• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.21-28
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• 2001

Enzyme linked-immunosorbent assay (ELISA) for a rapid detection of fungi, Aspergillus and Penicillium genera in food, were developed and their efficiencies were approved by detecting artificially contaminated agricultural commodities. Mice were immunized with partially purified Aspergillus flavus extracellualr polysaccharide (EPS) and lymph node cells of the mice were fused with the myeloma cells for production of monoclonal antibodies. Mab 1G11, one of the antibodies, was selected and purified. A sandwich ELISA was established and its detection limit toward A. flavus EPS was 1mg/ml. Among the 59 strains tested (including 18 species of Aspergillus, 16 of Penicillium, 11 of Fusarium, 1 of Absidia, 2 of Alternaria, 2 of Candida, 2 of Cladosporium, 2 of Geotrichum, 2 of Mucor, 2 of Rhizopus, 1 of Trichoderma), species of Aspergillus and penicillium had a high reactivity with Mab 1G11 even up to 10,000 times dilution of culture broths. The other genera except Cladosporium resinae showed no reactivity, thus Mab 1G11 was specific to the genera of Aspergillus and Penicillium. The epitope of A. flavus EPS against monoclonal Mab 1G11 was on the carbohydrate moiety when 1 to 100$\mu g/g$ A. flavus EPS were put into rice, potato, and mandarin orange, the average recoveries detected by sandwich ELIA were 123, 59, and 76%, respectively. Correlation was found to be linear between the EPS, and mycelium of A. flavus and Penicillium citrinum grown in a liquid medium (r=0.87 and 0.96), and also between the EPS and colony forming unit in solid media of rice of potato (r=0.91-0.99).

• Journal of fish pathology
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• v.24 no.1
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• pp.39-45
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• 2011

The specific antibody response of olive flounder, Paralichthys olivaceus to different water temperature were tested by enzyme-linked immunosorbent assay (ELISA). In the rearing temperature of $15^{\circ}C$, first anti-bovine serum albumin (BSA) antibody titer was appeared after 14 days of immunization, whereas 24~48 days post-immunization (PI) resulted maximum antibody titer in all 5 experimental fish with optical density (OD) values 1.94~3.04. At the end of the experiment (84 days), 0.03~1.28 OD values were observed. In the rearing temperature of $12{\sim}13^{\circ}C$, first antibody titer was found 28 days PI in 2 out of 5 fish. Three fish shown high OD titer (1.88~2.68) between 56 and 70 days and OD values of 0.49 to 2.35 were observed at 84 days. However, the anti-BSA antibodies of two fish showed less than 0.8 OD values until 84 days. In the rearing temperature of $10^{\circ}C$, specific antibody appeared at 56 days, maximum antibody titer was observed at 70 days in 2 out of 5 fish (OD values: 1.37~1.53) and 1.00 to 1.11 OD values were observed at 84 days. Rest 3 fish showed OD values of 0.12 to 0.68 much below to that of other 2 fish, throughout the experimental period. In conclusion, specific antibody response of olive flounder at high temperature was much faster, higher and longer than that at lower temperature.

• Korean Journal of Poultry Science
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• v.38 no.4
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• pp.323-330
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• 2011

The chicken monoclonal antibody (mAb), 13C8, reacts with sporozoite antigens of Eimeria spp. which causes avian coccidiosis. Since this mAb was produced at low amount due to genetic instability of chicken hybridoma, a recombinant 13C8 single-chain Fv (ScFv) antibody was constructed by amplification of the variable domain of heavy (VH) and light chain (VL) genes of antibody derived from chicken hybridoma. The constructed 13C8 ScFv was successfully expressed in E. coli and purified as a soluble form. In ELISA analysis, this recombinant 13C8 ScFv antibody showed antigen binding activity as the original mAb. In addition, nucleotide sequence comparison of 13C8 gene to the germline chicken VL and VH genes suggested that the gene conversion with $V{\lambda}$ and VH pseudogenes might contribute to the diversification of VL and VH genes in chickens.

