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Krieg D, Winter G, Svilenov HL. It is never too late for a cocktail - Development and analytical characterization of fixed-dose antibody combinations. J Pharm Sci 2022; 111:2149-2157. [DOI: 10.1016/j.xphs.2022.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/13/2022] [Accepted: 05/13/2022] [Indexed: 11/24/2022]
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2
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Berger P, Sturgeon C. Pregnancy testing with hCG--future prospects. Trends Endocrinol Metab 2014; 25:637-48. [PMID: 25246381 DOI: 10.1016/j.tem.2014.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 08/08/2014] [Accepted: 08/08/2014] [Indexed: 12/29/2022]
Abstract
Pregnancy tests for human chorionic gonadotrophin (hCG) are used widely in hospital and home settings. Assays measuring hCG also have uses in prenatal screening and oncology. The output from three recent international workshops provides a framework for reliable measurement of hCG. Requirements for future hCG assays include use of clear descriptive nomenclature, informed selection of antibodies of well-defined epitope specificities, and design of robust methods. Tests will be precisely characterized and calibrated in SI units using six International Reference Reagents (IRR) for hCG and variants, and the Fifth International Standard for hCG 07/364, making it possible to report clinical results in molar units. These measures will help to increase patient safety by reducing the risk of erroneous or misleading hCG results.
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Affiliation(s)
- Peter Berger
- Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A6020 Innsbruck, Austria.
| | - Catharine Sturgeon
- UK NEQAS for Peptide Hormones, Department of Laboratory Medicine, Royal Infirmary, Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, UK.
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3
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Peng L, Damschroder MM, Wu H, Dall’Acqua WF. Bi-epitope SPR surfaces: a solution to develop robust immunoassays. PLoS One 2014; 9:e112070. [PMID: 25372291 PMCID: PMC4221230 DOI: 10.1371/journal.pone.0112070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 10/10/2014] [Indexed: 11/18/2022] Open
Abstract
Surface plasmon resonance (SPR)-based immunoassays have numerous applications and require high affinity reagents for sensitive and reliable measurements. We describe a quick approach to turn low affinity antibodies into appropriate capture reagents. We used antibodies recognizing human ephrin type A receptor 2 (EphA2) and a ProteOn XPR36 as a model system. We generated so-called 'bi-epitope' sensor surfaces by immobilizing various pairs of anti-EphA2 antibodies using standard amine coupling. The apparent binding affinities to EphA2 and EphA2 detection sensitivities of the bi-epitope and 'single-epitope' surfaces were then compared. For all antibody pairs tested, bi-epitope surfaces exhibited an ∼ 10-100-fold improvement in apparent binding affinities when compared with single-epitope ones. When pairing 2 antibodies of low intrinsic binding affinities (∼ 10(-8) M) and fast dissociation rates (∼ 10(-2) s(-1)), the apparent binding affinity and dissociation rate of the bi-epitope surface was improved up to ∼ 10(-10) M and 10(-4) s(-1), respectively. This led to an ∼ 100-200-fold enhancement in EphA2 limit of detection in crude cell supernatants. Our results show that the use of antibody mixtures in SPR applications constitutes a powerful approach to develop sensitive immunoassays, as previously shown for non-SPR formats. As SPR-based assays have significantly expanded their reach in the last decade, such an approach promises to further accelerate their development.
