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Nur A, Lai JY, Ch'ng ACW, Choong YS, Wan Isa WYH, Lim TS. A review of in vitro stochastic and non-stochastic affinity maturation strategies for phage display derived monoclonal antibodies. Int J Biol Macromol 2024; 277:134217. [PMID: 39069045 DOI: 10.1016/j.ijbiomac.2024.134217] [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: 05/15/2024] [Revised: 07/24/2024] [Accepted: 07/25/2024] [Indexed: 07/30/2024]
Abstract
Monoclonal antibodies identified using display technologies like phage display occasionally suffers from a lack of affinity making it unsuitable for application. This drawback is circumvented with the application of affinity maturation. Affinity maturation is an essential step in the natural evolution of antibodies in the immune system. The evolution of molecular based methods has seen the development of various mutagenesis approaches. This allows for the natural evolutionary process during somatic hypermutation to be replicated in the laboratories for affinity maturation to fine-tune the affinity and selectivity of antibodies. In this review, we will discuss affinity maturation strategies for mAbs generated through phage display systems. The review will highlight various in vitro stochastic and non-stochastic affinity maturation approaches that includes but are not limited to random mutagenesis, site-directed mutagenesis, and gene synthesis.
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Affiliation(s)
- Alia Nur
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Jing Yi Lai
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Angela Chiew Wen Ch'ng
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Yee Siew Choong
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Wan Yus Haniff Wan Isa
- School of Medical Sciences, Department of Medicine, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Theam Soon Lim
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia; Analytical Biochemistry Research Centre, Universiti Sains Malaysia, 11800 Penang, Malaysia.
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Komatsu S, Ohno H, Saito H. Target-dependent RNA polymerase as universal platform for gene expression control in response to intracellular molecules. Nat Commun 2023; 14:7256. [PMID: 37978180 PMCID: PMC10656481 DOI: 10.1038/s41467-023-42802-5] [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: 06/21/2023] [Accepted: 10/23/2023] [Indexed: 11/19/2023] Open
Abstract
Controlling gene expression in response to specific molecules is an essential technique for regulating cellular functions. However, current platforms with transcription and translation regulators have a limited number of detectable molecules to induce gene expression. Here to address these issues, we present a Target-dependent RNA polymerase (TdRNAP) that can induce RNA transcription in response to the intracellular target specifically recognized by single antibody. By substituting the fused antibody, we demonstrate that TdRNAPs respond to a wide variety of molecules, including peptides, proteins, RNA, and small molecules, and produce desired transcripts in human cells. Furthermore, we show that multiple TdRNAPs can construct orthogonal and multilayer genetic circuits. Finally, we apply TdRNAP to achieve cell-specific genome editing that is autonomously triggered by detecting the target gene product. TdRNAP can expand the molecular variety for controlling gene expression and provide the genetic toolbox for bioengineering and future therapeutic applications.
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Affiliation(s)
- Shodai Komatsu
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
- Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Hirohisa Ohno
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hirohide Saito
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
- Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan.
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Tong X, Novak BR, Kavousi S, Moldovan D. Single Nucleotides Moving through Nanoslits Composed of Self-Assembled Monolayers via Equilibrium and Nonequilibrium Molecular Dynamics. J Phys Chem B 2021; 125:1259-1270. [PMID: 33481603 DOI: 10.1021/acs.jpcb.0c07797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nonequilibrium molecular dynamics (MD) simulations were used to study the effect of three chemical surface groups on the separation of DNA mononucleotide velocity (or time-of-flight) distributions as they pass through nanoslits. We used nanoslits functionalize with self-assembled monolayers (SAMs) since they have relatively smooth surfaces. The SAM molecules were terminated with either a methyl, methylformyl, or phenoxy group, and the nucleotides were driven electrophoretically with an electric field intensity of 0.1 V/nm in slits about 3 nm wide. Although these large driving forces are physically difficult to achieve experimentally, the simulations are still of great value as they provide molecular level insight into nucleotide translocation events and allow comparison of different surfaces. Nucleotides adsorbed and desorbed from the slit surface multiple times during the simulations. The required slit length for 99% accuracy in identifying the deoxynucleotide monophosphates (dNMPs), based on the separation of the distributions of time of flight, was used to compare the surfaces with shorter lengths indicating more efficient separation. The lengths were 6.5 μm for phenoxy-terminated SAMs, 270 μm for methylformyl-terminated SAMs, and 2400 μm for methyl-terminated SAMs. Our study showed that a slit with a section with methyl termination and the second section with methylformyl termination lead to a required length of 120 μm, which was significantly lower than for only a methylformyl- or methyl-terminated surface.
