Pathophysiology of experimental Aeromonas hydrophila infection in Puntius sarana: Early changes in blood and aspects of the innate immune-related gene expression in survivors

Modulation of the innate immune responses in the striped snakehead murrel, <i>Channa striata</i> upon experimental infection with live and heat killed <i>Aeromonas hydrophila</i>

“…In the present study, the serum peroxidase level was significantly (P<0·05) enhanced in the group challenged with live or killed A. hydrophila till day 5 and 10 respectively after challenge. In another study, a significant increase in serum myeloperoxidase was observed as an early infection period response in P. sarana following an intraperitoneal challenge with A. hydrophila (Das et al, 2011). Similarly, serum PO levels increased in gilt-head seabream (Sparus aurata) exposed to Enteromyxum leei or heat inactivated probiotic bacteria (Diaz-Rosales et al, 2006).…”

“…In greater amberjack, Seriola dumerili an increase in lysozyme was detected on an experimental challenge with the bacterial pathogen Listonella (Vibrio) anguillarum (Caruso et al, 2011). The lysozyme producing immune related genes such as lysozyme G, lysozyme C genes were found to be significantly up-regulated (induced) in the kidney of Puntius sarana (Olive Barb) following an intraperitoneal challenge with A. hydrophila (Das et al, 2011). The inducible nature of lysozyme activity reported earlier is again confirmed in the present investigation where the serum lysozyme response was found to be induced to a significantly (P<0·05) higher level in the group challenged with the live virulent or heat killed A. hydrophila.…”

Post-challenge immune gene expression profiling in rohu, Labeo rohita vaccinated with modified adjuvant-basedohu, Aeromonas hydrophila outer membrane protein R formulationˆ:l3

“…Antibody-mediated humoral immunity plays a major role in fish during bacterial infections, such as Vibrio anguillarum, A. hydrophila, Flavobacterium psychrophilum, Streptococcus agalactiae and Streptococcus iniae, and results in increased protection (JIAO et al, 2010). Many researchers have looked at the changes in gene expression in fish, post-vaccination or post-infection, but our knowledge of the post-challenge immune response in vaccinated fish is very limited (HARUN et al, 2011;DAS et al, 2011;MAHAPATRA et al, 2008).…”

“…An elevated IgM titer was marked in A. hydrophila resistant common carp families, when challenged with the specific pathogen (ARDO et al, 2010). C3 is considered to be an important antimicrobial weapon of teleosts, which initiates complement mediated opsonization during infection (DAS et al, 2011). Increased C3 levels at an early hour after challenge, as well as at subsequent time points (24, 72 and 120 hpc) in group F fish, perhaps suggest the immediate activation of the complement cascade in animals injected with this modified adjuvant-rOmpR, which leads to the early clearance of the pathogen by activated phagocytosis/opsonization like activities.…”

“…Expression analysis of immune genes in naïve fish during infection or in vaccinated fish following challenge has always been of interest in the field of infection and immunity. Pro-inflammatory cytokines were found to be induced in the anterior kidney of Puntius sarana during initial periods of infection with A. hydrophila (DAS et al, 2011). An increase in the expression of TNF-α and IL-8 has been reported in Zebrafish, vaccinated with a mutated strain of E. tarda (WED: a live attenuated strain of E. tarda) at early periods postchallenge.…”