• Biomolecules & Therapeutics
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• v.23 no.6
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• pp.493-509
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• 2015

Antibody-drug conjugates utilize the antibody as a delivery vehicle for highly potent cytotoxic molecules with specificity for tumor-associated antigens for cancer therapy. Critical parameters that govern successful antibody-drug conjugate development for clinical use include the selection of the tumor target antigen, the antibody against the target, the cytotoxic molecule, the linker bridging the cytotoxic molecule and the antibody, and the conjugation chemistry used for the attachment of the cytotoxic molecule to the antibody. Advancements in these core antibody-drug conjugate technology are reflected by recent approval of Adectris$^{(R)}$(anti-CD30-drug conjugate) and Kadcyla$^{(R)}$(anti-HER2 drug conjugate). The potential approval of an anti-CD22 conjugate and promising new clinical data for anti-CD19 and anti-CD33 conjugates are additional advancements. Enrichment of antibody-drug conjugates with newly developed potent cytotoxic molecules and linkers are also in the pipeline for various tumor targets. However, the complexity of antibody-drug conjugate components, conjugation methods, and off-target toxicities still pose challenges for the strategic design of antibody-drug conjugates to achieve their fullest therapeutic potential. This review will discuss the emergence of clinical antibody-drug conjugates, current trends in optimization strategies, and recent study results for antibody-drug conjugates that have incorporated the latest optimization strategies. Future challenges and perspectives toward making antibody-drug conjugates more amendable for broader disease indications are also discussed.

• Journal of Photoscience
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• v.10 no.3
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• pp.237-240
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• 2003

The tetradecameric peptide (K47-K60) near the NH$_2$-terminal region of epithelial-cell adhesion molecule (Ep-CAM) was chosen as antigenic site and a polyclonal antibody was generated, which could recognize Ep-CAM from the mouse colon tissue or the colon cancer cell, CT-26, in Western blot analysis. Then, the fluorescein isothiocyanate (FITC), a fluorescence dye, was conjugated with the affinity purified Ep-CAM antibody using thiocyanate and the amino groups of FITC and antibody, respectively. The molar ratio of FITC to antibody was estimated approximately 1.86 to 1.00 by measuring the optical densities at 492 nm and 280 nm. Ep-CAM antibody-FITC conjugate was then used for immunohistochemistry of the CT-26 cells. Judging from the shapes formed by fluorescence, the Ep-CAM antibody could delivered FITC to the surface of cells in which Ep-CAM was expressed. This result implies that Ep-CAM antibody could be also used for the tissue-specific delivery of the photosensitizer to the target protein via antigen-antibody interaction.

• BMB Reports
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• v.48 no.9
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• pp.489-494
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• 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]

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.4
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• pp.129-135
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• 2020

In a relatively short period, monoclonal antibodies have made dramatic success as therapeutics for various diseases such as cancers and autoimmune diseases and become an important development items for many pharmaceutical companies. In order to develop antibody drug, it is important to investigate the structural characteristics of both antibody and antigen. NMR studies on antibody are extremely challenging due to big huddles such as a big size of protein and isotope labeling, nevertheless, several studies have been reported in 10 years. Here, we analyzed 95 papers dealing with antibody-related NMR studies reported in recent 10 years. We categorized papers into 3 types: 1) structural characterization of antibody, 2) structural characterization of antigen using antibody, 3) amyloidosis caused by fragment of antibody. This work would shed new light on antibody-related NMR studies.

• Biomedical Science Letters
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• v.11 no.1
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• pp.71-77
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• 2005

The etiologic agents of haemorragic fever with ranal syndrom (HFRS) in Korea are Hantaan and Seoul virus in the genus Hantavirus, family Bunyaviridae. In order to elucidate the role of maternal immunity to Hantavirus infection in rats, the protective effect of the maternal antibody were studies by using rats experimentally infected with Seoul virus strain HR80-39. Antibody titers of sera and viral antigen against Seoul virus were investigated by indirect immunofluorscence antibody technique (IFA). The dam sera had IFA antibody titers ranging from 1:128 to 1:1,024 after parturition. In fetuses, IFA antibody titers ranged from 1: 16 to 1:64 just after birth, increased to peak titers ranged from 1:256 to 1:1,024 in the 2nd week after birth. Challenged newborn rats had IFA antibody titers ranging from 1:64 to 1:1,024 after inoculation. No viral antigen was detected in lungs or other organs of the newborn rats. The maternal antibody to Seoul virus was transferred prenatally through placenta and postnatally via colostrum from immune dams to their offspring. These results demonstrated that maternal antibody to Seoul virus was quite effective in protecting newborn rats against same virus infection.

