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Zhang Y, Zhang Y, Zhang L, Liu Y. Oriented immobilization of nanobodies using SpyCatcher/SpyTag significantly enhances the capacity of affinity chromatography. J Chromatogr A 2024; 1730:465107. [PMID: 38905946 DOI: 10.1016/j.chroma.2024.465107] [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: 03/04/2024] [Revised: 06/14/2024] [Accepted: 06/17/2024] [Indexed: 06/23/2024]
Abstract
The use of nanobodies (Nbs) in affinity chromatography for biomacromolecule purification is gaining popularity. However, high-performance Nb-based affinity resins are not readily available, mainly due to the lack of suitable immobilization methods. In this study, we explored an autocatalytic coupling strategy based on the SpyCatcher/SpyTag chemistry to achieve oriented immobilization of Nb ligands. To facilitate this approach, a variant cSpyCatcher003 (cSC003) was coupled onto agarose microspheres, providing a specific attachment site for SpyTagged nanobody ligands. The cSC003 easily purified from Escherichia coli through a two-step procedure, exhibits exceptional alkali resistance and structural recovery capability, highlighting its robustness as a linker in the coupling strategy. To validate the effectiveness of cSC003-derivatized support, we employed VHSA, a nanobody against human serum albumin (HSA), as the model ligand. Notably, the immobilization of SpyTagged VHSA onto the cSC003-derivatized support was achieved with a coupling efficiency of 90 %, significantly higher than that of traditional thiol-based coupling method. This improvement directly correlated to the preservation of the native conformation of nanobodies during the coupling process. In addition, the Spy-immobilized resin demonstrated better performance in the binding capacity, with a 3-fold improvement in capture efficiency, underscoring the advantages of the Spy immobilization strategy for oriented immobilization of VHSA ligands. Moreover, online purification and immobilization of SpyTagged VHSA from crude bacterial lysate was achieved using the cSC003-derivatized support. The resulting resin exhibited high binding specificity towards HSA, yielding a purity above 95 % directly from human serum, and maintained good stability throughout multiple purification cycles. These findings highlight the potential of the Spy immobilization strategy for developing Nb-based affinity chromatographic materials, with significant implications for biopharmaceutical downstream processes.
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Affiliation(s)
- Yuxiang Zhang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yao Zhang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China
| | - Luyao Zhang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yongdong Liu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China.
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2
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Sherwood LJ, Hayhurst A. Generating Uniformly Cross-Reactive Ebolavirus spp. Anti-nucleoprotein Nanobodies to Facilitate Forward Capable Detection Strategies. ACS Infect Dis 2022; 8:343-359. [PMID: 34994194 DOI: 10.1021/acsinfecdis.1c00478] [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: 11/30/2022]
Abstract
It is often challenging for a single monoclonal antibody to cross-react equally with all species of a particular viral genus that are separated by time and geographies to ensure broad long-term global immunodiagnostic use. Here, we set out to isolate nanobodies or single-domain antibodies (sdAbs) with uniform cross-reactivity to the genus Ebolavirus by immunizing a llama with recombinant nucleoprotein (NP) representing the 5 cultivated species to assemble a phage display repertoire for mining. Screening sdAbs for reactivity against the C-terminal domain of NP guided the isolation of clones that could perform as both captor and tracer for polyvalent antigen in sandwich assays. Two promising sdAbs had equivalent reactivities across all 5 species and greatly enhanced the equilibrium concentration at 50% (EC50) for recombinant NP when compared with a differentially cross-reactive nonimmune sdAb isolated previously. Uniform reactivity and enhanced sensitivity were relayed to live virus titrations, resulting in lower limits of detection of 2-5 pfu for the best sdAbs, representing 10-, 20-, and 100-fold improvements for Zaire, Sudan/Reston, and Taï Forest viruses, respectively. Fusions of the sdAbs with ascorbate peroxidase (APEX2) and mNeonGreen generated one-step immunoreagents useful for colorimetric and fluorescent visualization of cellular NP. Both sdAbs were also able to recognize recombinant NPs from the recently discovered Bombali virus, a putative sixth Ebolavirus species unknown at the start of these experiments, validating the forward capabilities of the sdAbs. The simplicity and modularity of these sdAbs should enable advances in antigen-based diagnostic technologies to be retuned toward filoviral detection relatively easily, thereby proactively safeguarding human health.
