• YAKHAK HOEJI
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• v.47 no.3
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• pp.190-194
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• 2003

As previously reported, an immunoglobulin M (IgM) monoclonal antibody (MAb) B6.1, specific for a cell wall B-l,2-mannotriose, was protective against vaginal infection due to Candida albicans when mice were treated with the antibody. In this study, the role of neutrophil was examined in the protective effect of MAb B6.1 against vaginal infection. To deplete neutrophils, mice were given intravenously rat anti-mouse neutrophile MAb RB6-8C5 prior to intraperitoneal administration of MAb B6.1 to these mice. The mice were examined for antibody in their reproductive tract. By an ELISA, MAb B6.1 was found in the vaginal homogenates, but no antibody was detected in vaginal lavage materials. The neutropenia was induced by a single dose of the anti-neutrophil antibody, but lymphocytes were also partially depleted. The protective effect of MAb B6.1 was decreased when mice pretreated with MAb RB6-8C5 were given the anti-Candida antibody before challenge with C. albicans yeast cells intravaginally. These results show that neutrophils are involved in the MAb B6.1 protection against Candida vaginal infection.

• Molecules and Cells
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• v.39 no.6
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• pp.460-467
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• 2016

Bacteriophytochromes are phytochrome-like light-sensing photoreceptors that use biliverdin as a chromophore. To study the biochemical properties of the Deinococcus radiodurans bacteriophytochrome (DrBphP) protein, two anti-DrBphP mouse monoclonal antibodies (2B8 and 3H7) were generated. Their specific epitopes were identified in our previous report. We present here fine epitope mapping of these two antibodies by using truncation and substitution of original epitope sequences in order to identify minimized epitope peptides. The previously reported original epitope sequences for 2B8 and 3H7 were truncated from both sides. Our analysis showed that the minimal peptide sequence lengths for 2B8 and 3H7 antibodies were nine amino acids (RDPLPFFPP) and six amino acids (PGEIEE), respectively. We further characterized these peptides in order to investigate their reactivity after single deletion and single substitution of the original peptides. We found that single-substituted 2B8 epitope (RDPLPAFPP) and dual-substituted 3H7 epitope (PGEIAD) showed significantly increased reactivity. These two antibodies with high reactivity for the short modified peptide sequences are valueble for developing new peptide tags for protein research.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1498-1504
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• 2005

Competitive direct ELISA was developed to detect gentamicin residues. Mice immunized with gentamicin-keyhole limpet hemocyanin (KLH) conjugate developed good antiserum titers, which gradually increased with booster injections, indicating immunization was successfully processed. Monoclonal antibody against gentamicin was prepared using hybridoma cells cloned by limit dilution of fused cells. IgG was purified from ascites fluid of hybridoma cell-injected mice through ammonium sulfate precipitation and Sephadex G-25 gel filtration. After the gel filtration, fractions of high antibody titer were further purified through affinity chromatography on protein A/G column. Monoclonal antibody against gentamicin was confirmed as IgG1, which has kappa light chain. Cross-reactivities ($CR_{50}$) of gentamicin monoclonal antibody to other aminoglycosides (kanamycin, neomycin, and streptomycin) were less than 0.005%, indicating the monoclonal antibody was highly specific for gentamicin. Standard curve constructed through competitive direct ELISA showed measurement range (from 80 to 20% of B/$B_0$ ratio) of gentamicin was between 1 and 40 ng/ml, and 50% of B/$B_0$ ratio was about 4 ng/ml. The gentamicin concentration rapidly increased to 1,300 ng/ml after the intramuscular administration up to 2 h, then sharply decreased to less than 300 ng/ml after 4 h of withdrawal, during which the elimination half-life ($t_{1/2}$) of gentamicin in the rabbit plasma was estimated to be 1.8 h. Competitive direct ELISA method developed in this study using the prepared monoclonal antibody is highly sensitive for gentamicin, and could be useful for detecting gentamicin residues in plasma of live animals.

