• Journal of fish pathology
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• v.22 no.3
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• pp.219-228
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• 2009

The genomic and subgenomic RNAs of fish nodavirus encode the four proteins, protein A, capsid protein, non-structural protein B1 and B2. In this study, we describe the immune response of olive flounder Paralichthys olivaceus immunized with live fish nodavirus or recombinant capsid protein, non-structural protein B1 and B2 expressed in E. coli. Nodavirus-infected flounder produced antibodies to capsid protein, B1 and B2 and nodavirus-neutralizing activities were detected in the serum of the nodavirus-infected flounder. The flounder were immunized against the three recombinant proteins of fish nodavirus and the sera from these immunized fishes were assayed for nodavirus-specific antibody by ELISA and a neutralization test. In the immunized flounder, all three recombinant proteins induced the production of similar levels of antibody, but only the antibody to capsid protein significantly neutralized nodavirus. These results indicate that all three nodaviral proteins are immunogenic in flounder, but only the capsid protein can induce neutralizing antibody against nodavirus.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.293-299
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• 2008

To screen the differentially expressed genes in cadmuim-exposed marine medaka fish (Oryzias javanicus), a candidate marine test fish for ecological toxicity, the differential display polymerase chain reaction (DD-PCR) was carried out, since the genome-wide gene expression data are not available in this fish species yet. A total of 35 clones were isolated from cadmium-exposed fish and their nucleotide sequences were analyzed. The differentially expressed gene candidates were categorized to response to stimulus (3); ion binding (3); DNA binding (1); protein binding (6); carbohydrate binding (1); metabolic process (4); biological regulation (3); cellular process (2); protein synthesis (2); catalytic activity (2); sense of sight (1); immune (1); neurohormone (1); signaling activity (1); electron carrier activity (1) and others (3). For real-time quantitative RT-PCR, we selected catalase, glucose-6-phosphate dehydrogenase, heat shock protein 70, and metallothionein and confirmed that cadmium exposure enhanced induction of these four genes.

• Journal of fish pathology
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• v.24 no.3
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• pp.269-278
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• 2011

Gene expression of two glyceraldehyde-3-phosphate dehydrogenase (GAPDH) paralogs was examined during Edwardsiella tarda challenge and heavy metal exposures in mud loach (Misgurnus mizolepis; Cypriniformes) kidney and spleen. Transcription of the two mud loach GAPDH paralogs (mlGAPDH-1 and mlGAPDH-2) was significantly modulated by these stimulatory challenges in an isoform-dependent manner. Based on the real-time RT-PCR analysis, the mlGAPDH-2 transcripts were more preferentially induced by E. tarda challenge, whereas the mlGAPDH-1 transcripts were proven to show more inducibility in response to heavy metal exposure using Cd, Cu, Mn and Zn at $5{\mu}M$. Their isoform-specific response patterns were closely in accordance with the TF binding profiles in promoter and intron-1 of the two mlGAPDH isoforms, in which the mlGAPDH-2 has more binding sites for immune-related transcription factors than mlGAPDH-1 while the mlGAPDH-1 possesses exclusively metal responsive elements in its intron. Collectively, the mlGAPDHs are potentially involved in cellular pathways independent of glycolysis and the two GAPDH paralogs might undergo functional diversification or subfunctionalization at least at the transcription level.

• Journal of fish pathology
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• v.22 no.3
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• pp.353-366
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• 2009

We constructed a rock bream Oplegnathus fasciatus leukocyte cDNA library and a total of 795 expressed sequence tag (EST) clones were generated. Gene annotation procedures and homology searches of the sequenced ESTs were locally done by BLASTX for amino acid similarity comparisons. Of the 795 EST clones, 491 different ESTs showed significant homology to previously described genes while 304 ESTs were unidentified, hypothetical, or unnamed proteins. Encoding 121 different sequences were identified as putative bio-defense genes or genes associated with immune response.

• Journal of fish pathology
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• v.13 no.2
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• pp.103-110
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• 2000

The immunostimulatory effects of quaternary ammonium compounds(QACs) were investigated in leucocytes of eel(Anguilla japonica) in vitro. Proliferation of peripheral blood lymphocytes(PBLs) was no significantly affected by QACs, regardless of mitogen(PHA, ConA and LPS) and the concentration of QACs added. QACs heightened the leucocytes function such as respiratory burst activity, phagocytosis and pinocytosis, resulting in significantly increased the bactericidal activity of macrophages. These results suggested that QAC might modulate the immune responses by activation of leucocytes function but not by increment of immunocompetent cell numbers.

• Journal of fish pathology
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• v.35 no.1
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• pp.121-128
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• 2022

Recent studies revealed that histone proteins are involved in innate immune responses during pathogen invasion as well as DNA packing. This study characterized the histone genes (H2A.V) of sevenband groupers and analyzed gene expression in NNV-infected sevenband groupers. The open reading frame (ORF) of H2A.V is 387 bp which encoded 128 amino acid residues. The deduced amino acid sequence of H2A.V harbor a highly conserved domain for H2A/H2B/H3 and H2A_C binding domain. Quantitative real-time PCR analysis showed that H2A.V had a high gene expression level in the brain and blood after being NNV-infected. An increase in extracellular histone protein in the blood has been identified as a biomarker for vascular function in humans. More research is required to understand histone's immune response at the protein level or in aquatic animals.

