP, Omp48, was cloned and sequenced. The
recombinant protein of ~ 48 kDa molecular weight was administered to rohu and
upon challenge with Aer. hydrophila resulted in protection (RPS = 69 %)
(Khushiramani et al. 2012 ). A recombinant S-layer protein was immunoprotective
(RPS = 56–87 %) when administered in an adjuvant by i.p. injection (30 μg protein/
fi sh) in common carp (Poobalane et al. 2010 ). A live aroA vaccine has been evaluated in rainbow trout with success. Interestingly, the growth medium was shown to
have marked effect on immunogenicity, in that cultures prepared in glucose containing media, i.e. brain heart infusion (BHI), Luria broth with 0.25 % (w/v) glucose and
TSB, led to a reduction in complement consumption and reduced serum susceptibility compared with BHI and Luria broth grown cells which were suspended in
PBS. Indeed, these preparations led to higher and longer-lasting serum antibody
titres than cells cultured in TSB (Vivas et al. 2005 ). Another live genetically modifi ed
auxotrophic mutant of Aer. hydrophila has been evaluated, and environmental concerns addressed in work which determined that the cells disappeared within 15 days,
but may well enter a NCBV state (Vivas et al. 2004 ). Two OMPs, Aha1 and OmpW,
were overexpressed in Esch. coli, purifi ed, and administered to common carp when
after challenge RPSs of 52 % and 71 %, respectively, were recorded (Maiti et al.
2012 ). An interesting study revealed the protective effect of a recombinant protein
vaccine, aerA, could be enhanced by using single walled carbon nanotubes as a
delivery vehicle for immersion or i.m. injection uptake in terms of increased antibody titre and protection against challenge (RPS = ~80 %) (Gong et al. 2015 ).
A freeze (3 min in liquid nitrogen) thaw (followed by 3 min at 37 °C) lysate was
evaluated in FCA by i.p. administration (20 μg of lysate/fi sh in an equi-volume of
FCA) in rainbow trout with a low dose challenge after 4-weeks when the RPS value
was reported as 97 % (LaPatra et al. 2010 ).
Zhao et al. ( 2011 ) used the glyceraldehyde-3-phosphate dehydrogenase
(GAPDH) gene gapA to express Aer. hydrophila GAPDH in an attenuated V. anguillarum strain, which was injected i.p. (10
6 CFU/fi sh) into turbot and challenged after
4-weeks. Challenge of cytoplasm GAPDH expressing strain AV/pUC-gapA4 Aeromonadaceae Representatives (Motile Aeromonads)