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Heggestad JT, Fontes CM, Joh DY, Hucknall AM, Chilkoti A. In Pursuit of Zero 2.0: Recent Developments in Nonfouling Polymer Brushes for Immunoassays. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1903285. [PMID: 31782843 PMCID: PMC6986790 DOI: 10.1002/adma.201903285] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 10/17/2019] [Indexed: 05/11/2023]
Abstract
"Nonfouling" polymer brush surfaces can greatly improve the performance of in vitro diagnostic (IVD) assays due to the reduction of nonspecific protein adsorption and consequent improvement of signal-to-noise ratios. The development of synthetic polymer brush architectures that suppress adventitious protein adsorption is reviewed, and their integration into surface plasmon resonance and fluorescent sandwich immunoassay formats is discussed. Also, highlighted is a novel, self-contained immunoassay platform (the D4 assay) that transforms time-consuming laboratory-based assays into a user-friendly and point-of-care format with a sensitivity and specificity comparable or better than standard enzyme-linked immunosorbent assay (ELISA) directly from unprocessed samples. These advancements clearly demonstrate the utility of nonfouling polymer brushes as a substrate for ultrasensitive and robust diagnostic assays that may be suitable for clinical testing, in field and laboratory settings.
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Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
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2
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Kaya T, Nagatoishi S, Nagae K, Nakamura Y, Tsumoto K. Highly sensitive biomolecular interaction detection method using optical bound/free separation with grating-coupled surface plasmon field-enhanced fluorescence spectroscopy (GC-SPFS). PLoS One 2019; 14:e0220578. [PMID: 31369601 PMCID: PMC6675060 DOI: 10.1371/journal.pone.0220578] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 07/18/2019] [Indexed: 01/06/2023] Open
Abstract
Grating-coupled surface plasmon field-enhanced fluorescence spectroscopy (GC-SPFS) with optical bound/free (B/F) separation technique was developed by employing a highly directional fluorescence with polarization of surface plasmon-coupled emission (SPCE) to realize highly sensitive immunoassay regardless of the ligand affinity. A highly sensitive immunoassay system with GC-SPFS was constructed using a plastic sensor chip reproducibly fabricated in-house by nanoimprinting and applied to the quantitative detection of an anti-lysozyme single-domain antibody (sdAb), to compare conventional washing B/F separation with optical B/F separation. Differences in the affinity of the anti-lysozyme sdAb, induced by artificial mutation of only one amino acid residue in the variable domain were attributed to higher sensitivity than that of the conventional Biacore surface plasmon resonance (SPR) system. The detection limit (LOD; means of six replicates of the zero standard plus three standard deviations) of the GC-SPFS immunoassay with optical B/F separation, was estimated to be 1.2 ng/ml with the low-affinity ligand (mutant sdAb Y52A: KD level was of the order of 10−7 ~ 10−6 M) and was clearly improved as compared to that (LOD: 9.4 ng/ml) obtained with the conventional washing B/F separation. These results indicate that GC-SPFS with the optical B/F separation technique offers opportunities to re-evaluate low-affinity biomaterials that are neither fully utilized nor widespread, and could facilitate the creation of novel and innovative methods in drug and diagnostic development.
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Affiliation(s)
- Takatoshi Kaya
- Corporate R&D Headquarters, Konica Minolta, Inc., Hino-shi, Tokyo, Japan
- * E-mail: (TK); (KT)
| | - Satoru Nagatoishi
- Institute of Medical Science, the University of Tokyo, Tokyo, Japan
- Department of Bioengineering, School of Engineering, the University of Tokyo, Hongo Bunkyo-ku, Tokyo, Japan
| | - Kosuke Nagae
- Corporate R&D Headquarters, Konica Minolta, Inc., Hino-shi, Tokyo, Japan
| | - Yukito Nakamura
- Corporate R&D Headquarters, Konica Minolta, Inc., Hino-shi, Tokyo, Japan
| | - Kohei Tsumoto
- Institute of Medical Science, the University of Tokyo, Tokyo, Japan
- Department of Bioengineering, School of Engineering, the University of Tokyo, Hongo Bunkyo-ku, Tokyo, Japan
- * E-mail: (TK); (KT)
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3
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Bhandari D, Chen FC, Hamal S, Bridgman RC. Kinetic Analysis and Epitope Mapping of Monoclonal Antibodies to Salmonella Typhimurium Flagellin Using a Surface Plasmon Resonance Biosensor. Antibodies (Basel) 2019; 8:antib8010022. [PMID: 31544828 PMCID: PMC6640700 DOI: 10.3390/antib8010022] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 02/28/2019] [Accepted: 03/02/2019] [Indexed: 11/23/2022] Open
Abstract
Salmonella Typhimurium is one of the leading causes of foodborne diseases worldwide. Biosensors and immunoassays utilizing monoclonal antibodies are widely used for the detection and subtyping of S. Typhimurium. However, due to insufficient information on the nature of binding with S. Typhimurium flagellin, the selection of appropriate antibodies for assay development is a cumbersome task. Hence, we aimed to compare the binding kinetics of a panel of monoclonal antibodies and their relative binding sites to flagellin antigen using a surface plasmon resonance biosensor. Initially, the flagellin was captured on the sensor surface through an immobilized anti-flagellin antibody. The interactions of different concentrations of monoclonal antibodies to flagellin were determined, and binding curves were fitted using 1:1 bio-interaction model to calculate the kinetic parameters. For epitope mapping, pairwise comparisons were completed to determine the binding inhibition of each paired combination of monoclonal antibodies. It was found that these monoclonal antibodies differed significantly (p < 0.05) in association rate, dissociation rate, and equilibrium dissociation constants. Of the five monoclonal antibodies, only two interfered with the binding of each other. Four distinct epitopes located within a 23 kDa domain of flagellin were identified. Findings from this study provide crucial information needed for the further development and optimization of biosensors and other immunoassays for the detection and subtyping of Salmonella.
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Affiliation(s)
- Devendra Bhandari
- Department of Agricultural and Environmental Sciences, Tennessee State University, Nashville, TN 37209, USA.
| | - Fur-Chi Chen
- Department of Human Sciences, Tennessee State University, Nashville, TN 37209, USA.
| | - Shreya Hamal
- Department of Agricultural and Environmental Sciences, Tennessee State University, Nashville, TN 37209, USA.
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4
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Thomsen L, Gurevich L. A surface plasmon resonance assay for characterisation and epitope mapping of anti-GLP-1 antibodies. J Mol Recognit 2018; 31:e2711. [PMID: 29671912 DOI: 10.1002/jmr.2711] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 01/28/2018] [Accepted: 02/19/2018] [Indexed: 11/07/2022]
Abstract
The incretin hormone glucagon-like peptide-1 (GLP-1) has been subject to substantial pharmaceutical research regarding the treatment of type 2 diabetes mellitus. However, quantification of GLP-1 levels remains complicated due to the low circulation concentration and concurrent existence of numerous metabolites, homologous peptides, and potentially introduced GLP-1 receptor agonists. Surface plasmon resonance (SPR) facilitates real-time monitoring allowing a more detailed characterisation of the interaction compared with conventional enzyme-linked immunosorbent assays (ELISA). In this paper, we describe the development of the first SPR assays for characterisation of anti-GLP-1 antibodies for ELISA purposes. Binding responses were obtained on covalently immobilised anti-GLP-1 antibodies at 12°C, 25°C, and 40°C and fitted to a biomolecular (1:1) interaction model showing association rates of 1.01 × 103 to 4.54 × 103 M-1 s-1 and dissociation rates of 3.56 × 10-5 to 1.56 × 10-3 s-1 leading to affinities of 35.2 to 344 nM, depending on the temperature. Determination of thermodynamic properties revealed an enthalpy driven interaction (ΔH < ΔS < 0) with higher affinities at lower temperatures due to the formation and stabilisation of hydrogen bonds within the binding site primarily composed of polar amino acids (ΔCp < 0). Pair-wise epitope mapping was performed on captured anti-GLP-1 antibodies followed by subsequent interaction with GLP-1 (7-36) and other anti-GLP-1 antibodies. A global evaluation of every binding response led to an epitope map elucidating the potential of various anti-GLP-1 antibody pairs for sandwich ELISA and hence pinpointing the optimal antibody combinations. The SPR assays proved capable of providing vital information for ELISA development endorsing it as a useful optimisation tool.
