1
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Tulika T, Ruso-Julve F, Ahmadi S, Ljungars A, Rivera-de-Torre E, Wade J, Fernández-Quintero ML, Jenkins TP, Belfakir SB, Ross GMS, Boyens-Thiele L, Buell AK, Sakya SA, Sørensen CV, Bohn MF, Ledsgaard L, Voldborg BG, Francavilla C, Schlothauer T, Lomonte B, Andersen JT, Laustsen AH. Engineering of pH-dependent antigen binding properties for toxin-targeting IgG1 antibodies using light-chain shuffling. Structure 2024; 32:1404-1418.e7. [PMID: 39146931 DOI: 10.1016/j.str.2024.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 06/07/2024] [Accepted: 07/19/2024] [Indexed: 08/17/2024]
Abstract
Immunoglobulin G (IgG) antibodies that bind their cognate antigen in a pH-dependent manner (acid-switched antibodies) can release their bound antigen for degradation in the acidic environment of endosomes, while the IgGs are rescued by the neonatal Fc receptor (FcRn). Thus, such IgGs can neutralize multiple antigens over time and therefore be used at lower doses than their non-pH-responsive counterparts. Here, we show that light-chain shuffling combined with phage display technology can be used to discover IgG1 antibodies with increased pH-dependent antigen binding properties, using the snake venom toxins, myotoxin II and α-cobratoxin, as examples. We reveal differences in how the selected IgG1s engage their antigens and human FcRn and show how these differences translate into distinct cellular handling properties related to their pH-dependent antigen binding phenotypes and Fc-engineering for improved FcRn binding. Our study showcases the complexity of engineering pH-dependent antigen binding IgG1s and demonstrates the effects on cellular antibody-antigen recycling.
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Affiliation(s)
- Tulika Tulika
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Fulgencio Ruso-Julve
- Department of Pharmacology, University of Oslo, Oslo, Norway; Department of Immunology, Oslo University Hospital Rikshospitalet, Oslo, Norway; Precision Immunotherapy Alliance (PRIMA), University of Oslo, Oslo, Norway
| | - Shirin Ahmadi
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Anne Ljungars
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | | | - Jack Wade
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | | | - Timothy P Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Selma B Belfakir
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark; VenomAid Diagnostics ApS, Lyngby, Denmark
| | | | - Lars Boyens-Thiele
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Alexander K Buell
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Siri A Sakya
- Department of Pharmacology, University of Oslo, Oslo, Norway; Department of Immunology, Oslo University Hospital Rikshospitalet, Oslo, Norway; Precision Immunotherapy Alliance (PRIMA), University of Oslo, Oslo, Norway
| | - Christoffer V Sørensen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Markus-Frederik Bohn
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Line Ledsgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Bjørn G Voldborg
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Chiara Francavilla
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Tilman Schlothauer
- Roche Pharma Research and Early Development (pRED), Roche Innovation Center Munich, Penzberg, Germany
| | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiologia, Universidad de Costa Rica, San Jose, Costa Rica
| | - Jan Terje Andersen
- Department of Pharmacology, University of Oslo, Oslo, Norway; Department of Immunology, Oslo University Hospital Rikshospitalet, Oslo, Norway; Precision Immunotherapy Alliance (PRIMA), University of Oslo, Oslo, Norway.
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark.
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2
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Zhu N, Smallwood PM, Rattner A, Chang TH, Williams J, Wang Y, Nathans J. Utility of protein-protein binding surfaces composed of anti-parallel alpha-helices and beta-sheets selected by phage display. J Biol Chem 2024; 300:107283. [PMID: 38608728 PMCID: PMC11107207 DOI: 10.1016/j.jbc.2024.107283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 04/14/2024] Open
Abstract
Over the past 3 decades, a diverse collection of small protein domains have been used as scaffolds to generate general purpose protein-binding reagents using a variety of protein display and enrichment technologies. To expand the repertoire of scaffolds and protein surfaces that might serve this purpose, we have explored the utility of (i) a pair of anti-parallel alpha-helices in a small highly disulfide-bonded 4-helix bundle, the CC4 domain from reversion-inducing Cysteine-rich Protein with Kazal Motifs and (ii) a concave beta-sheet surface and two adjacent loops in the human FN3 domain, the scaffold for the widely used monobody platform. Using M13 phage display and next generation sequencing, we observe that, in both systems, libraries of ∼30 million variants contain binding proteins with affinities in the low μM range for baits corresponding to the extracellular domains of multiple mammalian proteins. CC4- and FN3-based binding proteins were fused to the N- and/or C-termini of Fc domains and used for immunostaining of transfected cells. Additionally, FN3-based binding proteins were inserted into VP1 of AAV to direct AAV infection to cells expressing a defined surface receptor. Finally, FN3-based binding proteins were inserted into the Pvc13 tail fiber protein of an extracellular contractile injection system particle to direct protein cargo delivery to cells expressing a defined surface receptor. These experiments support the utility of CC4 helices B and C and of FN3 beta-strands C, D, and F together with adjacent loops CD and FG as surfaces for engineering general purpose protein-binding reagents.
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Affiliation(s)
- Ningyu Zhu
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Philip M Smallwood
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Amir Rattner
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Tao-Hsin Chang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - John Williams
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Yanshu Wang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA.
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3
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Rivera‐de‐Torre E, Lampadariou S, Møiniche M, Bohn MF, Kazemi SM, Laustsen AH. Discovery of broadly-neutralizing antibodies against brown recluse spider and Gadim scorpion sphingomyelinases using consensus toxins as antigens. Protein Sci 2024; 33:e4901. [PMID: 38358130 PMCID: PMC10868436 DOI: 10.1002/pro.4901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 01/01/2024] [Accepted: 01/03/2024] [Indexed: 02/16/2024]
Abstract
Broadly-neutralizing monoclonal antibodies are becoming increasingly important tools for treating infectious diseases and animal envenomings. However, designing and developing broadly-neutralizing antibodies can be cumbersome using traditional low-throughput iterative protein engineering methods. Here, we present a new high-throughput approach for the standardized discovery of broadly-neutralizing monoclonal antibodies relying on phage display technology and consensus antigens representing average sequences of related proteins. We showcase the utility of this approach by applying it to toxic sphingomyelinases from the venoms of species from very distant orders of the animal kingdom, the recluse spider and Gadim scorpion. First, we designed a consensus sphingomyelinase and performed three rounds of phage display selection, followed by DELFIA-based screening and ranking, and benchmarked this to a similar campaign involving cross-panning against recombinant versions of the native toxins. Second, we identified two scFvs that not only bind the consensus toxins, but which can also neutralize sphingomyelinase activity of native whole venom in vitro. Finally, we conclude that the phage display campaign involving the use of the consensus toxin was more successful in yielding cross-neutralizing scFvs than the phage display campaign involving cross-panning.
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Affiliation(s)
| | - Stefanos Lampadariou
- Department of Biotechnology and BiomedicineTechnical University of DenmarkKongens LyngbyDenmark
| | - Mark Møiniche
- Department of Biotechnology and BiomedicineTechnical University of DenmarkKongens LyngbyDenmark
| | - Markus F. Bohn
- Department of Biotechnology and BiomedicineTechnical University of DenmarkKongens LyngbyDenmark
| | | | - Andreas H. Laustsen
- Department of Biotechnology and BiomedicineTechnical University of DenmarkKongens LyngbyDenmark
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4
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Sørensen CV, Fernández J, Adams AC, Wildenauer HHK, Schoffelen S, Ledsgaard L, Pucca MB, Fiebig M, Cerni FA, Tulika T, Voldborg BG, Karatt-Vellatt A, Morth JP, Ljungars A, Grav LM, Lomonte B, Laustsen AH. Antibody-dependent enhancement of toxicity of myotoxin II from Bothrops asper. Nat Commun 2024; 15:173. [PMID: 38228619 PMCID: PMC10791742 DOI: 10.1038/s41467-023-42624-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/17/2023] [Indexed: 01/18/2024] Open
Abstract
Improved therapies are needed against snakebite envenoming, which kills and permanently disables thousands of people each year. Recently developed neutralizing monoclonal antibodies against several snake toxins have shown promise in preclinical rodent models. Here, we use phage display technology to discover a human monoclonal antibody and show that this antibody causes antibody-dependent enhancement of toxicity (ADET) of myotoxin II from the venomous pit viper, Bothrops asper, in a mouse model of envenoming that mimics a snakebite. While clinical ADET related to snake venom has not yet been reported in humans, this report of ADET of a toxin from the animal kingdom highlights the necessity of assessing even well-known antibody formats in representative preclinical models to evaluate their therapeutic utility against toxins or venoms. This is essential to avoid potential deleterious effects as exemplified in the present study.
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Affiliation(s)
- Christoffer V Sørensen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Julián Fernández
- Instituto Clodomiro Picado, Facultad de Microbiologia, Universidad de Costa Rica, San Jose, Costa Rica
| | - Anna Christina Adams
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Helen H K Wildenauer
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Sanne Schoffelen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Line Ledsgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Manuela B Pucca
- Medical School, Federal University of Roraima, Boa Vista, BR-69310-000, Brazil
| | - Michael Fiebig
- Absolute Antibody Ltd, Wilton Centre, Redcar, Cleveland, TS10 4RF, UK
| | - Felipe A Cerni
- Postgraduate Program in Tropical Medicine, University of the State of Amazonas, Manaus, BR-69040-000, Brazil
| | - Tulika Tulika
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Bjørn G Voldborg
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | | | - J Preben Morth
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Anne Ljungars
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Lise M Grav
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
| | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiologia, Universidad de Costa Rica, San Jose, Costa Rica.
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark.
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5
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Tulika T, Pedersen RW, Rimbault C, Ahmadi S, Rivera‐de‐Torre E, Fernández‐Quintero ML, Loeffler JR, Bohn M, Ljungars A, Ledsgaard L, Voldborg BG, Ruso‐Julve F, Andersen JT, Laustsen AH. Phage display assisted discovery of a pH-dependent anti-α-cobratoxin antibody from a natural variable domain library. Protein Sci 2023; 32:e4821. [PMID: 37897425 PMCID: PMC10659949 DOI: 10.1002/pro.4821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/28/2023] [Accepted: 10/24/2023] [Indexed: 10/30/2023]
Abstract
Recycling IgG antibodies bind to their target antigen at physiological pH in the blood stream and release them upon endocytosis when pH levels drop, allowing the IgG antibodies to be recycled into circulation via FcRn-mediated cellular pathways, while the antigens undergo lysosomal degradation. This enables recycling antibodies to achieve comparable therapeutic effect at lower doses than their non-recycling counterparts. The development of such antibodies is typically achieved by histidine doping of their variable regions or by performing in vitro antibody selection campaigns utilizing histidine doped libraries. Both are strategies that may introduce sequence liabilities. Here, we present a methodology that employs a naïve antibody phage display library, consisting of natural variable domains, to discover antibodies that bind α-cobratoxin from the venom of Naja kaouthia in a pH-dependent manner. As a result, an antibody was discovered that exhibits a 7-fold higher off-rate at pH 5.5 than pH 7.4 in bio-layer interferometry experiments. Interestingly, no histidine residues were found in its variable domains, and in addition, the antibody showed pH-dependent binding to a histidine-devoid antigen mutant. As such, the results demonstrate that pH-dependent antigen-antibody binding may not always be driven by histidine residues. By employing molecular dynamics simulations, different protonation states of titratable residues were found, which potentially could be responsible for the observed pH-dependent antigen binding properties of the antibody. Finally, given the typically high diversity of naïve antibody libraries, the methodology presented here can likely be applied to discover recycling antibodies against different targets ab initio without the need for histidine doping.
