• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.91-95
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• 1993

To investigate hemolysin from Vibrio vulnificus in terms of protein chemistry and immunochemistvy, the simple method to produce antiserum was developed as follows ; Crude hemolysin from Vibrio vulnificus was mixed with cholesterol-phosphatidylcholine-liposome. Only hemolysin with molecular weight of 50kD was selertively bound to the liposome. Thus, without purification of crude hemolysin, liposome bound hemolysin was used as antigen to produce antiserum by injecting into back muscle of a rabbit. Resultant antiserum reacted only with hemolysin. Hemouysin of Vibrio vulnificus from patients and environment was formed single band in gel diffusion precipitation reaction with antiserum.

• 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 Food Hygiene and Safety
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• v.8 no.4
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• pp.205-214
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• 1993

The monoclonal antibody to chloramphenicol(CAP) was produced to develop an enzyme-linked immunosorbent assay(ELISA) for residual CAP. An immunogen(CAP-BSA) was prepared by immunogen, antibody titer was measured by indirect ELISA. Spleen cells form the immunized mouse were fused with SP2/OAg14 myeloma cells. Among hybridomas selected in HAT media, 6 clones shown high antibody titer to CAP were subjected to cloning by limit dilution, and all of the monoclonal antibodies(MCA1, 2, 3, 4, 5, 7 and 9) produced by each clone were identified as IgG1 by ELISA isotyping analysis. Competitive ELISA condition was established by using the purified monoclonal antibody MCA1 as primary antibody and CAP-HSA conjugate as coating antigen. Standard curve of CAP(n=28) showed that the lowest detection limit of CAP is 20ng/ml level. The cross-reactivities of the 6 monoclonal antibodies showed that CAP sodium succinate. CAP base, P-nitrophenol, and p-nitrobenzyl alcohol were 89∼178, 0.050∼2.237, 0.056∼0.794 and 0.013∼7.939%, respectively. No cross-reactivities were observed with phenylalanine, tyrosine, glutamine, thiamphenicol, neomycin, streptomycin, gentamicin, sulfamethazine, sulfathiazole, chlortetracycline and p-aminobenzoic acid.

• Food Science of Animal Resources
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• v.31 no.2
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• pp.158-165
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• 2011

A sensitive reverse transcriptase-PCR (RT-PCR) method to detect viable Escherichia coli O157:H7 in milk was established. The primer sets were designed based on the nucleotide sequences of the rfbE (per) and wbdN genes in the O157 antigen gene cluster of E. coli O157:H7. RT-PCR using five different primer sets yielded DNA with sizes of 655, 518, 450, and 149-bp, respectively. All five of the E. coli O157:H7 strains were detected by RT-PCR, but 11 other bacterial species were not. The sensitivity of RT-PCR was improved by adding yeast tRNA as a carrier to the crude RNA extract. The RT-PCR amplifying the 149-bp DNA fragment was the most sensitive for detecting E. coli O157:H7 and the most refractory to the bactericidal treatments. Heat treatment at $65^{\circ}C$ for 30 min was the least inhibitory of all bactericidal treatments. Treatment with RNase A strongly inhibited the RT-PCR of heated milk but not unheated milk. This study described RT-PCR methods that are specific and sensitive with a detection limit of 10 E. coli O157:H7 cells, and showed that pre-treating milk samples with RNase A improved the specificity to detect viable bacteria by RT-PCR.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.600-604
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• 2001

Immunoassay was used to study the detection method of irradiated shrimp. Sandwich ELISA was formatted with monoclonal antibody (Ab) (M-IgG) and polyclonal Abs (P-IgG) and polyclonal Abs (P-IgG) individually produced against brown shrimp tropomyosin (TPM) as an antigen. When M-IgG was used as a coating Ab to capture TPM, and P-IgG were used as reaction Ab against captured TPM could be detected in the range of 12.5 to 50 $\mu\textrm{g}$/mL. Detected concentrations of TPM from irradiated shrimp decreased dose-dependently, and the concentration of Ag by combination of irradiation with heating or freezing treatments also decreased. This results suggests the possibility for Sandwich ELISA, one of immunological analyses, to be applied for detecting irradiated shrimp.

• Toxicological Research
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• v.8 no.2
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• pp.191-203
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• 1992

The immunosuppressive effects of safrole were studied in female BALB/c mouse. Mice were given 100,200and 400mg safrole/kg daily for 14days and evaluated on day 15. The day 4 immunogloblin-M antibody response to T-dependent antigen, sheep red blood cells (SRBC) was inhibited dose-dependently in all doses studied. In vitro antibody response to polyclonal antigen, lipopolysaccharide (LPS) by spleen cell suspensions from safrole-treated mice were also significantly inhibited. When safrole was treated for 14days to mice, and mitogen-induced proliferation of splenocytes were assayed on day 15, there were significant suppression of responses to B-cell mitogen, LPS and T-cell mitogen concanavalin A(Con A) at a dose of 400mg safrole/kg. Direct addition of safrole on the splenocyte culture also produced a dose dependent suppression on in vitro antibody response to LPS, and mitogen-induced lymphoproliferatin at doses of 100,200,400 and 800${\mu}M$ safrole. The role of metabolic activation in safrole-induced suppression of in vitro antibody response was studied using splenocyte-hepatocyte coculture system. The suppression of in vitro antibody respose to LPS by safrole was not altered when safrole were incubated in the splenocyte-hepatocyte system for 4hr as compared with direct addition of safrole in splenocytes culture. Neither the addition of salicylamide, sulfotransferase inhibitor, nor the addation of inorganic sulfate, sulfation cofactor to the splenocyte-hepatocyte coculture, altered the suppression of antibody response by safrole. These results suggest that the immunosuppression by safrole may not by produced by the reactive metabolites which are mediated in carcinogenesis of safrole.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.287-290
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• 2015

