• Title/Summary/Keyword: antibody engineering

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Growth Performance and Antibody Response of Broiler Chicks Fed Yeast Derived β-Glucan and Single-strain Probiotics

  • An, B.K.;Cho, B.L.;You, S.J.;Paik, H.D.;Chang, H.I.;Kim, S.W.;Yun, C.W.;Kang, C.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.7
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    • pp.1027-1032
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    • 2008
  • A study was conducted to evaluate the effects of dietary yeast derived ${\beta}$-glucan and single-strain probiotics on the growth performance and antibody response in broiler chicks. Six hundred and thirty 1-d-old male broiler chicks were divided into seven groups, placed into three pens per group (30 birds per pen) and fed one of seven non-medicated corn-SBM based experimental diets containing 0.025, 0.05 or 0.1% Saccharomyces cerevisiae ${\beta}$-glucan and 0.05, 0.1 or 0.2% Bacillus amyloliquefaciens (BA-pro, $1.3{\times}10^9/g$) or devoid of them for 5 wk. The body weight gains in groups fed diets containing 0.025 or 0.1% ${\beta}$-glucan, 0.1% or 0.2% BA-pro were significantly higher (p<0.05) than the control over 1-35 d. Feed conversion rates of groups fed ${\beta}$-glucan and BA-pro tended to be improved compared to the control group. There were no significant differences in the relative weights of liver, abdominal fat and breast muscle. No significant differences were observed in the activities of serum enzymes and concentrations of various cholesterol fractions. The antibody titers against Newcastle disease or infectious bronchitis virus in the chicks fed diets containing ${\beta}$-glucan and BA-pro were significantly higher (p<0.05) than in the control. The concentrations of cecal lactic acid bacteria in all groups fed BA-pro were significantly increased (p<0.05) compared to the control. These results indicated that dietary yeast derived ${\beta}$-glucan and BA-pro exerted growth-promoting and immune-enhancing effects in broiler chickens. In addition, BA-pro added to the diets modulated the profiles of cecal microflora, reflecting a potential to be beneficial microorganisms in chickens.

Production and Characterization of a Recombinant Antibody Neutralizing Botulinum Neurotoxin A (보툴리눔 신경독소 A를 중화하는 재조합 항체의 제조와 특성 분석)

  • Park, Hong-Gyu;Choi, Mieyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.295-301
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    • 2017
  • Botulinum neurotoxin (BoNT/A) is a neurotoxin that selectively attacks the peripheral cholinergic nerve endings. It is produced by Gram -positive, endospore-forming strict anaerobic bacteria, Clostridium botulinum. Since BoNT/A could be a biothreat agent, as well as a contaminator of food and water supplies, the development of sensitive assays for toxin detection and potent antitoxin for the treatment of intoxication is necessary. In this study, for the purpose of producing monoclonal antibodies (mAbs) that are capable of neutralizing Botulinum neurotoxin type A (BoNT/A), scFv (single-chain variable domain fragment) libraries from the rabbit antisera against BoNT/A was fused to a human IgG. The resulting recombinant scFvIgG antibody protein was expressed in stable cell lines and was purified using a protein A affinity chromatography. The efficacy of scFvIgG mAb was confirmed by ELISA and was evaluated for the neutralization of BoNT/A in vivo. Such an in vivo toxin neutralization assay was performed using mice. Although scFvIgG antibody proteins (10 ug) failed to fully protect the mice challenged with BoNT/A (100,000 $LD_{50}$), it significantly prolonged the survival time. These results suggest that scFvIgG mAb may be capable of neutralizing BoNT/A single-chain variable domain fragment.