• BMB Reports
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• v.28 no.4
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• pp.353-358
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• 1995

Epitope tagging is the process of fusing a set of amino acid residues that are recognized as an antigenic determinant to a protein of interest. Tagging a protein with an epitope facilitates various immunochemical analyses of the tagged protein with a specific monoclonal antibody. The monoclonal antibody H8 has subtype specificity for an epitope derived from the preS2 region of hepatitis B virus surface antigen. Previous studies on serial deletions of the preS2 region indicated that the preS2 epitope was located in amino acid residues 130~142. To test whether the amino acid sequence in this interval is sufficient to confer on proteins the antigenicity recognizable by the antibody H8, the set of amino acid residues in the interval was tagged to the amino terminal of ${\beta}$-galactosidase and to the carboxyl terminal of the truncated $p56^{lck}$ fragment. The tagged ${\beta}$-galactosidase, expressed in Escherichia coli, maintained the enzymatic activity and was immunoprecipitated efficiently with H8. The tagged $p56^{lck}$ fragment, synthesized in an in vitro translation system, was also immunoprecipitated specifically with H8. These results demonstrate that the amino acid sequence of the preS2 region can be used efficiently for the epitope tagging approach.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.625-635
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• 2004

Trichnuris suis does not excrete eggs during larval stage as well as in particular adult stage, It is impossible to diagnose by use of fecal examination method in those periods. Therefore, serological diagnostic method can be very useful for those stages. In order to produce monoclonal antibody, specific somatic and secretory-excretory (SE) antigens of T. suis were identified and analyzed by SDS-PAGE and Western blot. Monoclonal antibody-producing hybridoma cells were cloned, which were made of popliteal lymph node of BALB/c mice immunized with a 45 kDa somatic antigen of T. suis. Five clones (1B9, 2C4, n2C5, 2D7 and 2D8) showing strong responses to T. suis antigens were selected and the isotype identified. All monoclonal antibodies were IgG1 isotype and the light chains were k chain. Established monoclonal antibodies reacted specifically to somatic and SE antigens of T. suis and did not cross-reacted to antigens of ascaris suum, trichuris vulpis, or Trichinella spiralis. The sensitivity of somatic and SE antigens against these monoclonal antibodies were significant (p<0.01) associated with those of positive and negative sera.

• YAKHAK HOEJI
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• v.31 no.5
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• pp.253-265
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• 1987

To develop hybridomas secreting monoclonal antibodies to be used as unlimited sources of reagents indispensable for the diagnosis and treatement of leukemic malignancy, a monoclonal antibody was generated to human pre-T leukemia cells (Jurkat). Hybridomas were produced against Jurkat cell line by fusing spleen cells from hyperimmunized mice with murine plasmacytoma cells (P3$\times$63Ag8. V653). One monoclonal antibody derived from this fusion, designated DMJ-2 was reactive with T-cell lines (Jurkat, Molt-4 and RPMI-8402) and normal peripheral E-rosette forming T cells, but unreactive with B-cell lines (Daudi, Nalm-6) and non-T, non-B cell line (K562). Conclusively DMJ-2 reactive with mature and immature T-lineage lymphoid cells.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.118-125
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• 2003