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Affiliation(s)
- Lasse Thomsen
- Institute of Physics and Nanotechnology, Aalborg University, 9220, Aalborg Ø, Denmark
| | - Leonid Gurevich
- Institute of Physics and Nanotechnology, Aalborg University, 9220, Aalborg Ø, Denmark
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Ali MA, Tabassum S, Wang Q, Wang Y, Kumar R, Dong L. Integrated dual-modality microfluidic sensor for biomarker detection using lithographic plasmonic crystal. LAB ON A CHIP 2018; 18:803-817. [PMID: 29431801 DOI: 10.1039/c7lc01211j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This paper reports an integrated dual-modality microfluidic sensor chip, consisting of a patterned periodic array of nanoposts coated with gold (Au) and graphene oxide (GO), to detect target biomarker molecules in a limited sample volume. The device generates both electrochemical and surface plasmon resonance (SPR) signals from a single sensing area of Au-GO nanoposts. The Au-GO nanoposts are functionalized with specific receptor molecules, serving as a spatially well-defined nanostructured working electrode for electrochemical sensing, as well as a nanostructured plasmonic crystal for SPR-based sensing via the excitation of surface plasmon polaritons. High sensitivity of the electrochemical measurement originates from the presence of the nanoposts on the surface of the working electrode where radial diffusion of redox species occurs. Complementarily, the SPR detection allows convenient tracking of dynamic antigen-antibody interactions, to describe the association and dissociation phases occurring at the sensor surface. The soft-lithographically formed nanoposts provide high reproducibility of the sensor response to epidermal growth factor receptor (ErbB2) molecules even at a femtomolar level. Sensitivities of the electrochemical measurements to ErbB2 are found to be 20.47 μA μM-1 cm-2 in a range from 1 fM to 0.1 μM, and those of the SPR measurements to be 1.35 nm μM-1 in a range from 10 pM to 1 nM, and 0.80 nm μM-1 in a range from 1 nM to 0.1 μM. The integrated dual-modality sensor offers higher sensitivity (through higher surface area and diffusions from nanoposts for electrochemical measurements), as well as the dynamic measurements of antigen-antibody bindings (through the SPR measurement), while operating simultaneously in a same sensing area using the same sample volume.
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Affiliation(s)
- Md Azahar Ali
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011, USA.
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6
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Athmaram T, Saraswat S, Sikarwar B, Verma SK, Singh AK, Boopathi M. Characterization of pandemic influenza A (H1N1) virus hemagglutinin specific polyclonal antibodies for biosensor applications. J Med Virol 2013; 86:363-71. [DOI: 10.1002/jmv.23753] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2013] [Indexed: 11/06/2022]
Affiliation(s)
- T.N. Athmaram
- Defence Research and Development Establishment; Ministry of Defence; Gwalior MP India
| | - Shweta Saraswat
- Defence Research and Development Establishment; Ministry of Defence; Gwalior MP India
| | - Bhavna Sikarwar
- Defence Research and Development Establishment; Ministry of Defence; Gwalior MP India
| | | | - Anil K. Singh
- Defence Research and Development Establishment; Ministry of Defence; Gwalior MP India
| | - M. Boopathi
- Defence Research and Development Establishment; Ministry of Defence; Gwalior MP India
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7
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Kemper M, Spridon D, van IJzendoorn LJ, Prins MWJ. Interactions between protein coated particles and polymer surfaces studied with the rotating particles probe. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:8149-8155. [PMID: 22571333 DOI: 10.1021/la300630n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Nonspecific interactions between proteins and polymer surfaces have to be minimized in order to control the performance of biosensors based on immunoassays with particle labels. In this paper we investigate these nonspecific interactions by analyzing the response of protein coated magnetic particles to a rotating magnetic field while the particles are in nanometer vicinity to a polymer surface. We use the fraction of nonrotating (bound) particles as a probe for the interaction between the particles and the surface. As a model system, we study the interaction of myoglobin coated particles with oxidized polystyrene surfaces. We measure the interaction as a function of the ionic strength of the solution, varying the oxidation time of the polystyrene and the pH of the solution. To describe the data we propose a model in which particles bind to the polymer by crossing an energy barrier. The height of this barrier depends on the ionic strength of the solution and two interaction parameters. The fraction of nonrotating particles as a function of ionic strength shows a characteristic shape that can be explained with a normal distribution of energy barrier heights. This method to determine interaction parameters paves the way for further studies to quantify the roles of protein coated particles and polymers in their mutual nonspecific interactions in different matrixes.
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Affiliation(s)
- M Kemper
- Eindhoven University of Technology, Eindhoven, The Netherlands.
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8
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Comparison of techniques to screen and characterize bacteria-specific hybridomas for high-quality monoclonal antibodies selection. Anal Biochem 2011; 421:26-36. [PMID: 22033288 DOI: 10.1016/j.ab.2011.10.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 09/28/2011] [Accepted: 10/02/2011] [Indexed: 11/22/2022]
Abstract
Antibodies are very important materials for diagnostics. A rapid and simple hybridoma screening method will help in delivering specific monoclonal antibodies. In this study, we systematically developed the first antibody array to screen for bacteria-specific monoclonal antibodies using Listeria monocytogenes as a bacteria model. The antibody array was developed to expedite the hybridoma screening process by printing hybridoma supernatants on a glass slide coated with an antigen of interest. This screening method is based on the binding ability of supernatants to the coated antigen. The bound supernatants were detected by a fluorescently labeled anti-mouse immunoglobulin. Conditions (slide types, coating, spotting, and blocking buffers) for antibody array construction were optimized. To demonstrate its usefulness, antibody array was used to screen a sample set of 96 hybridoma supernatants in comparison to ELISA. Most of the positive results identified by ELISA and antibody array methods were in agreement except for those with low signals that were undetectable by antibody array. Hybridoma supernatants were further characterized with surface plasmon resonance to obtain additional data on the characteristics of each selected clone. While the antibody array was slightly less sensitive than ELISA, a much faster and lower cost procedure to screen clones against multiple antigens has been demonstrated.
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9
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Helwa R, Hoheisel JD. Analysis of DNA–protein interactions: from nitrocellulose filter binding assays to microarray studies. Anal Bioanal Chem 2010; 398:2551-61. [DOI: 10.1007/s00216-010-4096-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 08/03/2010] [Indexed: 10/19/2022]
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10
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Patel R, Andrien BA. Kinetic analysis of a monoclonal therapeutic antibody and its single-chain homolog by surface plasmon resonance. Anal Biochem 2010; 396:59-68. [DOI: 10.1016/j.ab.2009.08.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 08/26/2009] [Accepted: 08/27/2009] [Indexed: 10/20/2022]
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11
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Gunnarsson K. Affinity-based biosensors for biomolecular interaction analysis. ACTA ACUST UNITED AC 2008; Chapter 18:Unit 18.6. [PMID: 18432748 DOI: 10.1002/0471142735.im1806s33] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This overview presents an introduction to affinity-based biosensors, most notably the BIACORE. These biosensors detect molecular interactions by immobilizing one of the interactants (the ligand or target molecule) on the surface of a sensor chip. A solution containing the other interactant is then applied to the chip. Binding of analyte to the surface results in a response proportional to the mass bound. A discussion of sensor chips and practical applications is also provided.