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Affiliation(s)
- Xinjie Tong
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Brian R Novak
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Sepideh Kavousi
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Dorel Moldovan
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States.,Center for Computation and Technology, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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Liu H, He Y, Beck J, da Silva Teixeira S, Harrison K, Xu Y, Sisley S. Defining vitamin D receptor expression in the brain using a novel VDR Cre mouse. J Comp Neurol 2021; 529:2362-2375. [PMID: 33368246 DOI: 10.1002/cne.25100] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 12/10/2020] [Accepted: 12/16/2020] [Indexed: 12/15/2022]
Abstract
Vitamin D action has been linked to several diseases regulated by the brain including obesity, diabetes, autism, and Parkinson's. However, the location of the vitamin D receptor (VDR) in the brain is not clear due to conflicting reports. We found that two antibodies previously published as specific in peripheral tissues are not specific in the brain. We thus created a new knockin mouse with cre recombinase expression under the control of the endogenous VDR promoter (VDRCre ). We demonstrated that the cre activity in the VDRCre mouse brain (as reported by a cre-dependent tdTomato expression) is highly overlapping with endogenous VDR mRNAs. These VDR-expressing cells were enriched in multiple brain regions including the cortex, amygdala, caudate putamen, and hypothalamus among others. In the hypothalamus, VDR partially colocalized with vasopressin, oxytocin, estrogen receptor-α, and β-endorphin to various degrees. We further functionally validated our model by demonstrating that the endogenous VDR agonist 1,25-dihydroxyvitamin D activated all tested tdTomato+ neurons in the paraventricular hypothalamus but had no effect on neurons without tdTomato fluorescence. Thus, we have generated a new mouse tool that allows us to visualize VDR-expressing cells and to characterize their functions.
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Affiliation(s)
- Hailan Liu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.,Department of Metabolism and Endocrinology, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Yang He
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Jessie Beck
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Silvania da Silva Teixeira
- Department of Pediatrics, Section of Nutrition, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Keisha Harrison
- Department of Food Science and Technology, Oregon State University, Corvallis, Oregon, USA
| | - Yong Xu
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Stephanie Sisley
- Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
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Bozovičar K, Bratkovič T. Evolving a Peptide: Library Platforms and Diversification Strategies. Int J Mol Sci 2019; 21:E215. [PMID: 31892275 PMCID: PMC6981544 DOI: 10.3390/ijms21010215] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/22/2019] [Accepted: 12/25/2019] [Indexed: 12/22/2022] Open
Abstract
Peptides are widely used in pharmaceutical industry as active pharmaceutical ingredients, versatile tools in drug discovery, and for drug delivery. They find themselves at the crossroads of small molecules and proteins, possessing favorable tissue penetration and the capability to engage into specific and high-affinity interactions with endogenous receptors. One of the commonly employed approaches in peptide discovery and design is to screen combinatorial libraries, comprising a myriad of peptide variants of either chemical or biological origin. In this review, we focus mainly on recombinant peptide libraries, discussing different platforms for their display or expression, and various diversification strategies for library design. We take a look at well-established technologies as well as new developments and future directions.