Soyasaponins are glycosylated, which gives rise to a wide diversity of structures and functions. We evaluated for inhibitory effects of 4 soyasaponins on antigen-induced degranulation in RBL-2H3 Cells. 4 soyasaponins had shown dose-dependently inhibited histamine and ${\beta}$-hexosaminidase.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.361-373
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• 2020

Integrins such as lymphocyte function-associated antigen -1 (LFA-1) have an essential role in T cell immunity. Integrin activation, namely, the transition from the inactive conformation to the active one, takes place when an intracellular signal is generated by specific receptors such as T cell receptors (TCRs) and chemokine receptors in T cells. In an effort to explore the molecular mechanisms underlying the TCR-mediated LFA-1 activation, we had previously established a high-throughput cell-based assay and screened a chemical library deposited in the National Institute of Health in the United States. As a result, several hits had been isolated including HIKS-1 (Benzo[b]thiophene-3-carboxylic acid, 2-[3-[(2-carboxyphenyl) thio]-2,5-dioxo-1-pyrrolinyl]-4,5,6,7-tetrahydro-,3-ethyl ester). In an attempt to reveal the mode of action of HIKS-1, in this study, we did drug affinity responsive target stability (DARTS) assay finding that HIKS-1 interacted with the IQ motif containing GTPase activating protein 1 (IQGAP1), a 189 kDa multidomain scaffold protein critically involved in various signaling mechanisms. Furthermore, the cellular thermal shift assay (CETSA) provided compelling evidence that HIKS-1 also interacted with IQGAP1 in vivo. Taken together, it can be concluded that HIKS-1 interferes with the TCR-mediated LFA-1 activation by interacting with IQGAP1 and thereby disrupting the signaling pathway for LFA-1 activation.

• Journal of Life Science
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• v.9 no.3
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• pp.253-261
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• 1999

Leptin gene, an obesity gene, has been known to involve in the regulation of food intake and body weight. It is also thought to be related to the glucose metabolism, insulin secretion and type II diabetes mellitus. Recently, the production of recombinant leptin protein has been attempted for the application in the treatment of obesity and the correction of hereditary obesity and type II diabetes. In the present study, leptin cDNA was cloned from mouse fat cells by RT-PCR and prokaryotic expression of leptin was attempted in order ot prepare a leptin-specific antigen. Immunization of a rabbit with the leptin-specific antigen into a rabbit resulted in the generation of leptin-specific antiserum that could be useful in the detection of leption expressed in various tissues. The sequence of leptin cDNA prepared in the present study wa identical to the previously reported one. Transformation of E. coli(DH5a) cells with the leptin cDNA-inserted translation vector, pGEX-4T-3-leptin followed by treatment with IPTG (0.1mM) resulted in the expression of a large amount of GST-leptin fusion protein with a molecular weight of 44 KDa as an inclusion body. Denaturation of the insoluble fusion protein by 8M urea, 6M guanidium-HCI or 0.1% 2-mercaptoethanol followed by a slow oxidation could not solubilize the inclusion body. The cell extract was subjected to SDS-PAGE and GST-leptin protein electroeluted from the gel was then injected into a rabbit subcutaneously for the immunization. Anti-GST-leptin rabbit antiserum which had a cross reactivity to the GST-leptin protein was generated. Leptin protein expressed in mouse brain and fat tissues was detected by Western blot immunodetection system using the antiserum generated in the present study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1662-1667
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• 2011

Anthocyanins belong to a group of flavonoid compounds and are well known for their various health beneficial effects, which include antioxidative activities. Among them, the major anthocyanins isolated from seed coat of black soybean (Glycine max L.) were previously characterized as glycosides containing glucopyranose. Asthma is an allergic disease that is strongly associated with various immune cells, including basophils and mast cells. Eosinophils, basophils, and mast cells play important roles in allergic asthma through the release of inflammatory mediators such as asthma-specific T-helper 2 (Th2) cytokines and subsequent amplification of asthma symptoms via degranulation. Rat basophilic leukemia RBL-2H3 cells are the most common in vitro models for evaluating allergic reactions. In this study, we examined the effects of anthocyanin from seed coat of black soybean on antigen-stimulated degranulation and Th2 cytokine production in RBL-2H3 cells. Cell degranulation was evaluated by measuring the release of ${\beta}$-hexosaminidase. ${\beta}$-Hexosaminidase release and Th2 cytokine production in RBL-2H3 cells was much higher upon stimulation with IgE-antigen complex than those in untreated control cells. Anthocyanins significantly suppressed IgE-antigen complex-induced degranulation of RBL-2H3 cells and inhibited IgE-antigen complex-mediated interleukin (IL)-4, IL-13, and tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) production in RBL-2H3 cells. These findings suggest that anthocyanins from seed coat of black soybean effectively inhibit allergic reactions and may have beneficial effects against allergic asthma.