Atlantic salmon kidney (ASK) cells are an effective model to characterise interferon (IFN) and IFN-induced gene expression following salmonid alphavirus infection

Abstract Background Vertebrate hosts limit the availability of iron to microbial pathogens in order to nutritionally starve the invaders. The impact of iron deficiency induced by the iron chelator deferoxamine mesylate (DFO) was investigated in Atlantic salmon SHK-1 cells infected with the facultative intracellular bacterium Piscirickettsia salmonis. Results Effects of the DFO treatment and P. salmonis on SHK-1 cells were gaged by assessing cytopathic effects, bacterial load and activity, and gene expression profiles of eight immune biomarkers at 4- and 7-days post infection (dpi) in the control group, groups receiving single treatments (DFO or P. salmonis) and their combination. The chelator appears to be well-tolerated by host cells, while it had a negative impact on the number of bacterial cells and associated cytotoxicity. DFO alone had minor effects on gene expression of SHK-1 cells, including an early activation of IL-1β at 4 dpi. In contrast to few moderate changes induced by single treatments (either infection or chelator), most genes had highest upregulation in the infected groups receiving DFO. The mildest induction of hepcidin-1 (antimicrobial peptide precursor and regulator of iron homeostasis) was observed in cells exposed to DFO alone, followed by P. salmonis infected cells while the addition of DFO to infected cells further increased the mRNA abundance of this gene. Transcripts encoding TNF-α (immune signaling) and iNOS (immune effector) showed sustained increase at both time points in this group while cathelicidin-1 (immune effector) and IL-8 (immune signaling) were upregulated at 7 dpi. The stimulation of protective gene responses seen in infected cultures supplemented with DFO coincided with the reduction of bacterial load and activity (judged by the expression of P. salmonis 16S rRNA), and damage to cultured host cells. Conclusion The absence of immune gene activation under normal iron conditions suggests modulation of host responses by P. salmonis. The negative effect of iron deficiency on bacteria likely allowed host cells to respond in a more protective manner to the infection, further decreasing its progression. Presented findings encourage in vivo exploration of iron chelators as a promising strategy against piscirickettsiosis.

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Enzyme characterisation and gene expression profiling of Atlantic salmon chicken- and goose-type lysozymes

Developmental & Comparative Immunology ◽

10.1016/j.dci.2013.01.010 ◽

2013 ◽

Vol 40 (1) ◽

pp. 11-19 ◽

Cited By ~ 23

Author(s):

Bjørnar Myrnes ◽

Marit Seppola ◽

Audny Johansen ◽

Kersti Øverbø ◽

Lien Callewaert ◽

...

Keyword(s):

Gene Expression ◽

Atlantic Salmon ◽

Gene Expression Profiling ◽

Expression Profiling ◽

Enzyme Characterisation

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Gene expression analyses in Atlantic salmon challenged with infectious salmon anemia virus reveal differences between individuals with early, intermediate and late mortality

BMC Genomics ◽

10.1186/1471-2164-9-179 ◽

2008 ◽

Vol 9 (1) ◽

pp. 179 ◽

Cited By ~ 90

Author(s):

Sven Jørgensen ◽

Sergey Afanasyev ◽

Aleksei Krasnov

Keyword(s):

Gene Expression ◽

Atlantic Salmon ◽

Infectious Salmon Anemia Virus ◽

Late Mortality ◽

Infectious Salmon Anemia ◽

Gene Expression Analyses ◽

Salmon Anemia Virus ◽

Anemia Virus

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A single nuclei transcriptomic analysis of the Atlantic salmon gill through smoltification and seawater transfer

10.1101/2020.09.03.281337 ◽

2020 ◽

Author(s):

Alexander C. West ◽

Yasutaka Mizoro ◽

Shona H. Wood ◽

Louise M. Ince ◽

Marianne Iversen ◽

...

Keyword(s):

Gene Expression ◽

Atlantic Salmon ◽

Direct Evidence ◽

Cell Types ◽

Prior Work ◽

In The Wild ◽

Induced Changes ◽

Freshwater Environments ◽

Transcriptomic Studies

AbstractAnadromous salmonids begin life adapted to the freshwater environments of their natal streams before a developmental transition, known as smoltification, transforms them into marine-adapted fish. In the wild, the extending photoperiods of spring stimulates smoltification, typified by radical reprogramming of the gill from an ion-absorbing organ to ion-excreting organ. Prior work has highlighted the role of specialized “mitochondrion-rich” cells in delivering this phenotype. However, transcriptomic studies identify thousands of smoltification-driven differentially regulated genes, indicating that smoltification causes a multifaceted, multicellular change; but direct evidence of this is lacking.Here, we use single-nuclei RNAseq to characterize the Atlantic salmon gill during smoltification and seawater transfer. We identify 20 distinct clusters of nuclei, including known, but also novel gill cell types. These data allow us to isolate cluster-specific, smoltification-induced changes in gene expression. We also show how cellular make-up of the gill changes through smoltification. As expected, we noted an increase in the proportion of seawater mitochondrion-rich cells, however, we also identify a reduction of several immune-related cells. Overall, our results provide unrivaled detail of the cellular complexity in the gill and suggest that smoltification triggers unexpected immune reprogramming directly preceding seawater entry.

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