• Title/Summary/Keyword: antibody engineering

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In vitro neural differentiation of human embryonic stem cells

  • Park, Jae-Hyun;Shin, Hwa-Yean;Kang, Yun-Hee;Kang, Young-Kook;Lee, Jung-Bok;Yoon, Hyun-Soo;Ryu, Chun-Jeih;Myung, Pyung-Keun;Hong, Hyo-Jeong
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.164.2-164.2
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    • 2003
  • Human embryonic stem (ES) cell lines derived from the inner cell mass of human blastocysts have potential to differentiate into any cell types. We have established in vitro neural differentiation of human ES cells. After the formation of embroid bodies (EBs), the differentiating EBs formed neural tube-like rosettes in the presence of basic fibroblast growth factor (bFGF). The rosettes were selectively isolated by the treatment of dispase and cultured in a medium for human neural precursors in the presence of bFGF. (omitted)

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Expression and Secretion of Heterologous Protein in Yeast

  • Kim, Moo-Kyum;Song, Moo-Young;Yu, Myeong-Hee;Yu, Myeong-Hee;Park, Hee-Moon;Kim, Jinmi
    • Korean Journal of Microbiology
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    • v.30 no.2
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    • pp.108-112
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    • 1992
  • To investigate the expression and the secretion of heterologous proteins in yeast, we constructed an yeast secretion vector and produced a human secretory protein, .alpha.-1-antitrypsin (.alpha.-1-AT), from yeast cells. The secretion vector pGAT8 was constructed by inserting the signal sequence of yeast acid phosphatase gene (PH05) into the .alpha.1-AT expression vector pGAT6 which contained .alpha.-1-AT cDNA fused to GAL10-CYC1 promotor. The .alpha.-1-AT was produced efficiently in the yeast cells transformed with plasmid pGAT8, which was onfirmed both by the .alpha.-1-AT activity assay and by the immunoblot method using .alpha.-1-AT antibody. We also showed the secretion of .alpha.-1-AT into the culture media and into the periplasmic space by immunoblot.

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LIGHT is Expressed in Foam Cells and Involved in Destabilization of Atherosclerotic Plaques through Induction of Matrix Metalloproteinase-9 and IL-8

  • Kim, Won-Jung;Lee, Won-Ha
    • IMMUNE NETWORK
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    • v.4 no.2
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    • pp.116-122
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    • 2004
  • Background: LIGHT (TNFSF14) is a member of tumor necrosis factor superfamily and is the ligand for TR2 (TNFRSF14/HVEM). LIGHT is known to have proinflammatory roles in atherosclerosis. Methods: To find out the expression pattern of LIGHT in atherosclerotic plaques, immunohistochemical analysis was performed on human carotid atherosclerotic plaque specimens. LIGHT induced atherogenic events using human monocytic cell line THP-1 were also investigated. Results: Immunohistochemical analysis revealed expression of LIGHT and TR2 in foam cell rich regions in the atherosclerotic plaques. Double immunohistochemical analysis further confirmed the expression of LIGHT in foam cells. Stimulation of THP-1 cells, which express TR2, with either recombinant LIGHT or immobilized anti-TR2 monoclonal antibody induced interleukin-8 and matrix metalloproteinase(MMP)-9. Electrophoretic mobility shift assay demonstrated that LIGHT induces nuclear localization of transcription factor, nuclear factor $(NF)-{\kappa}B$. LIGHT induced activation of MMP-9 is mediated by $NF-{\kappa}B$, since treatment of THP-1 cells with the $NF-{\kappa}B$ inhibitor PDTC (pyrrolidine dithiocarbamate) completely blocked the activation of MMP-9. Conclusion: These data indicate that LIGHT is expressed in foam cells in atherosclerotic plaques and is involved in atherogenesis through activation of pro-atherogenic cytokine IL-8 and destabilization of plaque by inducing matrix degrading enzyme.

Cooperative Strategies and Swarm Behavior in Distributed Autonomous Robotic Systems based on Artificial Immune System

  • Sim, Kwee-bo;Lee, Dong-wook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.7
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    • pp.591-597
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    • 2001
  • In this paper, we propose a method of cooperative control (T-cell modeling) and selection of group behavior strategy (B-cell modeling) based on immune system in distributed autonomous robotic system (DARS). Immune system is living body's self-protection and self-maintenance system. These features can be applied to decision making of optimal swarm behavior in dynamically changing environment. For applying immune system to DARS, a robot is regarded as a B-cell, each environmental condition as an antigen, a behavior strategy as an antibody and control parameter as a T-cell respectively. The executing process of proposed method is as follows. When the environmental condition changes, a robot selects an appropriate behavior strategy. And its behavior strategy is stimulated and suppressed by other robot using communication. Finally much stimulated strategy is adopted as a swarm behavior strategy. This control school is based on clonal selection and idiotopic network hypothesis. And it is used for decision making of optimal swarm strategy. By T-cell modeling, adaptation ability of robot is enhanced in dynamic environments.