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Characterization of antibody–antigen interactions: Comparison between surface plasmon resonance measurements and high-mass matrix-assisted laser desorption/ionization mass spectrometry. Anal Biochem 2008; 375:35-45. [DOI: 10.1016/j.ab.2007.11.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Accepted: 11/12/2007] [Indexed: 11/20/2022]
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14
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Wang L, Cole KD, Peterson A, He HJ, Gaigalas AK, Zong Y. Monoclonal Antibody Selection for Interleukin-4 Quantification Using Suspension Arrays and Forward-Phase Protein Microarrays. J Proteome Res 2007; 6:4720-7. [DOI: 10.1021/pr070535s] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- L. Wang
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312
| | - K. D. Cole
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312
| | - A. Peterson
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312
| | - Hua-Jun He
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312
| | - A. K. Gaigalas
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312
| | - Y. Zong
- Full Moon BioSystems, Inc., 754 North Pastoria Avenue, Sunnyvale, California 94085
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15
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Boghaert ER, Khandke KM, Sridharan L, Dougher M, DiJoseph JF, Kunz A, Hamann PR, Moran J, Chaudhary I, Damle NK. Determination of pharmacokinetic values of calicheamicin-antibody conjugates in mice by plasmon resonance analysis of small (5 microl) blood samples. Cancer Chemother Pharmacol 2007; 61:1027-35. [PMID: 17668210 DOI: 10.1007/s00280-007-0560-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Accepted: 07/10/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE The present study aims to establish a method that provides fast, precise and reproducible pharmacokinetic (PK) parameters of antibody-calicheamicin conjugates. The method should discriminate between PK of the antibody moiety and PK of the conjugated calicheamicin (CM). METHODS The conjugates gemtuzumab ozogamicin (CMA-676, Mylotarg) or inotuzumab ozogamicin (CMC-544) were injected in the tail vein of nude mice. At regular time intervals, 5 mul whole blood samples were taken from the tail artery. Concentrations of conjugated CMA-676 or CMC-544 as well as concentrations of their respective antibody moiety were determined by sandwich plasmon resonance. This detection system measures changes in the plasma resonance angle caused by the interaction of macromolecules on biosensor chips. We determined as a first measure the binding of CMA-676 or CMC-544 to their respective antigens, CD33 or CD22. As a second measure we determined the amount of CM on the antigen-bound conjugates. This was done by determination of changes in plasma resonance angle after binding of an anti-CM antibody. RESULTS Sandwich plasmon resonance allowed detection of both conjugates in blood of mice in a range of 100-1,000 ng/ml protein. Due to the precision of the sampling and detection methods, PK values of each conjugate were determined in individual mice. Calicheamicin bound to antibody was eliminated faster than the antibody alone. The presence of a CD22-expressing tumour in mice reduced the plasma levels of the CD22-targeting conjugate but not of the CD33-targeting one. CONCLUSIONS Using small blood samples from a mouse, the sandwich plasmon resonance method provided PK-values of CM-conjugates and information about the stability of the linkage in vivo. Comparison between the PK-values of CM-conjugates in tumour-bearing and tumour-free mice suggested that retention of the conjugate in tumour tissue due to antigen targeting could be deduced from the plasma levels.
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MESH Headings
- Aminoglycosides/administration & dosage
- Aminoglycosides/blood
- Aminoglycosides/pharmacokinetics
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/blood
- Antibodies, Monoclonal/pharmacokinetics
- Antibodies, Monoclonal, Humanized
- Area Under Curve
- Cell Line, Tumor
- Gemtuzumab
- Half-Life
- Humans
- Injections, Intraperitoneal
- Injections, Intravenous
- Inotuzumab Ozogamicin
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Rabbits
- Surface Plasmon Resonance
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Affiliation(s)
- Erwin R Boghaert
- Wyeth Discovery Research (Oncology), 401 North Middletown Rd, Pearl River, NY 10965, USA
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Nagata S, Numata Y, Onda M, Ise T, Hahn Y, Lee B, Pastan I. Rapid grouping of monoclonal antibodies based on their topographical epitopes by a label-free competitive immunoassay. J Immunol Methods 2004; 292:141-55. [PMID: 15350519 DOI: 10.1016/j.jim.2004.06.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 06/10/2004] [Accepted: 06/15/2004] [Indexed: 11/22/2022]
Abstract
Topography of epitopes of monoclonal antibodies (MAbs), identified as the mutual competition of the MAbs, can be valuable indicators for the biological functions of MAbs. However, the determination of topographical epitopes is not performed before the functional screening of MAbs, because the requirement for purifying and labeling of MAbs makes the mapping experiment difficult, particularly in the early stage of MAb production. Here we describe a new label-free competitive enzyme-linked immunosorbent assay (LFC-ELISA) for the rapid grouping of MAbs based on the topography of their epitopes. In the LFC-ELISA, the immune complex formed by a competitor, MAb#2, and an antigen is challenged by an indicator, MAb#1 that had been captured on the ELISA plate through a secondary antibody. The MAb#2-antigen immune complex is trapped by MAb#1 only if MAb#1 reacts with an epitope different from that of MAb#2. The immune complex (MAb#2-antigen-MAb#1) is detected with an enzyme-labeled reagent specific to a tag on the antigen. Our experiments using different anti-CD30 MAbs and a CD30-Fc fusion protein as the antigen revealed that the LFC-ELISA performed well with MAbs of different isotypes (IgG1, IgG2a, and IgG2b), and in a practical range of MAb concentrations (0.3-10 microg/ml) and affinities (0.9-13 nM of Kd). We obtained pairwise competition data from all 26 anti-CD30 MAbs. We then utilized a cluster analysis and a bootstrap method to analyze the competition data for grouping of the MAbs. This objective and automated analysis identified eight distinct topographical epitopes on CD30. The reactivity of the anti-CD30 MAbs in immunoblot, and their inhibiting activity on CD30-CD30-ligand binding correlated with the topographical epitopes. The results show that the LFC-ELISA combined with cluster analysis is a useful new method for grouping MAbs based on their topographical epitopes and can be used in the early stage of MAb production. One useful application is to identify MAbs reacting with different epitopes from a large number of MAbs so that the most appropriate MAbs can be selected for therapeutic use.
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Affiliation(s)
- Satoshi Nagata
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 5106, Bethesda, MD 20892-4264, USA
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Abstract
Biosensors are analytical devices composed of a recognition element of biological origin and a physico-chemical transducer. The biological element is capable of sensing the presence, activity or concentration of a chemical analyte in solution. The sensing takes place either as a binding event or a biocatalytical event. These interactions produce a measurable change in a solution property, which the transducer converts into a quantifiable electrical signal. Present-day applications of biosensors to clinical chemistry are reviewed, including basic and applied research, commercial applications and fabrication techniques. Recognition elements include enzymes as biocatalytic recognition elements and immunoagents and DNA segments as affinity ligand recognition elements, coupled to electrochemical and optical modes of transduction. The future will include biosensors based on synthetic recognition elements to allow broad applicability to different classes of analytes and modes of transduction extending lower limits of sensitivity. Microfabrication will permit biosensors to be constructed as arrays and incorporated into lab-on-a-chip devices.
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Affiliation(s)
- Paul D'Orazio
- Instrumentation Laboratory, 101 Hartwell Avenue, Lexington MA 02421, USA.