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Affiliation(s)
- Laura Jo Sherwood
- Disease Intervention and Prevention, Texas Biomedical Research Institute, San Antonio, Texas 78227, United States
| | - Andrew Hayhurst
- Disease Intervention and Prevention, Texas Biomedical Research Institute, San Antonio, Texas 78227, United States
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3
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Gao S, Guisán JM, Rocha-Martin J. Oriented immobilization of antibodies onto sensing platforms - A critical review. Anal Chim Acta 2022; 1189:338907. [PMID: 34815045 DOI: 10.1016/j.aca.2021.338907] [Citation(s) in RCA: 70] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/08/2021] [Accepted: 07/31/2021] [Indexed: 12/26/2022]
Abstract
The immunosensor has been proven a versatile tool to detect various analytes, such as food contaminants, pathogenic bacteria, antibiotics and biomarkers related to cancer. To fabricate robust and reproducible immunosensors with high sensitivity, the covalent immobilization of immunoglobulins (IgGs) in a site-specific manner contributes to better performance. Instead of the random IgG orientations result from the direct yet non-selective immobilization techniques, this review for the first time introduces the advances of stepwise yet site-selective conjugation strategies to give better biosensing efficiency. Noncovalently adsorbing IgGs is the first but decisive step to interact specifically with the Fc fragment, then following covalent conjugate can fix this uniform and antigens-favorable orientation irreversibly. In this review, we first categorized this stepwise strategy into two parts based on the different noncovalent interactions, namely adhesive layer-mediated interaction onto homofunctional support and layer-free interaction onto heterofunctional support (which displays several different functionalities on its surface that are capable to interact with IgGs). Further, the influence of ligands characteristics (synthesis strategies, spacer requirements and matrices selection) on the heterofunctional support has also been discussed. Finally, conclusions and future perspectives for the real-world application of stepwise covalent conjugation are discussed. This review provides more insights into the fabrication of high-efficiency immunosensor, and special attention has been devoted to the well-orientation of full-length IgGs onto the sensing platform.
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Affiliation(s)
- Shipeng Gao
- Department of Biocatalysis, Institute of Catalysis and Petrochemistry (ICP) CSIC, Campus UAM, Cantoblanco, 28049, Madrid, Spain
| | - José M Guisán
- Department of Biocatalysis, Institute of Catalysis and Petrochemistry (ICP) CSIC, Campus UAM, Cantoblanco, 28049, Madrid, Spain.
| | - Javier Rocha-Martin
- Department of Biocatalysis, Institute of Catalysis and Petrochemistry (ICP) CSIC, Campus UAM, Cantoblanco, 28049, Madrid, Spain.
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4
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Selection and Characterization of Single-Domain Antibodies for Detection of Lassa Nucleoprotein. Antibodies (Basel) 2020; 9:antib9040071. [PMID: 33348599 PMCID: PMC7768477 DOI: 10.3390/antib9040071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 11/26/2022] Open
Abstract
Lassa virus is the etiologic agent of Lassa fever, an acute and often fatal illness endemic to West Africa. It is important to develop new reagents applicable either for the specific diagnosis or as improved therapeutics for the treatment of Lassa fever. Here, we describe the development and initial testing of llama-derived single-domain antibodies that are specific for the Lassa virus nucleoprotein. Four sequence families based on complementarity-determining region (CDR) homology were identified by phage-based enzyme-linked immunosorbent assays, however, the highest affinity clones all belonged to the same sequence family which possess a second disulfide bond between Framework 2 and CDR3. The affinity and thermal stability were evaluated for each clone. A MagPlex-based homogeneous sandwich immunoassay for Lassa virus-like particles was also demonstrated to show their potential for further development as diagnostic reagents.
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5
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Ford NR, Xiong Y, Hecht KA, Squier TC, Rorrer GL, Roesijadi G. Optimizing the Design of Diatom Biosilica-Targeted Fusion Proteins in Biosensor Construction for Bacillus anthracis Detection. BIOLOGY 2020; 9:biology9010014. [PMID: 31936120 PMCID: PMC7168173 DOI: 10.3390/biology9010014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 12/24/2019] [Accepted: 01/04/2020] [Indexed: 11/16/2022]
Abstract
In vivo functionalization of diatom biosilica frustules by genetic manipulation requires careful consideration of the overall structure and function of complex fusion proteins. Although we previously had transformed Thalassiosira pseudonana with constructs containing a single domain antibody (sdAb) raised against the Bacillus anthracis Sterne strain, which detected an epitope of the surface layer protein EA1 accessible in lysed spores, we initially were unsuccessful with constructs encoding a similar sdAb that detected an epitope of EA1 accessible in intact spores and vegetative cells. This discrepancy limited the usefulness of the system as an environmental biosensor for B. anthracis. We surmised that to create functional biosilica-localized biosensors with certain constructs, the biosilica targeting and protein trafficking functions of the biosilica-targeting peptide Sil3T8 had to be uncoupled. We found that retaining the ER trafficking sequence at the N-terminus and relocating the Sil3T8 targeting peptide to the C-terminus of the fusion protein resulted in successful detection of EA1 with both sdAbs. Homology modeling of antigen binding by the two sdAbs supported the hypothesis that the rescue of antigen binding in the previously dysfunctional sdAb was due to removal of steric hindrances between the antigen binding loops and the diatom biosilica for that particular sdAb.