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Affiliation(s)
| | - Tomaž Bratkovič
- Department of Pharmaceutical Biology, Faculty of Pharmacy, University of Ljubljana, Aškerčeva Cesta 7, SI-1000 Ljubljana, Slovenia;
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Lim CC, Choong YS, Lim TS. Cognizance of Molecular Methods for the Generation of Mutagenic Phage Display Antibody Libraries for Affinity Maturation. Int J Mol Sci 2019; 20:E1861. [PMID: 30991723 PMCID: PMC6515083 DOI: 10.3390/ijms20081861] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/10/2019] [Accepted: 04/12/2019] [Indexed: 12/25/2022] Open
Abstract
Antibodies leverage on their unique architecture to bind with an array of antigens. The strength of interaction has a direct relation to the affinity of the antibodies towards the antigen. In vivo affinity maturation is performed through multiple rounds of somatic hypermutation and selection in the germinal centre. This unique process involves intricate sequence rearrangements at the gene level via molecular mechanisms. The emergence of in vitro display technologies, mainly phage display and recombinant DNA technology, has helped revolutionize the way antibody improvements are being carried out in the laboratory. The adaptation of molecular approaches in vitro to replicate the in vivo processes has allowed for improvements in the way recombinant antibodies are designed and tuned. Combinatorial libraries, consisting of a myriad of possible antibodies, are capable of replicating the diversity of the natural human antibody repertoire. The isolation of target-specific antibodies with specific affinity characteristics can also be accomplished through modification of stringent protocols. Despite the ability to screen and select for high-affinity binders, some 'fine tuning' may be required to enhance antibody binding in terms of its affinity. This review will provide a brief account of phage display technology used for antibody generation followed by a summary of different combinatorial library characteristics. The review will focus on available strategies, which include molecular approaches, next generation sequencing, and in silico approaches used for antibody affinity maturation in both therapeutic and diagnostic applications.
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Affiliation(s)
- Chia Chiu Lim
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia.
| | - Yee Siew Choong
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia.
| | - Theam Soon Lim
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Penang 11800, Malaysia.
- Analytical Biochemistry Research Centre, Universiti Sains Malaysia, Penang 11800, Malaysia.
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Cassette hybridization for vector assembly application in antibody chain shuffling. Biotechniques 2018; 65:269-274. [DOI: 10.2144/btn-2018-0031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Gene assembly methods are an integral part of molecular cloning experiments. The majority of existing vector assembly methods stipulate a need for exonucleases, endonucleases and/or the use of single-stranded DNA as starting materials. Here, we introduced a vector assembly method that employs conventional PCR to amplify stable double-stranded DNA fragments and assembles them into functional vectors specifically for antibody chain shuffling. We successfully formed vectors using cassettes amplified from different templates and assembled an array of single chain fragment variable clones of fixed variable heavy chain, with different variable light chains – a chain shuffling process for antibody maturation. The method provides an easy alternative to the conventional cloning process.