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Affiliation(s)
- Li Peng
- Department of Antibody Discovery and Protein Engineering, MedImmune, One MedImmune Way, Gaithersburg, MD, 20878, United States of America
| | - Melissa M. Damschroder
- Department of Antibody Discovery and Protein Engineering, MedImmune, One MedImmune Way, Gaithersburg, MD, 20878, United States of America
| | - Herren Wu
- Department of Antibody Discovery and Protein Engineering, MedImmune, One MedImmune Way, Gaithersburg, MD, 20878, United States of America
| | - William F. Dall’Acqua
- Department of Antibody Discovery and Protein Engineering, MedImmune, One MedImmune Way, Gaithersburg, MD, 20878, United States of America
- * E-mail:
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4
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Dmitriev AD, Tarakanova JN, Yakovleva DA, Dmitriev DA, Phartooshnaya OV, Kolyaskina GI, Massino YS, Borisova OV, Segal OL, Smirnova MB, Ulanova TI, Lavrov VF. Monoclonal antibodies requiring coating buffer with low pH for efficient antigen capture in sandwich ELISA: the rarities or practically important phenomena? J Immunoassay Immunochem 2014; 34:414-37. [PMID: 23859792 DOI: 10.1080/15321819.2013.764894] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
This article reexamines some opinions concerning pH requirements for optimal immobilization of monoclonal antibodies (mAbs) by passive adsorption in antigen capture ELISA. It was discovered that substitution of "classical" sodium phosphate (pH 7.5) and carbonate (pH 9.5) coating solutions by acid (pH 2.8) buffers maximized antigen capture 4 out of 10 different tested anti-HBsAg mAbs, resulting in a 1.5-2.5 increase of binding curve coefficients. By measuring both mAbs amounts and functionality, the enhancement effect was attributed to the better preservation of solid phase antibodies activity.
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Affiliation(s)
- Alexander D Dmitriev
- Mechnikov Research Institute of Vaccines and Sera, RAMS, O. Andzhaparidze Virology Unit, Moscow, Russia.
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5
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Berger P, Paus E, Hemken PM, Sturgeon C, Stewart WW, Skinner JP, Harwick LC, Saldana SC, Ramsay CS, Rupprecht KR, Olsen KH, Bidart JM, Stenman UH. Candidate epitopes for measurement of hCG and related molecules: the second ISOBM TD-7 workshop. Tumour Biol 2013; 34:4033-57. [PMID: 24068570 PMCID: PMC3858614 DOI: 10.1007/s13277-013-0994-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 07/01/2013] [Indexed: 11/29/2022] Open
Abstract
Participants of the Second International Workshop (WS) on human chorionic gonadotropin (hCG) of the International Society of Oncology and Biomarkers Tissue Differentiation 7 (ISOBM TD-7) have characterized in detail a panel of 69 antibodies (Abs) directed against hCG and hCG-related variants that were submitted by eight companies and research groups. Specificities of the Abs were determined using the First WHO International Reference Reagents for six hCG variants, i.e., hCG, hCGn, hCGβ, hCGβn, hCGβcf, and hCGα, which are calibrated in SI units, and hLH. Molecular epitope localizations were assigned to the ISOBM-mAbs by comparing ISOBM-Ab specificity, sandwich compatibility, and mutual inhibition profiles, to those of 17 reference monoclonal (m)Abs of known molecular epitope specificities. It appeared that 48 Abs recognized hCGβ-, 8 hCGα-, and 13 αβ-heterodimer-specific epitopes. Twenty-seven mAbs were of pan hCG specificity, two thereof with no (<0.1 %; epitope β1), 12 with low (<1.0 %; epitopes β2/4), and 13 with high (>>1 %; epitopes β3/5) hLH cross-reactivity. The majority of hCGβ epitopes recognized were located in two major antigenic domains, one on the peptide chain of the tips of β-sheet loops 1 and 3 (epitopes β2–6; 27 mAbs) and the second around the cystine knot (e.g., epitopes β1, β7, and β10; 9 mAbs). Four mAbs recognized epitopes on hCGβcf-only (e.g., epitopes β11 and β13) and six mAbs epitopes on the remote hCGβ-carboxyl-terminal peptide (epitopes β8 and β9 corresponding to amino acids 135–144 and 111–116, respectively). For routine diagnostic measurements, methods are used that either detect hCG-only, hCGβ-only, or hCG together with hCGβ or hCG together with hCGβ and hCGβcf. Sandwich assays that measure hCG plus hCGβ and eventually hCGβcf should recognize the protein backbone of the analytes preferably on an equimolar basis, should not cross-react with hLH and not be susceptible to blunting of signal by nonmeasured variants like hCGβcf. Such assays can be constructed using pairs of mAbs directed against the cystine knot-associated epitope β1 (Asp10, Asp60, and Gln89) in combination with epitopes β2 or β4 located at the top of β-sheet loops 1 + 3 of hCGβ involving aa hCGβ20-25 + 68-77. In summary, the results of the First and Second ISOBM TD-7 WSs on hCG provide the basis for harmonization of specificities and epitopes of mAbs to be used in multifunctional and selective diagnostic hCG methods for different clinical purposes.