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Affiliation(s)
- Nicole R. Ford
- Marine Biotechnology Group, Pacific Northwest National Laboratory, Sequim, WA 98382, USA
- Correspondence:
| | - Yijia Xiong
- Department of Basic Medical Sciences, Western University of Health Sciences, Lebanon, OR 97355, USA
| | - Karen A. Hecht
- Marine Biotechnology Group, Pacific Northwest National Laboratory, Sequim, WA 98382, USA
| | - Thomas C. Squier
- Department of Basic Medical Sciences, Western University of Health Sciences, Lebanon, OR 97355, USA
| | - Gregory L. Rorrer
- School of Chemical Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, USA
| | - Guritno Roesijadi
- Marine Biotechnology Group, Pacific Northwest National Laboratory, Sequim, WA 98382, USA
- School of Chemical Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, USA
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6
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Anderson GP, Liu JL, Shriver-Lake LC, Zabetakis D, Sugiharto VA, Chen HW, Lee CR, Defang GN, Wu SJL, Venkateswaran N, Goldman ER. Oriented Immobilization of Single-Domain Antibodies Using SpyTag/SpyCatcher Yields Improved Limits of Detection. Anal Chem 2019; 91:9424-9429. [DOI: 10.1021/acs.analchem.9b02096] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- George P. Anderson
- Center for Biomolecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
| | - Jinny L. Liu
- Center for Biomolecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
| | - Lisa C. Shriver-Lake
- Center for Biomolecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
| | - Dan Zabetakis
- Center for Biomolecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
| | - Victor A. Sugiharto
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, Maryland 20910, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Bethesda, Maryland 20817, United States
| | - Hua-Wei Chen
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, Maryland 20910, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Bethesda, Maryland 20817, United States
| | - Cheng-Rei Lee
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, Maryland 20910, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Bethesda, Maryland 20817, United States
| | - Gabriel N. Defang
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, Maryland 20910, United States
| | - Shuenn-Jue L. Wu
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, Maryland 20910, United States
| | - Neeraja Venkateswaran
- Tetracore, Inc., 9901 Belward Campus Drive, Suite 300, Rockville, Maryland 20850, United States
| | - Ellen R. Goldman
- Center for Biomolecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
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7
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Walker JA, Robinson KJ, Munro C, Gengenbach T, Muller DA, Young PR, Lua LHL, Corrie SR. Antibody-Binding, Antifouling Surface Coatings Based on Recombinant Expression of Zwitterionic EK Peptides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:1266-1272. [PMID: 29801414 DOI: 10.1021/acs.langmuir.8b00810] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Development of antifouling films which selectively capture or target proteins of interest is essential for controlling interactions at the "bio/nano" interface. However, in order to synthesize biofunctional films from synthetic polymers that incorporate chemical "motifs" for surface immobilization, antifouling, and oriented biomolecule attachment, multiple reaction steps need to be carried out at the solid/liquid interface. EKx is a zwitterionic peptide that has previously been shown to have excellent antifouling properties. In this study, we recombinantly expressed EKx peptides and genetically encoded both surface attachment and antibody-binding motifs, before characterizing the resultant biopolymers by traditional methods. These peptides were then immobilized to organosilica nanoparticles for binding IgG, and subsequently capturing dengue NS1 as a model antigen from serum-containing solution. We found that a mixed layer of a short peptide (4.9 kDa) "backfilled" with a longer peptide terminated with an IgG-binding Z-domain (18 kDa) demonstrated selective capture of dengue NS1 protein down to ∼10 ng mL-1 in either PBS or 20% serum.