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Affiliation(s)
- Tulika Tulika
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Rasmus W. Pedersen
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Charlotte Rimbault
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Shirin Ahmadi
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | | | - Monica L. Fernández‐Quintero
- Center for Molecular Biosciences Innsbruck, Department of GeneralInorganic and Theoretical Chemistry, University of InnsbruckInnsbruckAustria
| | - Johannes R. Loeffler
- Center for Molecular Biosciences Innsbruck, Department of GeneralInorganic and Theoretical Chemistry, University of InnsbruckInnsbruckAustria
| | - Markus‐Frederik Bohn
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Anne Ljungars
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Line Ledsgaard
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Bjørn G. Voldborg
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
| | - Fulgencio Ruso‐Julve
- Department of PharmacologyUniversity of OsloOsloNorway
- Department of ImmunologyOslo University Hospital RikshospitaletOsloNorway
- Precision Immunotherapy AllianceUniversity of OsloOsloNorway
| | - Jan Terje Andersen
- Department of PharmacologyUniversity of OsloOsloNorway
- Department of ImmunologyOslo University Hospital RikshospitaletOsloNorway
- Precision Immunotherapy AllianceUniversity of OsloOsloNorway
| | - Andreas H. Laustsen
- Department of Biotechnology and BiomedicineTechnical University of DenmarkLyngbyDenmark
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6
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Wongjard S, Aiemderm P, Monkhang K, Jaengwang K, Tabtimmai L, Kraiya C, Choowongkomon K, Swainson NM. Selection, alkaline phosphatase fusion, and application of single-chain variable fragment (scFv) specific to NT-proBNP as electrochemical immunosensor for heart failure. Heliyon 2023; 9:e19710. [PMID: 37809905 PMCID: PMC10558999 DOI: 10.1016/j.heliyon.2023.e19710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 08/22/2023] [Accepted: 08/30/2023] [Indexed: 10/10/2023] Open
Abstract
Heart failure has a high global prevalence, with symptoms such as breathlessness, fatigue, and swelling. Early detection is crucial, as the condition worsens over time and can be fatal. This study identified the single-chain variable fragment (scFv) that specifically binds to the heart failure biomarker N-terminal pro B-type natriuretic peptide (NT-proBNP) using biopanning techniques for the development of an alternative diagnostic tool. Ten clones were identified that bound to the target peptide, with two clones (scFv-16 and scFv-36) selected for further analysis. Soluble scFv-16 and scFv-36 were produced and fused with alkaline phosphatase (AP) for potential applications. The binding efficiency and specificity levels of scFv to natriuretic peptides were evaluated using surface plasmon resonance (SPR) analysis. The values of the dissociation constant (KD) for NT-proBNP of scFv-16, scFv-36, scFv-16-AP, and scFv-36-AP were in the range 3.72 × 10-7-3.42 × 10-8 M with high specificity. All constructed scFvs had specificity to NT-proBNP, while not binding to A-type (ANP) and C-type (CNP) natriuretic peptides. When AP was combined, the scFv had a slightly higher yield of expression. The enzyme activity of scFv-36-AP was observed first by the absorption at 405 nm at a minimum of 44 nM and then by the naked eye at a minimum of 88 nM. Additionally, the potential application of NT-proBNP binding scFv was preliminarily investigated using an electrochemical technique to directly detect NT-proBNP in phosphate buffer saline. The results revealed the limit of detection at 69.09 pg/mL, which was less than the cutoff value (150 pg/mL) to discharge patients or healthy people. These findings provided promising biomolecules for the development of a reliable and sensitive diagnostic tool for heart failure.
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Affiliation(s)
- Sureeporn Wongjard
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, 10900, Chatuchak, Bangkok, Thailand
| | - Pongsakorn Aiemderm
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, 10900, Chatuchak, Bangkok, Thailand
| | - Kanchana Monkhang
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, 10900, Chatuchak, Bangkok, Thailand
| | - Kittitat Jaengwang
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, 10900, Chatuchak, Bangkok, Thailand
| | - Lueacha Tabtimmai
- Department of Biotechnology, Faculty of Applied Science, King Mongkut's University of Technology North Bangkok, Bangsue, Bangkok, 10800, Thailand
| | - Charoenkwan Kraiya
- Electrochemistry and Optical Spectroscopy Center of Excellence, Department of Chemistry, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok, 10330, Thailand
| | - Kiattawee Choowongkomon
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, 10900, Chatuchak, Bangkok, Thailand
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7
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Rasri N, Tabtimmai L, Kraiya C, Yamabhai M, Sinthuvanich C, Rattanasrisomporn J, Choowongkomon K. Generation of a Single-Chain Variable Fragment Antibody against Feline Immunoglobulin G for Biosensor Applications. ACS OMEGA 2023; 8:27688-27696. [PMID: 37546656 PMCID: PMC10399156 DOI: 10.1021/acsomega.3c03581] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/05/2023] [Indexed: 08/08/2023]
Abstract
For many decades, feline infectious disease has been among the most common health problems and a leading cause of death in cats. These diseases include toxoplasmosis, feline leukemia virus (FeLV), and particularly feline immunodeficiency virus (FIV) disease. Early diagnosis is essential to increase the chance of successful treatment. Generally, measurement of the IgG level is considered to be indicative of an individual's immune status for a particular pathogen. The antibodies specific to feline IgG are crucial components for the development of a detection kit. In this study, feline IgG-bound scFv was selected using phage display technology. Three rounds of biopanning were conducted against purified feline IgG. Through an indirect enzyme-linked immunosorbent assay (ELISA), two scFv clones demonstrating the best binding ability to feline IgG were chosen for biochemical characterization. In addition, the selected scFv (N14) was expressed and purified in a bacterial system. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the size of the purified N14 was 29 kDa. A sandwich ELISA was used to evaluate the binding capacity of the purified scFv to feline IgG. As expected, the purified N14 had the capacity to bind feline IgG. Furthermore, N14 was modified to create a scFv-alkaline phosphatase (scFv-AP) fusion platform. The surface plasmon resonance (SPR) results revealed that N14-AP bound to feline IgG with an affinity binding value of 0.3 ± 0.496 μM. Additionally, the direct ELISA demonstrated the binding capacity of N14-AP to feline IgG in both cell lysate and purified protein. Moreover, N14-AP could be applied to detect feline IgG based on electrosensing with a detection limit of 10.42 nM. Overall, this study successfully selected a feline IgG-bound scFv and developed a scFv-AP platform that could be further engineered and applied in a feline infectious disease detection kit.
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Affiliation(s)
- Natchaya Rasri
- Department
of Biochemistry, Faculty of Science, Kasetsart
University, Bangkok 10900, Thailand
| | - Lueacha Tabtimmai
- Department
of Biotechnology, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok 10800, Thailand
| | - Charoenkwan Kraiya
- Electrochemistry
and Optical Spectroscopy Center of Excellence, Department of Chemistry,
Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand
| | - Montarop Yamabhai
- Molecular
Biotechnology Laboratory, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Chomdao Sinthuvanich
- Department
of Biochemistry, Faculty of Science, Kasetsart
University, Bangkok 10900, Thailand
| | - Jatuporn Rattanasrisomporn
- Department
of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Kiattawee Choowongkomon
- Department
of Biochemistry, Faculty of Science, Kasetsart
University, Bangkok 10900, Thailand
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8
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Sørensen CV, Ledsgaard L, Wildenauer HHK, Dahl CH, Ebersole TW, Bohn MF, Ljungars A, Jenkins TP, Laustsen AH. Cross-reactivity trends when selecting scFv antibodies against snake toxins using a phage display-based cross-panning strategy. Sci Rep 2023; 13:10181. [PMID: 37349546 PMCID: PMC10287648 DOI: 10.1038/s41598-023-37056-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 06/15/2023] [Indexed: 06/24/2023] Open
Abstract
Antibodies with cross-reactive binding and broad toxin-neutralizing capabilities are advantageous for treating indications such as infectious diseases and animal envenomings. Such antibodies have been successfully selected against closely related antigens using phage display technology. However, the mechanisms driving antibody cross-reactivity typically remain to be elucidated. Therefore, we sought to explore how a previously reported phage display-based cross-panning strategy drives the selection of cross-reactive antibodies using seven different snake toxins belonging to three protein (sub-)families: phospholipases A2, long-chain α-neurotoxins, and short-chain α-neurotoxins. We showcase how cross-panning can increase the chances of discovering cross-reactive single-chain variable fragments (scFvs) from phage display campaigns. Further, we find that the feasibility of discovering cross-reactive antibodies using cross-panning cannot easily be predicted by analyzing the sequence, structural, or surface similarity of the antigens alone. However, when antigens share the (exact) same functions, this seems to increase the chances of selecting cross-reactive antibodies, which may possibly be due to the existence of structurally similar motifs on the antigens.
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Affiliation(s)
- Christoffer V Sørensen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
| | - Line Ledsgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Helen H K Wildenauer
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Camilla H Dahl
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Tasja W Ebersole
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Markus-Frederik Bohn
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Anne Ljungars
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Timothy P Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
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9
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Rimbault C, Knudsen PD, Damsbo A, Boddum K, Ali H, Hackney CM, Ellgaard L, Bohn MF, Laustsen AH. A single-chain variable fragment selected against a conformational epitope of a recombinantly produced snake toxin using phage display. N Biotechnol 2023; 76:23-32. [PMID: 37037303 DOI: 10.1016/j.nbt.2023.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/29/2023] [Accepted: 04/07/2023] [Indexed: 04/12/2023]
Abstract
Phage display technology is a powerful tool for selecting monoclonal antibodies against a diverse set of antigens. Within toxinology, however, it remains challenging to generate monoclonal antibodies against many animal toxins, as they are difficult to obtain from venom. Recombinant toxins have been proposed as a solution to overcome this challenge, but so far, few have been used as antigens to generate neutralizing antibodies. Here, we describe the recombinant expression of α-cobratoxin in E. coli and its successful application as an antigen in a phage display selection campaign. From this campaign, an scFv (single chain variable fragment) was isolated with similar binding affinity to a control scFv generated against the native toxin. The selected scFv recognizes a structural epitope, enabling it to inhibit the interaction between the acetylcholine receptor and the native toxin in vitro. This approach represents the first entirely in vitro antibody selection strategy for generating neutralizing monoclonal antibodies against a snake toxin.
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Affiliation(s)
- Charlotte Rimbault
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Pelle D Knudsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Anna Damsbo
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Kim Boddum
- Sophion Bioscience A/S, DK-2750 Ballerup, Denmark
| | - Hanif Ali
- Quadrucept Bio Ltd, Kemp House, 152 City Road, London, EC1V 2NX, United Kingdom
| | - Celeste M Hackney
- Department of Biology, Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Lars Ellgaard
- Department of Biology, Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Markus-Frederik Bohn
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.