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18
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Kröger K, Bauer J, Fleckenstein B, Rademann J, Jung G, Gauglitz G. Epitope-mapping of transglutaminase with parallel label-free optical detection. Biosens Bioelectron 2002; 17:937-44. [PMID: 12392942 DOI: 10.1016/s0956-5663(02)00085-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The gastrointestinal disorder coeliac disease (CD) is induced by the ingestion of wheat gluten and is characterized by damage of the typical structure of the intestinal mucosa. The enzyme tissue transglutaminase (tTGase) was identified as the major target of disease-specific antibodies in-patients. We performed an epitope fine-mapping with a series of pentadecapeptides synthesized using parallel multiple peptide synthesis. For the detection of biomolecular interactions a label-free parallel method, reflectometric interference spectroscopy (RIfS), was used. This is the first optical label-free method adapted to a high throughput screening (HTS) format and the experimental results demonstrate its applicability as a biological screening device. A high titer of anti-tTGase antibodies is found in the serum of coeliac patients. We have taken the first step towards a fast non-surgical test for the detection of these antibodies. In order to identify and characterize a continuous epitope with high affinity against the anti-tTGase antibody a screening of 21 pentadecapeptides has been accomplished with the parallel RIfS system. A single channel RIfS-system with high resolution was used to determine binding constants of identified peptides with high affinity.
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Affiliation(s)
- K Kröger
- Institute of Physical and Theoretical Chemistry, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
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Gambari R. Biospecific interaction analysis: a tool for drug discovery and development. AMERICAN JOURNAL OF PHARMACOGENOMICS : GENOMICS-RELATED RESEARCH IN DRUG DEVELOPMENT AND CLINICAL PRACTICE 2002; 1:119-35. [PMID: 12174673 DOI: 10.2165/00129785-200101020-00005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The recent development of surface plasmon resonance (SPR)-based biosensor technologies for biospecific interaction analysis (BIA) enables the monitoring of a variety of molecular reactions in real-time. The biomolecular interactions occur at the surface of a flow cell of a sensor chip between a ligand immobilized on the surface and an injected analyte. SPR-based BIA offers many advantages over most of the other methodologies available for the study of biomolecular interactions, including full automation, no requirement for labeling, and the availability of a large variety of activated sensor chips that allow immobilization of DNA, RNA, proteins, peptides and cells. The assay is rapid and requires only small quantitities of both ligand and analyte in order to obtain informative results. In addition, the sensor chip can be re-used many times, leading to low running costs. Aside from the analysis of all possible combinations of peptide, protein, DNA and RNA interactions, this technology can also be used for screening of monoclonal antibodies and epitope mapping, analysis of interactions between low molecular weight compounds and proteins or nucleic acids, interactions between cells and ligands, and real-time monitoring of gene expression. Applications of SPR-based BIA in medicine include the molecular diagnosis of viral infections and genetic diseases caused by point mutations. Future perspectives include the combinations of SPR-based BIA with mass spectrometry, the use of biosensors in proteomics, and the application of this technology to design and develop efficient drug delivery systems.
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Affiliation(s)
- R Gambari
- Department of Biochemistry and Molecular Biology, and Biotechnology Center, Ferrara University, Ferrara, Italy.
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UDA T, INOUE K, NISHIMURA T, HIFUMI E, SHIMIZU K, EGASHIRA N. Simultaneous Detection of Two Antigens by Surface Plasmon Resonance Sensor. ELECTROCHEMISTRY 2001. [DOI: 10.5796/electrochemistry.69.976] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Taizo UDA
- School of Biosciences, Hiroshima Prefectural University
| | | | | | - Emi HIFUMI
- School of Biosciences, Hiroshima Prefectural University
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Natsume T, Nakayama H, Isobe T. BIA-MS-MS: biomolecular interaction analysis for functional proteomics. Trends Biotechnol 2001; 19:S28-33. [PMID: 11780967 DOI: 10.1016/s0167-7799(01)01797-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
One of the experimental processes of functional proteomics is the analysis of protein interaction. Here, we review a new analytical platform, BIA-MS, for protein interaction analysis. BIA-MS is an integration of a surface plasmon resonance biosensor for real-time interaction analysis and mass spectrometry for the subsequent identification of interacting molecules.
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Affiliation(s)
- T Natsume
- National Institute of Advanced Science and Technology, Biological Information Research Center (JBIRC), Tokyo, Japan.
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Abstract
The FLAG (Sigma, St. Louis, MO, USA) peptide is a frequently used hydrophilic and immunogenic fusion tag which was specifically designed to facilitate rapid purification by immunoaffinity chromatography. The monoclonal antibody M1 recognizes the free N-terminus of the peptide tag in a calcium dependent manner. Dissociation of the complex can be performed by the addition of chelating agents such as EDTA. This effect can be exploited for immunoaffinity purification of FLAG-tagged fusion proteins. Kinetic information obtained from monitoring interactions in real-time measurement (Biacore 2000) using surface plasmon resonance as detection principle did not show any difference for association and dissociation rate constants in the presence (k(a) = 3.03 x 10(3) M(-1) k(d) = 1.25 x 10(-3) s(-1)) and in the absence of Ca2+ (k(a) = 3.59 x 10(3) M(-1) s(-1), k(d) = 1.16 x 10(-3) s(-1)). These findings corroborate the reports from Mol. Immunol. 33 (1996) 601-608 describing similar binding analyzed by enzyme-linked immunosorbent assay experiments. These investigations are in contrast to the observations in immunoaffinity chromatography with immobilized anti-FLAG antibody M1.
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Affiliation(s)
- A Einhauer
- Institute of Applied Microbiology, University of Agricultural Sciences, Vienna, Austria
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Uchimura T, Nakano K, Hashiguchi T, Iwamoto H, Miura K, Yoshimura Y, Hanyu N, Hirata K, Imakuma M, Motomiya Y, Maruyama I. Elevation of N-(carboxymethyl)valine residue in hemoglobin of diabetic patients. Its role in the development of diabetic nephropathy. Diabetes Care 2001; 24:891-6. [PMID: 11347750 DOI: 10.2337/diacare.24.5.891] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Advanced glycation end products (AGEs) are a risk factor for diabetic complications. We have developed an assay method for N-(carboxymethyl)valine (CMV) of the hemoglobin (CMV-Hb), which is an AGE generated from HbA1c. Herein we describe the clinical utility of CMV-Hb measurement for the diagnosis of diabetic nephropathy RESEARCH DESIGN AND METHODS BALB/c mice were immunized with carboxy-methylated Hb and monoclonal antibody raised against CMV-Hb. This antibody was characterized by a surface plasmon resonance. We developed a latex immunoassay using the antibody and measured CMV-Hb from erythrocytes in type 2 diabetic patients and healthy control subjects (age 64.6 +/- 12.0 vs. 61.1 +/- 13.2 years, NS: HbA1c 69 +/- 1.5 vs. 5.2 +/- 0.4%, P < 0.0001). RESULTS A monoclonal antibody against CMV-Hb beta-chain NH2-terminal and an assay method for measurement for CNMV-Hb were both developed in our laboratory. CMV-Hb levels were significantly greater in the diabetic patients than in the control subjects (18.2 +/- 6.9 vs. 12.7 +/- 0.9 pmol CMV/mg Hb, P < 0.0001). No correlation was found between CMV-Hb and HbA1c or CMV-Hb and glycated albumin. Levels of CMV-Hb increased as the diabetic nephropathy progressed. CONCLUSIONS We established an assay method for CMV-Hb and confirmed the presence of CMV-Hb in circulating erythrocytes. CMV-Hb was more prevalent in diabetic patients than in healthy subjects. Furthermore, it was significantly higher in patients with diabetic nephropathy, suggesting that the presence of CMV-Hb may be a valuable marker for the progression of diabetic nephropathy.