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Affiliation(s)
- Julia A Walker
- Department of Chemical Engineering , Monash University , Clayton , Victoria , 3800 , Australia
- ARC Centre of Excellence in Convergent BioNano Science and Technology, Monash Node , Monash University , Clayton , Victoria 3800 , Australia
| | - Kye J Robinson
- Department of Chemical Engineering , Monash University , Clayton , Victoria , 3800 , Australia
- ARC Centre of Excellence in Convergent BioNano Science and Technology, Monash Node , Monash University , Clayton , Victoria 3800 , Australia
| | - Christopher Munro
- The University of Queensland, Protein Expression Facility , Brisbane , Queensland 4072 , Australia
| | | | - David A Muller
- School of Chemistry and Molecular Biosciences , The University of Queensland , Brisbane , Queensland 4072 , Australia
| | - Paul R Young
- School of Chemistry and Molecular Biosciences , The University of Queensland , Brisbane , Queensland 4072 , Australia
| | - Linda H L Lua
- The University of Queensland, Protein Expression Facility , Brisbane , Queensland 4072 , Australia
| | - Simon R Corrie
- Department of Chemical Engineering , Monash University , Clayton , Victoria , 3800 , Australia
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8
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Campuzano S, Pedrero M, Yáñez-Sedeño P, Pingarrón JM. Antifouling (Bio)materials for Electrochemical (Bio)sensing. Int J Mol Sci 2019; 20:E423. [PMID: 30669466 PMCID: PMC6358752 DOI: 10.3390/ijms20020423] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/13/2019] [Accepted: 01/16/2019] [Indexed: 12/20/2022] Open
Abstract
(Bio)fouling processes arising from nonspecific adsorption of biological materials (mainly proteins but also cells and oligonucleotides), reaction products of neurotransmitters oxidation, and precipitation/polymerization of phenolic compounds, have detrimental effects on reliable electrochemical (bio)sensing of relevant analytes and markers either directly or after prolonged incubation in rich-proteins samples or at extreme pH values. Therefore, the design of antifouling (bio)sensing interfaces capable to minimize these undesired processes is a substantial outstanding challenge in electrochemical biosensing. For this purpose, efficient antifouling strategies involving the use of carbon materials, metallic nanoparticles, catalytic redox couples, nanoporous electrodes, electrochemical activation, and (bio)materials have been proposed so far. In this article, biomaterial-based strategies involving polymers, hydrogels, peptides, and thiolated self-assembled monolayers are reviewed and critically discussed. The reported strategies have been shown to be successful to overcome (bio)fouling in a diverse range of relevant practical applications. We highlight recent examples for the reliable sensing of particularly fouling analytes and direct/continuous operation in complex biofluids or harsh environments. Opportunities, unmet challenges, and future prospects in this field are also pointed out.
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Affiliation(s)
- Susana Campuzano
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - María Pedrero
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - Paloma Yáñez-Sedeño
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - José M Pingarrón
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
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9
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Liu JL, Shriver-Lake LC, Zabetakis D, Goldman ER, Anderson GP. Selection of Single-Domain Antibodies towards Western Equine Encephalitis Virus. Antibodies (Basel) 2018; 7:E44. [PMID: 31544894 PMCID: PMC6698954 DOI: 10.3390/antib7040044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 12/12/2018] [Accepted: 12/12/2018] [Indexed: 12/21/2022] Open
Abstract
In this work, we describe the selection and characterization of single-domain antibodies (sdAb) towards the E2/E3E2 envelope protein of the Western equine encephalitis virus (WEEV). Our purpose was to identify novel recognition elements which could be used for the detection, diagnosis, and perhaps treatment of western equine encephalitis (WEE). To achieve this goal, we prepared an immune phage display library derived from the peripheral blood lymphocytes of a llama that had been immunized with an equine vaccine that includes killed WEEV (West Nile Innovator + VEWT). This library was panned against recombinant envelope (E2/E3E2) protein from WEEV, and seven representative sdAb from the five identified sequence families were characterized. The specificity, affinity, and melting point of each sdAb was determined, and their ability to detect the recombinant protein in a MagPlex sandwich immunoassay was confirmed. Thus, these new binders represent novel recognition elements for the E2/E3E2 proteins of WEEV that are available to the research community for further investigation into their applicability for use in the diagnosis or treatment of WEE.
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Affiliation(s)
- Jinny L Liu
- Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC 20375, USA.
| | - Lisa C Shriver-Lake
- Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC 20375, USA.
| | - Dan Zabetakis
- Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC 20375, USA.
| | - Ellen R Goldman
- Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC 20375, USA.
| | - George P Anderson
- Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC 20375, USA.
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10
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Golden J, Yates MD, Halsted M, Tender L. Application of electrochemical surface plasmon resonance (ESPR) to the study of electroactive microbial biofilms. Phys Chem Chem Phys 2018; 20:25648-25656. [PMID: 30289415 DOI: 10.1039/c8cp03898h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Electrochemical surface plasmon resonance (ESPR) monitors faradaic processes optically by the change in refractive index that occurs with a change in redox state at the electrode surface. Here we apply ESPR to investigate the anode-grown Geobacter sulfurreducens biofilm (GSB), a model system used to study electroactive microbial biofilms (EABFs) which perform electrochemical reactions using electrodes as metabolic electron acceptors or donors. A substantial body of evidence indicates that electron transfer reactions among hemes of c-type cytochromes (c-Cyt) play major roles in the extracellular electron transfer (EET) pathways that connect intracellular metabolic processes of cells in an EABF to the electrode surface. The results reported here reveal that when the potential of the electrode is changed from relatively oxidizing (0.40 V vs. SHE) to reducing (-0.55 V vs. SHE) and then back to oxidizing, 70% of c-Cyt residing closest to the biofilm/electrode (within hundreds of nm from the electrode surface) appear to remain trapped in the reduced state, requiring as long as 12 hours to be re-oxidized. c-Cyt storing electrons cannot contribute to EET, yet turnover current resulting from cellular oxidation of acetate coupled with EET to the electrode surface is unaffected. This suggests that a relatively small fraction of c-Cyt residing closest to the biofilm/electrode interface is involved in EET while the majority store electrons. The results also reveal that biomass density at the biofilm/electrode interface increases rapidly during lag phase, reaching its maximum value at the onset of exponential biofilm growth when turnover current begins to rapidly increase.
