• Journal of fish pathology
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• v.32 no.1
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• pp.45-48
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• 2019

We developed and subsequently characterized mouse monoclonal antibodies (MAbs) against recombinant VP28 structural protein (rVP28) of white spot syndrome virus (WSSV). We established six hybridoma clones secreting MAbs against rVP28: 15A11, 20G6, 31H2, 34H6, 38D1 and 43A1. All six MAbs recognized the 25 kDa of protein in gill homogenates of WSSV-infected shrimp by western blot analysis, while no reactivity was observed in gill homogenates of normal shrimp. Moreover, high enzyme-linked immunosorbent assay (ELISA) optical density (OD) values (0.8-2.68) were observed in the hemolymphs from WSSV-infected shrimp, while low OD values (less than 0.24) were recorded in the hemolymphs from normal shrimp, by using these six MAbs produced in this study. These results suggest that these six MAbs are useful for the detection of WSSV.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.248-252
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• 2005

The virions of causative virus for white spot syndrome in cultured Fresh shrimp, Penaeus chinensis were rod-shaped, double envelope. An average size of the virion was 70 nm in diameter and $250\~300$ nm in length. Histopathological test of affected stomach, heart, and lymphoid organ revealed nuclear hypertrophy. Infectivity trials carried out by injection and feeding with purified virus revealed high cumulative mortality to healthy shrimp. The twenty one different protein species were detected in the analysis of virion. The length of total DNA from the purified virus particles were detected as a single band, double-stranded DNA molecule of approximately 114 kb.

• Journal of fish pathology
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• v.35 no.2
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• pp.241-246
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• 2022

White spot syndrome virus (WSSV) is a prevalent and virulent pathogen affecting cultured whiteleg shrimp (Litopenaeus vannamei) in Korea. In this study, seven monoclonal antibodies (mAbs) (10A12, 16C3, 17G4, 21G5, 22C4, 23B6 and 24G6) were produced by using purified WSSV. The reactivity of these mAbs was analysed by Western blot (WB), indirect immunofluorescence (IIF), and lateral flow immunochromatographic assay (LFIA). WB analysis demonstrated that three mAbs (17G4, 22C4, and 23B6) reacted specifically to VP28 with an approximate molecular weight of 24 kDa, mAb 16C3 reacted with approximately 17 kDa. IIF analysis demonstrated specific fluorescence signals on gill tissues of WSSV-infected shrimp, with five mAbs (10A12, 16C3, 22C4, 23B6, and 24G6), pleopods from WSSV-infected shrimp were used for LFIA, where, two mAbs (21G5 and 22C4) exhibited positive reaction. In conclusion, it can be inferred that the mAbs usage and specificity depends on the nature of assay used for diagnosis.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.524-525
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• 2001

White spot syndrome virus (WSSV) causes the most serious epizootic in cultured penaeid shrimp. The epizootic started in 1992, and spread through east and south east Asia and into other shrrimp growing countries of the region. In order to circumvent the epizootic, in many Asian countries, freshwater prawn, Macrobrachium rosenbergii is being widely considered as an alternative species to marine shrimp. (omitted)

• Journal of fish pathology
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• v.32 no.2
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• pp.123-127
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• 2019

In this study, white spots appearing in carapace of imported white leg shrimp Litopenaeus vannamei were observed by macroscopic and microscopic examination. White spots due to white spot disease showed two types, white spots with a regular circular shape ranging from 0.4 mm to 1.7 mm and white spots with an irregular shape ranging from 0.05 mm to 2 mm. White spots due to other causes showed four types that appeared as crystalized materials in range of 100 ㎛ around the tegumental gland, as polygonal inorganic deposits ranging from 58 ㎛ to 188 ㎛, as Linear inorganic deposits ranging from 0.8 mm to 9 mm, as brownish spots ranging from 0.1 mm to 0.4 mm, and brownish spots containing melanin ranging from 0.1 mm to 2 mm. As a result, white spots occurred in imported white leg shrimp Litopenaeus vannamei were divide two type, due to white spot disease or other causes, for quarantine works.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.394-398
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• 2001

Because of the great concern over the possibility of contamination from the rod-shaped nuclear virus (PRDV) from Japan and white spot virus (WSSV) from Taiwan, most eggs used in Korean shrimp farms are currently obtained from local broodstock. In addition, the screening of imported broodstock for any viral presence at the National Fisheries Research and Development Institute is also mandatory. Nonetheless, massive mortality from white spot syndrome continues in Korea. In the present study, we present an improved PCR method to use tissue-extracted DNA instead of viral DNA extracted from a purified virus based on a sucrose density gradient, and produced results within 8 h. In 1998, this modified PCR method was able to detect that diseased Penaeus japonicus were infected within 8 h. In 1998, this modified PCR method was able to detect that diseased Penaeus japonicus were infected only with PRDV, while Fenneropenaeus chinensis were infected with both PRDV and WSSV. In 1999, PRDV and WSSV were detected in F. chinensis with signs of infection, but not with WSSV alone.