Surface Plasmon Resonance Imaging Analysis of Hexahistidine-tagged Protein on the Gold Thin Film Coated with a Calix Crown Derivative

  • Chung, Bong-Hyun;Baek, Seung-Hak;Shin, Yong-Beom;Kim, Min-Gon;Ro, Hyeon-Su;Kim, Eun-Ki
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.2
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    • pp.143-146
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    • 2004
  • A surface plasmon resonance (SPR) imaging system was constructed and used to detect the hexahistidine-ubiquitin-tagged human parathyroid hormone fragment (His$\sub$6/-Ub-hPTHF(1-34)) expressed in Escherichia coli. The hexahistidine-specific antibody was immobilized on a thin gold film coated with ProLinker$\^$TM/ B, a novel calixcrown derivative with a bifunctional coupling property that permits efficient immobilizaton of capture proteins on solid matrices. The soluble and insoluble fractions of an E. coli cell lysate were spotted onto the antibody-coated gold chip, which was then washed with buffer (pH 7.4) solution and dried. SPR imaging measurements were carried out to detect the expressed His$\sub$6/-Ub-hPTHF(1-34). There was no discernible protein image in the uninduced cell lysate, indicating that non-specific binding of contaminant proteins did not occur on the gold chip surface. It is expected that the approach used here to detect affinity-tagged recombinant proteins using an SPR imaging technique could be used as a powerful tool for the analyses of a number of proteins in a high-throughput mode.

Hep88 mAb-Mediated Paraptosis-Like Apoptosis in HepG2 Cells via Downstream Upregulation and Activation of Caspase-3, Caspase-8 and Caspase-9

  • Mitupatum, Thantip;Aree, Kalaya;Kittisenachai, Suthathip;Roytrakul, Sittiruk;Puthong, Songchan;Kangsadalampai, Sasichai;Rojpibulstit, Panadda
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.1771-1779
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    • 2015
  • Hepatocellular carcinoma (HCC) is a leading cause of cancer death worldwide. Presently, targeted therapy via monoclonal antibodies to specific tumor-associated antigens is being continuously developed. Hep88 mAb has proven to exert tumoricidal effects on the HepG2 cell via a paraptosis-like morphology. To verify the pathway, we then demonstrated downstream up-regulation of caspase-3, caspase-8 and caspase-9, assessingmRNA expression by real-time PCR and associated enzyme activity by colorimetric assay. Active caspase-3 determination was also accomplished by flow cytometry. Active caspase-3 expression was increased by Hep88 mAb treatment in a dose-and time-dependent manner. All of the results indicated that Hep88 mAb induced programmed cell death in the HepG2 cell line from paraptosis-like to apoptosis by downstream induction of caspases. These conclusions imply that Hep88mAb might be a promising tool for the effective treatment of HCC in the future.

Effects of Gal-13 on the Content of Immunoglobulin, Proliferation of Lymphocyte and Antibody Titers after Vaccination with Infectious Bursal Disease Virus Vaccine in Chickens

  • Yang, Yurong;Jiang, Yibao;She, Ruiping;Peng, Kaisong;Zhou, Xuemei;Yin, Qingqiang;Wang, Decheng;Liu, Tianlong;Bao, Huihui
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.3
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    • pp.405-411
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    • 2007
  • Gal-13 is an antimicrobial peptide isolated from chicken intestine. Ninety chickens were randomly divided into two groups (45 chickens for each group) to determine the effect of oral administration of Gal-13 on the acquired immune response. The chickens in the first group were fed a diet without Gal-13 as the control, and the chickens in the second group were fed the same diet, except that Gal-13 ($1{\mu}g/ml$) was suspended in drinking water just after hatching. Samples of blood, thymus, bursa of fabricius and spleen were taken at day 1, 4, 7, 10 and 17. The chickens in both groups received infectious bursal disease virus vaccine at day 20, and then sera samples were collected for analysis at 14, 21, 28 and 35 days after vaccination. The results showed: (1) Gal-13 could enhance the content of immunoglobulin (Ig)G at the age of 4 to10 days (p<0.05) and IgM at the age of 4 and 10 days (p<0.05) in the serum; (2) In vitro experiments showed that Gal-13 (0.625-1.250${\mu}g/ml$) enhanced the proliferation of peripheral blood lymphocytes of the chickens stimulated by lipopolysaccharide (LPS) and concanavlin A (ConA). Compared to the control, Gal-13 (1 ${\mu}g/ml$) enhanced the proliferation of bursa lymphocytes at 17 days of age (p<0.01) and thymus lymphocytes at 7 days of age (p<0.01), but restrained lymphocyte proliferation in chicken spleen and differed significantly at day 10 (p<0.01); (3) Gal-13 enhanced infectious bursal disease virus antibody in sera of chickens 21 days after infectious bursal disease virus vaccine administration (p<0.05). These results suggested that Gal-13 could modulate adaptive immune responses of chickens.