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Affiliation(s)
- Joel Golden
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington DC, 20375, USA.
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11
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12
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Goldman ER, Liu JL, Zabetakis D, Anderson GP. Enhancing Stability of Camelid and Shark Single Domain Antibodies: An Overview. Front Immunol 2017; 8:865. [PMID: 28791022 PMCID: PMC5524736 DOI: 10.3389/fimmu.2017.00865] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Accepted: 07/07/2017] [Indexed: 11/13/2022] Open
Abstract
Single domain antibodies (sdAbs) are gaining a reputation as superior recognition elements as they combine the advantages of the specificity and affinity found in conventional antibodies with high stability and solubility. Melting temperatures (Tms) of sdAbs cover a wide range from below 50 to over 80°C. Many sdAbs have been engineered to increase their Tm, making them stable until exposed to extreme temperatures. SdAbs derived from the variable heavy chains of camelid and shark heavy chain-only antibodies are termed VHH and VNAR, respectively, and generally exhibit some ability to refold and bind antigen after heat denaturation. This ability to refold varies from 0 to 100% and is a property dependent on both intrinsic factors of the sdAb and extrinsic conditions such as the sample buffer ionic strength, pH, and sdAb concentration. SdAbs have also been engineered to increase their solubility and refolding ability, which enable them to function even after exposure to temperatures that exceed their melting point. In addition, efforts to improve their stability at extreme pH and in the presence of chemical denaturants or proteases have been undertaken. Multiple routes have been employed to engineer sdAbs with these enhanced stabilities. The methods utilized to achieve these goals include grafting complementarity-determining regions onto stable frameworks, introduction of non-canonical disulfide bonds, random mutagenesis combined with stringent selection, point mutations such as inclusion of negative charges, and genetic fusions. Increases of up to 20°C have been realized, pushing the Tm of some sdAbs to over 90°C. Herein, we present an overview of the work done to stabilize sdAbs derived from camelids and sharks. Utilizing these various strategies sdAbs have been stabilized without significantly compromising their affinity, thereby providing superior reagents for detection, diagnostic, and therapeutic applications.
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Affiliation(s)
- Ellen R Goldman
- Center for BioMolecular Science and Engineering, US Naval Research Laboratory, Washington, DC, United States
| | - Jinny L Liu
- Center for BioMolecular Science and Engineering, US Naval Research Laboratory, Washington, DC, United States
| | - Dan Zabetakis
- Center for BioMolecular Science and Engineering, US Naval Research Laboratory, Washington, DC, United States
| | - George P Anderson
- Center for BioMolecular Science and Engineering, US Naval Research Laboratory, Washington, DC, United States
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13
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Pairing Alpaca and Llama-Derived Single Domain Antibodies to Enhance Immunoassays for Ricin. Antibodies (Basel) 2017; 6:antib6010003. [PMID: 31548519 PMCID: PMC6698814 DOI: 10.3390/antib6010003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/17/2017] [Indexed: 11/16/2022] Open
Abstract
Previously, our group isolated and evaluated anti-ricin single domain antibodies (sdAbs) derived from llamas, engineered them to further increase their thermal stability, and utilized them for the development of sensitive immunoassays. In work focused on the development of therapeutics, Vance et al. 2013 described anti-ricin sdAbs derived from alpacas. Herein, we evaluated the utility of selected alpaca-derived anti-ricin sdAbs for detection applications, and engineered an alpaca-derived sdAb to increase its melting temperature, providing a highly thermal stable reagent for use in ricin detection. Four of the alpaca-derived anti-ricin A-chain sdAbs were produced and characterized. All four bound to epitopes that overlapped with our previously described llama sdAbs. One alpaca sdAb, F6, was found to possess both a high melting temperature (73 °C) and to work optimally with a thermally stable llama anti-ricin sdAb in sandwich assays for ricin detection. We employed a combination of consensus sequence mutagenesis and the addition of a non-canonical disulfide bond to further enhance the thermal stability of F6 to 85 °C. It is advantageous to have a choice of recognition reagents when developing assays. This work resulted in defining an additional pair of highly thermal stable sdAbs for the sensitive detection of ricin.