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10
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González-Davis O, Villagrana-Escareño MV, Trujillo MA, Gama P, Chauhan K, Vazquez-Duhalt R. Virus-like nanoparticles as enzyme carriers for Enzyme Replacement Therapy (ERT). Virology 2023; 580:73-87. [PMID: 36791560 DOI: 10.1016/j.virol.2023.01.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 01/20/2023] [Accepted: 01/30/2023] [Indexed: 02/09/2023]
Abstract
Enzyme replacement therapy (ERT) has been used to treat a few of the many existing diseases which are originated from the lack of, or low enzymatic activity. Exogenous enzymes are administered to contend with the enzymatic activity deficiency. Enzymatic nanoreactors based on the enzyme encapsulation inside of virus-like particles (VLPs) appear as an interesting alternative for ERT. VLPs are excellent delivery vehicles for therapeutic enzymes as they are biodegradable, uniformly organized, and porous nanostructures that transport and could protect the biocatalyst from the external environment without much affecting the bioactivity. Consequently, significant efforts have been made in the production processes of virus-based enzymatic nanoreactors and their functionalization, which are critically reviewed. The use of virus-based enzymatic nanoreactors for the treatment of lysosomal storage diseases such as Gaucher, Fabry, and Pompe diseases, as well as potential therapies for galactosemia, and Hurler and Hunter syndromes are discussed.
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Affiliation(s)
- Oscar González-Davis
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California, 22860, Mexico
| | - Maria V Villagrana-Escareño
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California, 22860, Mexico
| | - Mario A Trujillo
- School of Medicine, Universidad Xochicalco, Ensenada, Baja California, Mexico
| | - Pedro Gama
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California, 22860, Mexico
| | - Kanchan Chauhan
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California, 22860, Mexico
| | - Rafael Vazquez-Duhalt
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California, 22860, Mexico.
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11
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Bridge T, Sachdeva A. Engineering Homogeneous Photoactive Antibody Fragments. Methods Mol Biol 2023; 2676:21-40. [PMID: 37277622 DOI: 10.1007/978-1-0716-3251-2_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Genetically encoded site-specifically incorporated noncanonical amino acids (ncAAs) have been used to modulate properties of several proteins. Here, we describe a procedure for engineering photoactive antibody fragments that bind to their target antigen only after irradiation with 365 nm light. The procedure starts with identification of tyrosine residues in antibody fragments that are important for antibody-antigen binding and thus targets for replacement with photocaged tyrosine (pcY). This is followed by cloning of plasmids and expression of pcY-containing antibody fragments in E. coli. Finally, we describe a cost-effective and biologically-relevant method for measuring the binding affinity of photoactive antibody fragments to antigens expressed on the surface of live cancer cells.
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Affiliation(s)
- Thomas Bridge
- School of Chemistry, University of East Anglia, Norwich, UK
| | - Amit Sachdeva
- School of Chemistry, University of East Anglia, Norwich, UK.
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12
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Muñoz-López P, Ribas-Aparicio RM, Becerra-Báez EI, Fraga-Pérez K, Flores-Martínez LF, Mateos-Chávez AA, Luria-Pérez R. Single-Chain Fragment Variable: Recent Progress in Cancer Diagnosis and Therapy. Cancers (Basel) 2022; 14:cancers14174206. [PMID: 36077739 PMCID: PMC9455005 DOI: 10.3390/cancers14174206] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 08/25/2022] [Accepted: 08/27/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Recombinant antibody fragments have shown remarkable potential as diagnostic and therapeutic tools in the fight against cancer. The single-chain fragment variable (scFv) that contains the complete antigen-binding domains of a whole antibody, has several advantages such as a high specificity and affinity for antigens, a low immunogenicity, and the proven ability to penetrate tumor tissues and diffuse. This review provides an overview of the current studies on the principle, generation, and applications of scFvs, particularly in the diagnosis and therapy of cancer, and underscores their potential use in clinical trials. Abstract Cancer remains a public health problem worldwide. Although conventional therapies have led to some excellent outcomes, some patients fail to respond to treatment, they have few therapeutic alternatives and a poor survival prognosis. Several strategies have been proposed to overcome this issue. The most recent approach is immunotherapy, particularly the use of recombinant antibodies and their derivatives, such as the single-chain fragment variable (scFv) containing the complete antigen-binding domains of a whole antibody that successfully targets tumor cells. This review describes the recent progress made with scFvs as a cancer diagnostic and therapeutic tool, with an emphasis on preclinical approaches and their potential use in clinical trials.
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Affiliation(s)
- Paola Muñoz-López
- Unit of Investigative Research on Hemato-Oncological Diseases, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, Mexico City 06720, Mexico
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional (IPN), Prolongación de Carpio y Plan de Ayala S/N, Mexico City 11340, Mexico
| | - Rosa María Ribas-Aparicio
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional (IPN), Prolongación de Carpio y Plan de Ayala S/N, Mexico City 11340, Mexico
| | - Elayne Irene Becerra-Báez
- Unit of Investigative Research on Hemato-Oncological Diseases, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, Mexico City 06720, Mexico
- Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional (IPN), Prolongación de Carpio y Plan de Ayala S/N, Mexico City 11340, Mexico
| | - Karla Fraga-Pérez
- Unit of Investigative Research on Hemato-Oncological Diseases, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, Mexico City 06720, Mexico
| | - Luis Fernando Flores-Martínez
- Unit of Investigative Research on Hemato-Oncological Diseases, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, Mexico City 06720, Mexico
| | - Armando Alfredo Mateos-Chávez
- Unit of Investigative Research on Hemato-Oncological Diseases, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, Mexico City 06720, Mexico
| | - Rosendo Luria-Pérez
- Unit of Investigative Research on Hemato-Oncological Diseases, Hospital Infantil de México Federico Gómez, Doctor Márquez 162, Mexico City 06720, Mexico
- Correspondence: ; Tel.: +52-(55)-5228-9917 (ext. 4401)
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13
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Wang Y, Yuan W, Guo S, Li Q, Chen X, Li C, Liu Q, Sun L, Chen Z, Yuan Z, Luo C, Chen S, Tong S, Nassal M, Wen YM, Wang YX. A 33-residue peptide tag increases solubility and stability of Escherichia coli produced single-chain antibody fragments. Nat Commun 2022; 13:4614. [PMID: 35941164 PMCID: PMC9359998 DOI: 10.1038/s41467-022-32423-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 07/29/2022] [Indexed: 11/29/2022] Open
Abstract
Single-chain variable fragments (scFvs), composed of variable domains of heavy and light chains of an antibody joined by a linker, share antigen binding capacity with their parental antibody. Due to intrinsically low solubility and stability, only two Escherichia coli-produced scFvs have been approved for therapy. Here we report that a 33-residue peptide, termed P17 tag, increases the solubility of multiple scFvs produced in Escherichia coli SHuffle strain by up to 11.6 fold. Hydrophilic sequence, especially charged residues, but not the predicted α-helical secondary structure of P17 tag, contribute to the solubility enhancement. Notably, the P17 tag elevates the thermostability of scFv as efficiently as intra-domain disulfide bonds. Moreover, a P17-tagged scFv targeting hepatitis B virus surface proteins shows over two-fold higher antigen-binding affinity and virus-neutralizing activity than the untagged version. These data strongly suggest a type I intramolecular chaperone-like activity of the P17 tag. Hence, the P17 tag could benefit the research, production, and application of scFv. Low solubility and stability of Escherichia coli produced single chain variable fragments (scFvs) restrict their applications. Here the authors report a 33-residue peptide tag which simultaneously increases the solubility and thermostability of multiple scFvs produced in Escherichia coli SHuffle strain.
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Affiliation(s)
- Yang Wang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wenjie Yuan
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Siqi Guo
- Drug Discovery and Design Center, the Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmacy, Nanchang University, Nanchang, China
| | - Qiqi Li
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaomei Chen
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Cheng Li
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qianying Liu
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Lei Sun
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Zhenguo Chen
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Zhenghong Yuan
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Cheng Luo
- Drug Discovery and Design Center, the Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China
| | - Shijie Chen
- Drug Discovery and Design Center, the Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
| | - Shuping Tong
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Michael Nassal
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Yu-Mei Wen
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yong-Xiang Wang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
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14
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Fiil BK, Thrane SW, Pichler M, Kittilä T, Ledsgaard L, Ahmadi S, Maigaard Hermansen GM, Jelsbak L, Lauridsen C, Brix S, Laustsen AH. Orally-active bivalent VHH construct prevents proliferation of F4+ enterotoxigenic Escherichia coli in weaned piglets. iScience 2022; 25:104003. [PMID: 35310945 PMCID: PMC8931358 DOI: 10.1016/j.isci.2022.104003] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/21/2021] [Accepted: 02/25/2022] [Indexed: 11/25/2022] Open
Abstract
A major challenge in industrial pig production is the prevalence of post-weaning diarrhea (PWD) in piglets, often caused by enterotoxigenic Escherichia coli (ETEC). The increased use of antibiotics and zinc oxide to treat PWD has raised global concerns regarding antimicrobial resistance development and environmental pollution. Still, alternative treatments targeting ETEC and counteracting PWD are largely lacking. Here, we report the design of a pH, temperature, and protease-stable bivalent VHH-based protein BL1.2 that cross-links a F4+ ETEC model strain by selectively binding to its fimbriae. This protein inhibits F4+ ETEC adhesion to porcine epithelial cells ex vivo and decreases F4+ ETEC proliferation when administrated as a feed additive to weaned F4+ ETEC challenged piglets. These findings highlight the potential of a highly specific bivalent VHH-based feed additive in effectively delimiting pathogenic F4+ ETEC bacteria proliferation in piglets and may represent a sustainable solution for managing PWD while circumventing antimicrobial resistance development. A binding protein was designed as a bivalent VHH construct with a (GGGGS)3 linker The protein can cross-link F4+ enterotoxigenic Escherichia coli (ETEC) in vitro The protein can prevent adhesion of F4+ ETEC to porcine epithelial cells ex vivo The protein can prevent proliferation of F4+ ETEC in piglets
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15
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Ledsgaard L, Laustsen AH, Pus U, Wade J, Villar P, Boddum K, Slavny P, Masters EW, Arias AS, Oscoz S, Griffiths DT, Luther AM, Lindholm M, Leah RA, Møller MS, Ali H, McCafferty J, Lomonte B, Gutiérrez JM, Karatt-Vellatt A. In vitro discovery of a human monoclonal antibody that neutralizes lethality of cobra snake venom. MAbs 2022; 14:2085536. [PMID: 35699567 PMCID: PMC9225616 DOI: 10.1080/19420862.2022.2085536] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/31/2022] [Indexed: 10/24/2022] Open
Abstract
The monocled cobra (Naja kaouthia) is among the most feared snakes in Southeast Asia due to its toxicity, which is predominantly derived from long-chain α-neurotoxins. The only specific treatment for snakebite envenoming is antivenom based on animal-derived polyclonal antibodies. Despite the lifesaving importance of these medicines, major limitations in safety, supply consistency, and efficacy create a need for improved treatments. Here, we describe the discovery and subsequent optimization of a recombinant human monoclonal immunoglobulin G antibody against α-cobratoxin using phage display technology. Affinity maturation by light chain-shuffling resulted in a significant increase in in vitro neutralization potency and in vivo efficacy. The optimized antibody prevented lethality when incubated with N. kaouthia whole venom prior to intravenous injection. This study is the first to demonstrate neutralization of whole snake venom by a single recombinant monoclonal antibody, thus providing a tantalizing prospect of bringing recombinant antivenoms based on human monoclonal or oligoclonal antibodies to the clinic.