• Journal of fish pathology
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• v.36 no.2
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• pp.361-368
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• 2023

Juveniles of the white leg shrimp Litopenaeus vannamei (Weight 0.18±0.08 g) were exposed to nitrite-N at 0, 25, 50, 100, 200 and 400 mg/L for 72 hours, and the lethal concentration, heamolymph and genes regulation were evaluated. The lethal concentration 50 (LC₅₀) of L. vannamei exposed to nitrite-N was 141.2 mg/L at 25℃ and 33 psu. In Total protein, total cholesterol, and BUN in heamolymph temporarily increased after the start of the experiment and then stabilized, but glucose, an indicator of stress, decreased over time in the entire experimental group, and creatines, an indicator of tissue damage, decreased with nitrite concentration until the first 12 hours. The genes of immune-related showed that masquerade-like serine proteinase(Mas) increased at 50 and 400 ppm for 24 hours, and then gradually decreased depending on concentration. In the case of prophenoloxidase, it was highest at 400 ppm for 40 hours, and other genes(Ras-related nuclear protein, Masquerade-like serine proteinase, proPO-activating enzyme) showed a response for 48 hours and then gradually decreased. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of L. vannamei.

• Journal of Nutrition and Health
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• v.21 no.1
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• pp.36-46
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• 1988

This study was carried out to investigate the effects of different protein and fat levels on the growth and on immune response in rats. In experiment 1, Sprague-Dawly male rats were fed diets containing 6%, 15%, or 30% casein with 2 levels of fat(2% and 30%) at each protein level. In experiment 2 and 3, rats were devided into 8 diet groups ; 4 different sources of proteins(casein, meat protein, fish protein, and gluten) were used at 15% level of the diet with 2% or 30% of dietary fat. The results show as follows 1) The rats in 6% casein group showed lower body weight gain and organ weight than those in 15% and 30% casein groups. There was no significant difference between 15% and 30% casein groups. In experiment 2, the gluten diet group showed the lowest growth rate and epididymal fat pad weight among 4 different dietary protein groups regardless the level of dietary fat. 2) There was no significant difference in immune response according to the sources and levels of dietary protein. However, the rats fed high fat diet showed the lower plaque-forming cell response than those fed low fat diet regardless dietary protein.

• Journal of Microbiology and Biotechnology
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• v.29 no.8
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• pp.1324-1334
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• 2019

Fish mycobacteriosis is a common bacterial disease in many species of freshwater and marine fish and has caused severe loss of fish production. Mycobacterium marinum has been the most prevalent pathogen observed in several outbreaks of mycobacteriosis of farmed sturgeons in China. However, the immune responses and pathology of sturgeons in mycobacterial infection are rarely studied. Therefore, we used the Illumina RNA-seq method to analyze the transcriptome profile of Acipenser schrenckii challenged with Mycobacterium marinum. To begin, 168,220 non-redundant contigs were acquired from the infection and control groups, and among these, 33,225 contigs have acquired annotations. A total of 4,043 differently expressed (DE) contigs between the two groups were identified, and among these, 2479 were up-regulated and 1564 were down-regulated in the infected fish. A total of 1,340 DE contigs with acquired annotations in KEGG were enriched for 124 pathways including the TNF signaling pathway, and the Toll-like receptor signaling pathway. The roles of DE genes involved in significant pathways and other processes were discussed. The 2,209 DE contigs that have yet to acquire proper annotation may represent candidate genes associated with infection in sturgeons and are expected to serve as immunogenetic resources for further study. To our best knowledge, this is the first transcriptome study on sturgeons under bacterial infection.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.446-446
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• 2000

Specific polyclonal and/or monoclonal antibodies (MAbs) to immunoglobulins (Igs) and their subunits have proved to be valuable tools in immunological research and in immunological assays. In this study, we developed and characterized MAbs against flounder serum Igs. To obtain the pure flounder serum Igs, mouse IgG (mIgG) was immunized to flounder. Flounder Igs were purified by using mIgG-agarose affinity column chromatography. The structure of purified flounder Ig was observed, on denatured SDS-PAGE, to be composed of two heavy chains (77 and 72 kd) and two light chains (28 and 26 kd). MAbs were produced by fusion of myeloma cells (SP2/0) with Balb/c mouse spleen cells previously primed with the flounder Igs. Finally, three hybridoma clones, FIM 511, FIM 519 and FIM 562 were established to recognize both 2 heavy chains, 26 kd of light chain and 28 kd of light chain, respectively. On the other hand, the flounder immune sera collected on the weekly basis were tested on ELISA and immunoblot analysis whether boosting effect is present in flounder humoral immune system. As a result, the secondary immune response in flounder was ascertained on ELISA, but not on immunoblot analysis. Further, we observed an alteration of serum protein levels following immunization. Our MAbs and basic information on flounder humoral immune system obtained in this study will be helpful to control and monitor the efficiency of fish vaccines and therapeutic process of flounder diseases.