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Affiliation(s)
- P Berger
- Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A6020, Innsbruck, Austria,
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6
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Trilling AK, Harmsen MM, Ruigrok VJ, Zuilhof H, Beekwilder J. The effect of uniform capture molecule orientation on biosensor sensitivity: Dependence on analyte properties. Biosens Bioelectron 2013; 40:219-26. [DOI: 10.1016/j.bios.2012.07.027] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 06/28/2012] [Accepted: 07/13/2012] [Indexed: 01/25/2023]
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7
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Guo SL, Chen PC, Chen MS, Cheng YC, Lin JM, Lee HC, Chen CS. A fast universal immobilization of immunoglobulin G at 4 °C for the development of array-based immunoassays. PLoS One 2012; 7:e51370. [PMID: 23236488 PMCID: PMC3517563 DOI: 10.1371/journal.pone.0051370] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 11/07/2012] [Indexed: 11/19/2022] Open
Abstract
To maintain the antibody activity and enhance performance of array-based immunoassays, protein G was used to allow a shorter duration of immunoglobulin G immobilization at 4 °C, with the antibody placed in the appropriate orientation. The multiplexed detection of six pain-related message molecules (PRMMs) was used as examples for the development of array-based immunoassays: substance P, calcitonin gene-related peptide, nerve growth factor, brain-derived neurotrophic factor, tumor necrosis factor-α, and β-endorphin. Protein G- and non-protein G-coated slides were tested. Compared to non-protein G immunoassays, protein G shortened the antibody immobilization time at 4 °C from overnight to 2 hours. Only protein G-facilitated immunoassays succeeded in simultaneously detecting all six PRMMs with high specificity. Dose-response curves showed that the limits of detection of the protein G-multiplexed immunoassays for the PRMMs was approximately 164, 167, 120, 60, 80, and 92 pg/ml, respectively. Thus, protein G effectively shortens the duration of antibody immobilization at 4 °C, allowing the use of sensitive array-based immunoassays for the simultaneous detection of PRMMs.
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Affiliation(s)
- Shu-Lin Guo
- Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
- Department of Anesthesiology, Cathay General Hospital, Taipei, Taiwan
| | - Po-Chung Chen
- Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
| | - Ming-Shuo Chen
- Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
| | - Yu-Che Cheng
- Department of Medical Research, Cathay General Hospital, Taipei, Taiwan
- Institute of Biomedical Engineering, National Central University, Jhongli, Taiwan
| | - Jun-Mu Lin
- Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
| | - Hoong-Chien Lee
- Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
- * E-mail: (HL); (CC)
| | - Chien-Sheng Chen
- Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jhongli, Taiwan
- * E-mail: (HL); (CC)
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8
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Norde W, Lyklema J. Interfacial behaviour of proteins, with special reference to immunoglobulins. A physicochemical study. Adv Colloid Interface Sci 2012; 179-182:5-13. [PMID: 22795486 DOI: 10.1016/j.cis.2012.06.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 05/23/2012] [Accepted: 06/25/2012] [Indexed: 10/28/2022]
Abstract
Some basic elements of the adsorption of proteins on solid surfaces are briefly reviewed, emphasizing immunoglobulins. The paper focuses on the physicochemical interactions and considers the precautions that have to be taken to let the protein adsorb in a way in which it is biologically active. Contributing factors include surface pretreatment, composition of the solution, (pH, nature and concentration of electrolytes, etc.), extent of reversibility, and lateral interactions in the adsorbed state. Particular attention is paid to the option of partially pre-coating the adsorbent by irreversibly adsorbed polymers to induce the later adsorbing immune globulin molecules to assume a biologically preferred orientation and conformation.
