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Velappan N, Ferrara F, D’Angelo S, Close D, Naranjo L, Bolding MR, Mozden SC, Troup CB, McCullough DK, Gomez A, Kedge M, Bradbury ARM. Direct selection of functional fluorescent-protein antibody fusions by yeast display. PLoS One 2023; 18:e0280930. [PMID: 36827414 PMCID: PMC9956592 DOI: 10.1371/journal.pone.0280930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 01/11/2023] [Indexed: 02/26/2023] Open
Abstract
Antibodies are important reagents for research, diagnostics, and therapeutics. Many examples of chimeric proteins combining the specific target recognition of antibodies with complementing functionalities such as fluorescence, toxicity or enzymatic activity have been described. However, antibodies selected solely on the basis of their binding specificities are not necessarily ideal candidates for the construction of chimeras. Here, we describe a high throughput method based on yeast display to directly select antibodies most suitable for conversion to fluorescent chimera. A library of scFv binders was converted to a fluorescent chimeric form, by cloning thermal green protein into the linker between VH and VL, and directly selecting for both binding and fluorescent functionality. This allowed us to directly identify antibodies functional in the single chain TGP format, that manifest higher protein expression, easier protein purification, and one-step binding assays.
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Affiliation(s)
- Nileena Velappan
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, United States of America
| | | | - Sara D’Angelo
- Specifica Inc., Santa Fe, NM, United States of America
| | - Devin Close
- Arup Laboratories, Salt Lake City, UT, United States of America
| | | | - Madeline R. Bolding
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, United States of America
| | - Sarah C. Mozden
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, United States of America
| | | | - Donna K. McCullough
- Microbiology Department, University of Tennessee, Knoxville, TN, United States of America
| | - Analyssa Gomez
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, United States of America
| | - Marijo Kedge
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM, United States of America
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Ratcliffe NA, Furtado Pacheco JP, Dyson P, Castro HC, Gonzalez MS, Azambuja P, Mello CB. Overview of paratransgenesis as a strategy to control pathogen transmission by insect vectors. Parasit Vectors 2022; 15:112. [PMID: 35361286 PMCID: PMC8969276 DOI: 10.1186/s13071-021-05132-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 12/13/2021] [Indexed: 12/12/2022] Open
Abstract
This article presents an overview of paratransgenesis as a strategy to control pathogen transmission by insect vectors. It first briefly summarises some of the disease-causing pathogens vectored by insects and emphasises the need for innovative control methods to counter the threat of resistance by both the vector insect to pesticides and the pathogens to therapeutic drugs. Subsequently, the state of art of paratransgenesis is described, which is a particularly ingenious method currently under development in many important vector insects that could provide an additional powerful tool for use in integrated pest control programmes. The requirements and recent advances of the paratransgenesis technique are detailed and an overview is given of the microorganisms selected for genetic modification, the effector molecules to be expressed and the environmental spread of the transgenic bacteria into wild insect populations. The results of experimental models of paratransgenesis developed with triatomines, mosquitoes, sandflies and tsetse flies are analysed. Finally, the regulatory and safety rules to be satisfied for the successful environmental release of the genetically engineered organisms produced in paratransgenesis are considered.
