• YAKHAK HOEJI
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• v.40 no.4
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• pp.422-427
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• 1996

The anti-Ex-A IgG was specifically labeled with stable isotopes, DL-His-2,4-$d_2$, L-Phe-$d_5$, L-Trp-$d_5$, L-Tyr-2,6-$d_2$ and L-[1-$^{13}C$]Trp, by growing hybridoma cell in serum-free medium. By use of NMR spectroscopy with selectively labeled Fab fragment, we applied a paratope mapping on antigen-antibody complex. Assignments of the observed carbonyl carbon resonances have been determined by using $^{13}C$-$^{15}N$ double labeling method in order to assign the Trp resonances. Photo CIDNP was also applied to investigate the antigen-binding site(s) on the surface residues of antibody. We found that Trp 36, which is located at the $V_H$ domain, is an important residue to bind to Ex-A, however, two Tyr on the surface of anti-Ex-A IgG plays no crucial role to bind to antigen. On the basis of these results, we demonstrate that stable isotope-aided NMR strategy can be extended to molecular structural analyses of the complex of an Fab fragment and a protein antigen.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.2
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• pp.96-103
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• 2016

Helicobacter pylori infection is acquired mainly during childhood and causes various diseases such as gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue (MALT) lymphoma, and iron deficiency anemia. Although H. pylori infection in children differs from adults in many ways, this is often overlooked in clinical practice. Unlike adults, nodular gastritis may be a pathognomonic endoscopic finding of childhood H. pylori infection. Histopathological findings of gastric tissues are also different in children due to predominance of lymphocytes and plasma cells and the formation of gastric MALT. Although endoscopy is recommended for the initial diagnosis of H. pylori infection, several non-invasive diagnostic tests such as the urea breath test (UBT) and the H. pylori stool antigen test (HpSA) are available and well validated even in children. According to recent data, both the $^{13}C$-UBT and HpSA using enzyme-linked immunosorbent assay are reliable non-invasive tests to determine H. pylori status after eradication therapy, although children younger than 6 years are known to have high false positives. When invasive or noninvasive tests are applied to children to detect H. pylori infection, it should be noted that there are differences between children and adults in diagnosing H. pylori infection.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1791-1798
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• 2006

When ginsenoside Rg5, a main component isolated from red ginseng, was incubated with three human fecal microflora for 24 h, all specimens showed hydrolyzing activity: all specimens produced ginsenoside Rh3 as a main metabolite, but a minor metabolite $3{\beta},12{\beta}$-dihydroxydammar-21(22),24-diene (DD) was observed in two specimens. To evaluate the antiallergic effect of ginsenoside Rg5 and its metabolites, the inhibitory effect of ginsenoside Rg5 and its metabolite ginsenoside Rh3 against RBL-2H3 cell degranulation, mouse passive cutaneous anaphylaxis (PCA) reaction induced by the IgE-antigen complex, and mouse ear skin dermatitis induced by 12-O-tetradecanoilphorbol-13-acetate (TPA) were measured. Ginsenosides Rg5 and Rh3 potently inhibited degranulation of RBL-2H3 cells. These ginsenosides also inhibited mRNA expression of proinflammatory cytokines IL-6 and $TNF-{\alpha}$ in RBL-2H3 cells stimulated by IgE-antigen. Orally and intraperitoneally administered ginsenoside Rg3 and orally administered ginsenoside Rg5 to mice potently inhibited the PCA reaction induced by IgE-antigen complex. However, intraperitoneally administered ginsenoside Rg5 nearly did not inhibit the PCA reaction. These ginsenosides not only suppressed the swelling of mouse ears induced by TPA, but also inhibited mRNA expression of cyclooxygenase-2, $TNF-{\alpha}$, and IL-4 and activation of transcription factor NF-kB. These inhibitions of ginsenoside Rh3 were more potent than those of ginsenoside Rg5. These findings suggest that ginsenoside Rg5 may be metabolized in vivo to ginsenoside Rh3 by human intestinal microflora, and ginsenoside Rh3 may improve antiallergic diseases, such as rhinitis and dermatitis.

• IMMUNE NETWORK
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• v.7 no.4
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• pp.197-202
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• 2007

Background: Immunomodulators enhancing MHC-restricted antigen presentation would affect many cellular immune reactions mediated by T cells or T cell products. However, modulation of MHC-restricted antigen presentation has received little attention as a target for therapeutic immunoregulation. Here, we report that lectins isolated from mushroom Fomitella fraxinea enhance MHC-restricted exogenous antigen presentation in professional antigen presenting cells (APCs). Methods: Lectins, termed FFrL, were isolated from the carpophores of Fomitella fraxinea, and its effects on the class I and class II MHC-restricted presentation of exogenous ovalbumin (OVA) were examined in mouse dendritic cells (DCs) and mouse peritoneal macrophages. The effects of FFrL on the expression of total MHC molecules and the phagocytic activity were also examined in mouse DCs. Results: DCs cultured in the presence of FFrL overnight exhibited enhanced capacity in presenting exogenous OVA in association with class I and class II MHC molecules. FFrL increased slightly the total expression levels of both class I (H-$2K^b$) and class II (I-$A^b$) MHC molecules and the phagocytic activity of DCs. Antigen presentation-enhancing activity of FFrL was also observed in macrophages isolated from mouse peritoneum. Conclusion: Lectins isolated from the carpophores of Fomitella fraxinea increase MHC-restricted exogenous antigen presentation by enhancing intracellular processing events of phagocytosed antigens.