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9
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Huang J, Meyer C, Zhu C. T cell antigen recognition at the cell membrane. Mol Immunol 2012; 52:155-64. [PMID: 22683645 DOI: 10.1016/j.molimm.2012.05.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 04/27/2012] [Accepted: 05/01/2012] [Indexed: 11/16/2022]
Abstract
T cell antigen receptors (TCRs) on the surface of T cells bind specifically to particular peptide bound major histocompatibility complexes (pMHCs) presented on the surface of antigen presenting cells (APCs). This interaction is a key event in T cell antigen recognition and activation. Most studies have used surface plasmon resonance (SPR) to measure the in vitro binding kinetics of TCR-pMHC interactions in solution using purified proteins. However, these measurements are not physiologically precise, as both TCRs and pMHCs are membrane-associated molecules which are regulated by their cellular environments. Recently, single-molecule förster resonance energy transfer (FRET) and single-molecule mechanical assays were used to measure the in situ binding kinetics of TCR-pMHC interactions on the surface of live T cells. These studies have provided exciting insights into the biochemical basis of T cell antigen recognition and suggest that TCRs serially engage with a small number of antigens with very fast kinetics in order to maximize TCR signaling and sensitivity.
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Affiliation(s)
- Jun Huang
- Department of Microbiology & Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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10
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Wiseman ME, Frank CW. Antibody adsorption and orientation on hydrophobic surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:1765-74. [PMID: 22181558 DOI: 10.1021/la203095p] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The orientation of a monoclonal, anti-streptavidin human IgG1 antibody on a model hydrophobic, CH(3)-terminated surface (1-dodecanethiol self-assembled monolayer on gold) was studied by monitoring the mechanical coupling between the adsorbed layer and the surface as well as the binding of molecular probes to the antibodies. In this study, the streptavidin antigen was used as a probe for the Fab portions of the antibody, while bacteria-derived Protein G' was used as a probe for the Fc region. Bovine serum albumin (BSA) acted as a blocking protein. Monolayer coverage occurred around 468 ng/cm(2). Below 100 ng/cm(2), antibodies were found to adsorb flat-on, tightly coupled to the surface and unable to capture their antigen, whereas the Fc region was able to bind Protein G'. At half-monolayer coverage, there was a transition in the mechanism of adsorption to allow for vertically oriented antibodies, as evidenced by the binding of both Protein G' and streptavidin as well as looser mechanical coupling with the surface. Monolayer coverage was characterized by a reduced level in probe binding per antibody and an even less rigid coupling to the surface.
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Affiliation(s)
- Meredith E Wiseman
- Department of Chemical Engineering, Stanford University, 381 North-South Mall, Stauffer III, Stanford, California 94305-5025, United States
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11
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Koefoed K, Steinaa L, Søderberg JN, Kjær I, Jacobsen HJ, Meijer PJ, Haurum JS, Jensen A, Kragh M, Andersen PS, Pedersen MW. Rational identification of an optimal antibody mixture for targeting the epidermal growth factor receptor. MAbs 2011; 3:584-95. [PMID: 22123060 DOI: 10.4161/mabs.3.6.17955] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The epidermal growth factor receptor (EGFR) is frequently dysregulated in human malignancies and a validated target for cancer therapy. Two monoclonal anti-EGFR antibodies (cetuximab and panitumumab) are approved for clinical use. However, the percentage of patients responding to treatment is low and many patients experiencing an initial response eventually relapse. Thus, the need for more efficacious treatments remains. Previous studies have reported that mixtures of antibodies targeting multiple distinct epitopes are more effective than single mAbs at inhibiting growth of human cancer cells in vitro and in vivo. The current work describes the rational approach that led to discovery and selection of a novel anti-EGFR antibody mixture Sym004, which is currently in Phase 2 clinical testing. Twenty-four selected anti-EGFR antibodies were systematically tested in dual and triple mixtures for their ability to inhibit cancer cells in vitro and tumor growth in vivo. The results show that targeting EGFR dependent cancer cells with mixtures of antibodies is superior at inhibiting their growth both in vitro and in vivo. In particular, antibody mixtures targeting non-overlapping epitopes on domain III are efficient and indeed Sym004 is composed of two monoclonal antibodies targeting this domain. The superior growth inhibitory activity of mixtures correlated with their ability to induce efficient EGFR degradation.
