Limits...
Individual Monitoring of Immune Response in Atlantic Salmon Salmo salar following Experimental Infection with Infectious Salmon Anaemia Virus (ISAV).

Collet B, Urquhart K, Monte M, Collins C, Garcia Perez S, Secombes CJ, Hall M - PLoS ONE (2015)

Bottom Line: This approach contributes to the reduction of animals used in research and to improved data quality.A strong increase in viraemia as well as a significant induction of Mx and γIP gene expression were observed in the infected group.These results and the advantages of this approach are discussed.

View Article: PubMed Central - PubMed

Affiliation: Aquaculture and Fish Health, Marine Scotland, Aberdeen, Scotland, United Kingdom.

ABSTRACT
Monitoring the immune response in fish over the progression of a disease is traditionally carried out by experimental infection whereby animals are killed at regular intervals and samples taken. We describe here a novel approach to infectiology for salmonid fish where blood samples are collected repeatedly in a small group of PIT-tagged animals. This approach contributes to the reduction of animals used in research and to improved data quality. Two groups of 12 PIT-tagged Atlantic salmon (Salmo salar) were i.p infected with Infectious Salmon Anaemia Virus (ISAV) or culture medium and placed in 1 m3 tanks. Blood samples were collected at 0, 4, 8, 12, 16, 21 and 25 days post infection. The viral load, immune and stress response were determined in individual fish by real-time quantitative PCR (QPCR) on the blood cells, as well as the haematocrit used as an indicator of haemolysis, a clinical consequence of ISAV infection. "In-tank" anaesthesia was used in order to reduce the stress related to chase and netting prior to sampling. The data were analysed using a statistical approach which is novel with respect to its use in fish immunology. The repeated blood collection procedure did not induce stress response as measured by HSP70 and HSP90 gene expression in the un-infected animals. A strong increase in viraemia as well as a significant induction of Mx and γIP gene expression were observed in the infected group. Interleukin 10 was found induced at the later stage of the infection whereas no induction of CD8 or γ IFN could be detected. These results and the advantages of this approach are discussed.

No MeSH data available.


Related in: MedlinePlus

Log10 ISAV load for challenged experimental group individuals over the course of the experiment.The solid line (—) is included as an aid to follow the response of the individual with the highest value. Values around the fixed time points of 4, 8, 12, 16, 21 & 25 days have been horizontally jittered to improve visualisation.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4580571&req=5

pone.0137767.g002: Log10 ISAV load for challenged experimental group individuals over the course of the experiment.The solid line (—) is included as an aid to follow the response of the individual with the highest value. Values around the fixed time points of 4, 8, 12, 16, 21 & 25 days have been horizontally jittered to improve visualisation.

Mentions: Mean viraemia of the infected challenge-group based on QPCR and expressed as relative units, was 1x10–3 ± 1x10–4 at the first post-challenge sampling point (dpi 4) and 60 ± 30 at the termination of the experiment (dpi 25). A plot of post-challenge log response ratios shows an increase in viraemia over time with a plateau occurring towards the end of the experiment (Fig 2).


Individual Monitoring of Immune Response in Atlantic Salmon Salmo salar following Experimental Infection with Infectious Salmon Anaemia Virus (ISAV).

Collet B, Urquhart K, Monte M, Collins C, Garcia Perez S, Secombes CJ, Hall M - PLoS ONE (2015)

Log10 ISAV load for challenged experimental group individuals over the course of the experiment.The solid line (—) is included as an aid to follow the response of the individual with the highest value. Values around the fixed time points of 4, 8, 12, 16, 21 & 25 days have been horizontally jittered to improve visualisation.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4580571&req=5

pone.0137767.g002: Log10 ISAV load for challenged experimental group individuals over the course of the experiment.The solid line (—) is included as an aid to follow the response of the individual with the highest value. Values around the fixed time points of 4, 8, 12, 16, 21 & 25 days have been horizontally jittered to improve visualisation.
Mentions: Mean viraemia of the infected challenge-group based on QPCR and expressed as relative units, was 1x10–3 ± 1x10–4 at the first post-challenge sampling point (dpi 4) and 60 ± 30 at the termination of the experiment (dpi 25). A plot of post-challenge log response ratios shows an increase in viraemia over time with a plateau occurring towards the end of the experiment (Fig 2).

Bottom Line: This approach contributes to the reduction of animals used in research and to improved data quality.A strong increase in viraemia as well as a significant induction of Mx and γIP gene expression were observed in the infected group.These results and the advantages of this approach are discussed.

View Article: PubMed Central - PubMed

Affiliation: Aquaculture and Fish Health, Marine Scotland, Aberdeen, Scotland, United Kingdom.

ABSTRACT
Monitoring the immune response in fish over the progression of a disease is traditionally carried out by experimental infection whereby animals are killed at regular intervals and samples taken. We describe here a novel approach to infectiology for salmonid fish where blood samples are collected repeatedly in a small group of PIT-tagged animals. This approach contributes to the reduction of animals used in research and to improved data quality. Two groups of 12 PIT-tagged Atlantic salmon (Salmo salar) were i.p infected with Infectious Salmon Anaemia Virus (ISAV) or culture medium and placed in 1 m3 tanks. Blood samples were collected at 0, 4, 8, 12, 16, 21 and 25 days post infection. The viral load, immune and stress response were determined in individual fish by real-time quantitative PCR (QPCR) on the blood cells, as well as the haematocrit used as an indicator of haemolysis, a clinical consequence of ISAV infection. "In-tank" anaesthesia was used in order to reduce the stress related to chase and netting prior to sampling. The data were analysed using a statistical approach which is novel with respect to its use in fish immunology. The repeated blood collection procedure did not induce stress response as measured by HSP70 and HSP90 gene expression in the un-infected animals. A strong increase in viraemia as well as a significant induction of Mx and γIP gene expression were observed in the infected group. Interleukin 10 was found induced at the later stage of the infection whereas no induction of CD8 or γ IFN could be detected. These results and the advantages of this approach are discussed.

No MeSH data available.


Related in: MedlinePlus