• BMB Reports
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• 제32권5호
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• pp.474-479
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• 1999

Using a hybridoma technique, spleen cells of Balb/c mice immunized with human chorionic gonadotropin (hCG) were fused with NS-1 mouse myeloma cells. Two hybrid cell lines, clones KS-8 and KS-19, secreting monoclonal antibodies to hCG, were isolated. KS-8 and KS-19 belong to the immunoglobulin $G_1$ subclass. With the aid of a double-antibody radioimmunoassay, it was established that the KS-8 monoclonal antibody recognizes an immunodeterminant of the $\beta$-subunit of hCG, whereas the KS-19 monoclonal antibody recognizes an epitope present on the $\alpha$-subunit of hCG. The KS-8 monoclonal antibody specifically reacts with human chorionic gonadotropin and shows cross-reactivity of less than 0.3% to other related human glycoprotein hormones. On the other hand, using a hemagglutination test based on antibody-induced agglutination of sheep red blood cells coated with hCG, It was shown that only the KS-19 monoclonal antibody was capable of inducing a positive reaction, although both monoclonal antibodies had similar binding capacity to the coated cells. The results from the dual screening procedures demonstrate that KS-8 and KS-19 monoclonal antibodies show high sensitivity in two different assays, and are hence useful for the qualitative and quantitative determination of hCG by both radioimmunoassay and hemagglutination inhibition tests.

• Biomolecules & Therapeutics
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• 제5권4호
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• pp.344-350
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• 1997

The purpose of the present study was to produce and characterize a monoclonal antibody against human ${\beta}_2$-adrenergic receptor. Male BALB/c mice were immunized with glutathione S-transferase (GST) fusion protein of the C-terminal portion of the human ${\beta}_2$-adrenergic receptor which was expressed in E.Coli. The immunized splenocytes were fused with myeloma SP2/0-Agl4 cells. The resulting hybridomas were screened for the production of a monoclonal antibody which can recognize human ${\beta}_2$-adrenergic receptor, and then subcloned by limiting dilution. The resulting monoclonal antibody was named as mAb$\beta$CO2. The mono-clonal antibody $\beta$CO2 was determined as IgM subtype and then purified by anti-mouse IgM-agarose affinity chromatography. The results of ELISA, Western blot, and immunocytochemistry showed that mAb$\beta$CO2 recognized human ${\beta}_2$-adrenergic receptor in the ${\beta}_2$-adrenergic receptor-GST fusion protein and human spider-moid carcinoma cell line A431 with highly specific immunoreactivity, The monoclonal antibody $\beta$CO2 may provide useful tools for the study of the $\beta$-adrenergic receptor of human and other species including rats.

• Journal of Periodontal and Implant Science
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• 제37권1호
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• pp.11-21
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• 2007

Heat shock protein (HSP) is one of cellular protein commonly present in major periodontopathogenic bacteria as well as mammalian cells. The protein may play a role in the immunopathogenesis by modulating autoimmune reaction due to its high level of sequence homology between bacteria and human counterpart. Hence, identifying immunodomiant epitope of bacteria HSP that is cross-reactive to periodontopathogenic bacteria with a specificity to human HSP may comprise a critical strategy for development of a periodontal vaccine. The present study was performed to establish clones producing monoclonal antibody reactive to Porphyromonas gingivalis (p. gingivalis) HSP with a specificity to human HSP. 4 different hybridomas were cloned producing monoclonal IgG antibodies to P, gingivalis HSP and evaluated for their reactivity and specificity to other periodontopathogenic bacteria as well as to human HSP. These four monoclonal antibodies reacted with p. gingivalis HSP only with specificities to other bacteria tested and human HSP as well. The antigenic epitopes producing the 4 monoclonal antibody may be potentially developed as vaccine candidates. Further investigations are under way to identify more clones producing monoclonal antibodies reactive to P, gingivalis HSP and to other periodontopathogenic bacteria as well, while maintaining specificities to human counterpart.

• 대한세포병리학회지
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• 제7권2호
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• pp.134-137
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• 1996

Monoclonal antibody(TCM-9) against human thyroid cancers have been studied by screening with human thyroid cancers, normal and benign thyroid tissue, and normal human serum protein. A monoclonal antibody(TCM-9) that is known to have strong specificity for human thyroid cancer but not for Graves' disease, adenoma or normal thyroid does not bind to native or mature human thyroglobulin(Tg). We used to TCM-9 antibody by immunohistochemical staining on 5 follicular cancer, 2 follicular adenoma, 1 follicular neoplasm with suspicious invasion, 2 papillary cancer to ascertain being of help in differentiation between follicular carcinoma and adenoma. Reactivity of TCM-9 was observed in follicular carcinoma and papillary carcinoma but not observed in follicular adenoma. Thus TCM-9 is a novel monoclonal antibody against the thyroid cancer.

