• Title, Summary, Keyword: antibody

Search Result 3,917, Processing Time 0.048 seconds

Strategies and Advancement in Antibody-Drug Conjugate Optimization for Targeted Cancer Therapeutics

  • Kim, Eunhee G.;Kim, Kristine M.
    • Biomolecules & Therapeutics
    • /
    • v.23 no.6
    • /
    • pp.493-509
    • /
    • 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.

Specific Targeting of Fluorescein Isothiocyanate with Ep-CAM Antibody(Specific targeting of FITC with Ep-CAM Antibody)

  • Lee, Young-Tae;Tae, Gun-Sik
    • Journal of Photoscience
    • /
    • v.10 no.3
    • /
    • pp.237-240
    • /
    • 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.

  • PDF

Synthetic approach to the generation of antibody diversity

  • Shim, Hyunbo
    • BMB Reports
    • /
    • v.48 no.9
    • /
    • 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]

Generation, Diversity Determination, and Application to Antibody Selection of a Human Naïve Fab Library

  • Kim, Sangkyu;Park, Insoo;Park, Seung Gu;Cho, Seulki;Kim, Jin Hong;S.Ipper, Nagesh;Choi, Sun Shim;Lee, Eung Suk;Hong, Hyo Jeong
    • Molecules and Cells
    • /
    • v.40 no.9
    • /
    • pp.655-666
    • /
    • 2017
  • We constructed a large $na{\ddot{i}}ve$ human Fab library ($3{\times}10^{10}$ colonies) from the lymphocytes of 809 human donors, assessed available diversities of the heavy-chain variable (VH) and ${\kappa}$ light-chain variable (VK) domain repertoires, and validated the library by selecting Fabs against 10 therapeutically relevant antigens by phage display. We obtained a database of unique 7,373 VH and 41,804 VK sequences by 454 pyrosequencing, and analyzed the repertoires. The distribution of VH and VK subfamilies and germline genes in our antibody repertoires slightly differed from those in earlier published natural antibody libraries. The frequency of somatic hypermutations (SHMs) in heavy-chain complementarity determining region (HCDR)1 and HCDR2 are higher compared with the natural IgM repertoire. Analysis of position-specific SHMs in CDRs indicates that asparagine, threonine, arginine, aspartate and phenylalanine are the most frequent non-germline residues on the antibody-antigen interface and are converted mostly from the germline residues, which are highly represented in germline SHM hotspots. The amino acid composition and length-dependent changes in amino acid frequencies of HCDR3 are similar to those in previous reports, except that frequencies of aspartate and phenylalanine are a little higher in our repertoire. Taken together, the results show that this antibody library shares common features of natural antibody repertoires and also has unique features. The antibody library will be useful in the generation of human antibodies against diverse antigens, and the information about the diversity of natural antibody repertoires will be valuable in the future design of synthetic human antibody libraries with high functional diversity.

A Study on Protection of Maternal Antibody against Hantavirus in Rats

  • Park Sang-Wook;Bae Hyung-Joon;Kim Tai-Jeon;Moon Hi-Joo;Cho Kyu-Bong;Woo Young-Dae
    • Biomedical Science Letters
    • /
    • v.11 no.1
    • /
    • pp.71-77
    • /
    • 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.

  • PDF

Cell-Specific Targeting of Texas Red with Anti-Ep-CAM Antibody

  • Lee, Soo-Chul;Tae, Gun-Sik
    • Journal of Photoscience
    • /
    • v.12 no.3
    • /
    • pp.123-127
    • /
    • 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.

  • PDF

Detection of antibody to porcine reproductive and respiratory syndrome virus from pig sera collected during the period of January to December 2000

  • Jung, Hae-Sun;Kim, Su-Mi;Kim, Jong-Taik;Han, Tae-Uk;Kang, Shien-Young;Shin, Kwang-Soon;Kim, Chul-Joong;Park, Bae-Keun;Kim, Hyun-Soo
    • Korean Journal of Veterinary Service
    • /
    • v.24 no.4
    • /
    • pp.343-346
    • /
    • 2001
  • During the period of January to December 2000, a total of 3,505 swine sera was collected from 208 farms, which are located throughout country, for the diagnosis of porcine reproductive and respiratory syndrome(PRRS). The antibody to porcine reproductive and respiratory syndrome virus(PRRS) was tested by indirect immunofluorescent antibody(IFA) test. Of 208 farms tested, at least one or more than one pigs was positive for PRRSV antibody in 188(90.4%) farms. The overall seroprevalence of PRRSV antibody was 45.1% (1581/3505). Most pigs were infected with PRRSV at around 50- to 60-day old. The seroprevalence of antibody varied with age. The highest seroprevalence of PRRSV antibody was observed in the growing pigs at around 80-day old. About one-thirds of adult pigs including boar, gilt and sow were positive to PRRSV antibody. In many farms, the infection of PRRSV was chronic and confined to grower and/or finisher. However, antibody was detected from all production phase in some farms.

  • PDF

Site-directed Immobilization of Antibody onto Solid Surfaces for the Construction of Immunochip

  • Paek, Se-Hwan;Cho, Il-Hoon;Paek, Eui-Hwan;Lee, Haewon;Park, Jeong-Woo
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.9 no.2
    • /
    • pp.112-117
    • /
    • 2004
  • The performance of an immuno-analytical system can be assessed in terms of its analytical sensitivity, i.e., the detection limit of an analyte, which is determined by the amount of analyte molecules bound to the capture antibody that has been immobilized onto a solid surface. To increase the number of the binding complexes, we have investigated a site-directed immobilization of an antibody that has the ability to resolve a current problem associated with a random arrangement of the insolubilized immunoglobulin. The binding molecules were chemically reduced to produce thiol groups that were limited at the hinge region, and then, the reduced products were coupled to biotin. This biotinylated antibody was bound to a streptavidin-coated surface via the streptavidin-biotin reaction. This method can control the orientation of the antibody molecules present on a solid surface and also can significantly reduce the possibility of steric hindrance in the antigen-antibody reactions. In a two-site immunoassay, the introduction of the site-directly immobilized antibody as the capture enhanced the sensitivity of analyte detection approximately 10 times compared to that of the antibody randomly coupled to biotin. Such a novel approach would offer a protocol of antibody immobilization in order for the possibility of constructing a high performance immunochip.

Antibody Engineering

  • Hong, Hyo-Jeong;Kim, Sun-Taek
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.7 no.3
    • /
    • pp.150-154
    • /
    • 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.

A Study on the Akabane disease antibody in Chung Buk-Do (충청북도 북부지방의 소 Akabane병 중화항체가 분포조사)

  • 최해연;정운선
    • Korean Journal of Veterinary Service
    • /
    • v.14 no.2
    • /
    • pp.154-158
    • /
    • 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.

  • PDF