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

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권6호
• /
• pp.856-865
• /
• 2007

Caveolin-1 of the caveolin family of proteins regulates mammary gland development and has been shown to play a contradictory role in breast tumor progression. A specific anti-Caveolin-1 antibody will be useful for functional study of Caveolin-1 in different tissues. In this study, we generated a rabbit polyclonal antibody that specifically recognizes the N-terminal amino acids 50-65 of Caveolin-1. This polyclonal antibody specifically reacted with Caveolin-1 extracted from cells of different species, including human epithelial A431 cells, goat primary mammary epithelial cells and mice fibroblast NIH 3T3 cells, by Western blotting. Endogenous Caveolin-1 protein expressing in cells and normal human tissues was detected by this polyclonal antibody using immunocytofluorescent and immunohistochemical staining, respectively. Furthermore, an apparent decrease in Caveolin-1 expression in tumorous breast and colon tissues was detected by this polyclonal antibody. In conclusion, we have identified amino acids 50-65 of Caveolin-1, which contains an epitope that is specific to Caveolin-1 and is conserved in the human, goat and mouse. In future, this anti-Caveolin-1 antibody can be used to examine the progression of breast and colon cancers and to study functions of Caveolin-1 in human, goat and mouse cells.

• 대한수의학회지
• /
• 제38권3호
• /
• pp.581-588
• /
• 1998

Eight monoclonal antibodies(MAbs) against bovine coronavirus(BCV) were produced and characterized. Three MAbs(1G9, 4H12, 5C1) specific to the S glycoprotein and two HE glycoprotein-specific MAbs(2A5, 5G4) were found to neutralize the BCV in fluorescence focus neutralization(FFN) test. Two HE-specific MAbs from the neutralizing MAbs inhibited the hemagglutinating activity of the BCV. None of the N protein-specific MAbs(1C1, 5A12, 6H1) neutralized the virus infectivity. Bovine coronavirus and mouse hepatitis virus, which belong to group II coronaviruses, were differentiated from other groups of coronaviruses(porcine transmissible gastroenteritis virus, porcine epidemic diarrhea virus, canine coronavirus) by all MAbs in fluorescence antibody test(FA), but not in FFN test.

• BMB Reports
• /
• 제48권9호
• /
• pp.489-494
• /
• 2015

The in vitro antibody discovery technologies revolutionized the generation of target-specific antibodies that traditionally relied on the humoral response of immunized animals. An antibody library, a large collection of diverse, pre-constructed antibodies, can be rapidly screened using in vitro display technologies such as phage display. One of the keys to successful in vitro antibody discovery is the quality of the library diversity. Antibody diversity can be obtained either from natural B-cell sources or by the synthetic methods that combinatorially generate random nucleotide sequences. While the functionality of a natural antibody library depends largely upon the library size, various other factors can affect the quality of a synthetic antibody library, making the design and construction of synthetic antibody libraries complicated and challenging. In this review, we present various library designs and diversification methods for synthetic antibody library. From simple degenerate oligonucleotide synthesis to trinucleotide synthesis to physicochemically optimized library design, the synthetic approach is evolving beyond the simple emulation of natural antibodies, into a highly sophisticated method that is capable of producing high quality antibodies suitable for therapeutic, diagnostic, and other demanding applications. [BMB Reports 2015; 48(9): 489-494]

• BMB Reports
• /
• 제33권1호
• /
• pp.92-95
• /
• 2000

The HIV-1 p24(202-221) sequence ETINNEEEWDRVHPV HAGP contains a B-cell epitope with the earliest immune response and the highest antibody titer against anti-mouse sera obtained by immunization with p24 antigens. A novel mouse monoclonal antibody (mAb) was generated against the immunodominant B-cell epitope of the HIV-1 p24 capsid protein, p24(202-221). BALB/c mice were immunized with the four branched multiple antigenic peptide (MAP) containing the HIV-1p24(202-221) sequence, and antibody-secreting hybridoma were produced by fusion of mouse splenocytes with P3X63Ag8.653, mouse myeloma cells. One clone which produced the antigen-specific mAb named KI-24 (Isotype IgG1, light chain: ${\kappa}$) was identified. mAb KI-24 was highly specific for both the p24(202-221) and p24 proteins when analyzed by ELISA and Western blotting. Since p24(202-221) also contains a cytotoxic T-lymphocyte epitope, this specfic peptide epitope and the monoclonal antibody with specific reactivity against the p24 protein and p24(202-221) can be used in peptide vaccine development and p24 antigen detection from HIV patients.