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Affiliation(s)
- T Uchimura
- Department of Laboratory and Molecular Medicine, Kagoshima University School of Medicine, Kagoshima City, Japan
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Green RJ, Frazier RA, Shakesheff KM, Davies MC, Roberts CJ, Tendler SJ. Surface plasmon resonance analysis of dynamic biological interactions with biomaterials. Biomaterials 2000; 21:1823-35. [PMID: 10919686 DOI: 10.1016/s0142-9612(00)00077-6] [Citation(s) in RCA: 412] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Surface plasmon resonance (SPR) is an optical technique that is widely gaining recognition as a valuable tool to investigate biological interactions. SPR offers real time in situ analysis of dynamic surface events and, thus, is capable of defining rates of adsorption and desorption for a range of surface interactions. In this review we highlight the diversity of SPR analysis. Examples of a wide range of applications of SPR are presented, concentrating on work relevant to the analysis of biomaterials. Particular emphasis is given to the use of SPR as a complimentary tool, showing the broad range of techniques that are routinely used alongside SPR analysis.
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Affiliation(s)
- R J Green
- Laboratory of Biophysics and Surface Analysis, School of Pharmaceutical Sciences, The University of Nottingham, University Park, UK.
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Natsume T, Nakayama H, Jansson O, Isobe T, Takio K, Mikoshiba K. Combination of biomolecular interaction analysis and mass spectrometric amino acid sequencing. Anal Chem 2000; 72:4193-8. [PMID: 10994983 DOI: 10.1021/ac000167a] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We describe an approach for the combination of biomolecular interaction analysis (BIA) and electrospray tandem mass spectrometry (ESI/MS/MS) to obtain sequence information on the affinity-bound proteins on the sensor chip of BIA. The procedure is illustrated with stable and unstable interactions of recombinant proteins, i.e., histidine-tagged protein-Ni2+/NTA and 1,4,5-inositol trisphosphate receptor-ligand interactions. The E. coli lysates expressing the recombinant proteins were passed through the sensor chips, and biomolecular interactions were monitored in real time. The molecules detected on the sensor chip were digested by delivering proteolytic enzyme to the sensing flow cells. The resulting on-chip digested peptide mixture at the mid- to low-femtomole level was recovered on a microcapillary reversed-phase precolumn by an on-line system and analyzed using HPLC-MS/MS. In both cases, unambiguous sequence information on the recombinant proteins isolated on the sensor chip was obtained from only a single run of analysis. The combined BIA-MS/MS may prove to be a general and versatile system to discover novel biomolecular interactions and to analyze protein complexes.
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Affiliation(s)
- T Natsume
- Calciosignal Net Project, Exploratory Research for Advanced Technology, JST, RIKEN Komagome Branch, Tokyo, Japan.
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Lyon LA, Peña DJ, Natan MJ. Surface Plasmon Resonance of Au Colloid-Modified Au Films: Particle Size Dependence. J Phys Chem B 1999. [DOI: 10.1021/jp984739v] [Citation(s) in RCA: 180] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Quinn J, Patel P, Fitzpatrick B, Manning B, Dillon P, Daly S, Okennedy R, Alcocer M, Lee H, Morgan M, Lang K. The use of regenerable, affinity ligand-based surfaces for immunosensor applications. Biosens Bioelectron 1999; 14:587-95. [PMID: 11459104 DOI: 10.1016/s0956-5663(99)00032-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The regeneration of antibody-binding surfaces is of major importance for re-usable sensor formats such as required for direct 'real-time' biosensing technologies and is often difficult to achieve. Antibodies commonly bind the antigen with high avidity and may themselves be sensitive to regeneration conditions. The interaction of polyclonal anti-chlorpyriphos antibody with an immobilised chlorpyriphos-ovalbumin (chlor-oval) conjugate and the interaction of soluble recombinant CD4 with covalently immobilised anti-CD4 IgG are presented in order to highlight these difficulties. Affinity-capture is suggested as an alternative format as it facilitates surface regeneration, directed immobilisation and the attainment of interaction progress curves that conform to the ideal pseudo-first-order kinetic interaction model. Protein A, protein G and polyclonal anti-mouse Fe-coated surfaces were used to observe the interaction of captured anti-GST monoclonal antibody with glutathione-s-transferase (GST). It was shown that a protein A affinity-capture surface produced ideal interaction progress curves while both protein G and polyclonal anti-mouse Fe resulted in systemic deviations.
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Affiliation(s)
- J Quinn
- School of Biotechnology, Dublin City University, Glasnevin, Ireland
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29
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Kröger D, Hucho F, Vogel H. Ligand Binding to Nicotinic Acetylcholine Receptor Investigated by Surface Plasmon Resonance. Anal Chem 1999; 71:3157-65. [DOI: 10.1021/ac9814391] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dietmar Kröger
- Laboratoire de Chimie Physique des Polymères et Membranes, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland, and Institut für Biochemie, Freie Universität Berlin, Thielallee 63, D-14195 Berlin
| | - Ferdinand Hucho
- Laboratoire de Chimie Physique des Polymères et Membranes, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland, and Institut für Biochemie, Freie Universität Berlin, Thielallee 63, D-14195 Berlin
| | - Horst Vogel
- Laboratoire de Chimie Physique des Polymères et Membranes, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland, and Institut für Biochemie, Freie Universität Berlin, Thielallee 63, D-14195 Berlin
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Lee JW, Kim KM, Jung SH, Lee KJ, Choi EC, Sung YC, Kang CY. Identification of a domain containing B-cell epitopes in hepatitis C virus E2 glycoprotein by using mouse monoclonal antibodies. J Virol 1999; 73:11-8. [PMID: 9847301 PMCID: PMC103802 DOI: 10.1128/jvi.73.1.11-18.1999] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Evidence from clinical and experimental studies of human and chimpanzees suggests that hepatitis C virus (HCV) envelope glycoprotein E2 is a key antigen for developing a vaccine against HCV infection. To identify B-cell epitopes in HCV E2, six murine monoclonal antibodies (MAbs), CET-1 to -6, specific for HCV E2 protein were generated by using recombinant proteins containing E2t (a C-terminally truncated domain of HCV E2 [amino acids 386 to 693] fused to human growth hormone and glycoprotein D). We tested whether HCV-infected sera were able to inhibit the binding of CET MAbs to the former fusion protein. Inhibitory activity was observed in most sera tested, which indicated that CET-1 to -6 were similar to anti-E2 antibodies in human sera with respect to the epitope specificity. The spacial relationship of epitopes on E2 recognized by CET MAbs was determined by surface plasmon resonance analysis and competitive enzyme-linked immunosorbent assay. The data indicated that three overlapping epitopes were recognized by CET-1 to -6. For mapping the epitopes recognized by CET MAbs, we analyzed the reactivities of CET MAbs to six truncated forms and two chimeric forms of recombinant E2 proteins. The data suggest that the epitopes recognized by CET-1 to -6 are located in a small domain of E2 spanning amino acid residues 528 to 546.
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Affiliation(s)
- J W Lee
- Laboratory of Immunology, College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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31
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Abstract
Surface plasmon resonance (SPR) biosensing using colloidal Au enhancement is reported. Immobilization of approximately 11-nm-diameter colloidal Au to an evaporated Au film results in a large shift in plasmon angle, a broadened plasmon resonance, and an increase in minimum reflectance. The incorporation of colloidal Au into SPR biosensing results in increased SPR sensitivity to protein-protein interactions when a Au film-immobilized antibody and an antigen-colloidal Au conjugate comprise the binding pair. A highly specific particle-enhanced analogue of a sandwich immunoassay is also demonstrated by complexing the Au particle to a secondary antibody. A tremendous signal amplification is observed, as addition of the antibody-Au colloid conjugate results in a 25-fold larger signal than that due to addition of a free antibody solution that is 6 orders of magnitude more concentrated. Picomolar detection of human immunoglobulin G has been realized using particle enhancement, with the theoretical limits for the technique being much lower. Finally, a quasi-linear relationship between particle coverage and plasmon angle shift is presented, thereby providing for a direct correlation between plasmon shift and solution antigen concentration. Together, these results represent significant advances in the generality and sensitivity of SPR as it is applied to biosensing.