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Affiliation(s)
- Line Ledsgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Andreas H. Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Urska Pus
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jack Wade
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | | | | | | | - Ana S. Arias
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Saioa Oscoz
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | | | | | | | - Marie Sofie Møller
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Hanif Ali
- Quadrucept Bio, Cambourne, United Kingdom
| | | | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - José M. Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
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16
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Chauhan K, Zárate‐Romero A, Sengar P, Medrano C, Vazquez‐Duhalt R. Catalytic Kinetics Considerations and Molecular Tools for the Design of Multienzymatic Cascade Nanoreactors. ChemCatChem 2021. [DOI: 10.1002/cctc.202100604] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kanchan Chauhan
- Department of Bionanotechnology Center for Nanosciences and Nanotechnology Universidad Nacional Autónoma de México Km 107 carretera Tijuana-Ensenada Ensenada Baja California 22860 Mexico
| | - Andrés Zárate‐Romero
- Department of Bionanotechnology Center for Nanosciences and Nanotechnology Universidad Nacional Autónoma de México Km 107 carretera Tijuana-Ensenada Ensenada Baja California 22860 Mexico
- Cátedra Consejo Nacional de Ciencia y Tecnología CNyN-UNAM Ensenada Baja California 22860 Mexico
| | - Prakhar Sengar
- Department of Bionanotechnology Center for Nanosciences and Nanotechnology Universidad Nacional Autónoma de México Km 107 carretera Tijuana-Ensenada Ensenada Baja California 22860 Mexico
| | - Carlos Medrano
- Department of Bionanotechnology Center for Nanosciences and Nanotechnology Universidad Nacional Autónoma de México Km 107 carretera Tijuana-Ensenada Ensenada Baja California 22860 Mexico
| | - Rafael Vazquez‐Duhalt
- Department of Bionanotechnology Center for Nanosciences and Nanotechnology Universidad Nacional Autónoma de México Km 107 carretera Tijuana-Ensenada Ensenada Baja California 22860 Mexico
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17
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Nikolova G, Georgieva Y, Atanasova A, Radulova G, Kapogianni A, Tsacheva I. Autoinduction as Means for Optimization of the Heterologous Expression of Recombinant Single-Chain Fv (scFv) Antibodies. Mol Biotechnol 2021; 63:1049-1056. [PMID: 34215946 DOI: 10.1007/s12033-021-00363-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 06/20/2021] [Indexed: 11/29/2022]
Abstract
The monoclonal antibodies and the recombinant antibody fragments are widely used in the biotechnology studies and in medicine as a powerful therapeutic and diagnostic tool. The most commonly used recombinant antibody fragments are single-chain fragment variable (scFv) because of their small size and minimal immunogenicity while still retaining high-affinity antigen binding. A wide range of expression systems such as bacterial and eukaryotic cell systems enable the sufficient production of scFv antibodies. However, their stable expression in soluble form and correct protein folding are often insufficient. In the present study, we present the autoinduction as a key element of the optimized scheme for heterologous expression of human monoclonal scFv antibodies (clones A1 and A12) in Escherichia coli HB2151, which resulted in two-fold increase of the total protein yield in 24 h.
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Affiliation(s)
- Ginka Nikolova
- Department of Biochemistry, Faculty of Biology, Sofia University, 8 Dragan Tsankov, Sofia, Bulgaria
| | - Yana Georgieva
- Clinical Laboratory and Immunology, Military Medical Academy, 3 Sv. Georgi Sofiyski, Sofia, Bulgaria
| | - Alexandra Atanasova
- Department of Biochemistry, Faculty of Biology, Sofia University, 8 Dragan Tsankov, Sofia, Bulgaria
| | - Gabriela Radulova
- Department of Biochemistry, Faculty of Biology, Sofia University, 8 Dragan Tsankov, Sofia, Bulgaria
| | - Alexandra Kapogianni
- Department of Biochemistry, Faculty of Biology, Sofia University, 8 Dragan Tsankov, Sofia, Bulgaria
| | - Ivanka Tsacheva
- Department of Biochemistry, Faculty of Biology, Sofia University, 8 Dragan Tsankov, Sofia, Bulgaria.
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18
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Combining the advantages of prokaryotic expression and T7 phage display systems to obtain antigens for antibody preparation. Protein Expr Purif 2020; 184:105808. [PMID: 33309973 DOI: 10.1016/j.pep.2020.105808] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 12/04/2020] [Accepted: 12/08/2020] [Indexed: 01/10/2023]
Abstract
The gene encoding the phage major capsid protein 10A was cloned into the prokaryotic expression vector pET24a, and a 6XHis-tag was fused to the 3'-end of the 10A gene to verify complete expression. The recombinant plasmid was transformed into Escherichia coli (E. coli) BL21 (DE3) cells, and 10A expression was induced by IPTG. SDS-PAGE and Western blot were used to confirm the target protein expression. The T7Select10-3b vector was added to the cultured bacteria expressing 10A at a multiplicity of infection (MOI) ranging from 0.01 to 0.1, and complete lysis of the bacteria was monitored by absorbance changes in the medium. The recombinant phage (reP) was harvested by PEG/NaCl sedimentation and resuspended in PBS. ELISA was performed to verify the presence of the 6XHis-tag on the surface of reP. The 10A-fusion expression vectors (pET10A-flag, pET10A-egfp, and pET10A-pct) were constructed, and fusion proteins were expressed and detected by the same method. The corresponding rePs (reP-Flag, reP-EGFP, and reP-PCT) were prepared by T7Select10-3b infection. After the expression of the peptides/proteins on the reP surfaces was confirmed, reP-Flag and reP-PCT were used to immunize mice to prepare anti-Flag and anti-PCT antibodies. The results showed that rePs prepared using the 10A-fusion vector and T7Select10-3b can be used as antigens to immunize mice and prepare antibodies. This method may be able to meet the rapid antigen preparation requirements for antibody production. Notably, the recombinant phage (reP) described in this study was obtained by the sedimentation method from T7Select10-3b-infected E. coli BL21 (DE3) cells carrying the major capsid protein 10A expression vector or 10A-fusion protein vector.
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19
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Føns S, Ledsgaard L, Nikolaev MV, Vassilevski AA, Sørensen CV, Chevalier MK, Fiebig M, Laustsen AH. Discovery of a Recombinant Human Monoclonal Immunoglobulin G Antibody Against α-Latrotoxin From the Mediterranean Black Widow Spider ( Latrodectus tredecimguttatus). Front Immunol 2020; 11:587825. [PMID: 33262768 PMCID: PMC7688514 DOI: 10.3389/fimmu.2020.587825] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/19/2020] [Indexed: 12/26/2022] Open
Abstract
Widow spiders are among the few spider species worldwide that can cause serious envenoming in humans. The clinical syndrome resulting from Latrodectus spp. envenoming is called latrodectism and characterized by pain (local or regional) associated with diaphoresis and nonspecific systemic effects. The syndrome is caused by α-latrotoxin, a ~130 kDa neurotoxin that induces massive neurotransmitter release. Due to this function, α-latrotoxin has played a fundamental role as a tool in the study of neuroexocytosis. Nevertheless, some questions concerning its mode of action remain unresolved today. The diagnosis of latrodectism is purely clinical, combined with the patient's history of spider bite, as no analytical assays exist to detect widow spider venom. By utilizing antibody phage display technology, we here report the discovery of the first recombinant human monoclonal immunoglobulin G antibody (TPL0020_02_G9) that binds α-latrotoxin from the Mediterranean black widow spider (Latrodectus tredecimguttatus) and show neutralization efficacy ex vivo. Such antibody can be used as an affinity reagent for research and diagnostic purposes, providing researchers with a novel tool for more sophisticated experimentation and analysis. Moreover, it may also find therapeutic application in future.
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Affiliation(s)
- Sofie Føns
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Line Ledsgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Maxim V. Nikolaev
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Saint Petersburg, Russia
| | - Alexander A. Vassilevski
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Christoffer V. Sørensen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Manon K. Chevalier
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | - Andreas H. Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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20
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Hanyu Y, Kato M. Screening Antibody Libraries with Colony Assay Using scFv-Alkaline Phosphatase Fusion Proteins. Molecules 2020; 25:molecules25122905. [PMID: 32599779 PMCID: PMC7356641 DOI: 10.3390/molecules25122905] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/20/2020] [Accepted: 06/21/2020] [Indexed: 01/17/2023] Open
Abstract
Screening antibody libraries is an important step in establishing recombinant monoclonal antibodies. The colony assay can identify positive clones without almost any false-positives; however, its antibody library is smaller than those used in other recombinant screening methods such as phage display. Thus, to improve the efficiency of colony assays, it is necessary to increase library size per screening. Here, we report developing a colony assay with single-chain variable fragment (scFv) fused to the N-terminus of bacterial alkaline phosphatase (scFv-PhoA). The scFv-PhoA library was constructed in an expression vector specifically designed for this study. Use of this library allowed the successful and direct detection of positive clones exhibiting PhoA activity, without the need for a secondary antibody. Colony assay screening with scFv-PhoA is simple, rapid, offers a higher success rate than previous methods based on scFv libraries, and—most importantly—it enables high-throughput procedures.
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Affiliation(s)
- Yoshiro Hanyu
- Biomaterials Research Group, Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566, Japan
- Correspondence: ; Tel.: +81-298-61-5542
| | - Mieko Kato
- Department of Biochemistry, Bio-Peak Co., Ltd., 584-70 Shimonojo, Takasaki 370-0854, Japan;
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21
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CD229 CAR T cells eliminate multiple myeloma and tumor propagating cells without fratricide. Nat Commun 2020; 11:798. [PMID: 32034142 PMCID: PMC7005855 DOI: 10.1038/s41467-020-14619-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 01/21/2020] [Indexed: 01/17/2023] Open
Abstract
Multiple myeloma (MM) is a plasma cell malignancy and most patients eventually succumb to the disease. Chimeric antigen receptor (CAR) T cells targeting B-Cell Maturation Antigen (BCMA) on MM cells have shown high-response rates, but limited durability. CD229/LY9 is a cell surface receptor present on B and T lymphocytes that is universally and strongly expressed on MM plasma cells. Here, we develop CD229 CAR T cells that are highly active in vitro and in vivo against MM plasma cells, memory B cells, and MM-propagating cells. We do not observe fratricide during CD229 CAR T cell production, as CD229 is downregulated in T cells during activation. In addition, while CD229 CAR T cells target normal CD229high T cells, they spare functional CD229neg/low T cells. These findings indicate that CD229 CAR T cells may be an effective treatment for patients with MM.
