• Parasites, Hosts and Diseases
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• v.40 no.3
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• pp.113-117
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• 2002

We investigated the sero-prevalence of toxocariasis among healthy Korean adults in 1999. A total of 314 sera from normal inhabitants in Whachon-gun, Gangwon do, Korea was examined for specific antibody levels against excretory-secretory products of second stage larvae of Toxocara (TES). The presence of cross-reactions with other helminthiases such as cysticercosis, paragonimiasis, sparganosis or clonorchiasis was also checked by specific IgG ELISA. Sera showing positive reaction against TES were also tested by IgG immunoblot and by IgE ELISA. Out of 314 subjects, 16 was found to be positive by TES IgG ELISA and immunoblot, among whom 12 were also positive by TES IgE ELISA. Among the 16 seropositive samples, two sera showed positive reaction against Paragonimus and sparganum antigen, respectively. These results inferred that cross-reactions were negligible between toxocariasis and other helminthiases. Toxocariasis seroprevalence among Korean rural adults was detected to be approximately 5%.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.95-98
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• 2000

An immunochemical method has been develooped as the most sensitive tool for studying the expression of quinoproteins containing pyrroloquinoline qinone(PQQ) in E. coli. The PQQ was conjugated to bovine serum albumin (BSA), and the conjugant was purified by using a $KwikSep^{TM}$ dextran desalting column chromatography. The PQQ-BSA conjugant was immunized to rabbits, and the IgG fractions of the antisera were purified. The most sensitive antibody against PQQ-BSA conjugant recognized some nanogram quantity of the antigen on the blot, but had little cross reactivity with BSA. Using this batch of the antibody, all the immunochemical assays of quinoproteins in E. coli were preformed. Some six different PQQ-specfic spots were detected by Western blot analysis of the soluble proteins in E. coli were performed. Some six different PQQ-specific spots were detected by Western blot analysis of the soluble proteins in E. coli after two-dimensional gel electrophoresis. Their molecular weights on the blot were estimated to be about 100-, 90-, 72-, 58-, 52-, and 50kDa. Their pI values fell in the range from 4.8 to 5.5. These results stronly suggest that quinoproteins are present in E. coli, and that the protein moieties were covalently bound to PQQ.

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.377-392
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• 1987

Monoclonal antibody to the Escherichia coli heat-stable enterotoxin(ST) was produced to develop a rapid and convenient diagnostic method to the ST. The toxin was purified from culture supernatant of enterotoxigenic E. coli O148H28($ST^+/LT^+$) and conjugated to bovine serum albumin(BSA). The ST-BSA conjugate was used to immunize BALB/c mice and the immune spleen cells from these mice were fused with $P3{\times}63$ Ag8.V653 plasmacytoma cells. Hybridomas were screened by ELISA and positive hybridomas were cloned by limiting dilution. Finally, one stable clone (AS36) specific to ST was selected for further growth and characterization. Antibody titers of culture supernatant and ascitic fluid from BALB/c mice were 1:1,024 and 1:20,480 respectively in ELISA. The isotype and subclass of monoclonal antibody was IgG1 in sandwich ELISA. To test the neutralizing effect of monoclonal antibody on toxin activity of ST, mixture of ascitic fluid and ST was assayed by infant mouse assay and this monoclonel antibody was proved to be a neutralizing antibody. The titer of ascitic fluid which completely neutralized biological activity of 4 units of ST was 1:4. Purified ST was quantitatively measured by competitive ELISA and minimum amount of ST detectable by this assay was 250pg, which was an amount six-fold smaller than that detectable by infant mouse assay. Four reference strains of enterotoxigenic E. coli from WHO were detected by competitive ELISA and highly specific, sensitive and reproducible result was obtained.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.13 no.1
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• pp.60-77
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• 2000

