VHSV IVb infection and autophagy modulation in the rainbow trout gill epithelial cell line RTgill‐W1

Abstract

Viral haemorrhagic septicaemia virus (VHSV) is a negative-stranded RNA virus and a member of the Rhabdoviridae family that can cause severe disease in fish (Lumsden, 2017; Skall, Olesen, & Mellergaard, 2005). Subgenotype IVb was identified from a mortality event in freshwater drum (Aplodinotus grunniens) in Lake Ontario (Lumsden et al., 2007). Experimentally, this virus causes high mortality in numerous species of fish including fathead minnow (Pimphales

Impact of feed restriction, chloroquine and deoxynivalenol on viral haemorrhagic septicaemia virus IVb in fathead minnow Pimephales promelas Rafinesque

“…The pathogenicity and replication of some intracellular pathogens, especially virus, are impacted by autophagy (O'Donnell et al., 2011; Sun et al., 2014). Modulation of autophagy, therefore, offers the potential to impact the outcome of viral infection in different animals including fish (Garcia‐Valtanen et al., 2014; Liu et al., 2015, 2020). Most studies to date, however, have been performed in vitro.…”

“…Restricted nutrition, chloroquine (CQ) and deoxynivalenol (DON), which is a trichothecene mycotoxin (Pestka, 2010), have been shown to modulate autophagy activity in different animal models (Han et al., 2016; Sun et al., 2014; Yabu et al., 2012), including rainbow trout Oncorhynchus mykiss Walbaum (Liu et al., 2020). Inhibition (DON) or blockage of autophagy (CQ) significantly reduced viral haemorrhagic septicaemia virus IVb (VHSV) in a rainbow trout gill epithelial cell line (Liu et al., 2020). Restricted nutrition and feed containing DON, respectively, significantly decreased the sensitivity of rainbow trout to experimental infection with Flavobacterium psychrophilum (Ryerse et al., 2015), while feed containing CQ also showed some potential (Liu, 2019).…”

“…After infection, fish were again fed their assigned diets twice daily. The virus was originally from a mortality event in freshwater drum Aplodinotus grunniens Rafinesque from Lake Ontario, Canada (Lumsden et al., 2007), and was propagated in the epithelioma papulosum cyprini cell line as described (Liu et al., 2020).…”

“…CQ‐fed rainbow trout also had reduced mortality compared to fully fed fish after infection with F. psychrophilium (Liu, 2019). CQ (50 µM) had the greatest effect, followed by DON (1 µM), to inhibit VHSV IVb replication in a rainbow trout gill cell line (RTgill‐W1) in vitro (Liu et al., 2020), and CQ also inhibited viral replication in other in vitro models (Sun et al., 2014; Zhu et al., 2012). The potential of CQ (hydroxychloroquine) has also received considerable attention for treating the pandemic pneumonia caused by SARS‐CoV‐2 (Colson et al., 2020).…”

Autophagy modulation in rainbow trout Oncorhynchus mykiss L. and resistance to experimental infection with Flavobacterium psychrophilum

“…The majority of research on autophagy has taken place in humans, laboratory animals and livestock. Autophagy research in fish is relatively sparse and has focused on a few fish species including zebrafish and rainbow trout (Liu, Balmori‐Cedeno, et al., 2020; Liu, Pham, et al., 2020; Seiliez et al., 2010; Varga et al., 2015; Xia et al., 2019). The research to date has been limited to the influence of autophagy on fish rhabdovirus infection in cell lines.…”