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12
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Walker MR, Makropoulos DA, Achuthanandam R, Van Arsdell S, Bugelski PJ. Development of a human whole blood assay for prediction of cytokine release similar to anti-CD28 superagonists using multiplex cytokine and hierarchical cluster analysis. Int Immunopharmacol 2011; 11:1697-705. [PMID: 21689786 DOI: 10.1016/j.intimp.2011.06.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 06/01/2011] [Accepted: 06/02/2011] [Indexed: 01/23/2023]
Abstract
Anti-CD28 superagonist (SA) mediated cytokine release syndrome (CRS), an adverse event resulting in systemic release of cytokines, is an emergent issue in drug development. CRS is of potential concern for all monoclonal antibodies (mAbs) particularly those directed against cell surface targets on lymphocytes. Concern regarding patient safety requires development of novel methods to predict these adverse reactions. Due to the inability of animal studies to predict CRS, we have developed a whole blood in vitro screen to support First in Human studies and assess the potential for mAbs to cause anti-CD28 SA-like CRS. For this purpose we have immobilized marketed mAbs, whose potential for causing CRS and milder infusion reactions is known, on Protein A beads and used these beads to stimulate cytokine release. After culture, supernatants are harvested and frozen for later multiplex analysis of cytokines using Searchlight™ technology. We have employed hierarchicalluster analysis (HCA) to allow comparison of 12 different cytokine levels across numerous donors, treatments, and experiments. Results conclusively distinguish test mAb responses from an anti-CD28 superagonist mAb response. As part of a global analysis of preclinical data, the results of this assay can facilitate entry into First in Human clinical trials, help with selection of starting doses and may allow more rapid dose escalation using smaller cohorts.
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Affiliation(s)
- Mindi R Walker
- Biologics Toxicology, Center of Excellence in Biotechnology, Centocor R&D Inc., Radnor, PA 19087, United States.
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Hosse RJ, Tay L, Hattarki MK, Pontes-Braz L, Pearce LA, Nuttall SD, Dolezal O. Kinetic screening of antibody–Im7 conjugates by capture on a colicin E7 DNase domain using optical biosensors. Anal Biochem 2009; 385:346-57. [DOI: 10.1016/j.ab.2008.11.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Revised: 11/07/2008] [Accepted: 11/12/2008] [Indexed: 10/21/2022]
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14
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ter Meulen J, van den Brink EN, Poon LLM, Marissen WE, Leung CSW, Cox F, Cheung CY, Bakker AQ, Bogaards JA, van Deventer E, Preiser W, Doerr HW, Chow VT, de Kruif J, Peiris JSM, Goudsmit J. Human monoclonal antibody combination against SARS coronavirus: synergy and coverage of escape mutants. PLoS Med 2006; 3:e237. [PMID: 16796401 PMCID: PMC1483912 DOI: 10.1371/journal.pmed.0030237] [Citation(s) in RCA: 500] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Accepted: 04/03/2006] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Experimental animal data show that protection against severe acute respiratory syndrome coronavirus (SARS-CoV) infection with human monoclonal antibodies (mAbs) is feasible. For an effective immune prophylaxis in humans, broad coverage of different strains of SARS-CoV and control of potential neutralization escape variants will be required. Combinations of virus-neutralizing, noncompeting mAbs may have these properties. METHODS AND FINDINGS Human mAb CR3014 has been shown to completely prevent lung pathology and abolish pharyngeal shedding of SARS-CoV in infected ferrets. We generated in vitro SARS-CoV variants escaping neutralization by CR3014, which all had a single P462L mutation in the glycoprotein spike (S) of the escape virus. In vitro experiments confirmed that binding of CR3014 to a recombinant S fragment (amino acid residues 318-510) harboring this mutation was abolished. We therefore screened an antibody-phage library derived from blood of a convalescent SARS patient for antibodies complementary to CR3014. A novel mAb, CR3022, was identified that neutralized CR3014 escape viruses, did not compete with CR3014 for binding to recombinant S1 fragments, and bound to S1 fragments derived from the civet cat SARS-CoV-like strain SZ3. No escape variants could be