• Parasites, Hosts and Diseases
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• v.30 no.2
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• pp.125-132
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• 1992

This study was performed to observe the cell-mediated and humoral immune responses in mice which were infected with Beverley, Fukaya and ME49 strain of Toxoplasma gondii, respectively. The blastogenic responses of splenocytes using $[^3H]-thymidine$ and serum antibody titers were measured weekly up to 10 weeks after infection. The blastogenic responses of splenocytes treated with concanavalin A and Tosoplasma Iysate were significantly declined in the 3 strain groups as compared with the non-infected group (P<0.05), however lipopolysaccharide-treated blastogenic responses were not significantly different between infected and non.infected groups. The serum IgG antibody titers in the three infected groups increased from 2 weeks after infection, and the serum IgM antibody titers increased until 4 weeks after infection. No significant differences were revealed in blastogenic responses and serum antibody titers among the 3 groups. The present study suggested that cell-mediated immune responses were involved in T. gondii infected mice and blastogenic responses of T Iymphocytes were inhibited in acute T. gondii infection.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.133.1-133
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• 2003

Gummy stem blight, caused by Didymella bryoniae occurs exclusively on cucurbits. This fungus has been known not to produce its pycnidium in vitro unless irradiated. Through this study, we optimized cultural conditions for mass-production of pycnidiospore by Metal Halide Lamp irradiation. In brief, the mycelial was cultured at $26^{\circ}C$ on PDA, for 2 days under the darkness, and then the plate was illuminated with MH lamp continuously for 3-4 days at $26^{\circ}C$, a great number of pycnidia was simultaneously formed. Thus produced pycnidiospores were used as immunogen. From fusions of myeloma cell (v-653) with splenocytes from immunifed mice were car ried out. And, two hybridoma cell lines that recognized the immunogen Didymella bryoniae were obtained. One Monoclonal Antibody, Db1, recognized the supernatant and the other monoclonal antibody, Db15, recognized the spore. Two clones were selected which were used to produce ascite fluid two MAb Db1 and Db15, were immunotyped and identified as IgG1 and IgG2b, respectively. Titer of MAb Db1 and MAb Db15 was measured absorbance exceeded 0.5 even at a $10^{-5}$ dilution. The MAbs reacted positively with Didymella bryoniae but none reacted with other of fungi and CMV, CGMMV Sensitivity of MAb was precise enough to detect spore concentration as low as $10^{3}$ well by indirect ELISA characterization of the MAb Db1, Db15 antigen by heat and protease treatments show that the epitope recognized by the MAb Bb1, Db15 were a glycoprotein.

• BMB Reports
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• v.36 no.5
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• pp.493-498
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• 2003

The scFv antibody towards the Burkholderia pseudomallei exotoxin was previously constructed by phage display and exhibited good specificity towards the exotoxin. We report here the optimization of the scFv expression in an E. coli expression system. Four different E. coli strains (ER2537, TG1, HB2151, and XL1-Blue) were examined for optimal expression of the scFv protein. Two types of carbon source (i.e. 0.2% glucose and 0.2% glycerol) were also tested for their ability to induce the scFv expression. Cells that carried the scFv construct were grown at $30^{\circ}C$ and induced with 0.05 mM IPTG. The expression was then monitored by SDS-PAGE, Western blotting, and indirect ELISA. The Western blot profile showed different levels of the scFv expression among the host strains; XL1-Blue exhibited the highest level of the scFv protein expression. Glycerol at a concentration of 0.2% (v/v) significantly increased the scFv protein expression level when compared to 0.2% (w/v) glucose. Further optimization demonstrated that the scFv protein expression in XL1-Blue was the most optimal with a glycerol concentration as low as 0.05%. However, by indirect ELISA, only the scFv protein that was expressed in 0.2% (v/v) glycerol exhibited high specificity towards the Burkholderia pseudomallei exotoxin.

• The Journal of the Korean Society for Microbiology
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• v.21 no.3
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• pp.387-391
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• 1986

Serum samples from 51 patients with clinically suspected typhoid fever were tested for immunoglobulin G (IgG), IgM and IgA antibodies against the whole bacteria antigen of Salmonella typhi by an enzyme-linked immunosorbent assay. The levels of IgG and IgA antibody to-whole bacteria antigen were higher in the culture-proven patients than in controls. The levels of IgM antibody to- whole bacteria antigen showed better discrimination between culture negative patients and controls than those of IgG or IgA antibody to-whole bacteria antigen. The enzyme-linked immunosorbent assay was much more sensitive than the Widal test. It would be a useful tool for the diagnosis of typhoid fever with a single serum sample.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.341-356
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• 1993