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22
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Somogyi M, Szimler T, Baksa A, Végh BM, Bakos T, Paréj K, Ádám C, Zsigmond Á, Megyeri M, Flachner B, Sajó R, Gráczer É, Závodszky P, Hajdú I, Beinrohr L. A versatile modular vector set for optimizing protein expression among bacterial, yeast, insect and mammalian hosts. PLoS One 2019; 14:e0227110. [PMID: 31887188 PMCID: PMC6936851 DOI: 10.1371/journal.pone.0227110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 12/12/2019] [Indexed: 12/28/2022] Open
Abstract
We have developed a unified, versatile vector set for expression of recombinant proteins, fit for use in any bacterial, yeast, insect or mammalian cell host. The advantage of this system is its versatility at the vector level, achieved by the introduction of a novel expression cassette. This cassette contains a unified multi-cloning site, affinity tags, protease cleavable linkers, an optional secretion signal, and common restriction endonuclease sites at key positions. This way, genes of interest and all elements of the cassette can be switched freely among the vectors, using restriction digestion and ligation without the need of polymerase chain reaction (PCR). This vector set allows rapid protein expression screening of various hosts and affinity tags. The reason behind this approach was that it is difficult to predict which expression host and which affinity tag will lead to functional expression. The new system is based on four optimized and frequently used expression systems (Escherichia coli pET, the yeast Pichia pastoris, pVL and pIEx for Spodoptera frugiperda insect cells and pLEXm based mammalian systems), which were modified as described above. The resulting vector set was named pONE series. We have successfully applied the pONE vector set for expression of the following human proteins: the tumour suppressor RASSF1A and the protein kinases Aurora A and LIMK1. Finally, we used it to express the large multidomain protein, Rho-associated protein kinase 2 (ROCK2, 164 kDa) and demonstrated that the yeast Pichia pastoris reproducibly expresses the large ROCK2 kinase with identical activity to the insect cell produced counterpart. To our knowledge this is among the largest proteins ever expressed in yeast. This demonstrates that the cost-effective yeast system can match and replace the industry-standard insect cell expression system even for large and complex mammalian proteins. These experiments demonstrate the applicability of our pONE vector set.
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Affiliation(s)
- Márk Somogyi
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Tamás Szimler
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Attila Baksa
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Barbara M. Végh
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Tamás Bakos
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Katalin Paréj
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Csaba Ádám
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Áron Zsigmond
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Márton Megyeri
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Beáta Flachner
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Ráchel Sajó
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Éva Gráczer
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - Péter Závodszky
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
| | - István Hajdú
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
- * E-mail: (LB); (IH)
| | - László Beinrohr
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pázmány Péter sétány, Budapest, Hungary
- * E-mail: (LB); (IH)
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23
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Bridge T, Shaikh SA, Thomas P, Botta J, McCormick PJ, Sachdeva A. Site-Specific Encoding of Photoactivity in Antibodies Enables Light-Mediated Antibody-Antigen Binding on Live Cells. Angew Chem Int Ed Engl 2019; 58:17986-17993. [PMID: 31609054 PMCID: PMC6973043 DOI: 10.1002/anie.201908655] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/11/2019] [Indexed: 12/20/2022]
Abstract
Antibodies have found applications in several fields, including, medicine, diagnostics, and nanotechnology, yet methods to modulate antibody-antigen binding using an external agent remain limited. Here, we have developed photoactive antibody fragments by genetic site-specific replacement of single tyrosine residues with photocaged tyrosine, in an antibody fragment, 7D12. A simple and robust assay is adopted to evaluate the light-mediated binding of 7D12 mutants to its target, epidermal growth factor receptor (EGFR), on the surface of cancer cells. Presence of photocaged tyrosine reduces 7D12-EGFR binding affinity by over 20-fold in two out of three 7D12 mutants studied, and binding is restored upon exposure to 365 nm light. Molecular dynamics simulations explain the difference in effect of photocaging on 7D12-EGFR interaction among the mutants. Finally, we demonstrate the application of photoactive antibodies in delivering fluorophores to EGFR-positive live cancer cells in a light-dependent manner.
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Affiliation(s)
- Thomas Bridge
- School of ChemistryUniversity of East AngliaNorwichNR4 7TJUK
| | - Saher A. Shaikh
- School of ChemistryUniversity of East AngliaNorwichNR4 7TJUK
| | - Paul Thomas
- The Henry Wellcome Laboratory of Cell ImagingUniversity of East AngliaNorwichNR4 7TJUK
| | - Joaquin Botta
- Centre of EndocrinologyWilliam Harvey Research InstituteQueen Mary University LondonCharterhouse SquareLondonEC1M 6BQUK
| | - Peter J. McCormick
- Centre of EndocrinologyWilliam Harvey Research InstituteQueen Mary University LondonCharterhouse SquareLondonEC1M 6BQUK
| | - Amit Sachdeva
- School of ChemistryUniversity of East AngliaNorwichNR4 7TJUK
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24
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Bridge T, Shaikh SA, Thomas P, Botta J, McCormick PJ, Sachdeva A. Site‐Specific Encoding of Photoactivity in Antibodies Enables Light‐Mediated Antibody–Antigen Binding on Live Cells. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201908655] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Thomas Bridge
- School of ChemistryUniversity of East Anglia Norwich NR4 7TJ UK
| | - Saher A. Shaikh
- School of ChemistryUniversity of East Anglia Norwich NR4 7TJ UK
| | - Paul Thomas
- The Henry Wellcome Laboratory of Cell ImagingUniversity of East Anglia Norwich NR4 7TJ UK
| | - Joaquin Botta
- Centre of EndocrinologyWilliam Harvey Research InstituteQueen Mary University London Charterhouse Square London EC1M 6BQ UK
| | - Peter J. McCormick
- Centre of EndocrinologyWilliam Harvey Research InstituteQueen Mary University London Charterhouse Square London EC1M 6BQ UK
| | - Amit Sachdeva
- School of ChemistryUniversity of East Anglia Norwich NR4 7TJ UK
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25
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Hannachi E, Bouratbine A, Mousli M. Enhancing the detection of Toxoplasma gondii via an anti-SAG1 scFv-alkaline phosphatase immunoconjugate. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2019; 23:e00360. [PMID: 31341791 PMCID: PMC6630058 DOI: 10.1016/j.btre.2019.e00360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 06/29/2019] [Accepted: 06/30/2019] [Indexed: 12/11/2022]
Abstract
The purpose of this study was to implement a fluorometric method for enhancing the detection sensitivity of Toxoplasma gondii in biological fluids. To address this challenge, we designed and produced a recombinant immunoconjugate tool based on a single-chain antibody fragment anti-T. gondii SAG1 antigen (scFvSG15) genetically fused to the bacterial alkaline phosphatase (AP) using 4-methyl-umbelliferyl-phosphate as fluorogenic substrate. The anti-SAG1 scFv-AP conjugate was fully bifunctional and was used successfully in different assays including immunoblot, fluorometric ELISA and direct immunofluorescence. The fluorometric immunoassay afforded an extremely low detection limit (1 tachyzoite/well), which was in agreement with the real-time PCR control test. The immunofluorescence imaging has provided captivating visual evidence of T. gondii detection. These results strongly suggest that the recombinant anti-SAG1-AP conjugate generated here might serve as useful and highly sensitive immunoassay probe to direct detect T. gondii in a one-step procedure, opening up new perspectives for diagnosis of toxoplasmosis.
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Affiliation(s)
| | | | - Mohamed Mousli
- Laboratoire de Parasitologie Médicale, Biotechnologies et Biomolécules, LR11-IPT06, Institut Pasteur de Tunis, Université Tunis El-Manar, 13 Place Pasteur -BP74, 1002 Tunis-Belvédère, Tunisia
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26
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In vivo neutralization of dendrotoxin-mediated neurotoxicity of black mamba venom by oligoclonal human IgG antibodies. Nat Commun 2018; 9:3928. [PMID: 30279409 PMCID: PMC6168529 DOI: 10.1038/s41467-018-06086-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 08/17/2018] [Indexed: 11/24/2022] Open
Abstract
The black mamba (Dendroaspis polylepis) is one of the most feared snake species of the African savanna. It has a potent, fast-acting neurotoxic venom comprised of dendrotoxins and α-neurotoxins associated with high fatality in untreated victims. Current antivenoms are both scarce on the African continent and present a number of drawbacks as they are derived from the plasma of hyper-immunized large mammals. Here, we describe the development of an experimental recombinant antivenom by a combined toxicovenomics and phage display approach. The recombinant antivenom is based on a cocktail of fully human immunoglobulin G (IgG) monoclonal antibodies capable of neutralizing dendrotoxin-mediated neurotoxicity of black mamba whole venom in a rodent model. Our results show the potential use of fully human monoclonal IgGs against animal toxins and the first use of oligoclonal human IgG mixtures against experimental snakebite envenoming. Current anti-venoms against black mamba (Dendroaspis polylepis) bites are animal-derived and associated with several limitations. Here, Laustsen and colleagues develop an experimental recombinant anti-venom based on oligoclonal human IgG antibodies and establish its potential protective value in neutralizing dendrotoxin-mediated neurotoxicity using venom challenge in vivo models.
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27
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Botkjaer KA, Kwok HF, Terp MG, Karatt-Vellatt A, Santamaria S, McCafferty J, Andreasen PA, Itoh Y, Ditzel HJ, Murphy G. Development of a specific affinity-matured exosite inhibitor to MT1-MMP that efficiently inhibits tumor cell invasion in vitro and metastasis in vivo. Oncotarget 2017; 7:16773-92. [PMID: 26934448 PMCID: PMC4941350 DOI: 10.18632/oncotarget.7780] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 01/23/2016] [Indexed: 11/25/2022] Open
Abstract
The membrane-associated matrix metalloproteinase-14, MT1-MMP, has been implicated in pericellular proteolysis with an important role in cellular invasion of collagenous tissues. It is substantially upregulated in various cancers and rheumatoid arthritis, and has been considered as a potential therapeutic target. Here, we report the identification of antibody fragments to MT1-MMP that potently and specifically inhibit its cell surface functions. Lead antibody clones displayed inhibitory activity towards pro-MMP-2 activation, collagen-film degradation and gelatin-film degradation, and were shown to bind to the MT1-MMP catalytic domain outside the active site cleft, inhibiting binding to triple helical collagen. Affinity maturation using CDR3 randomization created a second generation of antibody fragments with dissociation constants down to 0.11 nM, corresponding to an improved affinity of 332-fold with the ability to interfere with cell-surface MT1-MMP functions, displaying IC50 values down to 5 nM. Importantly, the new inhibitors were able to inhibit collagen invasion by tumor-cells in vitro and in vivo primary tumor growth and metastasis of MDA-MB-231 cells in a mouse orthotopic xenograft model. Herein is the first demonstration that an inhibitory antibody targeting sites outside the catalytic cleft of MT1-MMP can effectively abrogate its in vivo activity during tumorigenesis and metastasis.
