TY - ABST

T1 - PAMP INDUCED EXPRESSION OF IMMUNE RELEVANT GENES IN HEAD KIDNEY LEUKOCYTES OF RAINBOW TROUT (ONCORHYNCHUS MYKISS)

AU - Chettri, Jiwan Kumar

AU - Holten-Andersen, Lars

AU - Kania, Per Walter

AU - Raida, Martin Kristian

AU - Buchmann, Kurt

PY - 2011/5/3

Y1 - 2011/5/3

N2 - Host immune responses elicited by invading pathogens depend on recognition of the pathogen byspecific receptors present on phagocytic cells. However, the response to viral, bacterial, parasiticand fungal pathogens vary according to the pathogen-associated molecular patterns (PAMPs) on thesurface of the invader. Phagocytic cells are known to initiate a respiratory burst following anexposure to the pathogen, but the underlying and associated specific elements are poorly elucidatedin fish. The present study describes the differential response of head kidney leukocytes fromrainbow trout (Oncorhynchus mykiss) to different PAMPs mimicking bacterial (flagellin and LPS),viral (poly I:C) and fungal infections (zymosan and ß-glucan). Transcript of cytokines related toinflammation (IL-1ß, IL-6, IL-10 and TNF-a) were highly up-regulated following LPS exposurewhereas flagellin or poly I:C induced merely moderate reactions. In contrast, IFN-¿ expression wassignificantly higher in the poly I:C stimulated group compared to LPS group. When head kidneycells were exposed to zymosan or ß-glucan, genes encoding IL-1ß, TNF-a, IL-6 and IL-10 becameup-regulated. Their level of up-regulation was comparable to LPS but the kinetics differed. Inparticular, TNF-a induction was considerably slower when stimulated with zymosan or ß-glucan.The gene encoding COX-2 enzyme, which is a central element in initiation of inflammatoryreactions, was significantly higher in stimulated cells but a depressing effect of high concentrationsof LPS and zymosan became evident after 4 h exposure. This study suggests that rainbow troutleukocytes respond differently to viral, bacterial and fungal PAMPs, which may reflect activation ofspecific signaling cascades eventually leading to activation of different immune effector molecules.

AB - Host immune responses elicited by invading pathogens depend on recognition of the pathogen byspecific receptors present on phagocytic cells. However, the response to viral, bacterial, parasiticand fungal pathogens vary according to the pathogen-associated molecular patterns (PAMPs) on thesurface of the invader. Phagocytic cells are known to initiate a respiratory burst following anexposure to the pathogen, but the underlying and associated specific elements are poorly elucidatedin fish. The present study describes the differential response of head kidney leukocytes fromrainbow trout (Oncorhynchus mykiss) to different PAMPs mimicking bacterial (flagellin and LPS),viral (poly I:C) and fungal infections (zymosan and ß-glucan). Transcript of cytokines related toinflammation (IL-1ß, IL-6, IL-10 and TNF-a) were highly up-regulated following LPS exposurewhereas flagellin or poly I:C induced merely moderate reactions. In contrast, IFN-¿ expression wassignificantly higher in the poly I:C stimulated group compared to LPS group. When head kidneycells were exposed to zymosan or ß-glucan, genes encoding IL-1ß, TNF-a, IL-6 and IL-10 becameup-regulated. Their level of up-regulation was comparable to LPS but the kinetics differed. Inparticular, TNF-a induction was considerably slower when stimulated with zymosan or ß-glucan.The gene encoding COX-2 enzyme, which is a central element in initiation of inflammatoryreactions, was significantly higher in stimulated cells but a depressing effect of high concentrationsof LPS and zymosan became evident after 4 h exposure. This study suggests that rainbow troutleukocytes respond differently to viral, bacterial and fungal PAMPs, which may reflect activation ofspecific signaling cascades eventually leading to activation of different immune effector molecules.

M3 - Conference abstract for conference

T2 - DAFINET, THE ONTOGENY OF THE IMMUNE SYSTEM OF FISH – STATUS AND FUTURE CHALLENGES, Svaneke, Bornholm, Denmark

Y2 - 3 May 2011 through 5 May 2011

ER -