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Fabrication of a paper-based ELISA to detect polygalacturonase (Polygalacturonase를 검출하기 위한 종이 기반의 효소결합 면역반응 센서 제작)

  • Hwang, Young-Kug;Kim, Ji-Kwan;Lee, Young Hwan;Choi, Young-Soo
    • Journal of Sensor Science and Technology
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    • v.30 no.5
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    • pp.337-341
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    • 2021
  • In this paper, we describe the fabrication of a paper-based enzyme-linked immunosorbent assay (ELISA) to detect polygalacturonase (PG), which is used as a biomarker to determine whether a plant is infected with a disease. The proposed paper-based ELISA can analyze the concentration of PG in a short time using a small sample compared to the traditional ELISA, which is generally performed using a well plate. To increase the resolution of the sensor, we optimized the dilution ratio of the HRP-conjugated goat anti-rabbit IgG antibody and the dilution ratio of the anti-PG and HRP-conjugated goat anti-rabbit IgG antibodies. Furthermore, for quantitative analysis of PG concentration, Delta RGB analysis was conducted to detect color changes in the sensing window displayed by the PG samples at various concentrations. Based on the experiment, the fabricated paper-based ELISA could measure at least 0.25 ㎍ of PG and the measurement range was 0.25-2 ㎍. Therefore, the paper-based ELISA for detecting PG is expected to be able to determine the presence or absence of disease in crops at the infection stage in the future.

Characterization of the Physical Form of Allergenic Cry j 1 in the Urban Atmosphere and Determination of Cry j 1 Denaturation by Air Pollutants

  • Wang, Qingyue;Morita, Jun;Gong, Xiumin;Nakamura, Shinichi;Suzuki, Miho;Lu, Senlin;Sekiguchi, Kazuhiko;Nakajima, Takuya;Nakajima, Daisuke;Miwa, Makoto
    • Asian Journal of Atmospheric Environment
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    • v.6 no.1
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    • pp.33-40
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    • 2012
  • In this study, we characterized the physical form of allergenic Cry j 1 in the urban atmosphere. Through an immunofluorescence antibody method, we showed that allergenic Cry j 1 exists as fine particles (${\leq}1.1{\mu}m$). To determine Cry j 1 concentrations and its particle size distribution, we used the ELISA method to confirm that most Cry j 1 exists as fine particles in the urban atmosphere and is found at high concentrations on fine day next to rainy day. Furthermore, we evaluated Cry j 1 denaturation by using the Biacore J system based on the surface plasmon resonence (SPR) principle and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We showed that the dissociation constant ($K_D$) of Cry j 1 that has been exposed to urban polluted air is lower ($1.76{\times}10^{-14}$ M) than that of Cry j 1 ($1.32{\times}10^{-9}-3.37{\times}10^{-9}$ M) of original pollen grains that has not been exposed to air pollutants. Cry j 1 turns into low molecular weight proteins by reacting with various acidic solutions. In sum, we showed that allergenic Cry j 1 exists as fine particles that can deposit in the lower respiratory tract. This finding clarifies the relationship between Japanese cedar pollinosis and air pollutants.

Microfluidic Immuno-Sensor Chip using Electrical Detection System (전기 검출 시스템을 이용한 Microfluidic Immuno-Sensor Chip)

  • Maeng, Joon-Ho;Lee, Byung-Chul;Cho, Chul-Ho;Ko, Yong-Jun;Ahn, Yoo-Min;Cho, Nahm-Gyoo;Lee, Seoung-Hwan;Hwang, Seung-Yong
    • KSBB Journal
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    • v.21 no.5
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    • pp.325-330
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    • 2006
  • This study presents the characterization of an integrated portable microfluidic electrical detection system for fast and low volume immunoassay using polystyrene microbead, which are used as immobilization surfaces. In our chip, a filtration method using the microbead was adopted for sample immobilization and immunogold silver staining(IGSS) was used to increase the electrical signal. The chip is composed of an inexpensive and biocompatible Polydimethylsiloxane(PDMS) layer and Pyrex glass substrate. Platinum microelectrodes for electric signal detection were fabricated on the substrate and microchannel and pillar-type microfilters were formed in the PDMS layer. With a fabricated chip, we reacted antigen and antibody according to the procedures. Then, silver enhancer was injected to increase the size of nanogold particles tagged with the second antibody. As a result, microbeads were connected to each other and formed an electrical bridge between microelectrodes. Resistance measured through the electrodes showed a difference of two orders of magnitude between specific and nonspecific immuno-reactions. The detection limit was 10 ng/ml. The developed immunoassay chip reduced the total analysis time from 3 hours to 50 min. Fast and low-volume biochemical analysis has been successfully achieved with the developed microfilter and immuno-sensor chip, which is integrated to the microfluidic system.