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Affiliation(s)
- Kenneth A Botkjaer
- Department of Oncology, University of Cambridge, Cancer Research UK Cambridge Institute, Li Ka Shing Centre, Cambridge, U.K
| | - Hang Fai Kwok
- Department of Oncology, University of Cambridge, Cancer Research UK Cambridge Institute, Li Ka Shing Centre, Cambridge, U.K.,Faculty of Health Sciences, University of Macau, Taipa, Macau SAR
| | - Mikkel G Terp
- Department of Cancer and Inflammation Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | | | - Salvatore Santamaria
- Kennedy Institute of Rheumatology, University of Oxford, Headington, Oxford, U.K
| | | | - Peter A Andreasen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,Danish-Chinese Centre for Proteases and Cancer, Aarhus University, Aarhus, Denmark
| | - Yoshifumi Itoh
- Kennedy Institute of Rheumatology, University of Oxford, Headington, Oxford, U.K
| | - Henrik J Ditzel
- Department of Cancer and Inflammation Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Oncology, Odense University Hospital, Odense, Denmark
| | - Gillian Murphy
- Department of Oncology, University of Cambridge, Cancer Research UK Cambridge Institute, Li Ka Shing Centre, Cambridge, U.K
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28
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Haylock AK, Nilvebrant J, Mortensen A, Velikyan I, Nestor M, Falk R. Generation and evaluation of antibody agents for molecular imaging of CD44v6-expressing cancers. Oncotarget 2017; 8:65152-65170. [PMID: 29029420 PMCID: PMC5630320 DOI: 10.18632/oncotarget.17996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 04/26/2017] [Indexed: 11/25/2022] Open
Abstract
AIM The aim of this study was to generate and characterize scFv antibodies directed to human CD44v6, as well as to radiolabel and evaluate top candidates in vitro and in vivo for their potential use in CD44v6-targeted molecular imaging in cancer patients. MATERIALS AND METHODS Phage display selections were used to isolate CD44v6-specific scFvs. A chain shuffling strategy was employed for affinity maturation based on a set of CD44v6-specific first-generation clones. Two second-generation scFv clones were then chosen for labeling with 111In or 125I and assessed for CD44v6-specific binding on cultured tumor cells. In vivo uptake and distribution was evaluated in tumor-bearing mice using a dual tumor model. Finally, a proof-of-concept small animal PET-CT study was performed on one of the candidates labeled with 124I. RESULTS Two affinity-matured clones, CD44v6-scFv-A11 and CD44v6-scFv-H12, displayed promising binding kinetics. Seven out of eight radiolabeled conjugates demonstrated CD44v6-specific binding. In vivo studies on selected candidates demonstrated very advantageous tumor-to-organ ratios, in particular for iodinated conjugates, where 125I-labeled scFvs exhibited favorable kinetics and tumor-to-blood ratios above five already at 24 hours p.i.. The small animal PET-CT study using 124I-labeled CD44v6-scFv-H12 was in line with the biodistribution data, clearly visualizing the high CD44v6-expressing tumor. CONCLUSION The single chain fragments, CD44v6-scFv-A11 and CD44v6-scFv-H12 specifically bind to CD44v6, and the radiolabeled counterparts provide high tumor-to-blood ratios and fast clearance from organs and blood. We conclude that radioiodinated CD44v6-scFv-A11 and CD44v6-scFv-H12 possess features highly suitable for stringent molecular imaging.
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Affiliation(s)
- Anna-Karin Haylock
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Johan Nilvebrant
- Division of Protein Technology, School of Biotechnology, Royal Institute of Technology, Stockholm, Sweden
| | - Anja Mortensen
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Irina Velikyan
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Marika Nestor
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Ronny Falk
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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29
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DiCara DM, Chirgadze DY, Pope AR, Karatt-Vellatt A, Winter A, Slavny P, van den Heuvel J, Parthiban K, Holland J, Packman LC, Mavria G, Hoffmann J, Birchmeier W, Gherardi E, McCafferty J. Characterization and structural determination of a new anti-MET function-blocking antibody with binding epitope distinct from the ligand binding domain. Sci Rep 2017; 7:9000. [PMID: 28827556 PMCID: PMC5567289 DOI: 10.1038/s41598-017-09460-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 07/25/2017] [Indexed: 12/18/2022] Open
Abstract
The growth and motility factor Hepatocyte Growth Factor/Scatter Factor (HGF/SF) and its receptor, the product of the MET proto-oncogene, promote invasion and metastasis of tumor cells and have been considered potential targets for cancer therapy. We generated a new Met-blocking antibody which binds outside the ligand-binding site, and determined the crystal structure of the Fab in complex with its target, which identifies the binding site as the Met Ig1 domain. The antibody, 107_A07, inhibited HGF/SF-induced cell migration and proliferation in vitro and inhibited growth of tumor xenografts in vivo. In biochemical assays, 107_A07 competes with both HGF/SF and its truncated splice variant NK1 for MET binding, despite the location of the antibody epitope on a domain (Ig1) not reported to bind NK1 or HGF/SF. Overlay of the Fab-MET crystal structure with the InternalinB-MET crystal structure shows that the 107_A07 Fab comes into close proximity with the HGF/SF-binding SEMA domain when MET is in the “compact”, InternalinB-bound conformation, but not when MET is in the “open” conformation. These findings provide further support for the importance of the “compact” conformation of the MET extracellular domain, and the relevance of this conformation to HGF/SF binding and signaling.
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Affiliation(s)
- Danielle M DiCara
- MRC Centre, Hills Road, Cambridge, CB2 2QH, UK.,Department of Oncology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XZ, UK.,Genentech Inc., South San Francisco, 94080, USA
| | - Dimitri Y Chirgadze
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Anthony R Pope
- IONTAS Ltd, Babraham Institute, Babraham, Cambridgeshire, CB22 3AT, UK
| | | | - Anja Winter
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK.,Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, UK
| | - Peter Slavny
- IONTAS Ltd, Babraham Institute, Babraham, Cambridgeshire, CB22 3AT, UK
| | - Joop van den Heuvel
- Helmholtz Zentrum für Infektionsforschung, Inhoffenstraße 7, 38124, Braunschweig, Germany
| | - Kothai Parthiban
- IONTAS Ltd, Babraham Institute, Babraham, Cambridgeshire, CB22 3AT, UK
| | - Jane Holland
- Max Delbrueck Center for Molecular Medicine (MDC) in the Helmholtz Association, 13125, Berlin, Germany
| | - Len C Packman
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Georgia Mavria
- Leeds Institute of Cancer and Pathology, University of Leeds, St James' University Hospital, Beckett Street, Leeds, LS9 7TF, UK
| | - Jens Hoffmann
- Experimental Pharmacology & Oncology Berlin-Buch GmbH, Robert-Rössle-Str. 10, 13125, Berlin-Buch, Germany
| | - Walter Birchmeier
- Max Delbrueck Center for Molecular Medicine (MDC) in the Helmholtz Association, 13125, Berlin, Germany
| | - Ermanno Gherardi
- MRC Centre, Hills Road, Cambridge, CB2 2QH, UK. .,Department of Oncology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XZ, UK. .,Division of Immunology and General Pathology, Department of Molecular Medicine, 1 via A Ferrata, 27100, Pavia, Italy.
| | - John McCafferty
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK. .,IONTAS Ltd, Babraham Institute, Babraham, Cambridgeshire, CB22 3AT, UK.
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30
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Arola HO, Tullila A, Nathanail AV, Nevanen TK. A Simple and Specific Noncompetitive ELISA Method for HT-2 Toxin Detection. Toxins (Basel) 2017; 9:E145. [PMID: 28425967 PMCID: PMC5408219 DOI: 10.3390/toxins9040145] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/13/2017] [Accepted: 04/14/2017] [Indexed: 11/16/2022] Open
Abstract
We developed an HT-2 toxin-specific simple ELISA format with a positive read-out. The assay is based on an anti-immune complex (IC) scFv antibody fragment, which is genetically fused with alkaline phosphatase (AP). The anti-IC antibody specifically recognizes the IC between a primary anti-HT-2 toxin Fab fragment and an HT-2 toxin molecule. In the IC ELISA format, the sample is added together with the scFv-AP antibody to the ELISA plate coated with the primary antibody. After 15 min of incubation and a washing step, the ELISA response is read. A competitive ELISA including only the primary antibody recognizes both HT-2 and T-2 toxins. The anti-IC antibody makes the assay specific for HT-2 toxin, and the IC ELISA is over 10 times more sensitive compared to the competitive assay. Three different naturally contaminated matrices: wheat, barley and oats, were used to evaluate the assay performance with real samples. The corresponding limits of detection were 0.3 ng/mL (13 µg/kg), 0.1 ng/mL (4 µg/kg) and 0.3 ng/mL (16 µg/kg), respectively. The IC ELISA can be used for screening HT-2 toxin specifically and in relevant concentration ranges from all three tested grain matrices.
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Affiliation(s)
- Henri O Arola
- VTT Technical Research Centre of Finland, Tietotie 2 FI-02150 Espoo, Finland.
| | - Antti Tullila
- VTT Technical Research Centre of Finland, Tietotie 2 FI-02150 Espoo, Finland.
| | - Alexis V Nathanail
- Finnish Food Safety Authority (Evira), Chemistry and Toxicology Unit, Research and Laboratory Department, Mustialankatu 3, FI-00790 Helsinki, Finland.
| | - Tarja K Nevanen
- VTT Technical Research Centre of Finland, Tietotie 2 FI-02150 Espoo, Finland.
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31
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Drosopoulos WC, Kosiyatrakul ST, Schildkraut CL. BLM helicase facilitates telomere replication during leading strand synthesis of telomeres. J Cell Biol 2016. [PMID: 26195664 PMCID: PMC4508891 DOI: 10.1083/jcb.201410061] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BLM helicase facilitates telomere replication by resolving G-quadruplex structures that can form in the G-rich repeats during leading strand synthesis. Based on its in vitro unwinding activity on G-quadruplex (G4) DNA, the Bloom syndrome–associated helicase BLM is proposed to participate in telomere replication by aiding fork progression through G-rich telomeric DNA. Single molecule analysis of replicated DNA (SMARD) was used to determine the contribution of BLM helicase to telomere replication. In BLM-deficient cells, replication forks initiating from origins within the telomere, which copy the G-rich strand by leading strand synthesis, moved slower through the telomere compared with the adjacent subtelomere. Fork progression through the telomere was further slowed in the presence of a G4 stabilizer. Using a G4-specific antibody, we found that deficiency of BLM, or another G4-unwinding helicase, the Werner syndrome-associated helicase WRN, resulted in increased G4 structures in cells. Importantly, deficiency of either helicase led to greater increases in G4 DNA detected in the telomere compared with G4 seen genome-wide. Collectively, our findings are consistent with BLM helicase facilitating telomere replication by resolving G4 structures formed during copying of the G-rich strand by leading strand synthesis.
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Affiliation(s)
| | | | - Carl L Schildkraut
- Department of Cell Biology, Albert Einstein College of Medicine, New York, NY 10461
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32
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Rif1 binds to G quadruplexes and suppresses replication over long distances. Nat Struct Mol Biol 2015; 22:889-97. [PMID: 26436827 DOI: 10.1038/nsmb.3102] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 09/03/2015] [Indexed: 12/20/2022]
Abstract
Rif1 regulates replication timing and repair of double-strand DNA breaks. Using a chromatin immunoprecipitation-sequencing method, we identified 35 high-affinity Rif1-binding sites in fission yeast chromosomes. Binding sites tended to be located near dormant origins and to contain at least two copies of a conserved motif, CNWWGTGGGGG. Base substitution within these motifs resulted in complete loss of Rif1 binding and in activation of late-firing or dormant origins located up to 50 kb away. We show that Rif1-binding sites adopt G quadruplex-like structures in vitro, in a manner dependent on the conserved sequence and on other G tracts, and that purified Rif1 preferentially binds to this structure. These results suggest that Rif1 recognizes and binds G quadruplex-like structures at selected intergenic regions, thus generating local chromatin structures that may exert long-range suppressive effects on origin firing.