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14
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Liu JL, Zabetakis D, Goldman ER, Anderson GP. Selection and characterization of single domain antibodies against human CD20. Mol Immunol 2016; 78:146-154. [DOI: 10.1016/j.molimm.2016.09.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 09/07/2016] [Accepted: 09/10/2016] [Indexed: 01/25/2023]
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15
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Vashist SK, Schneider EM, Barth E, Luong JH. Surface plasmon resonance-based immunoassay for procalcitonin. Anal Chim Acta 2016; 938:129-36. [DOI: 10.1016/j.aca.2016.08.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 08/02/2016] [Accepted: 08/04/2016] [Indexed: 01/23/2023]
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16
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Mauriz E, García-Fernández M, Lechuga L. Towards the design of universal immunosurfaces for SPR-based assays: A review. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2016.02.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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Ikonomova SP, He Z, Karlsson AJ. A simple and robust approach to immobilization of antibody fragments. J Immunol Methods 2016; 435:7-16. [PMID: 27142477 DOI: 10.1016/j.jim.2016.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 04/06/2016] [Accepted: 04/29/2016] [Indexed: 11/18/2022]
Abstract
Antibody fragments, such as the single-chain variable fragment (scFv), have much potential in research and diagnostics because of their antigen-binding ability similar to a full-sized antibody and their ease of production in microorganisms. Some applications of antibody fragments require immobilization on a surface, and we have established a simple immobilization method that is based on the biotin-streptavidin interaction and does not require a separate purification step. We genetically fused two biotinylation tags-the biotin carboxyl carrier protein (BCCP) or the AviTag minimal sequence-to six different scFvs (scFv13R4, scFvD10, scFv26-10, scFv3, scFv5, and scFv12) for site-specific biotinylation in vivo by endogenous biotin ligases produced by Escherichia coli. The biotinylated scFvs were immobilized onto streptavidin-coated plates directly from cell lysates, and immobilization was detected through enzyme-linked immunosorbent assays. All scFvs fusions were successfully immobilized, and scFvs biotinylated via the BCCP tag tended to immobilize better than those biotinylated via the AviTag, even when biotinylation efficiency was improved with the biotin ligase BirA. The ability of immobilized scFvs to bind antigens was confirmed using scFv13R4 and scFvD10 with their respective targets β-galactosidase and bacteriophage lambda head protein D (gpD). The immobilized scFv13R4 bound to β-galactosidase at the same level for both biotinylation tags when the surface was saturated with the scFv, and immobilized scFvs retained their functionality for at least 100days after immobilization. The simplicity and robustness of our method make it a promising approach for future applications that require antibody fragment immobilization.
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Affiliation(s)
- Svetlana P Ikonomova
- Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Building (#090), College Park, MD 20742, USA
| | - Ziming He
- Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Building (#090), College Park, MD 20742, USA
| | - Amy J Karlsson
- Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Building (#090), College Park, MD 20742, USA.
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18
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Liu JL, Walper SA, Turner KB, Lee AB, Medintz IL, Susumu K, Oh E, Zabetakis D, Goldman ER, Anderson GP. Conjugation of biotin-coated luminescent quantum dots with single domain antibody-rhizavidin fusions. ACTA ACUST UNITED AC 2016; 10:56-65. [PMID: 28352525 PMCID: PMC5040863 DOI: 10.1016/j.btre.2016.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/28/2022]
Abstract
Single domain antibody—rhizavidin fusion bioconjugated biotin coated quantum dots. Provided facile and effective method to orient antibodies on QD surface. Accomplished improved production of His-tagged rhizavidin (RZh) in E. coli. Demonstrated utility of RZh as a replacement for tetrameric biotin binders.
Straightforward and effective methods are required for the bioconjugation of proteins to surfaces and particles. Previously we demonstrated that the fusion of a single domain antibody with the biotin binding molecule rhizavidin provided a facile method to coat biotin-modified surfaces with a highly active and oriented antibody. Here, we constructed similar single domain antibody—rhizavidin fusions as well as unfused rhizavidin with a His-tag. The unfused rhizavidin produced efficiently and its utility for assay development was demonstrated in surface plasmon resonance experiments. The single domain antibody-rhizavidin fusions were utilized to coat quantum dots that had been prepared with surface biotins. Preparation of antibody coated quantum dots by this means was found to be both easy and effective. The prepared single domain antibody-quantum dot reagent was characterized by surface plasmon resonance and applied to toxin detection in a fluoroimmunoassay sensing format.
