Characterization and viral susceptibility of a brain cell line from brown‐marbled grouper Epinephelus fuscoguttatus (Forsskål) with persistent betanodavirus infection

Abstract

A continuous cell line designated BMGB (brown-marbled grouper brain) was established from the brain tissues of the brown-marbled grouper Epinephelus fuscoguttatus and characterized. BMGB cells were identified as astroglial progenitor cells because they expressed glial fibrillary acidic protein and keratin and were persistently infected by betanodavirus, as confirmed through immunocytochemistry, polymerase chain reaction and immunoblot analyses. Because few intact virions were present in the BMGB cell culture fluid, the cytopathic effect (CPE) was not observed when the culture fluid was inoculated with GBC1 cells. However, BMGB cells displayed typical CPE after infection with additional betanodavirus, megalocytivirus and chum salmon reovirus. BMGB cells showed low myxovirus resistance (Mx) protein expression, which increased following betanodavirus and reovirus infection. Because the cells contained several unusual or degraded viral proteins, the persistent infection of betanodavirus in the BMGB cells may have resulted from a mechanism that destroys the viral proteins rather than the result of Mx protein expression. Despite the persistent betanodavirus infection, BMGB cells proliferated in a manner similar to other normal tropic fish cells and supported the propagation of several piscine viruses; however, the yield was lower than that of normal cells. The BMGB cells will be useful for investigating virus and host cell interaction.

Development, characterization and virus susceptibility of a continuous cell line from the caudal fin of marbled eel (Anguilla marmorata)

“…Nevertheless, the cell‐aggregation CPE has also been observed in snakehead reovirus and American grass carp reovirus‐infected cells (Goodwin, Merry, & Attoui, ; John, George, Richards, & Frerichs, ), and the virus yields were not significantly lower than those of syncytial reoviruses. In this study, CVS infection resulted in non‐syncytial clear plaques in MECF‐1 monolayers, with virus production as high as those of the cell lines that exhibited syncytia (Wen, ; Wen et al., ). The factors that caused CPE variation remain unclarified.…”

“…Anguillid cell lines such as EK-1 (Chen & Kou, 1982) and EO-2 (Chen & Kou, 1981) & Miyazaki, 2001;Lee, Nomura, & Miyazaki, 1999;Van Beurden, Gatherer, et al, 2012;Wen, Liu, & Nan, 2017;Wen et al, 2016). However, they have limited applications because they are | 1335 monolayers, with virus production as high as those of the cell lines that exhibited syncytia (Wen, 2016;Wen et al, 2013). The factors that caused CPE variation remain unclarified.…”

Betanodavirus and VER Disease: A 30-year Research Review

“…This is the case of BB derived from the brain of Asian sea bass/barramundi and BMGB from brown marbled grouper brain, but they differ in the mechanism supporting viral persistence. Thus, whereas increased Mx expression was observed in BB cells [263], in BMGB persistence was not associated with Mx expression [264].…”

Characterization and virus susceptibility of a continuous cell line derived from the brain of Aequidens rivulatus (Günther)

“…As nestin (Chen et al, ) and nkx6‐2 (Guner & Karlstrom, ) are brain neural stem/progenitor cells markers, the results confirmed that ARB8 cells derived from neural stem/progenitor cells in the brain of A. rivulatus . The optimal temperatures for the growth of ARB8 cells range from 25 to 30°C, which are similar to those required for cell lines derived from tropical and subtropical fishes (Hasoon et al, ; Imajoh et al., ; Ishaq Ahmed et al., ; Lu, Lannan, Rohovec, & Fryer, ; Ma et al., ; Wen, ,b; Wen et al., , ). ARB8 cells proliferated considerably in the medium containing 5% FBS; therefore, the cell culture cost of these cells was lower than that of cells grown in the medium containing 10% FBS.…”

“…ARB8 cells showed resistance to GNNV‐K1, KHV, HVA and MEPyV, in contrast to the megalocytiviruses, MEIPNV1310 and CSV. It is reasonable because herpesviruses and MEPyV have a high level of host specificity (Hanson et al, ; Wen et al., ), whereas betanodaviruses may persistently infect without an apparent CPE (Chi et al, ; Wen, ). Even though betanodaviruses have caused mass morality in many marine and freshwater fish species worldwide, no pathogenicity has been reported in freshwater ornamental fishes.…”