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Affiliation(s)
- Norman A. Ratcliffe
- Programa de Pós-Graduação em Ciências e Biotecnologia, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
- Department of Biosciences, Swansea University, Singleton Park, Swansea, UK
| | - João P. Furtado Pacheco
- Programa de Pós-Graduação em Ciências e Biotecnologia, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
- Laboratório de Biologia de Insetos, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
| | - Paul Dyson
- Institute of Life Science, Medical School, Swansea University, Singleton Park, Swansea, UK
| | - Helena Carla Castro
- Programa de Pós-Graduação em Ciências e Biotecnologia, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
| | - Marcelo S. Gonzalez
- Programa de Pós-Graduação em Ciências e Biotecnologia, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
- Laboratório de Biologia de Insetos, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
| | - Patricia Azambuja
- Programa de Pós-Graduação em Ciências e Biotecnologia, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
- Laboratório de Biologia de Insetos, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
| | - Cicero B. Mello
- Programa de Pós-Graduação em Ciências e Biotecnologia, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
- Laboratório de Biologia de Insetos, Instituto de Biologia (EGB), Universidade Federal Fluminense (UFF), Niterói, Brazil
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3
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Ward EM, Kizer ME, Imperiali B. Strategies and Tactics for the Development of Selective Glycan-Binding Proteins. ACS Chem Biol 2021; 16:1795-1813. [PMID: 33497192 PMCID: PMC9200409 DOI: 10.1021/acschembio.0c00880] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The influences of glycans impact all biological processes, disease states, and pathogenic interactions. Glycan-binding proteins (GBPs), such as lectins, are decisive tools for interrogating glycan structure and function because of their ease of use and ability to selectively bind defined carbohydrate epitopes and glycosidic linkages. GBP reagents are prominent tools for basic research, clinical diagnostics, therapeutics, and biotechnological applications. However, the study of glycans is hindered by the lack of specific and selective protein reagents to cover the massive diversity of carbohydrate structures that exist in nature. In addition, existing GBP reagents often suffer from low affinity or broad specificity, complicating data interpretation. There have been numerous efforts to expand the GBP toolkit beyond those identified from natural sources through protein engineering, to improve the properties of existing GBPs or to engineer novel specificities and potential applications. This review details the current scope of proteins that bind carbohydrates and the engineering methods that have been applied to enhance the affinity, selectivity, and specificity of binders.
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Affiliation(s)
- Elizabeth M. Ward
- Department of Biology, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
- Microbiology Graduate Program, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
| | - Megan E. Kizer
- Department of Biology, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
| | - Barbara Imperiali
- Department of Biology, Massachusetts Institute of Technology, 31 Ames St, Cambridge, MA 02142, USA
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
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4
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Velappan N, Micheva-Viteva S, Adikari SH, Waldo GS, Lillo AM, Bradbury ARM. Selection and verification of antibodies against the cytoplasmic domain of M2 of influenza, a transmembrane protein. MAbs 2021; 12:1843754. [PMID: 33206590 PMCID: PMC7678940 DOI: 10.1080/19420862.2020.1843754] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Interactions between the cytoplasmic domains of viral transmembrane proteins and host machinery often determine the outcome of viral infection. The M2 protein of influenza A has been identified as a key player in autophagy-mediated viral replication. Here, we describe the engineering and validation of an antibody specific for the cytoplasmic domain of the M2 protein. Through phage and yeast display selection techniques, we obtained an antibody that recognizes: 1) the M2 cytoplasmic domain purified from bacterial inclusion bodies and refolded, 2) full-length M2 recombinant protein expressed in mammalian cells, and 3) native M2 protein in influenza A infected cells. This antibody can serve as a molecular tool to enhance our knowledge of protein–protein interactions between influenza A virus and the host cell machinery. We anticipate the methods described herein will further the development of antibodies specific to the cytoplasmic domains of transmembrane proteins.
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Affiliation(s)
- Nileena Velappan
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos, NM, USA
| | - Sofiya Micheva-Viteva
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos, NM, USA
| | - Samantha H Adikari
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos, NM, USA
| | - Geoffrey S Waldo
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos, NM, USA
| | - Antonietta M Lillo
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos, NM, USA
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5
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Velappan N, Close D, Hung LW, Naranjo L, Hemez C, DeVore N, McCullough DK, Lillo AM, Waldo GS, Bradbury ARM. Construction, characterization and crystal structure of a fluorescent single-chain Fv chimera. Protein Eng Des Sel 2021; 34:gzaa029. [PMID: 33586761 PMCID: PMC7901706 DOI: 10.1093/protein/gzaa029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 12/21/2020] [Accepted: 12/24/2020] [Indexed: 11/12/2022] Open
Abstract
In vitro display technologies based on phage and yeast have a successful history of selecting single-chain variable fragment (scFv) antibodies against various targets. However, single-chain antibodies are often unstable and poorly expressed in Escherichia coli. Here, we explore the feasibility of converting scFv antibodies to an intrinsically fluorescent format by inserting the monomeric, stable fluorescent protein named thermal green, between the light- and heavy-chain variable regions. Our results show that the scTGP format maintains the affinity and specificity of the antibodies, improves expression levels, allows one-step fluorescent assay for detection of binding and is a suitable reagent for epitope binning. We also report the crystal structure of an scTGP construct that recognizes phosphorylated tyrosine on FcεR1 receptor of the allergy pathway.