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Affiliation(s)
- Jinny L Liu
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
| | - Scott A Walper
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
| | - Kendrick B Turner
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
| | | | - Igor L Medintz
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
| | - Kimihiro Susumu
- Sotera Defense Solutions, Inc., 7230 Lee Deforest Drive, Columbia, MD 21046, USA
| | - Eunkeu Oh
- Sotera Defense Solutions, Inc., 7230 Lee Deforest Drive, Columbia, MD 21046, USA
| | - Dan Zabetakis
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
| | - Ellen R Goldman
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
| | - George P Anderson
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave SW, Washington DC 20375, USA
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19
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Turner KB, Alves NJ, Medintz IL, Walper SA. Improving the targeting of therapeutics with single-domain antibodies. Expert Opin Drug Deliv 2016; 13:561-70. [DOI: 10.1517/17425247.2016.1133583] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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20
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Bosmans RPG, Hendriksen WE, Verheijden M, Eelkema R, Jonkheijm P, van Esch JH, Brunsveld L. Supramolecular Protein Immobilization on Lipid Bilayers. Chemistry 2015; 21:18466-73. [DOI: 10.1002/chem.201502461] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Indexed: 01/08/2023]
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21
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Vashist SK, Schneider EM, Luong JHT. Surface plasmon resonance-based immunoassay for human fetuin A. Analyst 2015; 139:2237-42. [PMID: 24652275 DOI: 10.1039/c4an00149d] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article describes a highly-sensitive surface plasmon resonance (SPR)-based immunoassay (IA) for human fetuin A (HFA), a specific biomarker for atherosclerosis and hepatocellular carcinoma. The assay is based on a novel immobilization procedure that simply involves the dilution of an anti-HFA capture antibody (Ab) in 1% (v/v) 3-aminopropyltriethoxysilane (APTES), followed by its dispensing on a KOH-treated gold (Au)-coated SPR chip and incubation for 30 min. The developed SPR IA detected 0.3-20 ng mL(-1) of HFA with a limit of detection and sensitivity of 0.7 ng mL(-1) and 1 ng mL(-1), respectively. The highly-simplified Ab immobilization procedure is also 5-fold more rapid than conventional procedures. It leads to the leach-proof binding of the capture Ab, which means that the developed SPR IA is highly cost-effective, as the Ab-bound SPR chip could be reused for many repeated HFA IAs after regeneration with 10 mM glycine-HCl, pH 2.0. The Ab-bound SPR chip, stored at 4 °C, lost only 18% of its original activity after 4 months. For the detection of HFA spiked in diluted human whole blood and plasma, the results obtained by the developed SPR IA agreed well with the commercial HFA sandwich ELISA.
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Affiliation(s)
- S K Vashist
- HSG-IMIT - Institut für Mikro - und Informationstechnik, Georges-Koehler Allee 103, 79110 Freiburg, Germany.
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22
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Raphael MP, Christodoulides JA, Byers JM, Anderson GP, Liu JL, Turner KB, Goldman ER, Delehanty JB. Optimizing Nanoplasmonic Biosensor Sensitivity with Orientated Single Domain Antibodies. PLASMONICS (NORWELL, MASS.) 2015; 10:1649-1655. [PMID: 26594135 PMCID: PMC4644190 DOI: 10.1007/s11468-015-9969-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 05/08/2015] [Indexed: 06/05/2023]
Abstract
Localized surface plasmon resonance (LSPR) spectroscopy and imaging are emerging biosensor technologies which tout label-free biomolecule detection at the nanoscale and ease of integration with standard microscopy setups. The applicability of these techniques can be limited by the restrictions that surface-conjugated ligands must be both sufficiently small and orientated to meet analyte sensitivity requirements. We demonstrate that orientated single domain antibodies (sdAb) can optimize nanoplasmonic sensitivity by comparing three anti-ricin sdAb constructs to biotin-neutravidin, a model system for small and highly orientated ligand studies. LSPR imaging of electrostatically orientated sdAb exhibited a ricin sensitivity equivalent to that of the biotinylated LSPR biosensors for neutravidin. These results, combined with the facts that sdAb are highly stable and readily produced in bacteria and yeast, build a compelling case for the increased utilization of sdAbs in nanoplasmonic applications.
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Affiliation(s)
- Marc P. Raphael
- />Bioelectronics and Sensing, Code 6363, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - Joseph A. Christodoulides
- />Bioelectronics and Sensing, Code 6363, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - Jeff M. Byers
- />Bioelectronics and Sensing, Code 6363, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - George P. Anderson
- />Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - Jinny L. Liu
- />Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - Kendrick B. Turner
- />Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - Ellen R. Goldman
- />Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
| | - James B. Delehanty
- />Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 USA
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23
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Vashist SK, Schneider EM, Luong JHT. Surface plasmon resonance-based immunoassay for human C-reactive protein. Analyst 2015; 140:4445-52. [DOI: 10.1039/c5an00690b] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A rapid and highly-sensitive surface plasmon resonance (SPR)-based immunoassay (IA) has been developed and validated for detecting human C-reactive protein (CRP), a specific biomarker for inflammatory and metabolic disorders, and infections.