Evaluation of liquid and powdered forms of polyclonal antibody preparation against Streptococcus bovis and Fusobacterium necrophorum in cattle adapted or not adapted to highly fermentable carbohydrate diets

  • Cassiano, Eduardo Cuellar Orlandi;Perna, Flavio Junior;Barros, Tarley Araujo;Marino, Carolina Tobias;Pacheco, Rodrigo Dias Lauritano;Ferreira, Fernanda Altieri;Millen, Danilo Domingues;Martins, Mauricio Furlan;Pugine, Silvana Marina Piccoli;de Melo, Mariza Pires;Beauchemin, Karen Ann;Meyer, Paula Marques;Arrigoni, Mario de Beni;Rodrigues, Paulo Henrique Mazza
    • Animal Bioscience
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    • v.34 no.1
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    • pp.74-84
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    • 2021
  • Objective: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet. Methods: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly. Results: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals. Conclusion: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

Correlation Between Auto-antibodies to Survivin and MUC1 Variable Number Tandem Repeats in Colorectal Cancer

  • Wang, Yu-Qian;Zhang, Hai-Hong;Liu, Chen-Lu;Xia, Qiu;Wu, Hui;Yu, Xiang-Hui;Kong, Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5557-5562
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    • 2012
  • Aim: The aim of this study was to investigate the frequency and correlation between auto-antibodies to survivin and MUC1 variable number tandem repeats (VNTR) in colorectal cancer (CRC), which can provide valuable information for the design of immunotherapeutic vaccines for this disease. Methods: Enzyme-linked immunosorbent assays (ELISA) were used to examine the level of auto-antibodies against survivin and MUC1 VNTR in the serum of 135 CRC patients and 95 healthy volunteers. Results: Using mean absorbance + 2 standard deviations (SD) of the healthy samples as a cut-off value, the positive rates of survivin and MUC1 VNTR auto-antibodies in CRC were 31.1% and 18.5%, respectively. Altogether, the survivin and MUC1 VNTR positive samples accounted for 36.3% of the CRC patients, and 7.4% were positive for both. Conclusion: A significant positive correlation was found between levels of specific antibodies against survivin and MUC1 VNTR in the serum of CRC patients (r = 0.3652, P < 0.0001), suggesting that vaccines against both targets would elicit immune responses more effectively.

Recombinant DNA and Protein Vaccines for Foot-and-mouth Disease Induce Humoral and Cellular Immune Responses in Mice

  • Bae, Ji-Young;Moon, Sun-Hwa;Choi, Jung-Ah;Park, Jong-Sug;Hahn, Bum-Soo;Kim, Ki-Yong;Kim, Byung-Han;Song, Jae-Young;Kwon, Dae-Hyuck;Lee, Suk-Chan;Kim, Jong-Bum;Yang, Joo-Sung
    • IMMUNE NETWORK
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    • v.9 no.6
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    • pp.265-273
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    • 2009
  • Foot-and-mouth disease virus (FMDV) is a small single-stranded RNA virus which belongs to the family Picornaviridae, genus Apthovirus. It is a principal cause of FMD which is highly contagious in livestock. In a wild type virus infection, infected animals usually elicit antibodies against structural and non-structural protein of FMDV. A structural protein, VP1, is involved in neutralization of virus particle, and has both B and T cell epitopes. A RNA-dependent RNA polymerase, 3D, is highly conserved among other serotypes and strongly immunogenic, therefore, we selected VP1 and 3D as vaccine targets. VP1 and 3D genes were codon-optimized to enhance protein expression level and cloned into mammalian expression vector. To produce recombinant protein, VP1 and 3D genes were also cloned into pET vector. The VP1 and 3D DNA or proteins were co-immunized into 5 weeks old BALB/C mice. Antigen-specific serum antibody (Ab) responses were detected by Ab ELISA. Cellular immune response against VP1 and 3D was confirmed by ELISpot assay. The results showed that all DNA- and protein-immunized groups induced cellular immune responses, suggesting that both DNA and recombinant protein vaccine administration efficiently induced Ag-specific humoral and cellular immune responses.