• Journal of Microbiology and Biotechnology
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• 제28권12호
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• pp.2113-2120
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• 2018

Cross-reactive material 197 ($CRM_{197}$) is a non-toxic mutant of diphtheria toxin containing a single amino acid substitution of glycine 52 with glutamic acid. $CRM_{197}$ has been used as a carrier protein for poorly immunogenic polysaccharide antigens to improve immune responses. In this study, to develop a sandwich ELISA that can detect $CRM_{197}$ and $CRM_{197}$ conjugate vaccines, we generated a human anti-$CRM_{197}$ monoclonal antibody (mAb) 3F9 using a phage-displayed human synthetic Fab library and produced mouse anti-$CRM_{197}$ polyclonal antibody. The affinity ($K_D$) of 3F9 for $CRM_{197}$ was 3.55 nM, based on Bio-Layer interferometry, and it bound specifically to the B fragment of $CRM_{197}$. The sandwich ELISA was carried out using 3F9 as a capture antibody and the mouse polyclonal antibody as a detection antibody. The detection limit of the sandwich ELISA was <1 ng/ml $CRM_{197}$. In addition, the 3F9 antibody bound to the $CRM_{197}$-polysaccharide conjugates tested in a dose-dependent manner. This ELISA system will be useful for the quantification and characterization of $CRM_{197}$ and $CRM_{197}$ conjugate vaccines. To our knowledge, this study is the first to generate a human monoclonal antibody against $CRM_{197}$ and to develop a sandwich ELISA for $CRM_{197}$ conjugate vaccines.

• IMMUNE NETWORK
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• 제2권3호
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• pp.175-181
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• 2002

Background: S100A6 is a calcium-binding protein overexpressed in several tumor cell lines including melanoma with high metastatic activity and involved in various cellular processes such as cell division and differentiation. To detect S100A6 protein in patient' samples (ex, blood or tissue), it is essential to produce a monoclonal antibody specific to the protein. Methods: First, cDNA coding for ORF region of human S100A6 gene was amplified and cloned into the expression vector for GST fusion protein. We have produced recombinant S100A6 protein and subsequently, monoclonal antibodies to the protein. The specificity of anti-S100A6 monoclonal antibody was confirmed using recombinant S100A recombinant proteins of other S100A family (GST-S100A1, GST-S100A2 and GST-S100A4) and the cell lysates of several human cell lines. Also, to identify the specific recognition site of the monoclonal antibody, we have performed the immunoblot analysis with serially deleted S100A6 recombinant proteins. Results: GST-S100A6 recombinant protein was induced and purified. And then S100A6 protein excluding GST protein was obtained and monoclonal antibody to the protein was produced. Monoclonal antibody (K02C12-1; patent number, 330311) has no cross-reaction to several other S100 family proteins. It appears that anti-S100A6 monoclonal antibody reacts with the region containing the amino acid sequence from 46 to 61 of S100A6 protein. Conclusion: These data suggest that anti-S100A6 monoclonal antibody produced can be very useful in development of diagnostic system for S100A6 protein.

• Journal of Microbiology
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• 제45권6호
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• pp.547-552
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• 2007

Previously, we generated monoclonal antibodies (MAbs) that bound to the surface of human embryonic stem cells (hESCs) in an attempt to discover new hESC-specific surface markers. In this study, MAb 47-235 (IgG1, ${\kappa}$) was selected for further characterization. The MAb bound to the surface of undifferentiated hESCs but did not bind to mouse ESCs or mouse embryonic fibroblast cells in flow cytometric analysis. The antibody immunoprecipitated a 47 kDa protein from the lysates of cell surface-biotinylated hESCs. Identification of the protein by quadrupole time of flight tandem mass spectrometry revealed that 47-235 binds to Ag 243-5 protein of Mycoplasma arginini. BM-Cyclin treatment of the hESCs that reacted with 47-235 resulted in loss of mycoplasma DNA and the reactivity to 47-235. Nevertheless, the hESCs that were reactive to 47-235 maintained self-renewal and pluripotency and thus could be differentiated into three embryonic germ layers.