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Affiliation(s)
- Nileena Velappan
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
- Microbiology Department, University of Tennessee, Knoxville, TN 37996, USA
| | - Devin Close
- ARUP Laboratories, Institute for Clinical and Experimental Pathology, Salt Lake City, UT 84108, USA
- Microbiology Department, University of Tennessee, Knoxville, TN 37996, USA
| | - Li-Wei Hung
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
- Microbiology Department, University of Tennessee, Knoxville, TN 37996, USA
| | - Leslie Naranjo
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
- Specifica Inc., Santa Fe, NM 87505, USA
| | - Colin Hemez
- Graduate Program in Biophysics, Harvard University, Boston, MA 02115 USA
| | - Natasha DeVore
- Chemistry Department, Missouri State University, Springfield, MO 65897, USA
| | - Donna K McCullough
- Microbiology Department, University of Tennessee, Knoxville, TN 37996, USA
| | - Antonietta M Lillo
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Geoffrey S Waldo
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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6
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Ribosome Display Technology: Applications in Disease Diagnosis and Control. Antibodies (Basel) 2020; 9:antib9030028. [PMID: 32605027 PMCID: PMC7551589 DOI: 10.3390/antib9030028] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/06/2020] [Accepted: 06/08/2020] [Indexed: 12/28/2022] Open
Abstract
Antibody ribosome display remains one of the most successful in vitro selection technologies for antibodies fifteen years after it was developed. The unique possibility of direct generation of whole proteins, particularly single-chain antibody fragments (scFvs), has facilitated the establishment of this technology as one of the foremost antibody production methods. Ribosome display has become a vital tool for efficient and low-cost production of antibodies for diagnostics due to its advantageous ability to screen large libraries and generate binders of high affinity. The remarkable flexibility of this method enables its applicability to various platforms. This review focuses on the applications of ribosome display technology in biomedical and agricultural fields in the generation of recombinant scFvs for disease diagnostics and control.
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GloBody Technology: Detecting Anti-Drug Antibody against VH/VL domains. Sci Rep 2020; 10:1860. [PMID: 32024871 PMCID: PMC7002611 DOI: 10.1038/s41598-020-58041-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/26/2019] [Indexed: 12/23/2022] Open
Abstract
The occurrence of anti-drug antibodies following administration of therapeutic monoclonal antibody to patients is a growing problem that is attracting attention from frontline clinicians. Ideally, an initial indicative point of care test would provide guidance to seek testing approved by the regulatory authorities. Here we describe a platform for the detection of IgG anti-drug antibodies that may provide an initial screen for all therapeutic monoclonal antibodies. Synthetic genes encoding Nanoluciferase polypeptides were inserted between the variable heavy and light domain encoding region of known antibody drugs (alemtuzumab and adalimumab) to generate recombinant single chain GloBodies, which retain the drug antibody paratopes and Nanoluciferase activity. In the presence of anti-drug antibodies, the GloBody is bound by specific IgG in the sample. These complexes are captured on immobilised Protein G and the luciferase activity determined. The amount of light generated being indicative of the anti-drug IgG antibody levels in serum. It should be possible to assemble GloBody reagents for all therapeutic monoclonal antibodies and adapt the capture phase to include additional specific isotypes. The assay has the potential to be developed for use with a drop of blood allowing initial pre-screening in a point of care setting.