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Affiliation(s)
- L A Lyon
- Department of Chemistry, Pennsylvania State University, University Park 16802, USA
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Pearson JE, Kane JW, Petraki-Kallioti I, Gill A, Vadgama P. Surface plasmon resonance: a study of the effect of biotinylation on the selection of antibodies for use in immunoassays. J Immunol Methods 1998; 221:87-94. [PMID: 9894900 DOI: 10.1016/s0022-1759(98)00167-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Surface plasmon resonance is a valuable optical phenomenon for monitoring biomolecular interactions in real time. In this project anti-mouse-Fc was coupled to the carboxymethyl dextran coating on the surface of a CM5 sensor chip (BIAcore) using amine coupling. Monoclonal antibodies (MAbs) to Luteinizing Hormone (LH) were then captured on this surface in the correct orientation for binding. LH (500 IU/l) was injected over the surface and the subsequent binding and dissociation events were monitored. The resulting optical response curves allowed fast analysis of the binding interactions of eight selected MAbs. It was possible to develop a two-site immunometric assay for LH using a pair of these MAbs. The effect of biotinylating the MAbs, using various biotin:antibody coupling ratios, on their subsequent binding to both LH and avidin conjugated alkaline phosphatase was also investigated. This approach has allowed rapid evaluation of the effect of changes in both reagent and reaction conditions on immunoassay performance and appears to be a valuable adjunct to immunosensor and immunoassay development.
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Affiliation(s)
- J E Pearson
- Department of Medicine (Clinical Biochemistry), University of Manchester, Hope Hospital, Salford, UK
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Bracewell DG, Gill A, Hoare M, Lowe PA, Maule CH. An optical biosensor for real-time chromatography monitoring: breakthrough determination. Biosens Bioelectron 1998; 13:847-53. [PMID: 9828381 DOI: 10.1016/s0956-5663(98)00051-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The use of an optical biosensor for immunorecognition of protein products during affinity chromatography is discussed to provide rapid data describing the loading and subsequent breakthrough, followed by elution and fraction collection. The optical biosensor works by following in real-time the interaction of soluble ligate with an appropriate ligand attached to the optically active surface. The initial rate of interaction between soluble ligate and immobilized ligand has been shown to correlate well with ligate concentration. This method of analysis has also been shown to agree well with ELISA, the traditionally employed technique for immunoassay of protein products lacking, for example, catalytic activity. Forward prediction, using models of the breakthrough fitted to the real-time data, has enabled the column saturation point to be determined before it has been reached, thus enabling appropriate action to ensure minimal loss of protein product while improving column utilization efficiency. The biosensor, operated within a flow injection analysis regime, has been demonstrated to provide concentration data within 10 s, with a total assay turnaround of 30 s.
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Affiliation(s)
- D G Bracewell
- Department of Biochemical Engineering, University College London, UK
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Affiliation(s)
- G E Morris
- MRC Biotechnology Group, NE Wales Institute, Deeside Clwyd, UK
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McCall AM, Amoroso AR, Sautès C, Marks JD, Weiner LM. Characterization of anti-mouse Fc gamma RII single-chain Fv fragments derived from human phage display libraries. IMMUNOTECHNOLOGY : AN INTERNATIONAL JOURNAL OF IMMUNOLOGICAL ENGINEERING 1998; 4:71-87. [PMID: 9661816 DOI: 10.1016/s1380-2933(98)00006-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Few antibodies are available to study the function of the Fc gamma RII murine immunoglobulin receptor. Human phage display libraries represent a potential source of single-chain Fv (sFv) to facilitate the study of the Fc gamma RII murine immunoglobulin receptor. OBJECTIVES To isolate human sFv specific for mouse Fc gamma RII. STUDY DESIGN Two human phage display libraries were selected for reactivity to mouse Fc gamma RII. Those human anti-mouse Fc gamma RII sFv that were derived from the libraries were characterized with respect to kinetics, cellular binding, epitope specificity and amino acid sequence. RESULTS Nine anti-mouse Fc gamma RII sFv molecules were isolated from two human phage display libraries (Marks et al., J Mol Biol 1991;222:581-597; Sheets et al., Proc Natl Acad Sci USA, in press). Surface plasmon resonance (SPR) analysis revealed that the human anti-mouse Fc gamma RII sFv had off-rates ranging from 10(-2) to 10(-3) s-1, with KD values calculated to range between 10(-7) and 10(-9) M. The binding of the FITC-labeled human anti-mouse Fc gamma RII sFv to mouse peritoneal neutrophils was not detected by flow cytometry, due to the rapid off-rates of these monomeric proteins. However, when the human anti-mouse Fc gamma RII sFv were coated on yellow-green latex particles, all of the human sFv were found to specifically bind to mouse peritoneal neutrophils. Deglycosylation of mouse Fc gamma RII did not diminish the binding of these sFv, suggesting that the sFv molecules recognize a polypeptide epitope on murine Fc gamma RII. In contrast, denaturation of mouse Fc gamma RII dramatically reduced the binding of the human sFv, suggesting that the epitopes are conformational. Sequence analysis of the human anti-mouse Fc gamma RII sFv revealed a high degree of structural similarity among the nine sFv. The DP73 VH gene segment was utilized by four of the nine sFv, while seven of the nine sFv contained the DPL16 V lambda gene segment. The sequence similarities between these sFv suggested that several of the human sFv may recognize a common epitope on mouse Fc gamma RII. Epitope mapping studies demonstrated that eight of the nine human anti-mouse Fc gamma RII sFv recognized overlapping epitopes. All of these human anti-mouse Fc gamma RII sFv competed with the 2.4G2 rat monoclonal anti-mouse Fc gamma RII/III antibody for binding with mouse Fc gamma RII, suggesting that the targeted epitopes reside in or near the Fc binding pocket of mouse Fc gamma RII. CONCLUSIONS The availability of novel sFv recognizing mouse Fc gamma RII will facilitate the study of receptor triggering events. Such sFv may prove useful to engage murine Fc gamma RII for targeted cytotoxicity or immunization strategies.
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Affiliation(s)
- A M McCall
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
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36
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Abstract
An epitope may be defined as a specific site on an antigen module characterized by the binding of one monoclonal antibody (MAb). Epitope mapping by surface plasmon resonance in the BIAcore biosensor may be performed to characterize an antigen or a group of specific MAbs or both. This article describes the BIAcore instrument and methods for such mapping. Examples include molecular interaction studies with simple and complex proteins, such as myoglobin and calprotectin, respectively.