generated with CR3022. The mixture of both mAbs showed neutralization of SARS-CoV in a synergistic fashion by recognizing different epitopes on the receptor-binding domain. Dose reduction indices of 4.5 and 20.5 were observed for CR3014 and CR3022, respectively, at 100% neutralization. Because enhancement of SARS-CoV infection by subneutralizing antibody concentrations is of concern, we show here that anti-SARS-CoV antibodies do not convert the abortive infection of primary human macrophages by SARS-CoV into a productive one. CONCLUSIONS The combination of two noncompeting human mAbs CR3014 and CR3022 potentially controls immune escape and extends the breadth of protection. At the same time, synergy between CR3014 and CR3022 may allow for a lower total antibody dose to be administered for passive immune prophylaxis of SARS-CoV infection.
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MESH Headings
- Amino Acid Substitution
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/therapeutic use
- Antibody Affinity
- Antibody Specificity
- Antigen-Antibody Reactions
- Antigenic Variation
- Antigens, Viral/immunology
- Base Sequence
- Binding Sites
- Cells, Cultured/virology
- Chlorocebus aethiops
- Disease Outbreaks
- Dose-Response Relationship, Immunologic
- Drug Synergism
- Epitopes/immunology
- Humans
- Immune Sera
- Immunization, Passive
- Immunoglobulin Heavy Chains/genetics
- Immunoglobulin Heavy Chains/immunology
- Immunoglobulin Light Chains/genetics
- Immunoglobulin Light Chains/immunology
- Immunoglobulin Variable Region/chemistry
- Immunoglobulin Variable Region/immunology
- Macrophages/virology
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Membrane Glycoproteins/physiology
- Molecular Sequence Data
- Mutation, Missense
- Nandiniidae/virology
- Neutralization Tests
- Point Mutation
- Protein Structure, Tertiary
- Recombinant Fusion Proteins/immunology
- Severe acute respiratory syndrome-related coronavirus/genetics
- Severe acute respiratory syndrome-related coronavirus/immunology
- Severe Acute Respiratory Syndrome/drug therapy
- Severe Acute Respiratory Syndrome/epidemiology
- Severe Acute Respiratory Syndrome/prevention & control
- Severe Acute Respiratory Syndrome/therapy
- Severe Acute Respiratory Syndrome/virology
- Spike Glycoprotein, Coronavirus
- Surface Plasmon Resonance
- Vero Cells
- Viral Envelope Proteins/genetics
- Viral Envelope Proteins/immunology
- Viral Envelope Proteins/physiology
- Virus Replication
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15
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Kelly LS, Kozak M, Walker T, Pierce M, Puett D. Lectin immunoassays using antibody fragments to detect glycoforms of human chorionic gonadotropin secreted by choriocarcinoma cells. Anal Biochem 2005; 338:253-62. [PMID: 15745745 DOI: 10.1016/j.ab.2004.12.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2004] [Indexed: 11/24/2022]
Abstract
Immobilized antibodies are commonly used to recognize and bind proteins of interest from heterogeneous samples; however, subsequent probing of the glycan(s) of captured glycoproteins with lectins is limited by interference due to the competing oligosaccharides inherently present on antibodies. To prepare capture antibodies with significantly reduced binding of any lectin, the glycosylated protein domains (F(c)) of two anti-human chorionic gonadotropin antibodies were proteolytically removed. Depending on the individual antibody, usable fragments were generated either directly or effectively separated after cleavage through partial reduction and thiol coupling to an appropriate matrix. Importantly, neither method required additional purification of the antibody fragments before immobilization. Binding of a variety of lectins to the functional fragments was reduced by approximately 90% compared with intact immunoglobulin G in both an enzyme-linked immunosorbent assay and a biosensor format. These carbohydrate-free antibody fragments were used to bind the glycoprotein hormone, human chorionic gonadotropin, produced during normal pregnancy and that secreted by three human choriocarcinoma cell lines. Lectins bound to the unpurified gonadotropin glycoforms in distinct patterns consistent with glycan structures previously elucidated by others on hormone samples purified from the urine of pregnant women and of patients with choriocarcinoma. The methods described in this article are applicable for generating capture reagents universally suitable for lectin immunoassays of glycoproteins.