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8
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Kunamneni A, Clarke EC, Ye C, Bradfute SB, Durvasula R. Generation and Selection of a Panel of Pan-Filovirus Single-Chain Antibodies using Cell-Free Ribosome Display. Am J Trop Med Hyg 2020; 101:198-206. [PMID: 31074409 PMCID: PMC6609206 DOI: 10.4269/ajtmh.18-0658] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Filoviruses, which include ebolaviruses and marburgvirus, can cause outbreaks of highly lethal hemorrhagic fever. This disease causes significant morbidity and mortality in humans and non-human primates, with human fatality rates reaching 90% during some outbreaks. Currently, there is lack of licensed vaccines or antivirals for these viruses. Since early symptoms of filovirus infection mimic more common diseases, there is a strong unmet public health and biodefense need for broad-spectrum filovirus rapid diagnostics. We have generated a panel of mouse single-chain Fv-antibodies (scFvs) to filovirus glycoproteins (GPs) using cell-free ribosome display and determined their cross-reactivity profiles to all known filovirus species. Two scFvs (4-2 and 22-1) were able to detect all known Ebolavirus and Marburgvirus species. This is the first report on ribosome display scFvs that can detect a broad set of filovirus GPs, which demonstrates the potential for use in diagnostics.
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Affiliation(s)
- Adinarayana Kunamneni
- Department of Medicine, Loyola University Medical Center, Chicago, Illinois.,Department of Internal Medicine, Center for Global Health, University of New Mexico, Albuquerque, New Mexico
| | - Elizabeth C Clarke
- Department of Internal Medicine, Center for Global Health, University of New Mexico, Albuquerque, New Mexico
| | - Chunyan Ye
- Department of Internal Medicine, Center for Global Health, University of New Mexico, Albuquerque, New Mexico
| | - Steven B Bradfute
- Department of Internal Medicine, Center for Global Health, University of New Mexico, Albuquerque, New Mexico
| | - Ravi Durvasula
- Department of Internal Medicine, Center for Global Health, University of New Mexico, Albuquerque, New Mexico.,Department of Medicine, Loyola University Medical Center, Chicago, Illinois
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9
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Jose C, Klein N, Wyss S, Fieck A, Hurwitz I, Durvasula R. Recombinant Arthrobacter β-1, 3-glucanase as a potential effector molecule for paratransgenic control of Chagas disease. Parasit Vectors 2013; 6:65. [PMID: 23497594 PMCID: PMC3606369 DOI: 10.1186/1756-3305-6-65] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 03/06/2013] [Indexed: 11/30/2022] Open
Abstract
Background Chagas disease is most often transmitted to humans by Trypanosoma cruzi infected triatomine bugs, and remains a significant cause of morbidity and mortality in Central and South America. Control of Chagas disease has relied mainly on vector eradication. However, development of insect resistance has prompted us to develop a paratransgenic strategy to control vectorial transmission of T. cruzi. Here, the potential role of recombinant endoglucanases as anti-trypanosomal agents for paratransgenic application is examined. The surface of T. cruzi is covered by a thick coat of mucin-like glycoproteins that have been proposed to play a role in the binding of T. cruzi to the membrane surface of the vector gut. We hypothesize that disruption of these glycoconjugates could arrest parasite development in the vector and abort the transmission cycle. In this work, we examine the effects of recombinant Arthrobacter luteus β-1, 3-glucanase expressed via Rhodococcus rhodnii on T. cruzi Sylvio II strain. Methods and results The coding sequence for β-1, 3-glucanase was cloned in-frame to a heterologous promoter/signal sequence from the Mycobacterium kansasii alpha antigen gene resident in an E. coli/R. rhodnii shuttle vector. The resulting construct was confirmed by sequencing, and electroporated into R. rhodnii. Expression products from positive clones were purified from log phase cultures followed by dialysis into physiological buffers. Lysates and media were quantitated by ELISA against rabbit antibody specific to β-1,3-glucanase. Glucanase-positive samples were applied to live T. cruzi parasites in culture and viability accessed by spectrophotometric and fluorescent microscopic measurements. R. rhodnii-expressed β-1,3-glucanase exhibited toxicity against T. cruzi compared to controls when applied at 5 and 10% of the total culture volume. The decrease in cell viability ranged from a maximum of 50% for the media treatments to 80% for the filtered lysates. Conclusions These results suggest that recombinant β-glucanase could be a powerful addition to the arsenal of effector molecules for paratransgenic control of Chagas disease. In future studies, the ability of β-glucanase to function in combination with other effector molecules will be explored. Dual targeting of T. cruzi should not only slow resistance but also permit synergistic or additive lethal effects on T. cruzi.