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Affiliation(s)
- B Johne
- Nycomed Pharma AS, Oslo, Norway
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Seipelt I, Hoffmann SH, Schmidt J, Engels JW, Beckers T. Overexpression, purification, and use of a soluble human interleukin-4 receptor alpha-chain/Ig gamma 1 fusion protein for ligand binding studies. Characterization of ligand binding to soluble IL-4 receptor alpha-chain by surface plasmon resonance measurements and by microtiter-plate-based ELISA with biotinylated IL-4. Biochem Biophys Res Commun 1997; 239:534-42. [PMID: 9344865 DOI: 10.1006/bbrc.1997.7509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The pleiotropic cytokine IL-4 transmits cellular signals mainly via the IL-4 receptor complex, with the alpha-chain as the high affinity binding subunit. Here we describe the overexpression of a soluble IL-4R alpha-chain (sIL-4R) as a fusion to immunoglobulin gamma 1 heavy chain, consisting of the H-CH2-CH3 domains, in baby hamster kidney cells. The dimeric fusion protein named sIL-4R:E gamma 1 was purified from culture supernatant by protein-A affinity chromatography, yielding up to 10 mg/l homogenous protein which was highly stable. The antibody-like features of the sIL-4R:E gamma 1 fusion protein allowed immobilization on a biosensor matrix for surface plasmon resonance measurements by direct amine coupling as well as immobilization on microtiter plates coated with protein A for displacement binding. Kinetic parameters (kon and koff) for binding of IL-4 or the antagonistic mutant IL-4(Y124D) to the sIL-4R:E gamma 1 fusion protein on the chip as determined with the BIAcore instrument showed a high affinity binding with KD = 239 +/- 35 pM and KD=148 +/- 33 pM, respectively. The extremely high kon rate and the relatively slow koff rate for both ligands highlighted the limits of the BIAcore technology. The binding affinity as calculated in displacement binding studies with biotinylated IL-4 was similar for IL-4 and IL-4(Y124D) (IC50=1.1nM), thus offering a simple alternative for initial characterization of IL-4 mutants.
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Affiliation(s)
- I Seipelt
- Department of Cancer Research, ASTA Medica AG, Frankfurt/Main, Germany
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Van Regenmortel MH, Altschuh D, Chatellier J, Rauffer-Bruyère N, Richalet-Sécordel P, Saunal H. Uses of biosensors in the study of viral antigens. Immunol Invest 1997; 26:67-82. [PMID: 9037613 DOI: 10.3109/08820139709048916] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The introduction in 1990 of a new biosensor technology based on surface plasmon resonance has greatly simplified the measurement of binding interactions in biology. This new technology known as biomolecular interaction analysis makes it possible to visualize the binding process as a function of time by following the increase in refractive index that occurs when one of the interacting partners binds to its ligand immobilized on the surface of a sensor chip. None of the reactants needs to be labelled, which avoids the artefactual changes in binding properties that often result when the molecules are labelled. Biosensor instruments are well-suited for the rapid mapping of viral epitopes and for identifying which combinations of capturing and detector Mabs will give the best results in sandwich assays. Biosensor binding data are also useful for selecting peptides to be used in diagnostic solid-phase immunoassays. Very small changes in binding affinity can be measured with considerable precision which is a prerequisite for analyzing the functional effect and thermodynamic implications of limited structural changes in interacting molecules. On-rate (ka) and off-rate (kd) kinetic constants of the interaction between virus and antibody can be readily measured and the equilibrium affinity constant K can be calculated from the ratio ka/kd = K.
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Affiliation(s)
- M H Van Regenmortel
- Immunochemistry Department, CNRS, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
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Levieux D, Levieux A. Antigenic specificity of monoclonal antibodies to beef myoglobin determined by cross-reactivity studies against myoglobins from domestic species. Meat Sci 1996; 42:239-49. [DOI: 10.1016/0309-1740(95)00056-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/1995] [Revised: 09/04/1995] [Accepted: 09/18/1995] [Indexed: 10/18/2022]
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41
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Schuck P. Kinetics of ligand binding to receptor immobilized in a polymer matrix, as detected with an evanescent wave biosensor. I. A computer simulation of the influence of mass transport. Biophys J 1996; 70:1230-49. [PMID: 8785280 PMCID: PMC1225050 DOI: 10.1016/s0006-3495(96)79681-9] [Citation(s) in RCA: 193] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The influence of mass transport on ligand binding to receptor immobilized in a polymer matrix, as detected with an evanescent wave biosensor, was investigated. A one-dimensional computer model for the mass transport of ligand between the bulk solution and the polymer gel and within the gel was employed, and the influence of the diffusion coefficient, the partition coefficient, the thickness of the matrix, and the distribution of immobilized receptor were studied for a variety of conditions. Under conditions that may apply to many published experimental studies, diffusion within the matrix was found to decrease the overall ligand transport significantly. For relatively slow reactions, small spatial gradients of free and bound ligand in the gel are found, whereas for relatively rapid reactions strong inhomogeneities of ligand within the gel occur before establishment of equilibrium. Several types of deviations from ideal pseudo-first-order binding progress curves are described that resemble those of published experimental data. Extremely transport limited reactions can in some cases be fitted with apparently ideal binding progress curves, although with apparent reaction rates that are much lower than the true reaction rates. Nevertheless, the ratio of the apparent rate constants can be semiquantitatively consistent with the true equilibrium constant. Apparently "cooperative" binding can result from high chemical on rates at high receptor saturation. Dissociation in the presence of transport limitation was found to be well described empirically by a single or a double exponential, with both apparent rate constants considerably lower than the intrinsic chemical rate constant. Transport limitations in the gel can introduce many generally unknown factors into the binding progress curve. The simulations suggest that unexpected deviations from ideal binding progress curves may be due to highly transport influenced binding kinetics. The use of a thinner polymer matrix could significantly increase the range of detectable rate constants.
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Affiliation(s)
- P Schuck
- Laboratory of Biochemical Pharmacology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institute of Health, Bethesda, Maryland 20892, USA.
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42
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Browning JL, Miatkowski K, Sizing I, Griffiths D, Zafari M, Benjamin CD, Meier W, Mackay F. Signaling through the lymphotoxin beta receptor induces the death of some adenocarcinoma tumor lines. J Exp Med 1996; 183:867-78. [PMID: 8642291 PMCID: PMC2192357 DOI: 10.1084/jem.183.3.867] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Surface lymphotoxin (LT) is a heteromeric complex of LT-alpha and LT-beta chains that binds to the LT-beta receptor (LT-beta-R), a member of the tumor necrosis factor (TNF) family of receptors. The biological function of this receptor-ligand system is poorly characterized. Since signaling through other members of this receptor family can induce cell death, e.g., the TNF and Fas receptors, it is important to determine if similar signaling events can be communicated via the LT-beta-R. A soluble form of the surface complex was produced by coexpression of LT-alpha and a converted form of LT-beta wherein the normally type II LT-beta membrane protein was changed to a type I secreted form. Recombinant LT-alpha 1/beta 2 was cytotoxic to the human adenocarcinoma cell lines HT-29, WiDr, MDA-MB-468, and HT-3 when added with the synergizing agent interferon (IFN) gamma. When immobilized on a plastic surface, anti-LT-beta-R monoclonal antibodies (mAbs) induced the death of these cells, demonstrating direct signaling via the LT-beta-R. Anti-LT-beta-R mAbs were also identified that inhibited ligand-induced cell death, whereas others were found to potentiate the activity of the ligand when added in solution. The human WiDr adenocarcinoma line forms solid tumors in immunocompromised mice, and treatment with an anti-LT-beta-R antibody combined with human IFN-gamma arrested tumor growth. The delineation of a biological signaling event mediated by the LT-beta-R opens a window for further studies on its immunological role, and furthermore, activation of the LT-beta-R may have an application in tumor therapy.
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Affiliation(s)
- J L Browning
- Department of Immunology and Inflammation, Biogen, Cambridge, Massachusetts 02142, USA
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43
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Malmborg AC, Johansson K, Sigvardsson M, Borrebaeck CA, Leanderson T. Real-time analysis of Oct protein-octamer interaction and transcription complex assembly. Mol Immunol 1995; 32:1429-42. [PMID: 8643112 DOI: 10.1016/0161-5890(95)00067-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Specific interactions between the protein-binding sequence of the immunoglobulin transcription regulatory element, the octamer, and Oct proteins have been investigated using a biosensor based on surface plasmon resonance. By analysis of in vitro translated Oct1 and Oct2A with a consensus octamer probe, it was shown that the affinity constant, association rate constant and dissociation rate constant of Oct1 were higher than for Oct2A. The biggest difference was in the association rate constants, but this difference was reduced when an octamer motif containing a point mutation was used as a probe. Elements in the octamer flanking sequence could increase the on-rate of Oct proteins to a mutated octamer while not decreasing the off-rate. Oct-octamer interaction in whole nuclear extracts could be detected readily in the biosensor and adapter interactions with template bound proteins were revealed. Thus, biosensor analysis represent a fast and convenient alternative approach to study specific protein-DNA and protein-protein interactions in analysis of transcriptional regulation.