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Affiliation(s)
- S. K. Vashist
- HSG-IMIT – Institut für Mikro- und Informationstechnik
- 79110 Freiburg
- Germany
- Laboratory for MEMS Applications
- Department of Microsystems Engineering – IMTEK
| | - E. M. Schneider
- Sektion Experimentelle Anaesthesiologie
- University Hospital Ulm
- 89081 Ulm
- Germany
| | - J. H. T. Luong
- Innovative Chromatography Group
- Irish Separation Science Cluster (ISSC)
- Department of Chemistry and Analytical
- Biological Chemistry Research Facility (ABCRF)
- University College Cork
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24
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Walper SA, Liu JL, Zabetakis D, Anderson GP, Goldman ER. Development and evaluation of single domain antibodies for vaccinia and the L1 antigen. PLoS One 2014; 9:e106263. [PMID: 25211488 PMCID: PMC4161341 DOI: 10.1371/journal.pone.0106263] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 07/30/2014] [Indexed: 11/25/2022] Open
Abstract
There is ongoing interest to develop high affinity, thermal stable recognition elements to replace conventional antibodies in biothreat detection assays. As part of this effort, single domain antibodies that target vaccinia virus were developed. Two llamas were immunized with killed viral particles followed by boosts with the recombinant membrane protein, L1, to stimulate the immune response for envelope and membrane proteins of the virus. The variable domains of the induced heavy chain antibodies were selected from M13 phage display libraries developed from isolated RNA. Selection via biopanning on the L1 antigen produced single domain antibodies that were specific and had affinities ranging from 4×10−9 M to 7.0×10−10 M, as determined by surface plasmon resonance. Several showed good ability to refold after heat denaturation. These L1-binding single domain antibodies, however, failed to recognize the killed vaccinia antigen. Useful vaccinia binding single domain antibodies were isolated by a second selection using the killed virus as the target. The virus binding single domain antibodies were incorporated in sandwich assays as both capture and tracer using the MAGPIX system yielding limits of detection down to 4×105 pfu/ml, a four-fold improvement over the limit obtained using conventional antibodies. This work demonstrates the development of anti-vaccinia single domain antibodies and their incorporation into sandwich assays for viral detection. It also highlights the properties of high affinity and thermal stability that are hallmarks of single domain antibodies.
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Affiliation(s)
- Scott A. Walper
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, United States of America
| | - Jinny L. Liu
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, United States of America
| | - Daniel Zabetakis
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, United States of America
| | - George P. Anderson
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, United States of America
| | - Ellen R. Goldman
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Washington, DC, United States of America
- * E-mail:
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25
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Liu JL, Zabetakis D, Walper SA, Goldman ER, Anderson GP. Bioconjugates of rhizavidin with single domain antibodies as bifunctional immunoreagents. J Immunol Methods 2014; 411:37-42. [PMID: 24946086 DOI: 10.1016/j.jim.2014.06.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 05/09/2014] [Accepted: 06/04/2014] [Indexed: 11/18/2022]
Abstract
Use of the avidin-biotin binding interaction for immunoassay applications is widespread. One advantageous immunoreagent is the recombinant fusion of an antibody fragment with a biotin binding protein. These genetic fusions alleviate the need to prepare chemical conjugates to achieve molecules that combine target recognition with signal transduction or to facilitate the directional immobilization of the binding element. In order for such a fusion protein to be useful, however, it must be able to be produced in good yield. Unfortunately, recombinant production of avidin or streptavidin as well as bioconjugates derived thereof has been problematic. An alternative biotin binding molecule called rhizavidin has been described, which forms a homodimer instead of a tetramer, but it has not been evaluated in genetic fusions with antibody binding domains. Single domain antibodies, the variable domain derived from camelid heavy chain only antibodies, offer binding domains with high affinity, and solubility that are well expressed in Escherichia coli. In this work, we prepared an anti-ricin single domain antibody - rhizavidin bioconjugate and evaluated it on the basis of its production in E. coli and on its activity in comparison to a streptavidin core bioconjugate and unfused single domain antibody. The single domain antibody-rhizavidin bioconjugate produced much better than its streptavidin core counterparts, yielding an average of 14 mg/L, a 20-fold improvement. When used in assays the rhizavidin conjugate provided the same desirable characteristics as the streptavidin core fusion as both capture and detection reagents. Since rhizavidin and single domain antibodies both display impressive thermal stabilities their fusion provides a route to achieve robust bifunctional immunoreagents.
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Affiliation(s)
- Jinny L Liu
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave. SW, Washington, DC 20375, USA
| | - Dan Zabetakis
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave. SW, Washington, DC 20375, USA
| | - Scott A Walper
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave. SW, Washington, DC 20375, USA
| | - Ellen R Goldman
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave. SW, Washington, DC 20375, USA
| | - George P Anderson
- Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, 4555 Overlook Ave. SW, Washington, DC 20375, USA.
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26
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Kinetic Characterization of a Panel of High-Affinity Monoclonal Antibodies Targeting Ricin and Recombinant Re-Formatting for Biosensor Applications. Antibodies (Basel) 2014. [DOI: 10.3390/antib3020215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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27
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Thermostable single domain antibody–maltose binding protein fusion for Bacillus anthracis spore protein BclA detection. Anal Biochem 2014; 447:64-73. [DOI: 10.1016/j.ab.2013.10.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 09/17/2013] [Accepted: 10/23/2013] [Indexed: 02/07/2023]
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28
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Selection and Characterization of Single Domain Antibodies Specific for Bacillus anthracis Spore Proteins. Antibodies (Basel) 2013. [DOI: 10.3390/antib2010152] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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