Experimental studies were done to research effects of Leejungtang and Leejungtanggamibang on the anti-allergic effects. We studied the vacular permeability response induced by histamine and serotonin, homologous PCA provoked by IgE-like antibody against EWA, contact dermatitis induced by picryl chloride and delayed type hypersensitivity response to SRBC. The results were obtained as follows: 1. In effects of the Leejungtang and Leejungtanggamibang on the vascular permeability responses to intradermal serotonin, the Leejungtang revealed insignificant effect and Leejungtanggamibang revealed significantly inhibitory effect. 2, In effects of the Leejungtang and Leejungtanggamibang on the vascular permeability responses to intradermal histamine, the Leejungtang revealed insignificant effect and Leejungtanggamibang revealed significantly inhibitory effect. 3. In the homologous PCA provoked by IgE-like antibody against white albumin, the Leejungtang revealed insignificant effect and Leejungtanggamibang revealed significantly inhibitory effect. 4. In the delayed type hypersensitivity responses to picryl chloride, the Leejungtang revealed insignificant effect and Leejungtanggamibang revealed significantly inhibitory effect. 5. In the delayed type hypersensitivity responses to sheep red blood cell the Leejungtang revealed insignificant effect and Leejungtanggamibang revealed significantly inhibitory effect.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1665-1670
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• 2006

The objective of this research was to provide the characterization and method for producing anti-E. coli O157:H7 antibodies in egg-laying hens and to determine if the antibody can restrain the proliferation of E. coli O157:H7 in-vitro. Selected antigenic fractions (whole cell, outer membrane protein and lipopolysaccharide (LPS)) from E. coli O157:H7 were injected to hens in order to produce anti-E. coli O157:H7 antibodies. The immune response and the egg yolk antibodies of laying hens against the whole cell, outer membrane protein and LPS antigens were monitored by ELISA. The level of antibodies against whole cell antigen monitored through ELISA sharply increased after the initial immunization, and it was found to be maximum on day 49 however, the level was maintained up to day 70. Antibodies (5 mg/ml) directed against the whole cell inhibited E. coli proliferation 10-13 times more than outer membrane protein or LPS. The antibody response against the whole cell antigens appeared to have higher activity in restraining the proliferation of E. coli O157:H7 than antibody against outer membrane protein or LPS. Results reflected that increasing the IgY's in the egg yolk could prevent greater economic losses due to human and animal health from pathogenic bacteria i.e. E. coli O157:H7.

• BMB Reports
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• v.30 no.6
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• pp.431-437
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• 1997

Since the role of CD40 on the interleukin-4(IL-4) -induced B cell activation has been strongly implicated in the agumentation of IgE production and response, we have investigated the intracelluar signaling pathways utilized by IL-4 and CD40 for type II IgE receptor (CD23) expression. IL-4 and anti-CD40 antibody treatment of human B cells, independently caused a rapid induction of CD23 gene activation within 2 h. There was a noticeable synergism between the action of the two agents inducing CD23 expression: the addition of anti-CD40 to the IL-4-treated culture significantly agumented the IL-4-induced CD23 on both mRNA and surface protein levels, and the inclusion of IL-4 in the anti-CD40-treated cells caused a further increase of CD23 expression far above the maximal level induced by anti-CD40. Protein tyrosine kinase (PTK) inhibitors effectively suppressed the both IL-4- and anti -CD40-induced CD23 expression. whereas protein kinase C (PKC) inhibitors had no effects. Electrophoretic mobility shift assays (EMSA) have shown that IL-4 and anti-CD40 induce the activation of NF-IL-4 and $NF-_{K}B$, respectively, binding to the CD23 promoter, both in a PKC-independent and PTK-dependent manner. These data suggest that the synergistic activation of CD23 gene expression by IL-4 and anti-CD40 is mediated by co-operative action of distinct nuclear factors. each of which is rapidly activated via PKC-independent and PTK-dependent process.

