• BMB Reports
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• v.32 no.5
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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.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2967-2971
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• 2012

Objective: To explore whether monoclonal antibodies against stathmin and the chemotherapuetic agent paclitaxel have synergenic effects in inhibiting growth and inducing apoptosis in human QG-56 cells. Methods: QG-56 cells were treated with monoclonal antibodies against stathmin or paclitaxel alone or in combination, with untreated cells used as controls. After 24, 48, 72 and 96 hours the cell growth condition was observed under an inverted microscope and inhibition was studied by MTT assay; apoptosis was analyzed by flow cytometry. Results: The populations decreased and cell shape and size changed after the various treatments. Monoclonal antibodies against stathmin and paclitaxel used alone or incombination inhibited the proliferation of QG-56 cells, especially in combination with synergism (P<0.05). Combined treatment also resulted in a significantly higher apoptosis rate than in the other groups (P<0.05). Conclusions: Monoclonal antibodies against stathmin and paclitaxel used alone or in combination can inhibit proliferation of QG-56 cells and induce apoptosis when applied together. The observed synergistic effects may have important implications for clinical application.

• BMB Reports
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• v.30 no.6
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• pp.390-396
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• 1997

A sandwich-type enzyme-linked immunosorbent assay (ELISA) for the quantification of human apolipoprotein A-I (apoA-I) was developed using monoclonal antibodies. For this assay, we used three monoclonal antibodies to trap and detect apo A-I. HDAI16 and HDA15 monoclonal antibodies were used for trapping apoA-I and HDAI8 monoclonal antibody was for detecting apoA-I. These three monoclonal antibodies were produced by immunizing mice with high density lipoprotein (HDL) isolated from human plasma. By immunoblot analysis, these three monoclonal antibodies were specific to apoA-I and showed no cross-reactivities with other plasma proteins. The results of competition assays for epitope cross-reactivity test also verified that these monoclonal antibodies identified separate and distinct epitopes on HDL and apoA-I. Affinity constants of monoclonal antibodies were measured by ELISA. Their association constants ranged from $10^7$ to $10^8$ $M^{-1}$. For this assay, pure apoA-I was isolated by affinity chromatography using monoclonal antibodies. In this sandwich assay, the amount of HRP-labeled HDAI8 bound to apoA-I trapped by HDAI16 and HDAI5 was proportional to apoA-I concentration in the range of 0 to 500ng/ml. ApoA-I concentration in plasma was calculated from the linear regression equation of standard curve. The precision and reliability of the assays are reflected in the low intra-and interassay coefficients of variation that averaged 3.25% and 4.30%, respectively. This assay is sensitive, simple, reproducible, convenient in incubation interval, and does not use radioisotope: thus it can be widely applied in clinical laboratories.

• 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.

• Journal of Periodontal and Implant Science
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• v.37 no.1
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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.

• The Korean Journal of Zoology
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• v.31 no.4
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• pp.300-308
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• 1988

Human placental alkaline phosphatase (PLAP), one of the oncofetal antigen was purified from placentas through the procedures including butanol extraction, concanavalin A-Sephar-ose, DEAE-cellulose and Sephadex G-200 gel chromatography. Monoclonal antibodies (fibs) against human PMP were produced by hybridizing SP 210-Ag 14 mouse myeloma cells with spleen ceils of Balblc mice immunized with PLAP. Six stable monoclones uvere obtained by cloning tuvice in serial dilutions, and the monoclonal speclfidty of these MAbs was confirmed by biochemical and immunonogical criteria. Tumor marker의 하나인 태반형 alkaline phosphatase(PLAP)에 대한 단일 클론항체의 생산과 분석을 위하여, 태반조직을 재료로 butanol 추출법 및 concanavaline A-Sepharose, DEAE-cellulose, Sephadex G-200 gel 크로마토그라피법에 의하여 PLAP를 순수 분리하였다. 이를 항원으로 하여 하이브리도마 방법에 의해 항-PLAP 단일 클론항체를 생산 분비하는 안정된 6클론세포를 얻었으며 생화학적 및 면역학적 분석방법으로 이들의 단일 클론성을 확인하였다.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.7-13
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• 2001

