• Journal of fish pathology
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• v.12 no.1
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• pp.56-62
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• 1999

Since 1998, mass mortality of the Japanese flounder has widely occurred in the south and west coastal area of Korea. A new serotype birnavirus was isolated during the investigation of the cause of the disease. By the electromicroscopic examination, the isolated virus particles appeared hexagonal and unenveloped with an average diameter 52 to 56 nm. Birnavirus specific fragment was amplified by RT-PCR. High yield of virus (10.3 to 10.8 log $TCID_{50}/ml$) was produced in CHSE-214. RTG-2 and RTE-2 cells. Typical birnavirus CPE was observed in these cells. On the contrary, the virus CPE was not shown in the FHM and EPC cells. By a cross-neutralization test with IPNV Ab, IPNV Sp, IPNV VR-299 and MBV Y6, the isolated virus was closely related to marine birnavirus (MBV).

• Journal of Aquaculture
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• v.21 no.1
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• pp.13-18
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• 2008

Marine birnavirus(MABV) are well known fish pathogens in Asian countries such as Korea, Japan, and China. Prevalence of viral disease, geological distribution and host or reservoir of viruses were investigated from wild marine fishes in southern coast of Korea in 2003 and 2005. RT-PCR results showed that MABV were detected in 17 fishes(10.6%) from 160 fishes. Comparative analysis of the nucleotide sequences and the deduced amino acids of MABV genome from wild fishes were similar to reference strains of MABV and distinguished with IPNV strains.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.88-92
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• 2007

The effect of dexamethasone injection on the burden of marine birnavirus (MABV) in asymptomatically infected olive flounder (Paralichthys olivaceus) fingerlings was investigated. In real time PCR analysis, the threshold cycle (Ct) value of the fish injected with dexamethasone was significantly lower than that of the fish in the PBS-injected and no-handling groups. The higher amplification of the MABV gene in the dexamethasone-injected group than the 2 control groups was confirmed also by semi-quantitative RT-PCR. The results indicate an increase of MABV burden in olive flounder fingerlings after a single injection with dexamethasone.

• Journal of fish pathology
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• v.12 no.1
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• pp.49-55
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• 1999

To detect birnavirus from cultured marine fish, RT-PCR assay was developed. This method was specific for aquatic birnaviruses that include IPNV Sp., IPNV Ab, IPNV VR-299 and MBV Y6. The birnavirus gene was detected (birnavirus positive samples detected 46/50) from clinical samples signed with abdominal distension and overall darkening even though the samples gave negative results in virus isolation (birnavirus isolate with CHSE-214 cell showed 12/50).

• Journal of fish pathology
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• v.13 no.1
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• pp.53-59
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• 2000

Presence of marine birnavirus (MABV) was examined against egg and ovarian fluid, and seminal fluid from the brood stocks of flounder, Paralichthys olivaceus collected from 9 different stations around Korean peninsula. The detection rate of MABV in brood stocks flounder was observed to 34% by PCR. The mean virus titer of the PCR positive fish was $10^{2.30}$ to $10^{4.30}$ $TCID_{50}$/g(ml). By a neutralization test, all of the isolated virus were ascertained to be closely related to marine birnavirus (MABV).

• Journal of fish pathology
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• v.33 no.2
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• pp.171-175
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• 2020

We developed and subsequently characterized mouse monoclonal antibodies (mAbs) against marine birnavirus (MABV). Eight hybridoma clones secreting mAbs against MABV were established. All eight mAbs (8G6, 11C3, 15E3, 17H6, 32A6, 35A7, 38B5, and 47E3) were reacted with viral protein 3 of MABV in MABV-infected CHSE-214, whereas, no reactivity was observed in normal CHSE-214 by western blot analysis. Moreover, these eight mAbs were strongly reacted with MABV, and no cross-reactivity has been observed against other five fish viruses (hirame rhabdovirus, infectious hematopoietic necrosis virus, nervous necrosis virus, spring viraemia of carp virus, and viral hemorrhagic septicemia virus), although five mAb (11C3, 15E3, 17H6, 32A6, and 38B5) reacted with both MABV and infectious pancreatic necrosis virus by enzyme linked immunosorbent assay (ELISA). These results indicate that the mAbs can be of value in MABV detection.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.133-138
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• 2004

A lot of cultured flounders died by ascitic disease blooming during the summer season in 2002, southern parts of Korea. This study was conducted to investigate the microbial flora for the ascitic cultivated olive flounder (Paralichthys olivaceus) which were collected in the Koe-je island in the southern of Korea from July 2002 to October 2003. Three Genera (Vibrio, Photobacterium and Edwardsiella), seven species of bacteria (V. harveyi, V. alginolyticus, V. parahaemolyticus, V. carcariae, V. metschenikovii, P. damsela and E. tarda) and a fish pathogenic birnavirus (marine birnavirus, MABV) were isolated from the liver, dropsy, spleen and identified by biochemical and molecular biological characterization.

• Journal of Microbiology
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• v.38 no.1
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• pp.44-47
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• 2000

The cDNA of VP2/NS junction region on segment A of the marine birnavirus (MBV) isolated from flounder (DS strain) was amplified using the reverse transcription (RT)-polymerase chain reaction (PCR). Its cDNA nucleotide and deduced amino acid sequences were analyzed, and compared with the reference strains of MBV and infectious pancreatic necrosis virus (IPNV). Analyses of the nucleotide and deduced amino acid sequences revealed that the DS strain is very similar to the reference strains of MBV, distant from the IPNV.

• Journal of fish pathology
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• v.15 no.1
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• pp.9-16
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• 2002

The objective of the study was to clarify the mechanism of persistent infection of marine birnavirus (MABV) in various nonpermissive cell lines. It was observed in CHSE-214, RTG-2 and RSBK-2 that the virus produced at high yield with typical cytopathic effect (CPE). On the contrary, the CPE was not produced in EPC, FHM and BF-2 cells. However amount of virus protein in both permissive and nonpermissive cell lines detected by ELISA was almost the same. Electron microscopy showed virions in permissive cells but not in nonpermissive cells. From the results, it is clear that virus protein and RNA were produced in nonpermissive cells as observed in permissive cells; however, assembly of the virus particles did not occur in nonpermissive cells.

• Journal of fish pathology
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• v.22 no.3
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• pp.211-218
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• 2009

In this study, we have compared the genome of marine birnavirus (MABV) detected from starry flounder Platichthys stellatus and olive flounder Paralichthys olivaceus. A molecular analysis based on the nucleotide sequence (433 bases) of VP2-NS-VP3 region revealed that MABV (08-KU) from starry flounder showed 98% similarity with MABV Y6 isolated from Yellowtail Seriola quinqueradita in Japan (Accession no: AY283781) and with other aquabirnaviruses identify more than 76%. Comparison with MABV strains (06-KP, 08-KC) from olive flounder and MABV Y6 strain showed 97-98% sequence identities. Phylogenetic analysis was performed in order to examine the relationship among previously determined aquatic birnaviruses isolates showed that MABV and IPNV strains were classified into seven clusters. Three isolates from starry flounder and olive flounder in this study, belong to the genogroup VII including MABV Y6 strain and other aquabirnaviruses isolated from marine fish and molluscan shellfish in Japan. This report is the first description of a MABV from starry flounder in Korea.