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Affiliation(s)
- A C Malmborg
- Department of Immunotechnology, Lund University, Sweden
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44
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Levieux D, Venien A, Levieux A. Epitopic analysis and quantification of bovine myoglobin with monoclonal antibodies. Hybridoma (Larchmt) 1995; 14:435-42. [PMID: 8575792 DOI: 10.1089/hyb.1995.14.435] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Seven rat monoclonal antibodies (MAb) for bovine myoglobin were produced. Five antibodies reacted with surface-absorbed myoglobin whereas the two remainders reacted only in a sandwich type ELISA. The ability of different antibodies to bind simultaneously to myoglobin was examined by competition and additivity experiments and three noncompeting epitope regions were found. A two-site enzyme immunoassay was developed and allowed quantification of 30 ng/ml bovine myoglobin. These antibodies should be valuable tools in comparative studies for immunological reactivity of mammalian myoglobins and for myoglobin measurement in serum and urine of myopathic animals.
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Affiliation(s)
- D Levieux
- INRA, Meat Research Station, Immunochemistry Unit, Theix, Saint-Genès Champanelle, France
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45
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Abstract
The BIAcore biosensor provides a simple and rapid approach for analysing recombinant antibodies and phage displayed antibody libraries. In this review we describe the application of the biosensor in the screening of recombinant antibody fragments, kinetic selection of phage displayed antibodies, characterization and epitope mapping of monoclonal antibodies and their fragments.
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Affiliation(s)
- A C Malmborg
- Department of Immunotechnology, Lund University, Sweden
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46
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Johne B, Hansen K, Mørk E, Holtlund J. Colloidal gold conjugated monoclonal antibodies, studied in the BIAcore biosensor and in the Nycocard immunoassay format. J Immunol Methods 1995; 183:167-74. [PMID: 7602134 DOI: 10.1016/0022-1759(95)00047-e] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Interactions between immobilized capture monoclonal antibodies (mAbs), analyte molecules and colloidal gold conjugated second monoclonal antibodies have been investigated in the BIAcore biosensor and in the Nycocard immunoassay format. This report focuses on six monoclonal antibodies against human heart myoglobin, although, results with other antigens are also discussed. The BIAcore was used to screen monoclonal antibodies as antigen capture reagents, and for their function as colloidal gold conjugated second antibodies in the Nycocard. Some antibodies with low affinity caused by a rapid antigen dissociation rate, showed high affinity kinetics when used unlabelled or as gold conjugated detector reagents. One gold conjugated mAb with excellent properties in the Nycocard, showed double binding to one epitope, when tested in the BIAcore. The real time visualization of association and dissociation rates was a unique tool in the elucidation of antigen-antibody interactions. Our study confirmed that good antibody candidates selected with the BIAcore must always be tested in their actual conjugation situation before final optimization.
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Affiliation(s)
- B Johne
- Nycomed Pharma AS, Oslo, Norway
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47
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Yang WP, Wu H, Barbas CF. Surface plasmon resonance based kinetic studies of zinc finger-DNA interactions. J Immunol Methods 1995; 183:175-82. [PMID: 7602135 DOI: 10.1016/0022-1759(95)00048-f] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Libraries of the zinc finger DNA binding protein, Zif268, have been constructed and selected for affinity and specificity toward DNA targets using the phage display technique (Wu et al., 1995). Mutant proteins were purified to homogeneity and were characterized for their ability to interact with their DNA targets using a real-time biomolecular interaction assay (BIA). One mutant protein, C7, bound the Zif268 consensus binding sequence with a 13-fold increase in affinity as compared to the wild-type Zif268 protein. Mutant proteins with moderate affinity for new DNA targets within a consensus sequence of HIV-1 have also been obtained. Surface plasmon resonance based BIA has provided invaluable kinetic information which offers insights into the mechanism of protein-DNA interactions.
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Affiliation(s)
- W P Yang
- Department of Molecular Biology, Scripps Research Institute, La Jolla, CA 92037, USA
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48
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Hutchinson AM. Evanescent wave biosensors. Real-time analysis of biomolecular interactions. Mol Biotechnol 1995; 3:47-54. [PMID: 7606504 DOI: 10.1007/bf02821334] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Optical biosensors, based on evanescent wave technology, are analytical devices that measure the interactions between biomolecules in real time, without the need for any labels. Specific ligands are immobilized to a sensor surface, and a solution of receptor or antibody is injected over the top. Binding is measured by recording changes in the refractive index, caused by the molecules interacting near the sensor surface within the evanescent field. Evanescent wave-based biosensors are being used to study an increasing number of applications in the life sciences, including the binding and dissociation kinetics of antibodies and receptor-ligand pairs, protein-DNA and DNA-DNA interactions, epitope mapping, phage display libraries, and whole cell- and virus-protein interactions. There are currently four commercially available evanescent wave biosensors on the market. This article describes the technology behind their sensing techniques, as well as the range of applications in which they are employed.
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Affiliation(s)
- A M Hutchinson
- Department of Natural Products, Glaxo Research and Development Ltd., Greenford, Middlesex, UK
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49
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Fisher RJ, Fivash M. Surface plasmon resonance based methods for measuring the kinetics and binding affinities of biomolecular interactions. Curr Opin Biotechnol 1994; 5:389-95. [PMID: 7765171 DOI: 10.1016/0958-1669(94)90047-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Surface plasmon resonance is emerging as the method of choice to study biomolecular interactions between macromolecules because it allows the observation of real-time kinetics for these processes. The method is currently being applied to the study of antigen-antibody interactions, protein-DNA interactions, receptor SH2 domain-phosphotyrosine peptide interactions and receptor-ligand interactions.
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Affiliation(s)
- R J Fisher
- Laboratory of Cellular Biochemistry, PRI/DynCorp, NCI-Frederick Cancer Research and Development Center, Maryland 21702-1201
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50
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Gruen LC, McKimm-Breschkin JL, Caldwell JB, Nice EC. Affinity ranking of influenza neuraminidase mutants with monoclonal antibodies using an optical biosensor. Comparison with ELISA and slot blot assays. J Immunol Methods 1994; 168:91-100. [PMID: 8288899 DOI: 10.1016/0022-1759(94)90213-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A recently developed alternative to the more traditional techniques for studying antigen-antibody interactions has been examined. This method involves the use of an optical biosensor employing surface plasmon resonance detection. In this system one of the reactants is immobilized on the sensor surface and other reactants are passed over the sensor surface sequentially at a constant flow rate. Binding phenomena are detected in real time from changes in the angle at which surface plasmon resonance occurs. This is dependent, among other things, on changes in the refractive index (which is directly proportional to the mass) at or near to the sensor surface. Applications of this biosensor technique for comparing the binding of related neuraminidases, purified from escape mutants of influenza virus NWS/G70C/75 (N9), to two antibody Fab fragments, are described. These results were compared with those obtained from ELISA and slot blot assays on the same neuraminidases interacting with the same two monoclonal antibodies. The biosensor method was shown to be highly specific, permitting rapid screening of binding in such antigen-antibody systems.
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Affiliation(s)
- L C Gruen
- CSIRO Division of Biomolecular Engineering, Parkville, Victoria, Australia
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