• BMB Reports
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• v.37 no.6
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• pp.726-734
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• 2004

White spot disease (WSD) is caused by the white spot syndrome virus (WSSV), which results in devastating losses to the shrimp farming industry around the world. However, the mechanism of virus entry and spread into the shrimp cells is unknown. A binding assay in vitro demonstrated VP28-EGFP (envelope protein VP28 fused with enhanced green fluorescence protein) binding to shrimp cells. This provides direct evidence that VP28-EGFP can bind to shrimp cells at pH 6.0 within 0.5 h. However, the protein was observed to enter the cytoplasm 3 h post-adsorption. Meanwhile, the plaque inhibition test showed that the polyclonal antibody against VP28 (a major envelope protein of WSSV) could neutralize the WSSV and block an infection with the virus. The result of competition ELISA further confirmed that the envelope protein VP28 could compete with WSSV to bind to shrimp cells. Overall, VP28 of the WSSV can bind to shrimp cells as an attachment protein, and can help the virus enter the cytoplasm.

• Journal of fish pathology
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• v.10 no.2
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• pp.87-95
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• 1997

Baculovirus associated with white spot syndrome (WSBV) is the causative agent of a disease with high mortalities and causes severe damage to shrimp cultures. In this study, we analyzed a recombinant clone (E3) obtained from a viral genomic library to characterize the causative agent in diseased shrimp Penaeus chinensis with white spot syndrome. According to the analysis of nucleotide sequence of E3, this clone did not showed considerable sequence homology with those of other known viruses, including baculovirus Autographa californica nuclear polyhedrosis virus (AcNPV), indicating that WSBV is a novel virus causing a serious disease in P. chinensis. Based on the sequence of E3 clone, a pair of PCR primers was designed. After 30 cycles of amplification, a specific product of the expected size was detected only if the total nucleic acids extracted from the diseased shrimp was used as a template DNA, suggesting that this method can be used to diagnose the virus infection in diseased shrimp.

• Journal of fish pathology
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• v.27 no.1
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• pp.11-16
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• 2014

The resistance against white spot syndrome virus (WSSV) infection in wild marine crab Gaetice depressus by the immunization of a recombinant glutathione-S-transferase (GST) fused VP28 protein (GST-VP28) was evaluated. The cumulative mortalities of GST-VP28 injected groups were lower than those of the control groups at 10 days of post-challenge, and the time to death of 50% crab ($TD_{50}$) was delayed by the immunization using GST-VP28. The group boosted with GST-VP28 after 2 weeks of primary immunization clearly showed longer $TD_{50}$ than non-boosted group against challenge with WSSV. This result suggests that boosting with the antigen protein elicit stronger immune responses similar to adaptive immune responses of vertebrates. However, the short $TD_{50}$ was observed in the group challenged at 3 weeks post boosting comparing to the group challenged at 1 week post boosting. This suggests that the protective strength of immunization decreased by the time.

• Journal of fish pathology
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• v.33 no.2
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• pp.139-143
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• 2020

This study investigated the disinfection effect of monopersulfate (MPS) compound against white spot syndrome virus (WSSV) by bioassay using kuruma shrimp (Marsupenaeus japonicas). A WSSV stock was prepared with muscle homogenate from WSSV-infected whiteleg shrimp (Penaeus vannamei) and its lethal dose 50% endpoint (LD50) and infectious dose 50% endpoint (SID50) were respectively determined as 10-5.63 and 10-6.79 in bioassay using kuruma shrimp, followed by PCR assays. The disinfective effect of MPS compound (1.2 ppm, 2.4 ppm, 4.8 ppm) was performed by bioassay using about 10-fold higher dilution (10-4) of WSSV homogenate. The compound resulted in WSSV inactivation by a concentration-dependent manner. In addition, 4.8 ppm of MPS completely prohibited WSSV infection. To our knowledge, this study is the first report about the usefulness of MPS as a disinfectant to WSSV.