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Ossysek K, Uchański T, Kulesza M, Bzowska M, Klaus T, Woś K, Madej M, Bereta J. A new expression vector facilitating production and functional analysis of scFv antibody fragments selected from Tomlinson I + J phagemid libraries. Immunol Lett 2015. [DOI: 10.1016/j.imlet.2015.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Yang S, Shang Y, Yin S, Wang D, Cai J, Gong Z, Serge M, Liu X. A phage-displayed single domain antibody fused to alkaline phosphatase for detection of porcine circovirus type 2. J Virol Methods 2015; 213:84-92. [DOI: 10.1016/j.jviromet.2014.11.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 11/26/2014] [Accepted: 11/28/2014] [Indexed: 10/24/2022]
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Patil NA, Tailhades J, Hughes RA, Separovic F, Wade JD, Hossain MA. Cellular disulfide bond formation in bioactive peptides and proteins. Int J Mol Sci 2015; 16:1791-805. [PMID: 25594871 PMCID: PMC4307334 DOI: 10.3390/ijms16011791] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/02/2015] [Indexed: 11/16/2022] Open
Abstract
Bioactive peptides play important roles in metabolic regulation and modulation and many are used as therapeutics. These peptides often possess disulfide bonds, which are important for their structure, function and stability. A systematic network of enzymes--a disulfide bond generating enzyme, a disulfide bond donor enzyme and a redox cofactor--that function inside the cell dictates the formation and maintenance of disulfide bonds. The main pathways that catalyze disulfide bond formation in peptides and proteins in prokaryotes and eukaryotes are remarkably similar and share several mechanistic features. This review summarizes the formation of disulfide bonds in peptides and proteins by cellular and recombinant machinery.
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Affiliation(s)
- Nitin A Patil
- Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Victoria 3010, Australia.
| | - Julien Tailhades
- Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Victoria 3010, Australia.
| | - Richard Anthony Hughes
- Department of Pharmacology and Therapeutics, the University of Melbourne, Victoria 3010, Australia.
| | - Frances Separovic
- School of Chemistry, the University of Melbourne, Victoria 3010, Australia.
| | - John D Wade
- Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Victoria 3010, Australia.
| | - Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Victoria 3010, Australia.
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Genetic methods of antibody generation and their use in immunohistochemistry. Methods 2014; 70:20-7. [DOI: 10.1016/j.ymeth.2014.02.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 01/22/2014] [Accepted: 02/21/2014] [Indexed: 12/18/2022] Open
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Cuozzo JW, Soutter HH. Overview of Recent Progress in Protein-Expression Technologies for Small-Molecule Screening. ACTA ACUST UNITED AC 2014; 19:1000-13. [PMID: 24525871 DOI: 10.1177/1087057114520975] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 01/02/2014] [Indexed: 01/09/2023]
Abstract
Production of novel soluble and membrane-localized protein targets for functional and affinity-based screening has often been limited by the inability of traditional protein-expression systems to generate recombinant proteins that have properties similar to those of their endogenous counterparts. Such targets have often been labeled as challenging. Although biological validation of these challenging targets for specific disease areas may be strong, discovery of small-molecule modulators can be greatly delayed or completely halted due to target-expression issues. In this article, the limitations of traditional protein-expression systems will be discussed along with new systems designed to overcome these challenges. Recent work in this field has focused on two major areas for both soluble and membrane targets: construct-design strategies to improve expression levels and new hosts that can carry out the posttranslational modifications necessary for proper target folding and function. Another area of active research has been on the reconstitution of solubilized membrane targets for both structural analysis and screening. Finally, the potential impact of these new systems on the output of small-molecule screening campaigns will be discussed.
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Falk R, Falk A, Dyson MR, Melidoni AN, Parthiban K, Young JL, Roake W, McCafferty J. Generation of anti-Notch antibodies and their application in blocking Notch signalling in neural stem cells. Methods 2012; 58:69-78. [PMID: 22842086 PMCID: PMC3502869 DOI: 10.1016/j.ymeth.2012.07.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 07/11/2012] [Indexed: 01/24/2023] Open
Abstract
Notch signalling occurs via direct cell–cell interactions and plays an important role in linking the fates of neighbouring cells. There are four different mammalian Notch receptors that can be activated by five cell surface ligands. The ability to inhibit specific Notch receptors would help identify the roles of individual family members and potentially provide a means to study and control cell differentiation. Anti-Notch antibodies in the form of single chain Fvs were generated from an antibody phage display library by selection on either the ligand binding domain or the negative regulatory region (NRR) of Notch1 and Notch2. Six antibodies targeting the NRR of Notch1 and four antibodies recognising the NRR of Notch2 were found to prevent receptor activation in cell-based luciferase reporter assays. These antibodies were potent, highly specific inhibitors of individual Notch receptors and interfered with endogenous signalling in stem cell systems of both human and mouse origin. Antibody-mediated inhibition of Notch efficiently down-regulated transcription of the immediate Notch target gene hairy and enhancer of split 5 (Hes5) in both mouse and human neural stem cells and revealed a redundant regulation of Hes5 in these cells as complete down-regulation was seen only after simultaneous blocking of Notch1 and Notch2. In addition, these antibodies promoted differentiation of neural stem cells towards a neuronal fate. In contrast to the widely used small molecule γ-secretase inhibitors, which block all 4 Notch receptors (and a multitude of other signalling pathways), antibodies allow blockade of individual Notch family members in a highly specific way. Specific inhibition will allow examination of the effect of individual Notch receptors in complex differentiation schemes regulated by the co-ordinated action of multiple signalling pathways.
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Affiliation(s)
- Ronny Falk
- University of Cambridge, Department of Biochemistry, Tennis Court Road, CB2 1QW Cambridge, UK
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de Marco A. Methodologies for the isolation of alternative binders with improved clinical potentiality over conventional antibodies. Crit Rev Biotechnol 2012; 33:40-8. [PMID: 22475460 DOI: 10.3109/07388551.2012.665353] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The availability of binders to different functional domains of the same protein or to physiologically co-operating proteins allows for the simultaneous inhibition of independent downstream signaling pathways. This multi-target approach represents a promising therapeutic strategy, as demonstrated in the case of the synergistic effect of anti-Her2 treatment based on the combined use of the trastuzumab and pertuzumab monoclonal antibodies that induce cellular cytotoxicity and impair the receptor dimerization, respectively. Therefore, a reliable selection method for the recovery of epitope-specific antibodies is highly needed. Animal immunization with short peptides resembling the epitope sequence for raising conventional antibodies represents an alternative. Panning phage displayed libraries of recombinant antibodies such as scFvs and nanobodies or of other peptide collections is another option. Although recombinant antibodies can provide the same specificity as conventional antibodies, they offer at least two further advantages: i) the protocols for the selection of epitope-specific antibodies can be rationally designed, and ii) their expression as multivalent, bispecific and biparatopic molecules is feasible. This review will analyze the recent literature concerning technical aspects related to the isolation, the expression as multivalent molecules, and the therapeutic applications of binders able to interfere with antigen functional domains. The term binder will be preferred when possible to include those molecules, such as peptides or affibodies, with at least some proven practical uses.
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Affiliation(s)
- Ario de Marco
- University of Nova Gorica (UNG), Rožna Dolina (Nova Gorica), Slovenia.
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Ahmad ZA, Yeap SK, Ali AM, Ho WY, Alitheen NBM, Hamid M. scFv antibody: principles and clinical application. Clin Dev Immunol 2012; 2012:980250. [PMID: 22474489 PMCID: PMC3312285 DOI: 10.1155/2012/980250] [Citation(s) in RCA: 475] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 01/07/2012] [Indexed: 01/16/2023]
Abstract
To date, generation of single-chain fragment variable (scFv) has become an established technique used to produce a completely functional antigen-binding fragment in bacterial systems. The advances in antibody engineering have now facilitated a more efficient and generally applicable method to produce Fv fragments. Basically, scFv antibodies produced from phage display can be genetically fused to the marker proteins, such as fluorescent proteins or alkaline phosphatase. These bifunctional proteins having both antigen-binding capacity and marker activity can be obtained from transformed bacteria and used for one-step immunodetection of biological agents. Alternatively, antibody fragments could also be applied in the construction of immunotoxins, therapeutic gene delivery, and anticancer intrabodies for therapeutic purposes. This paper provides an overview of the current studies on the principle, generation, and application of scFv. The potential of scFv in breast cancer research is also discussed in this paper.
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Affiliation(s)
- Zuhaida Asra Ahmad
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Selangor, 43400 Serdang, Malaysia
| | - Swee Keong Yeap
- Institute of Bioscience, Universiti Putra Malaysia, Selangor, 43400 Serdang, Malaysia
| | - Abdul Manaf Ali
- Faculty of Agriculture and Biotechnology, Universiti Sultan Zainal Abidin, Kampus Kota, Jalan Sultan Mahmud, 20400 Kuala Terengganu, Malaysia
| | - Wan Yong Ho
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Selangor, 43400 Serdang, Malaysia
| | - Noorjahan Banu Mohamed Alitheen
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Selangor, 43400 Serdang, Malaysia
| | - Muhajir Hamid
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Selangor, 43400 Serdang, Malaysia
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Selangor, 43400 Serdang, Malaysia
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Sun W, Xie J, Lin H, Mi S, Li Z, Hua F, Hu Z. A combined strategy improves the solubility of aggregation-prone single-chain variable fragment antibodies. Protein Expr Purif 2012; 83:21-9. [PMID: 22387083 DOI: 10.1016/j.pep.2012.02.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Revised: 02/03/2012] [Accepted: 02/08/2012] [Indexed: 02/03/2023]
Abstract
Recombinant single-chain variable fragment (scFv) antibodies have wide applications in the areas of biotechnology and medicine. However, there is currently no universal expression-purification system for generating different soluble scFvs. In this study, A15 and E34, two genes coding scFvs against human IL-17A, were fused with N-terminal signal peptide sequences pelB or STII, or with highly hydrophilic tags Trx, NusA, or MBP, respectively. These constructs were expressed in Escherichia coli. We found that the scFvs fused with either NusA or MBP showed a higher solubility than fused with signal peptides or Trx. The scFvs were aggregated when the NusA or MBP was removed by thrombin. Interestingly, we observed a reduction of precipitation when the fusion proteins were expressed in Origami B(DE3)pLysS cells but not in BL21(DE3)pLysS. Because cleaving the tags resulted in the aggregation of scFvs, several solubility-enhancing additives were added in the digestion buffer and only L-arginine (Arg) or Tween20 promoted the solubility. After an affinity chromatography, the scFvs were separated from the tags with the purity up to 90%. The final yield of scFvs from the scFv-MBP system was approximately 8.9 mg/L of culture medium and 1.5 mg/g of wet weight cells, which was 1.6-fold higher than the yield from the scFv-NusA system. The obtained scFvs exhibited normal binding affinities and activities after endotoxin removal. In conclusion, we describe a strategy combining the fusion tags, the Escherichia coli with oxidizing bacterial cytoplasm, and the solubility-enhancing additives for expressing and purifying the soluble and functional scFvs.