• Journal of Microbiology
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• 제45권6호
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• pp.572-577
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• 2007

To enhance therapeutic potential of murine monoclonal antibody, humanization by CDR grafting is usually used to reduce immunogenic mouse residues. Most humanized antibodies still have mouse residues critical for antigen binding, but the mouse residues may evoke immune responses in humans. Previously, we constructed a new humanized version (AKA) of mouse CC49 antibody specific for tumor-associated glycoprotein, TAG-72. In this study, to select a completely human antibody light chain against TAG-72, guided selection strategy using phage display was used. The heavy chain variable region (VH) of AKA was used to guide the selection of a human TAG-72-specific light chain variable region (VL) from a human VL repertoire constructed from human PBL. Most of the selected VLs were identified to be originated from the members of the human germline VK1 family, whereas the VL of AKA is more homologous to the VK4 family. Competition binding assay of the selected Fabs with mouse CC49 suggested that the epitopes of the Fabs overlap with that of CC49. In addition, they showed better antigen-binding affinity compared to parental AKA. The selected human VLs may be used to guide the selection of human VHs to get completely human anti-TAG72 antibody.

• 대한의생명과학회지
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• 제5권1호
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• pp.1-10
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• 1999

본 연구에서는 혈장이나 양수에 있는 $\alpha$-fetoprotein (AFP)을 인식 할 수 있는 모노클로날 항체를 제조하고, 모노클로날 항체를 이용한 효소면역분석법을 개발하고자 하였다. 양수로부터 얻은 AFP를 쥐에 주사한 후 비장을 분리하여 종양세포 (Sp2/O-Ag-14)와 융합하였고, 하이브리도마 기술을 이용하여 모노클로날 항체를 제조하였다. 모노클로날 항체를 클로닝하였으며, 생성된 항체를 MabF22로 명명하였고, IgG1 중사슬과 k 경사슬의 isotype을 나타냈다. 또한 immunoblotting 방법과 ELISA로 특이도를 조사한 결과 모노클로날 항체는 AFP와만 반응하였고, 결합 친화상수는 0.8$\times$$10^{-10}$M이었다. 두 종류의 효소면역분석법 -경쟁적 또는 비경쟁적 분석 -을 이용하여 항체의 효용성을 조사하였으며, 두 방법 모두 AFP와 농도에 비례하여 반응하였다. 따라서 본 연구에서 생산된 모노클로날 항체는 연구목적으로 뿐만 아니라 AFP 농도를 측정하기 위한 면역진단시약의 개발에도 유용할 것으로 생각된다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.95-95
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• 1997

Among the various receptor molecules discovered so far the ${\beta}$2-adrenergic receptors have been regarded as excellent model systems for the so called 7 transmembrane helix receptor and have been the focus of extensive studies. For the analysis of receptor structure and function a monoclonal antibody plays a crucial role, thus providing useful tools for the study of receptor. However, because of the minute quantity of receptor molecules which could be obtained from natural sources, the generation of specific monoclonal antibody against receptor molecules from the purified receptors has been regarded as virtually impractical in consideration of cost and experimental times. The purpose of the present study was to generate and characterize a monoclonal antibody against human ${\beta}$2-adrenergic receptor. For the production of antibody, C-terminal regions of the human ${\beta}$2-adrenergic receptor was produced as a fusion protein with Glutathion S-transferase (GST) in E. Coli. The expression of the fusion protein was identified by SDS-PAGE and Western blot using monoclonal anti-GST antibody. The fusion protein was purified to an apparent homogeniety by affinity chromatography with Glutathion Sepharose CL-4B and used as an antigen for the immunization of BALB/C mice. The Production of monoclonal antibody was achieved by fusion of the immunized spleen cells and SP/2-0 myeloma cells. Positive hybridomas were screened by ELISA and were cloned by two consecutive rounds of limiting dilution. The monoclonal antibody produced in this study (mAb${\beta}$C02) was IgM type and purified by immunoaffinity chromatography using anti-mouse IgM agarose as an affinity matrix. MAb${\beta}$C02 showed strong and specific immunoreactivity against both the fusion protein and human ${\beta}$2-adrenergic receptor in ELISA and Western blot. The molecular weight of immunoreactive band was 64 kDa and exactly coincided with the previously reported molecular weight of ${\beta}$2-adrenergic recepters. The results of the present study suggest that mAb${\beta}$C02 may be used for the study of receptor function and regulation in normal or nonphysiological status.