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Affiliation(s)
- Lisa S Kelly
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
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16
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Barrett DA, Hartshome MS, Hussain MA, Shaw PN, Davies MC. Resistance to nonspecific protein adsorption by poly(vinyl alcohol) thin films adsorbed to a poly(styrene) support matrix studied using surface plasmon resonance. Anal Chem 2001; 73:5232-9. [PMID: 11721924 DOI: 10.1021/ac010368u] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thin films of poly(vinyl alcohol) (PVA) polymer were prepared on a flat, nonporous, poly(styrene) support matrix by adsorption from aqueous solution and were characterized in order to investigate the nonspecific adsorption of proteins to a chromatographically relevant surface. The integrity and surface coverage of the PVA thin films were established by surface analysis and atomic force microscopy imaging. The adsorption of the PVA polymers to the poly(styrene) substrate and the nonspecific adsorption of proteins to the PVA-coated surface were monitored using surface plasmon resonance. PVA was strongly bound to the poly(styrene) surface, but the surface density of the adsorbed PVA polymers was affected substantially by the concentration, molecular weight, and degree of hydrolysis of PVA polymers used. There was evidence of increasing degrees of unfolding of the PVA polymer onto the poly(styrene) surface as the concentration of the the PVA coating solution increased. Complete PVA coverage of the poly(styrene) surface was observed at PVA concentrations of 0.1 mg/mL or greater but with significant influence of both molecular weight and degree of hydrolysis of the PVA polymers. Resistance of the PVA-coated poly(styrene) surface to the nonspecific adsorption of human serum albumin (HSA) correlated with the degree of surface coverage of the PVA. The use of anti-HSA as a probe for adsorbed HSA suggested that HSA was displacing PVA from the poly(styrene) surface at the lower PVA surface coverage. A complete barrier to nonspecific protein adsorption was observed with a PVA coating solution concentration of greater than 0.1 mg/ mL with a degree of hydrolysis of <88%.
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Affiliation(s)
- D A Barrett
- School of Pharmaceutical Sciences, The University of Nottingham, UK.
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Chaudri ZN, Bartlet-Jones M, Panayotou G, Klonisch T, Roitt IM, Lund T, Delves PJ. Dual specificity antibodies using a double-stranded oligonucleotide bridge. FEBS Lett 1999; 450:23-6. [PMID: 10350050 DOI: 10.1016/s0014-5793(99)00466-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The covalent conjugation of oligonucleotides to antibody Fab' fragments was optimized by using oligonucleotides modified with a hexaethylene linker arm bearing three amino groups. One oligonucleotide was coupled to antibody of one specificity and a complementary oligonucleotide to antibody of a second specificity. The antibodies were then allowed to hybridize by base pairing of the complementary nucleotide sequences and the generation of bispecific antibody was analyzed on SDS-PAGE and confirmed using BIAcore analysis. The strategy of complementary oligonucleotide-linked bispecific molecules is not limited to antibodies but is applicable to linking any two molecules of different characteristics.
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Affiliation(s)
- Z N Chaudri
- Department of Immunology, University College London, The Windeyer Institute for Medical Sciences, UK
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