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Affiliation(s)
- Christo Jose
- Center for Global Health, Department of Internal Medicine, University of New Mexico and New Mexico VA Health Care System, Albuquerque, New Mexico, USA
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Lombardi A, Gianese G, Arcangeli C, Galeffi P, Sperandei M. Bacterial cytoplasm production of an EGFP-labeled single-chain Fv antibody specific for the HER2 human receptor. J Biomol Struct Dyn 2012; 29:425-39. [PMID: 22066531 DOI: 10.1080/07391102.2011.10507396] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The human epidermal growth factor receptor 2 (HER2) is the main diagnostic marker of breast and ovary cancers. Here, to obtain a rapid and sensitive immunodiagnostic tool a single-chain antibody (scFv800E6) specific for the HER2 was fused to the N-terminus of the enhanced green fluorescent protein (EGFP) by a flexible linker. The soluble production of the novel scFv800E6-EGFP protein in the cytoplasm of Escherichia coli was investigated at different induction temperatures (25, 30 and 37°C); the intrinsic fluorescent properties and the binding activity to HER2 positive tumour cells of the fusion protein were analysed. Western blotting and fluorescence analysis of SDS-PAGE revealed the presence of two scFv800E6-EGFP forms, with different mobility and optical properties, their ratio depending on the induction temperature. The fluorescent form maintained the optical fluorescence properties of EGFP and exhibited a binding activity to the HER2-expressing cells comparable to that of the non-fused scFv800E6. In addition, to provide an insight into the effect of the induction temperature on the molecular structure, the folding of the fusion protein was assessed at atomic level by performing molecular dynamics simulations of the homology-derived model of scFv800E6-EGFP at 300 K and 310 K. The comparison of the data collected at these two temperatures revealed that the higher temperature affects specific structural elements. To improve the production of the soluble and functional scFv800E6-EGFP protein, "in silico" results could be utilised for ad hoc design of the molecular structure.
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Affiliation(s)
- Alessio Lombardi
- Institute of Biology and Agrarian Biotechnology (IBBA), National Research Council, via Bassini 15, 20133 Milan, Italy
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11
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Ribosome display of combinatorial antibody libraries derived from mice immunized with heat-killed Xylella fastidiosa and the selection of MopB-specific single-chain antibodies. Appl Environ Microbiol 2012; 78:2638-47. [PMID: 22327580 DOI: 10.1128/aem.07807-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Pierce's disease is a devastating lethal disease of Vitus vinifera grapevines caused by the bacterium Xylella fastidiosa. There is no cure for Pierce's disease, and control is achieved predominantly by suppressing transmission of the glassy-winged sharpshooter insect vector. We present a simple robust approach for the generation of panels of recombinant single-chain antibodies against the surface-exposed elements of X. fastidiosa that may have potential use in diagnosis and/or disease transmission blocking studies. In vitro combinatorial antibody ribosome display libraries were assembled from immunoglobulin transcripts rescued from the spleens of mice immunized with heat-killed X. fastidiosa. The libraries were used in a single round of selection against an outer membrane protein, MopB, resulting in the isolation of a panel of recombinant antibodies. The potential use of selected anti-MopB antibodies was demonstrated by the successful application of the 4XfMopB3 antibody in an enzyme-linked immunosorbent assay (ELISA), a Western blot assay, and an immunofluorescence assay (IFA). These immortalized in vitro recombinant single-chain antibody libraries generated against heat-killed X. fastidiosa are a resource for the Pierce's disease research community that may be readily accessed for the isolation of antibodies against a plethora of X. fastidiosa surface-exposed antigenic molecules.