• BMB Reports
• /
• 제31권1호
• /
• pp.58-63
• /
• 1998

In this study, a mouse monoclonal antibody (mAb) against gp41(584-618), the immunodominant epitope protein, was generated. For this purpose, BALB/c mice were immunized with double branched multiple antigenic peptides derived from the HIV-1 gp41(584-618) sequence, and antibody-secreting hybridoma were produced by fusion of mice splenocytes with SP2/0 myeloma cells. One clone producing an antigen specific mAb, termed KI-41(isotype IgG1) was identified, whose specific reactivity against gp41(584-618) could be confirmed by ELISA and Western blot analysis. Epitope mapping revealed the recognition site of the mAb KI-41 to be located around the sequence RILAVERYLKDQQLLG, which comprises the N-terminal region within the immunized gp41(584-618) peptied. Since this mAb recognizes this specific epitope within the HIV-1 gp41 without any cross-reactivity to other immunodominant regions in the HIV-2 gp35, KI-41 will provide some alternative possibilities in further applications such as the development of indirect or competitive ELISA for specific antibody detection in HIV-1 infection or for other basic researches regarding the role and function of HIV-1 gp41.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제5권2호
• /
• pp.79-83
• /
• 2000

A han transfers her serum immunoglobulin G to the agg (IgY) and gives immunity to her offspring. Therefore, The hen agg can be an effective supplier of a large amount of antigen specific antibody that accumulates in the egg yolk. Antigen specific antibody has been widely used for immunological analysis in the field of diagnosis as well as pure scientific research. The production and separation technology of IgY is demonstrated in the present study.

• Parasites, Hosts and Diseases
• /
• 제38권3호
• /
• pp.191-194
• /
• 2000

Genus specific antigenicity of the 10 kDa protein in cyst fluid (CF) of Taenia solium metacestodes was demonstrated by comparative immunoblot analysis. When CFs from taeniid metacestodes of T. saginata, T. solium, T. taeniaeformis and T. crassiceps were probed with specific monoclonal antibody (mAb) raised against 150 kDa protein of T. solium metacestodes, specific antibody reactions were observed in 7 and 10 kDa proteins of T. solium and in 7/8 kDa of T. saginata, T. taeniaeformis and T. crasiceps. The mAb did not react with any protein in hydatid fluid of Echinococcus granulosus and E. multilocularis. This result revealed that the 10 kDa peptide of T. solium metacestodes and its equivalent proteins of different Taenia metacestodes are genus specific antigens that are shared among different Taenia species.

• Journal of Microbiology and Biotechnology
• /
• 제20권8호
• /
• pp.1179-1184
• /
• 2010

We report the generation of the first monoclonal antibody that specifically binds to the polysaccharide chitosan. Mice were immunized with a mixture of chitosans, and hybridoma clones were screened for specific binders, resulting in the isolation of a single clone secreting a chitosan-specific IgM, mAbG7. In ELISAs, the antibody could bind to chitosans of varying composition, but demonstrated the highest affinity for chitosans with lower degrees of acetylation (DA) and very poor binding to chitin. We tested the ability of the antibody to bind to chitosan in situ, using preparations of fungal cell walls. Immunofluorescence microscopy confirmed that the antibody bound strongly to the cell walls of fungi with high levels of chitosan, whereas poor staining was observed in those species with cell walls of predominantly chitin or cellulose. The potential use of this antibody for the detection of fungal contamination and the protection of plants against fungal pathogens is discussed.

• Journal of Microbiology and Biotechnology
• /
• 제17권6호
• /
• pp.1036-1040
• /
• 2007

Sodium butyrate (NaBu) has been used to enhance protein expression levels in mammalian cell culture. To determine the clonal variability of recombinant Chinese hamster ovary (rCHO) cells in response to NaBu addition regarding specific antibody productivity $(q_{Ab})$, three rCHO clones were subjected to different concentrations of NaBu. For all three clones, NaBu addition inhibited cell growth and decreased cell viability in a dose-dependent manner. On the other hand, the enhancing effect of NaBu on $q_{Ab}$ varied significantly among the clones. NaBu addition enhanced the antibody production of only one clone. RT-PCR analysis revealed that the changes in $q_{Ab}$ correlated linearly with those of the mRNA transcription level. Thus, it was concluded that the different enhancing effects of NaBu on protein expression in rCHO cell clones resulted from their different mRNA transcription levels.