• Biomedical Science Letters
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• v.5 no.2
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• pp.147-153
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• 1999

The changes of antibody titer were observed in rats which were experimentally infected with Echinostoma hortense metacercaria. Serum levels of IgG and IgM were measured by enzyme-linked immunosorbent assay (ELISA). The mean absorbance values obtained for specific-IgG were from 0.130$\pm$0.014 (mean$\pm$S.D.) to 0.480$\pm$0.073. The peak appeared in the 4th week after infection, then declined slowly during the 5th and 6th week, although mild elevation apperared in the 8th week. The mean absorbance values of specific-IgM were detected from 0.160$\pm$0.034 to 0.409$\pm$0.084. The peak value (0.409$\pm$0.084) was on the 14th day after infection, then declined on the 8th week. Results showed that the assay could be used for detection of E. hortense infection in experimentally infected rats or laboratory experiments where evidence of infection is required.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.1
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• pp.61-68
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• 2003

Streptococcus mutans is known to be a major causative organism of human dental caries. The development of a vaccine against dental caries involves identification of appropriate antigens of mutans streptococci against which protective immune responses can be mounted, and the selection of a method of immunization that will generate sustained levels of protective antibodies. Antigens receiving most attention include streptococcal surface proteins that are involved in attachment to tooth surfaces and glucosyltransferases (GTF) that synthesize adhesive glucans from sucrose. The induction of antibody responses to orally administered antigens is often difficult due to digestive destruction of antigens and immune tolerance. Here we report the induction of antibody responses to an anti-caries vaccine containing retinoic acid (RA). Subcutaneous immunization with formalin-fixed bacteria or GTF supplemented with RA induced higher serum IgM and IgA responses to GTF compaired to oral adminstration. Antisera induced by Ingbritt strain showed partial cross-reaction with LM-7 strain, but not with OMZ175. These results suggest that subcutaneous immunization with GTF combined with an immunomodulator, RA, may be applied to anti-caries vaccine.

• IMMUNE NETWORK
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• v.4 no.1
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• pp.7-15
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• 2004

Background: The heat shock proteins (HSPs) play an important role in cellular protection mechanisms against physical or chemical stresses. In this study scFv antibodies specific for human HSP70.1 were isolated from a semi-synthetic human scFv library with the ultimate goal of developing anti-HSP70.1 intracellular antibody (intrabody) that may offer an attractive alternative to gene targeting to study the function of the protein in cells. Methods: A semi-synthetic human scFv display library ($5{\times}10^{8}$ size) was constructed using pCANTAB-5E vector and the selection of the library against bacterially expressed recombinant human HSP70.1 was attempted by panning. Results: Three positive clones specific for recombinant HSP70.1 were identified. All three clones used $V_{H}$ subgroup III. On the other hand, $V_{L}$ of two clones belonged to the kappa light chain subgroup I, but the other utilized $V_{k}$ subgroup IV Interestingly, these scFv molecules specifically reacted to the recombinant HSP70.1, yet failed to recognize native HSP70 induced in U937 human monocytic cells by heat treatment. Conclusion: Our results indicated that affinity selection of an scFv phage display library using recombinant antigens produced in E. coli might not guarantee the isolation of scFv antibody molecules specific for a native form of the antigen. Therefore, the source of target antigens needs to be chosen carefully in order to isolate biofunctional antibody molecules.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.483-489
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• 2002

The role of $G{\alpha}12\;and\;G{\alpha}13$ in modulating the IgE receptor-mediated histamine secretion in the streptolysin-o-permeabilized human cultured mast cell was investigated. The expression of $G{\alpha}12\;and\;G{\alpha}13$ proteins were regulated during human cultured mast cell differentiation, and a significant correlation was observed between the levels of expression of $G{\alpha}12\;and\;G{\alpha}13$ proteins and IgE receptor-mediated histamine secretion capability in human cultured mast cells. Antibodies against $G{\alpha}12\;and\;G{\alpha}13$ effectively inhibited the IgE receptor-induced histamine release, and the concentration of anti-$G{\alpha}12$ antibody used to inhibit histamine secretion was shown to also inhibit the IgE receptor-mediated elevation of intracellular $Ca^2+$. Therefore, the results suggest that $G{\alpha}12\;and\;G{\alpha}13$ play roles in modulating IgE receptor-activated $Ca^2+$ influx, thereby regulating histamine release in cultured human mast cells. This is the first report to show that $G{\alpha}12\;and\;G{\alpha}13$ are involved in the regulation of $Ca^2+$ mediated exocytosis in human cultured mast cells.