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Markiv A, Beatson R, Burchell J, Durvasula RV, Kang AS. Expression of recombinant multi-coloured fluorescent antibodies in gor -/trxB- E. coli cytoplasm. BMC Biotechnol 2011; 11:117. [PMID: 22129156 PMCID: PMC3280946 DOI: 10.1186/1472-6750-11-117] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 11/30/2011] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Antibody-fluorophore conjugates are invaluable reagents used in contemporary molecular cell biology for imaging, cell sorting and tracking intracellular events. However they suffer in some cases from batch to batch variation, partial loss of binding and susceptibility to photo-bleaching. In theory, these issues can all be addressed by using recombinant antibody fused directly to genetically encoded fluorescent reporters. However, single-chain fragment variable domains linked by long flexible linkers are themselves prone to disassociation and aggregation, and in some cases with isoelectric points incompatible with use in physiologically relevant milieu. Here we describe a general approach that permits fully functional intracellular production of a range of coloured fluorescent recombinant antibodies with optimally orientated VH/VL interfaces and isoelectric points compatible for use in physiological solutions at pH 7.4 with a binding site to fluorophore stoichiometry of 1:1. RESULTS Here we report the design, assembly, intracellular bacterial production and purification of a panel of novel antibody fluorescent protein fusion constructs. The insertion of monomeric fluorescent protein derived from either Discosoma or Aequorea in-between the variable regions of anti-p185HER2-ECD antibody 4D5-8 resulted in optimal VH/VL interface interactions to create soluble coloured antibodies each with a single binding site, with isoelectric points of 6.5- 6. The fluorescent antibodies used in cell staining studies with SK-BR-3 cells retained the fluorophore properties and antibody specificity functions, whereas the conventional 4D5-8 single chain antibody with a (Gly4Ser)3 linker precipitated at physiological pH 7.4. CONCLUSIONS This modular monomeric recombinant fluorescent antibody platform may be used to create a range of recombinant coloured antibody molecules for quantitative in situ, in vivo and ex vivo imaging, cell sorting and cell trafficking studies. Assembling the single chain antibody with monomeric fluorescent protein linker facilitates optimal variable domain pairing and alters the isoelectric point of the recombinant 4D5-8 protein conferring solubility at physiological pH 7.4. The efficient intracellular expression of these functional molecules opens up the possibility of developing an alternative approach for tagging intracellular targets with fluorescent proteins for a range of molecular cell biology imaging studies.
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Affiliation(s)
- Anatoliy Markiv
- School of Life Sciences, University of Westminster, 115 New Cavendish St, London, W1W 6UW, UK
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Hurwitz I, Fieck A, Read A, Hillesland H, Klein N, Kang A, Durvasula R. Paratransgenic control of vector borne diseases. Int J Biol Sci 2011; 7:1334-44. [PMID: 22110385 PMCID: PMC3221369 DOI: 10.7150/ijbs.7.1334] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2011] [Indexed: 12/21/2022] Open
Abstract
Conventional methodologies to control vector borne diseases with chemical pesticides are often associated with environmental toxicity, adverse effects on human health and the emergence of insect resistance. In the paratransgenic strategy, symbiotic or commensal microbes of host insects are transformed to express gene products that interfere with pathogen transmission. These genetically altered microbes are re-introduced back to the insect where expression of the engineered molecules decreases the host's ability to transmit the pathogen. We have successfully utilized this strategy to reduce carriage rates of Trypanosoma cruzi, the causative agent of Chagas disease, in the triatomine bug, Rhodnius prolixus, and are currently developing this methodology to control the transmission of Leishmania donovani by the sand fly Phlebotomus argentipes. Several effector molecules, including antimicrobial peptides and highly specific single chain antibodies, are currently being explored for their anti-parasite activities in these two systems. In preparation for eventual field use, we are actively engaged in risk assessment studies addressing the issue of horizontal gene transfer from the modified bacteria to environmental microbes.
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Affiliation(s)
| | | | | | | | | | - Angray Kang
- 1. Institute of Dentistry, Queen Mary, University of London, England
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