• The Journal of the Korean Society for Microbiology
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• v.22 no.2
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• pp.163-166
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• 1987

A new method for rosette assay is described for the detection of antigen-specific lymphocytes from BCG-infected mice using sheep erythrocytes coated with BCG antigen. The optimal concentration of BCG antigen for preparation of indicator cells and the incubation time of antigen coated erythrocytes-lymphocytes mixture were $50\;{\mu}g/ml$ and 1 h, respectively. The number of rosette-forming cells (RFC) during the course of BCG infection showed gradual increase as infection progressed and RFC was reached maximum (about 5-7% of splenic lymphocytes formed rosette) at 3 or 4 weeks after infection.

• Bulletin of the Korean Chemical Society
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• v.18 no.1
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• pp.44-50
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• 1997

A method of dual-signal generation from two different enzymes was developed and utilized to simultaneously perform dual immunoassays in a single microwell. Two enzymes selected as tracers were horseradish peroxidase (HRP) and β-galactosidase (GAL). 3, 3', 5, 5'-Tetramethylbenzidine (TMB) and chlorophenolred-β-galactopyranoside (CPRG) as chromogenic substrates for the respective enzyme were used. Although the two enzymes showed their maximum activities at distinct pH conditions (pH 5.1 for HRP and 7.5 for GAL), the enzyme reactions were able to be concurrently carried out at pH 5.75 in a dual-substrate solution without signal loss. This performance was achieved by increasing TMB concentration two-fold, introducing potassium salt as activator of GAL reaction, and extending total reaction time 50%. The signal generation method was then used for dual-enzyme immunoassays to detect antibodies with co-immobilized Hepatitis C virus antigens (core and NS5) and a Hepatitis B virus antigen (PreS(2)) in a microwell. Dose-response curves of the assays revealed cooperativity between different antigen-antibody complex formation, which suggested that dual immunoassays can only be used for qualitative screening tests unless the antigens immobilized were spatially separated.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.226.2-226.2
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• 2003

The FimH subunit of type 1-fimbriated Escherichia coli has been determined as a major cause of urinary tract infection. To produce a possible vaccine antigen against urinary tract infection, the fimH gene was genetically linked to the Itxa2b gene, which was then cloned into the pMAL -p2E expression vector. The chimaeric construction of pMALfimH/Itxa2b was transformed into Escherichia coli TB1 and its N-terminal amino acid sequence was analyzed. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.309.2-309.2
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• 2002

The FimH subunit of type l-fimbriated Escherichia coli has been determined as a major cause of urinary tract infection. To produce a possible vaccine antigen against urinary tract infection, the fimH gene was genetically coupled to the ctxa2b gene, which was then cloned into pMAL -p2E expression vector. The chimaeric construction of pMALfimH/ctxa2b was transformed into Escherichia coli TB1 and its N-terminal amino acid sequence was analyzed. (omitted)

• Journal of Life Science
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• v.6 no.2
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• pp.111-119
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• 1996

The production of interleukin-1(IL-1)and nitric oxide(NO) by cultured fibroblast cells of human nasal turbinate was revealed by biological assay respectively. The cells were incubated for various periods of time in the presence of staphyloccocal toxic shock syndrome toxin-1(TSST-1) and house dust mite(Dermatophagoides farinae, HDM), and the culture supernatants were harvested. There was a little difference in the activities of IL-1beta and the amount of NO produced by the cells when stimulated with 0.002-0.1$\mu$g/ml of TSSTO-1 and 0.02-1$\mu$g/ml of HDM. The shapes of the time course curves for the production of IL-1beta and NO by the cells were different. Groups stimulated with TSST-1 or HDM produced more IL-beta in 2 h than no exposure group(Control). A certain mixed group(TSST-1, 10ng+mite, 100 ng) continued to produce IL-1beta highly throughout the entire incubation period. The cells stimulated with TSST-1 or HDM produced more NO in 2 h and 6 h than that produced in the end of incubation(48 h). Also, the mixed groups were generally similar. There results suggest that induction of IL-1beta by a certain mixed condition(TSST-1+mite) in fibroblast cell in vivo may play a role in inflammation.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.281.2-281
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• 2000

No Abstract, See Full Text