Comparative study of CXC chemokines modulation in brown trout ( Salmo trutta ) following infection with a bacterial or viral pathogen

Abstract

Chemokine modulation in response to pathogens still needs to be fully characterised in fish, in view of the recently described novel chemokines present. This paper reports the first comparative study of CXC chemokine genes transcription in salmonids (brown trout), with a particular focus on the fish specific CXC chemokines (CXCL_F). Adopting new primer sets, optimised to specifically target mRNA, a RT-qPCR gene screening was carried out. Constitutive gene expression was assessed first in six tissues from SPF brown trout. Transcription modulation was next investigated in kidney and spleen during septicaemic infection induced by a RNA virus (Viral Haemorrhagic Septicaemia virus, genotype Ia) or by a Gram negative bacterium (Yersinia ruckeri, ser. O1/biot. 2). From each target organ specific pathogen burden, measured detecting VHSV-glycoprotein or Y. ruckeri 16S rRNA, and IFN-γ gene expression were analysed for their correlation to chemokine transcription. Both pathogens modulated CXC chemokine gene transcript levels, with marked up-regulation seen in some cases, and with both temporal and tissue specific effects apparent. For example, Y. ruckeri strongly induced chemokine transcription in spleen within 24h, whilst VHS generally induced the largest increases at 3d.p.i. in both tissues. This study gives clues to the role of the novel CXC chemokines, in comparison to the other known CXC chemokines in salmonids.

Probiotics Modulate Tilapia Resistance and Immune Response against Tilapia Lake Virus Infection

“…IFN-γ expression was found to be highly induced by both bacterial and viral systemic infections, respectively, caused by Piscine novirhabdovirus and Yersinia ruckeri, in brown trout (Salmo trutta). During these infections, the transcription of IFN-γ was highly correlated to the bacterial and viral load in both spleen and kidney together with a strong correlation to the expression of an array of CXC chemokines, including CXCL8 or IL-8 [52,53]. Moreover, the other antiviral response markers selected for this study in red tilapia, including irf-3, Mx, and VIPERIN (or rsad-2), were previously found to be strongly induced during several viral infections in other teleosts [54][55][56] and involved in the IFN response in tilapia [57].…”

Dietary microalgal-fabricated selenium nanoparticles improve Nile tilapia biochemical indices, immune-related gene expression, and intestinal immunity

“…Total RNA was manually extracted from 100 mg of each intestinal sample from each group (control, SeNPs0.75, SeNPs1.5) using a handheld homogenizer to homogenize the tissue immersed in one mL Genzol™ (Geneaid Biotech Ltd., Taiwan) without DNase treatment. The pellet was dissolved in TE buffer (pH 8.0) as described previously [ 40 ]. The RNA quantity was estimated using a NanoDrop spectrophotometer (Q5000/Quawell, Massachusetts, USA).…”

Dietary algal-sourced zinc nanoparticles promote growth performance, intestinal integrity, and immune response of Nile tilapia (Oreochromis niloticus)

“…Total RNA was manually extracted from 100 mg of the anterior kidney using a handheld homogenizer to disperse the tissue immersed in one mL of Genzol TM (Geneaid Biotech Ltd, Taiwan) without DNase treatment. The pellet was dissolved in TE buffer (pH 8.0) as described previously [ 40 ]. The RNA quantity was estimated using a Nanodrop spectrophotometer (Q5000/Quawell, Massachusetts, USA).…”