Currently 18 monoclonal antibodies were approved by FDA for inj ection into humans for therapeutic or diagnostic purpose. And 146 clinical trials are under way to evaluate the efficacy of monoclonal antibodies as anti-cancer agents, which comprise 9 % of clinical trials in cancer therapy field. When considering a lot of disappointment and worries existed in this field during the past 15 years, this boom could be called as resurrection. Antibodies have several merits over small molecule drug. First of all it is easier and faster in development, as proper immunization of the target proteins usually raises good antibody response. The side effects of antibodies are more likely to be checked out in immunohistomchemical staining of whole human tissues. Antibody has better pharmacokinetics, which means a longer half-life. And it is non-toxic as it is purely a "natural drug. Vast array of methods was developed to get the recombinant antibodies to be used as drug. The mice with human immunoglobulin genes were generated. Fully human antibodies can be developed in fast and easy way from these mice through immunization. These mice could make even human monoclonal antibodies against any human antigen like albumin. The concept of combinatorial library was also actively adopted for this purpose. Specific antibodies can be screened out from phage, mRNA, ribosomal library displaying recombinant antibodies like single chain Fvs or Fabs. Then the coding genes of these specific antibodies are obtained from the selected protein-gene units, and used for industrial scale production. Both $na\ddot{i}ve$ and immunized libraries are proved to be effective for this purpose. In post-map arena, antibodies are receiving another spotlight as molecular probes against numerous targets screened out from functional genomics or proteomics. Actually many of these antibodies used for this purpose are already human ones. Through alliance of these two actively growing research areas, antibody would play a central role in target discovery and drug development.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.565-578
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• 2008

Purpose: Porphyromonas gingivalis(P. gingivalis) heat shock protein (HSP)60 may play a role in the immunopathogenesis of periodontitis as well as atherosclerosis by modulating autoimmune reaction due to its high level of sequence homology between bacteria and human counterpart. The purpose of this study was to identify immunodomiant epitope of P. gingivalis HSP60 that is reactive exclusively to the homologous bacteria without reacting with human HSP. Materials and methods: The present study was performed to identify the peptide specifically recognized by anti-P. gingivalis HSP60 monoclonal antibodies mono-reactive to P. gingivalis HSP60. Results: Four different hybridomas were cloned producing monoclonal IgG antibodies exclusively to P. gingivalis HSP60. Thirty seven synthetic peptides (20-mer with 5-amino acid overlapping) were synthesized. All of these peptide were subject to SDS-PAGE for immunblot analysis. One peptide (TVPGGGTTYIRAIAALEGLK) and the other peptide (TLVVNRLRGSLKICAVKAPG) were recognized by all and one of the four monoclonal antibodies, respectively, that reacted solely with P. gingivalis HSP60. Immunohistochemistry to identify the localization of the HSP60 in the diseased gingival tissues revealed that all of the four monoclonal antibodies were highly reacted with the diseased gingival tissue than normal gingival tissue. Conclusion: The P. gingivalis HSP60 peptides (TVPGGGTTYIRAIAALEGLK and TLVVNRLRGSLKICAVKAPG, respectively) are positively involved in the immunopathologic process of periodontal disease. The peptide may potentially be 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.

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.971-980
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• 1996

The soluble transferrin receptor(TfR) in human serum has been shown recently to be a truncated form of intact membrane bound receptor containing most of the extracellular domain. We purfied the transferin-free TfR from human serum by immounoaffinity chromatography which produced the single protein identity in high resolution gel chormatography. The monoclonal antibodies(MAb) against purifed serum TfR were produced by fusion of spleen cells o fimmunized Balb/c mice and SP2 cells. Ten hybrids producing MAb specific for serum TfR were identifed and determine their iostypes. A immunoraddiometric assay (IRMA) for serum TfR was established using two monoclonal IgG1 antibodies as the coating and indicator antibodies on the bosis of their suitability in sandwich IRMA of serum TfR. The mean serum TfR levels in the 15 normal male, 15 normal female, and 19 iron-deficient subjects were 5.4$\pm$0.98, 4.6$\pm$0/76, and 18.0$\pm$12.8mg/1, respectively, and the difference in mean values between normal and iron deficient subjects was significant(p=0.0005). There existed the inverse logarithmic relationship(r=-0.9336, p<0.0001) between the serum TfR and ferritin levels.

• Molecules and Cells
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• v.20 no.1
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• pp.17-29
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• 2005

Therapeutic antibodies represent one of the fastest growing areas of the pharmaceutical industry. There are currently 19 monoclonal antibodies in the market that have been approved by the FDA and over 150 in clinical developments. Driven by innovation and technological developments, therapeutic antibodies are the second largest biopharmaceutical product category after vaccines. Antibodies have been engineered by a variety of methods to suit a particular therapeutic use. This review describes the structural and functional characteristics of antibody and the antibody engineering for the generation and optimization of therapeutic antibodies.