A Biosensor for the Rapid Detection of the Fungicide Iprovalicarb Residuess (살균제 Iprovalicarb 잔류물의 신속한 검출을 위한 바이오센서)

  • Cho, Han-Keun;Kim, Woon-Ho;Kyung, Kee-Sung;Lee, Eun-Young
    • Journal of Biosystems Engineering
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    • v.32 no.6
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    • pp.440-447
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    • 2007
  • In this study, a biosensor was developed using an enzyme-linked immunosorbent assay (ELISA) to rapidly measure the fungicide iprovalicarb residues in agricultural products. The biosensor was designed to include micro-pumps and solenoid valves for fluid transport, a spectrophotometer cuvet as a reaction chamber, a photodiode with a light-emitting diode for optical density measurement, and a control microcomputer to implement assay. The rate of change in optical density of the cuvet was read as final signal output. Micro-pumps were evaluated to investigate their delivery capability, the highest values of the error and the coefficient of variation were 4.3% and 4.6% respectively. As the incubation period was reduced from 15 minutes to 11 minutes to shorten the total processing time, the sensor sensitivity was decreased as the antibody dilution ratio was reduced to a half. The maximum usable period of the coated cuvet was found to be two days with 1% error limit. To predict the concentration of the iprovalicarb residue in agricultural products, a linear calibration model was obtained with r-square values of 0.992 for potato and 0.985 for onion. In validation test for the samples of potatoes and onions against the high performance liquid chromatography, very high correlation values were obtained as 0.996 and 0.993 respectively. Using the cuvet immobilized with antigen, it took 21-minutes for the biosensor to complete the measuring process of the iprovalicarb residues.

Norovirus Targeted Bioreceptor Screening Method based on Lateral Flow Immunoassay (LFIA) (노로바이러스 검출을 위한 측면유동면역분석법 기반의 바이오리셉터 선별기법 개발)

  • Huisoo, Jang;Hyeonji, Cho;Tae-Joon, Jeon;Sun Min, Kim
    • Journal of the Korean Society of Visualization
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    • v.20 no.3
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    • pp.136-145
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    • 2022
  • Later flow immunoassay (LFIA) is a protein analytical method based on immunoreaction. On the LFIA based protein analytical method, bioreceptor molecule plays a key role, and so a system that evaluates and manages the binding affinity of bioreceptor is needed to secure detection reliability. In this study, Lateral Flow Immunoassay based rapid Bioreceptor Screening Method (rBSM) is presented that provide a simple and quick evaluating method for the binding affinity to the target protein of the antibody as model bioreceptor. To verify this evaluation method, Virus-like particles (VLP) and anti-VLP antibodies are selected as a model norovirus, which is target protein, and the candidate bioreceptors respectively. Among the 5 different candidate antibodies, appropriate antibody could be sorted out within 30 minutes through rBSM. In addition, selected antibodies were applied to two representative LFIA based techniques, sandwich assay and competitive assay. Among these methods, sandwich assay showed more effective VLP detection method. Through applying selected antibodies and techniques to the commercialized mass production lines, an VLP detecting LFIA kit was developed with a detection limit of 1012 copies/g of VLPs in real samples. Since this proposed method in this study could be easily transformable into other combinations with bioreceptors, it is expected that this technique would be applied to LFIA kit development system and bioreceptor quality management.

Development of Chemiluminescent Immunosensor Array for GMO

  • Jung, Woo-Sung;Hwang, Ok-Hwa;Jang, Hye-Ji;Paek, Eui-Hwan;Park, Won-Mok;Paek, Se-Hwan
    • 한국생물공학회:학술대회논문집
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    • 2003.10a
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    • pp.683-686
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    • 2003
  • While genetically modified organisms (GMOs) are producing in many countries, issues related to safeties of GMOs as foods for human have risen. Because of such potential problems, the development of an indication system regarding GMO content contained in foods has been required. Particularly, an immune-chip, as widely demanded diagnostic tool for functional, structural analyses of proteins, has been investigated to simultaneously measure different analytes. We have developed methods for immobilizing antibody on glass surfaces as substrate and for generating chemiluminometric signals.

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