Background: Disialoganglioside GD2 is a tumor-associated antigen that is overexpressed on tumor cells of neuroectodermal origin, such as melanoma and neuroblastoma. Anti-idiotypic antibodies that mimic GD2 may induce more effective immune responses than GD2 antigen itself, because they are protein antigens and are known to be able to break immune tolerance. In this study, to explore the potential of anti-idiotypic antibodies as tumor vaccines, the ability of anti-idiotypic antibodies (Ab2) to induce anti-anti-idiotypic antibodies (Ab3) that bind to the original antigen GD2 was investigated. Methods: Six monoclonal anti-idiotypic antibodies (1A8, 1G5, 2B6, 3A4, 3D6, 3H9) to monoclonal antibody M2058, which is a monoclonal antibody to GD2, were produced in mice. Three (1A8, 3A4, 3H9) of them were selected based on their ability to inhibit the binding of Ab1 to D142.34 (murine melanoma cell expressing GD2). These 3 different Ab2 were injected into rabbits, and rabbit Ab3 induced by each of them were characterized. Results: Ab3-containing sera from two rabbits immunized with 1A8, 3A4, or 3H9 bound significantly (P<0.05) to D142.34 but not to B78.96 (GD2-negative cell), and bound significantly (P<0.05) to isolated GD2 but not to GD1a. Ab3-containing sera from two rabbits immunized with 3A4 or 3H9 inhibited significantly (P<0.05) the binding of Ab1 M2058 to D142.34, and inhibited significantly (P<0.05) the binding of Ab1 M2058 to the Ab2. Conclusion: These results suggest that anti-idiotypic antibodies 3A4 and 3H9 have a potential to be used as vaccines against tumors expressing GD2 by inducing GD2-specific antibodies (Ab3).

• The Korean Journal of Zoology
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• v.35 no.1
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• pp.1-7
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• 1992

Seven monoclonal antibodies were produced by fusing splenocytes from Balb/C mouse immunized with partially purified human interferon-a (HUIFN-a) with NSO plasmacytoma cells. aery were identified as five IgG class (432.22: IgG2b/n, 460.52: IgG2b/a , 548.46: IgG2a/n , 573.10: IgG2b/h , 625.12: IgG2b/n ), one IgA class (460.50: IgA/n ) and one IsM class (465.27: IgA/n ), and all of them revealed highly sensitive to HUIFN- a IgG class monoclonal antibodies have pts ranged from 8.2 to 8.6. Ascites fluids produced from primed Balb/c mice and were purified through column chromatography. The cytopathic effect (CPE) inhibition assay to examine neutralization of HuIFU-a by IgG class monoclonal antibodies, gave that MAbs 460.52, 548.46, 573.10 can neutralize HUIFU- a arith varying degrees except 432.22. Therefore, it is deduced that these various monoclonal antibodies may recognize the distinct epitopes on HUIFN-a.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.6-12
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• 1990

The preS2 wequence of an adr hepatitis B virus was cloned and expressed in Escherichia coli as a $\beta$-galactosidase fusion polypeptide. Recombinant preS2 product interacted with the preS2-specific monoclonal antibody H8 which was induced by surface antigen particles isolated from a Korean gepatitis patient. The H8 showed only a minor cross-reactivity with recombinant preS2 product of adw2 subtype. Determination of nucleotide sequence of the adr preS2 revealed that twelve amino acid residue substitutions between adr and adw2 subtype sequences. The antigenic determinant to H8 must include some of these differences.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1376-1383
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• 2018

The hepatitis B virus (HBV) envelope contains small (S), middle (M), and large (L) proteins. PreS1 of the L protein contains a receptor-binding motif crucial for HBV infection. This motif is highly conserved among 10 HBV genotypes (A-J), making it a potential target for the prevention of HBV infection. In this study, we successfully generated a neutralizing human monoclonal antibody (mAb), 1A8 (IgG1), that recognizes the receptor-binding motif of preS1 using a phage-displayed human synthetic Fab library. Analysis of the antigen-binding activity of 1A8 for different genotypes indicated that it can specifically bind to the preS1 of major HBV genotypes (A-D). Based on Bio-Layer interferometry, the affinity ($K_D$) of 1A8 for the preS1 of genotype C was 3.55 nM. 1A8 immunoprecipitated the hepatitis B virions of genotypes C and D. In an in vitro neutralization assay using HepG2 cells overexpressing the cellular receptor sodium taurocholate cotransporting polypeptide, 1A8 effectively neutralized HBV infection with genotype D. Taken together, the results suggest that 1A8 may neutralize the four HBV genotypes. Considering that genotypes A-D are most prevalent, 1A8 may be a neutralizing human mAb with promising potential in the prevention and treatment of HBV infection.