In the prevention of root surface caries, antimicrobial therapy for the control of subgingival and supragingival plaque is seriously considered as a long term suppression of pathogenic microflora. Recently, varnishes containing antimicrobial agents have been developed to control the supragingival microflora. The purpose of this study was to determine the antimicrobial effects of 20% chlorhexidine varnish and 2.6% silane fluoride varnish with sealant. In clinical experiments, 12 subjects were selected from the periodontally treated patient and divided into 3 groups. After a dental prophylaxis, the subjects were treated with single application of placebo varnish (group I), 20% chlorhexidine varnish (group II), and 2.6% silane fluoride varnish (group III). Root surface plaque samples were taken before (baseline) and one, two, four, and 8 weeks after the treatments. Microbiological examinations of root surface plaque were performed with culture study and indirect immunoflorescence (I.I.F.) study, and immunological examination of gingival crevicular fluid antibody titers was performed with ELISA study. The results were as follows: 1. Pathogenic microflora on the root surface including S. mutans, S. sanguis, S. mitis, A. naeslundii, A. viscosus were 24 - 37% on I.I.F. study. 2. S. mutans, S. sanguis, S. mitis, A. naeslundii, A. viscosus of the root surface plaque was significantly reduced from 1 week to 8 weeks after antimicrobial varnish treatment, but showed generally increasing tendency in control group. 3. Gingival crevicular fluid antibody titers were significantly reduced from 1 or 2 weeks to 4 weeks after antimicrobial varnish treatment.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.114-126
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• 2019

This paper introduces three ways to determine host-guest complexation of cucurbit[7]uril (CB[7]) with homocysteine (Hcy). After preincubating Hcy and cysteine (Cys) with CB[7], Ellman's reagent (DTNB) was used to detect Hcy and Cys. Only Cys reacted with DTNB and Hcy gave a retarded color change. This suggests that the -SH group of Hcy is buried inside CB[7]. Human cystathionine ${\gamma}-lyase$ (hCGL) decreased the level of Hcy degradation after preincubating Hcy and CB[7]. These results suggest that the amount of free Hcy available was decreased by the formation of a Hcy-CB[7] complex. The immunological signal of anti-Hcy monoclonal antibody was decreased significantly by preincubating CB[7] with Hcy. The ELISA results also show that ethanethiol group ($-CH_2CH_2SH$) of Hcy, which is an epitope of anti-Hcy monoclonal antibody, was blocked by the cavity in CB[7]. Overall, CB[7] can act as a host by binding selectively with Hcy, but not Cys. The calculated half-complexation formation concentration of CB[7] was 58.2 nmol using Ellman's protocol, 97.9 nmol using hCGL assay and 87.7 nmol using monoclonal antibody. The differing binding abilities of Hcy and Cys towards the CB[7] host may offer a simple and useful method for determining the Hcy concentration in plasma or serum.

• IMMUNE NETWORK
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• v.10 no.1
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• pp.5-14
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• 2010

Background: There have been several reports describing the capability of ginseng extracts as an adjuvant. In this study, we tested if ginsan, a polysaccharide extracted from Panax ginseng, was effective in enhancing antibody response to orally delivered Salmonella antigen. Methods: Ginsan was treated before oral salmonella antigen administration. Salmonella specific antibody was determined by ELISA. mRNA expression was determined by RT-PCR. Cell migration was determined by confocal microscopy and flow cytometry. COX expression was detected by western blot. Results: Ginsan treatment before oral Salmonella antigen delivery significantly increased both secretory and serum antibody production. Ginsan increased the expression of COX in the Peyer's patches. Various genes were screened and we found that CCL3 mRNA expression was increased in the Peyer's patch. Ginsan increased dendritic cells in the Peyer's patch and newly migrated dendritic cells were mostly found in the subepithelial dome region. When COX inhibitors were treated, the expression of CCL3 was reduced. COX inhibitor also antagonized both the migration of dendritic cells and the humoral immune response against oral Salmonella antigen. Conclusion: Ginsan effectively enhances the humoral immune response to orally delivered antigen, mediated by CCL3 via COX. Ginsan may serve as a potent vaccine suppliment for oral immunization.