• Journal of Photoscience
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• v.12 no.3
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• pp.123-127
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• 2005

The polyclonal antibody was generated against the peptide fragment of 62 amino acid residues (D 181-T242) near the COOH-terminal region of the extracellular domain of epithelial-cell adhesion molecule (Ep-CAM) and shown to be able to recognize Ep-CAM in competitive ELISA. Then, sulforhodamine 101 acid chloride (so called Texas red), a fluorescence dye, was conjugated to the affinity-purified anti-Ep-CAM antibody utilizing the reaction between the aliphatic amines of antibody and the sulfonyl chloride of Texas red. The molar ratio of Texas red to antibody was estimated to be approximately 1.86 by measuring optical densities at 280 nm and 596 nm, implying that the two molecules of Texas red at most were conjugated to antibody. The anti-Ep-CAM antibody-Texas red conjugate was then used for immunohistochemistry of CT-26 murine colon carcinoma cells. Based upon the fluorescence microscope images, anti-Ep-CAM antibody is able to deliver Texas red specifically to the surface of CT-26 cells on which Ep-CAM was actively expressed. This result indicates that anti-Ep-CAM antibody could be useful for the tissue-specific delivery of photosensitizers via antigen-antibody interaction.

• Korean Journal of Veterinary Service
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• v.17 no.1
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• pp.9-18
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• 1994

Neutralized antibody titer of Akabane disease virus were performed from 810 dairy cows in 45 farming households from May 1992 to December 1993 in Incheon area. The 503 dairy cows at the 21 farming household were conducted from May to December 1992, 307 cows were from January to December 1993 The results obtained are summarized as follows 1. Evaluation of neutralized antibody titer of 810 dairy cows tested during two yews revealed that 68.1% (552 hearts) , during the four year revealed that 69.6% (350 heads), the later year was 65.8%(202 heads ) was more than antibody titer 16. 2. Antibody investigation according to area and years, showed no significant difference in the whole area and both years as 65-73% from 1992, and as 65-70% from 1993 had an antibody titer of above 16 or more. 3. Antibody investigation according to age, showed that 34.4% of cows aged below 2 had a titer of above 16, compared with 80.8% for cows aged above 5. It demonstrated that the younger cows had the lower titer level, and the older the higher. 4. Monthly variation of antibody titer showed that the highest level of antibody titer was observed in September, the lowest was in June. It meant that the best periods of vaccination were April, May, June. 5. The result of epidemidogical study to 40 farming households showed that 35 farms (87.5%) had abortions of which were 14 stillbirths, 5 abnormal births, and 13 farms (32.5%) had vaccination.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.3
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• pp.150-154
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• 2002

Monoclonal antibodies (Mabs) have been used as diagnostic and analytical reagents since hybridoma technology was invented in 1975. In recent years, antibodies have become increasingly accepted as therapeutics for human diseases, particularly for cancer, viral infection and autoimmune disorders. An indication of the emerging significance of antibody-based therapeutics is that over a third of the proteins currently undergoing clinical trials in the United States are antibodies. Until the late 1980's, antibody technology relied primarily on animal immunization and the expression of engineered antibodies. However, the development of methods for the expression of antibody fragments in bacteria and powerful techniques for screening combinatorial libraries, together with the accumulating structure-function data base of antibodies, have opened unlimited opportunities for the engineering of antibodies with tailor-made properties for specific applications. Antibodies of low immunogenicity, suitable for human therapy and in vivo diagnosis, can now be developed with relative ease. Here, antibody structure-function and antibody engineering technologies are described.

• 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.

• Korean Journal of Veterinary Service
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• v.14 no.2
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• pp.154-158
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• 1991

To investigate the Akabane antibody in the cattle with the serological test in Chung Chung Buk Do from May to Nov 1191. The result are summarized as follows. 1. Breed in cattle reacted as positive condition in Akabane antibody 76 heads(42%) in 180 cattles reacted as positive condition in Akabane antibody, 23 heads(51%) in 45 Korea native cattle reacted as positive condition in Akabane antibody. 2. During 5, 9, 10, 11 month, Akabane antibody in cattle is over 45%. 3. Less of 2 years old and over 4 years old cattle are Akabane antibody in cattle is over 40%. 4. The relation of titer of 2 folds of dilution HA and 10 folds of dilution TCID$_{50}$ was same relation.n.