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Affiliation(s)
- Wei Sun
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China
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Tang J, Wang L, Markiv A, Jeffs SA, Dreja H, McKnight Á, He M, Kang AS. Accessing of recombinant human monoclonal antibodies from patient libraries by eukaryotic ribosome display. Hum Antibodies 2012; 21:1-11. [PMID: 22885956 PMCID: PMC3677101 DOI: 10.3233/hab-2011-0257] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
What are effective antibodies and when do they arise to prevent or delay disease onset during a natural infection or in the course of vaccination? To address these questions at a molecular level requires longitudinal studies, capturing and analyzing the antibody repertoire at regular intervals following exposure or sero-conversion. Such studies require a method that allows the rapid generation and evaluation of monoclonal antibodies from relatively small volumes of blood. Here we describe an approach for rapidly generating human monoclonal antibodies in vitro by directly screening single-chain antibody repertories derived from donor peripheral blood mononuclear cells using ribosome display. Two single-chain antibody libraries were constructed using RNA extracted from peripheral blood mononuclear cells of two HIV-1 long-term non-progressor donors (K530 and M325). Both libraries were subjected to a single round of in vitro ribosome display for enrichment of human monoclonal antibodies against recombinant gp120(K530), derived from virus isolated from donor K530. This study has validated a novel, in vitro method for the rapid generation of human monoclonal antibodies. An antibody library could be constructed from as little as 3 μg of total RNA, the equivalent of 3-5 mL of human blood.
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Affiliation(s)
- Jie Tang
- Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China
- School of Life Sciences, University of Westminster, London, UK
| | - Lin Wang
- School of Life Sciences, University of Westminster, London, UK
- Institute of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan, China
| | - Anatoliy Markiv
- School of Life Sciences, University of Westminster, London, UK
| | - Simon A. Jeffs
- Wright-Fleming Institute, Division of Medicine, Imperial College London, Norfolk Place, London, UK
| | - Hanna Dreja
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, Whitechapel, London, UK
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Áine McKnight
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, Whitechapel, London, UK
| | - Mingyue He
- The Inositide Laboratory, Babraham Institute, Cambridge, UK
| | - Angray S. Kang
- School of Life Sciences, University of Westminster, London, UK
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, Whitechapel, London, UK
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Dyson MR, Zheng Y, Zhang C, Colwill K, Pershad K, Kay BK, Pawson T, McCafferty J. Mapping protein interactions by combining antibody affinity maturation and mass spectrometry. Anal Biochem 2011; 417:25-35. [PMID: 21704603 PMCID: PMC3171153 DOI: 10.1016/j.ab.2011.05.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 03/27/2011] [Accepted: 05/03/2011] [Indexed: 12/24/2022]
Abstract
Mapping protein interactions by immunoprecipitation is limited by the availability of antibodies recognizing available native epitopes within protein complexes with sufficient affinity. Here we demonstrate a scalable approach for generation of such antibodies using phage display and affinity maturation. We combined antibody variable heavy (V(H)) genes from target-specific clones (recognizing Src homology 2 (SH2) domains of LYN, VAV1, NCK1, ZAP70, PTPN11, CRK, LCK, and SHC1) with a repertoire of 10(8) to 10(9) new variable light (V(L)) genes. Improved binders were isolated by stringent selections from these new "chain-shuffled" libraries. We also developed a predictive 96-well immunocapture screen and found that only 12% of antibodies had sufficient affinity/epitope availability to capture endogenous target from lysates. Using antibodies of different affinities to the same epitope, we show that affinity improvement was a key determinant for success and identified a clear affinity threshold value (60 nM for SHC1) that must be breached for success in immunoprecipitation. By combining affinity capture using matured antibodies to SHC1 with mass spectrometry, we identified seven known binding partners and two known SHC1 phosphorylation sites in epidermal growth factor (EGF)-stimulated human breast cancer epithelial cells. These results demonstrate that antibodies capable of immunoprecipitation can be generated by chain shuffling, providing a scalable approach to mapping protein-protein interaction networks.
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Affiliation(s)
- Michael R. Dyson
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Yong Zheng
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
| | - Cunjie Zhang
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
| | - Karen Colwill
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
| | - Kritika Pershad
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Brian K. Kay
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Tony Pawson
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
- Department of Molecular and Medical Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - John McCafferty
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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Swain MD, Anderson GP, Serrano-González J, Liu JL, Zabetakis D, Goldman ER. Immunodiagnostic reagents using llama single domain antibody–alkaline phosphatase fusion proteins. Anal Biochem 2011; 417:188-94. [DOI: 10.1016/j.ab.2011.06.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 06/02/2011] [Accepted: 06/08/2011] [Indexed: 01/22/2023]
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An anti-Aβ (amyloid β) single-chain variable fragment prevents amyloid fibril formation and cytotoxicity by withdrawing Aβ oligomers from the amyloid pathway. Biochem J 2011; 437:25-34. [DOI: 10.1042/bj20101712] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Aβ (amyloid β) immunotherapy has been revealed as a possible tool in Alzheimer's disease treatment. In contrast with complete antibodies, the administration of scFvs (single-chain variable fragments) produces neither meningoencephalitis nor cerebral haemorrhage. In the present study, the recombinant expression of scFv-h3D6, a derivative of an antibody specific for Aβ oligomers, is presented, as well as the subsequent proof of its capability to recover the toxicity induced by the Aβ1–42 peptide in the SH-SY5Y neuroblastoma cell line. To gain insight into the conformational changes underlying the prevention of Aβ toxicity by this antibody fragment, the conformational landscape of scFv-h3D6 upon temperature perturbation is also described. Heating the native state does not lead to any extent of unfolding, but rather directly to a β-rich intermediate state which initiates an aggregation pathway. This aggregation pathway is not an amyloid fibril pathway, as is that followed by the Aβ peptide, but rather a worm-like fibril pathway which, noticeably, turns out to be non-toxic. On the other hand, this pathway is thermodynamically and kinetically favoured when the scFv-h3D6 and Aβ1–42 oligomers form a complex in native conditions, explaining how the scFv-h3D6 withdraws Aβ1–42 oligomers from the amyloid pathway. To our knowledge, this is the first description of a conformational mechanism by which a scFv prevents Aβ-oligomer cytotoxicity.
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47
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Colwill K, Gräslund S. A roadmap to generate renewable protein binders to the human proteome. Nat Methods 2011; 8:551-8. [PMID: 21572409 DOI: 10.1038/nmeth.1607] [Citation(s) in RCA: 237] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 04/11/2011] [Indexed: 12/16/2022]
Abstract
Despite the wealth of commercially available antibodies to human proteins, research is often hindered by their inconsistent validation, their poor performance and the inadequate coverage of the proteome. These issues could be addressed by systematic, genome-wide efforts to generate and validate renewable protein binders. We report a multicenter study to assess the potential of hybridoma and phage-display technologies in a coordinated large-scale antibody generation and validation effort. We produced over 1,000 antibodies targeting 20 SH2 domain proteins and evaluated them for potency and specificity by enzyme-linked immunosorbent assay (ELISA), protein microarray and surface plasmon resonance (SPR). We also tested selected antibodies in immunoprecipitation, immunoblotting and immunofluorescence assays. Our results show that high-affinity, high-specificity renewable antibodies generated by different technologies can be produced quickly and efficiently. We believe that this work serves as a foundation and template for future larger-scale studies to create renewable protein binders.
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Affiliation(s)
- Karen Colwill
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
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48
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Song Y, Antoniou C, Memic A, Kay BK, Fung LWM. Apparent structural differences at the tetramerization region of erythroid and nonerythroid beta spectrin as discriminated by phage displayed scFvs. Protein Sci 2011; 20:867-79. [PMID: 21412925 DOI: 10.1002/pro.617] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 01/25/2011] [Accepted: 02/28/2011] [Indexed: 01/26/2023]
Abstract
We have screened a human immunoglobulin single-chain variable fragment (scFv) phage library against the C-terminal tetramerization regions of erythroid and nonerythroid beta spectrin (βI-C1 and βII-C1, respectively) to explore the structural uniqueness of erythroid and nonerythroid β-spectrin isoforms. We have identified interacting scFvs, with clones "G5" and "A2" binding only to βI-C1, and clone "F11" binding only to βII-C1. The K(d) values, estimated by competitive enzyme-linked immunosorbent assay, of these scFvs with their target spectrin proteins were 0.1-0.3 μM. A more quantitative K(d) value from isothermal titration calorimetry experiments with the recombinant G5 and βI-C1 was 0.15 μM. The α-spectrin fragments (model proteins), αI-N1 and αII-N1, competed with the βI-C1, or βII-C1, binding scFvs, with inhibitory concentration (IC(50) ) values of ∼50 μM for αI-N1, and ∼0.5 μM for αII-N1. Our predicted structures of βI-C1 and βII-C1 suggest that the Helix B' of the C-terminal partial domain of βI differs from that of βII. Consequently, an unstructured region downstream of Helix B' in βI may interact specifically with the unstructured, complementarity determining region H1 of G5 or A2 scFv. The corresponding region in βII was helical, and βII did not bind G5 scFv. Our results suggest that it is possible for cellular proteins to differentially associate with the C-termini of different β-spectrin isoforms to regulate α- and β-spectrin association to form functional spectrin tetramers, and may sort β-spectrin isoforms to their specific cellular localizations.
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Affiliation(s)
- Yuanli Song
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA
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49
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Abstract
Proteolytic release from the cell surface is an essential activation event for many growth factors and cytokines. TNF-α converting enzyme (TACE) is a membrane-bound metalloprotease responsible for solubilizing many pathologically significant membrane substrates and is an attractive therapeutic target for the treatment of cancer and arthritis. Prior attempts to antagonize cell-surface TACE activity have focused on small-molecule inhibition of the metalloprotease active site. Given the highly conserved nature of metalloprotease active sites, this paradigm has failed to produce a truly specific TACE inhibitor and continues to obstruct the clinical investigation of TACE activity. We report the bespoke development of a specific TACE inhibitory human antibody using "two-step" phage display. This approach combines calculated selection conditions with antibody variable-domain exchange to direct individual antibody variable domains to desired epitopes. The resulting "cross-domain" human antibody is a previously undescribed selective TACE antagonist and provides a unique alternative to small-molecule metalloprotease inhibition.
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50
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Pershad K, Sullivan MA, Kay BK. Drop-out phagemid vector for switching from phage displayed affinity reagents to expression formats. Anal Biochem 2011; 412:210-6. [PMID: 21315061 DOI: 10.1016/j.ab.2011.02.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 02/02/2011] [Accepted: 02/03/2011] [Indexed: 12/26/2022]
Abstract
Affinity reagents that are generated by phage display are typically subcloned into an expression vector for further biochemical characterization. This insert transfer process is time consuming and laborious especially if many inserts are to be subcloned. To simplify the transfer process, we have constructed a "drop-out" phagemid vector that can be rapidly converted to an expression vector by a simple restriction enzyme digestion with MfeI (to "drop-out" the gene III coding sequence), which generates alkaline phosphatase (AP) fusions of the affinity reagents on religation. Subsequently, restriction digestion with AscI drops out the AP coding region and religation generates affinity reagents with a C-terminal six-histidine tag. To validate the usefulness of this vector, four different human single chain Fragments of variable regions (scFv) were tested, three of which show specific binding to three zebrafish (Danio rerio) proteins, namely suppression of tumorigenicity 13, recoverin, and Ppib and the fourth binds to human Lactoferrin protein. For each of the constructs tested, the gene III and AP drop-out efficiency was between 90% and 100%. This vector is especially useful in speeding up the downstream screening of affinity reagents and bypassing the time-consuming subcloning experiments.
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Affiliation(s)
- Kritika Pershad
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Avenue, Molecular Biology Research Building, Room 4318, Laboratory for Molecular Biology (M/C 567), Chicago, IL 60607, USA
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