New cell lines for efficient propagation of koi herpesvirus and infectious salmon anaemia virus

Abstract

The production of piscine viruses, in particular of koi herpesvirus (KHV, CyHV‐3) and infectious salmon anaemia virus (ISAV), is still challenging due to the limited susceptibility of available cell lines to these viruses. A number of cell lines from different fish species were compared to standard diagnostic cell lines for KHV and ISAV regarding their capability to exhibit a cytopathic effect (CPE) and to accumulate virus. Two cell lines, so far undescribed, appeared to be useful for diagnostic purposes. Fr994, a cell line derived from ovaries of rainbow trout (Oncorhynchus mykiss), produced constantly high ISA virus (ISAV) titres and developed a pronounced CPE even at high cell passage numbers, while standard cell lines are reported to gradually loose these properties upon propagation. Another cell line isolated from the head kidney of common carp (Cyprinus carpio), KoK, showed a KHV induced CPE earlier than the standard cell line used for diagnostics. A third cell line, named Fin‐4, established from the fin epithelium of rainbow trout did not promote efficient replication of tested viruses, but showed antigen sampling properties and might be useful as an in vitro model for virus uptake or phagocytosis.

Comprehensive update on inventory of finfish cell lines developed during the last decade (2010–2020)

“…However, rainbow trout, Oncorhynchus mykiss was the most widely used finfish for cell culture development followed by the siberian sturgeon (Acipenser baerii), goldfish (Carassius auratus), half-smooth tongue sole (Cynoglossus semilaevis), zebrafish (Danio rerio) and the snakehead (Channa striata). In addition to previously existing cell lines, 25 new cell lines including eight ovarian (Verrier et al 2012;Vo et al 2015b;Eckart et al, 2018), five pituitary gland , three milt (Vo et al 2015b), two each of intestine (Kawano et al 2011;Drieschner et al 2019) and head kidney (Fierro-Castro et al 2012;Maisey et al 2016) and one each of heart (Luque et al 2014), spleen (Fierro-Castro et al 2012), and ovarian fluid, fin and gill (Yue, 2015) cell lines were developed from rainbow trout. Cell lines were developed in India from the green chromide (Etroplus suratensis; Babu et al 2012) Swaminathan et al 2015), angelfish (Pterophyllum scalare; Swaminathan et al 2016a), Oscar (Astronotus ocellatus; Kumar et al 2019) and goldfish (C. auratus; Dharmaratnam et al 2020) were also developed.…”

“…2012; Vo et al . 2015b; Eckart et al ., 2018), five pituitary gland (Chen et al . 2010), three milt (Vo et al .…”

Susceptibility of Pimephales promelas and Carassius auratus to a strain of koi herpesvirus isolated from wild Cyprinus carpio in North America

“…Isolation of CyHV-3 on permissive cell lines is a definitive method for determining the presence of infectious CyHV-3 in tissue and environmental samples but permissible cell lines, Koi fin (KF-1) and common carp brain (CCB), are not highly susceptible to CyHV-3 [21][22][23] and are not considered a sensitive diagnostic tool 10 . Recently, cell lines with higher sensitivity to CyHV-3 have been reported 24 but are not yet widely available.…”

Development of a real-time duplex PCR assay for simultaneously diagnosis of KHV and CEV in common carp and koi

“…Co-infection between KHV and CEV has been reported during mortality events of culture and wild common carp in USA and Iraq (Padhi et al, 2019;Toffan et al, 2019). Multiple diagnostic methods such as, inoculation virus in cell cultures, histological examination, and electron microscopy are required to detect and differentiate these two viral pathogens (Eckart et al, 2019;Miwa et al, 2015;Miyazaki et al, 2005;Miyazaki et al, 2008;Ouyang et al, 2018;Wang et al, 2013). However, these methods are time-consuming and laborintensive.…”