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Taylor AI, Holliger P. Selecting Fully-Modified XNA Aptamers Using Synthetic Genetics. ACTA ACUST UNITED AC 2018; 10:e44. [PMID: 29927117 DOI: 10.1002/cpch.44] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This unit describes the application of "synthetic genetics," i.e., the replication of xeno nucleic acids (XNAs), artificial analogs of DNA and RNA bearing alternative backbone or sugar congeners, to the directed evolution of synthetic oligonucleotide ligands (XNA aptamers) specific for target proteins or nucleic acid motifs, using a cross-chemistry selective exponential enrichment (X-SELEX) approach. Protocols are described for synthesis of diverse-sequence XNA repertoires (typically 1014 molecules) using DNA templates, isolation and panning for functional XNA sequences using targets immobilized on solid phase or gel shift induced by target binding in solution, and XNA reverse transcription to allow cDNA amplification or sequencing. The method may be generally applied to select fully-modified XNA aptamers specific for a wide range of target molecules. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Alexander I Taylor
- Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Philipp Holliger
- Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
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The design of target specific antibodies (scFv) by applying de novo workflow: Case study on BmR1 antigen from Brugia malayi. J Mol Graph Model 2017; 76:543-550. [DOI: 10.1016/j.jmgm.2017.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 06/02/2017] [Accepted: 07/05/2017] [Indexed: 11/24/2022]
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10
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Pan X, Yan J, Patel A, Wysocki VH, Bell CE. Mutant poisoning demonstrates a nonsequential mechanism for digestion of double-stranded DNA by λ exonuclease trimers. Biochemistry 2015; 54:942-51. [PMID: 25531139 DOI: 10.1021/bi501431w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
λ Exonuclease (λexo) is a highly processive 5'-3' exonuclease that binds double-stranded DNA (dsDNA) ends and digests the 5'-strand into mononucleotides. The enzyme forms a toroidal homotrimer with a central tapered channel for tracking along the DNA. During catalysis, dsDNA enters the open end of the channel, and the 5'-strand is digested at one of the three active sites. It is currently not known if λexo uses a sequential mechanism, in which the DNA moves from one active site to the next around the trimer for each round of catalysis or a nonsequential mechanism, in which the DNA locks onto a single active site for multiple rounds. To understand how λexo uses its three active sites, we used a mutant poisoning approach, in which a 6xHis-tagged K131A inactive mutant of λexo was mixed with untagged wild type (WT) to form hybrid trimers. Nickel-spin pull-down analysis confirmed complete subunit exchange after 1 h at 37 °C. Exonuclease assays revealed an approximately linear decrease in activity with increasing fraction of mutant, as expected for a nonsequential mechanism. By fitting the observed rates of digestion to a simple mathematical model, the individual rates of the two hybrid species of trimer were determined. This analysis showed that trimers containing only one or two WT subunits contribute significantly to the observed activity, in further agreement with a nonsequential mechanism. Finally, purification of hybrid trimer mixtures by Ni-spin chromatography, to remove the contribution from fully WT trimers, also resulted in significant levels of activity, again consistent with a nonsequential mechanism.
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Affiliation(s)
- Xinlei Pan
- Ohio State Biochemistry Program, ‡Department of Molecular and Cellular Biochemistry, and §Department of Chemistry and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
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Lim BN, Tye GJ, Choong YS, Ong EBB, Ismail A, Lim TS. Principles and application of antibody libraries for infectious diseases. Biotechnol Lett 2014; 36:2381-92. [PMID: 25214212 DOI: 10.1007/s10529-014-1635-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/11/2014] [Indexed: 02/01/2023]
Abstract
Antibodies have been used efficiently for the treatment and diagnosis of many diseases. Recombinant antibody technology allows the generation of fully human antibodies. Phage display is the gold standard for the production of human antibodies in vitro. To generate monoclonal antibodies by phage display, the generation of antibody libraries is crucial. Antibody libraries are classified according to the source where the antibody gene sequences were obtained. The most useful library for infectious diseases is the immunized library. Immunized libraries would allow better and selective enrichment of antibodies against disease antigens. The antibodies generated from these libraries can be translated for both diagnostic and therapeutic applications. This review focuses on the generation of immunized antibody libraries and the potential applications of the antibodies derived from these libraries.
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Affiliation(s)
- Bee Nar Lim
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800, Minden, Penang, Malaysia,
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12
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Tee KL, Wong TS. Polishing the craft of genetic diversity creation in directed evolution. Biotechnol Adv 2013; 31:1707-21. [PMID: 24012599 DOI: 10.1016/j.biotechadv.2013.08.021] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 08/31/2013] [Accepted: 08/31/2013] [Indexed: 12/25/2022]
Abstract
Genetic diversity creation is a core technology in directed evolution where a high quality mutant library is crucial to its success. Owing to its importance, the technology in genetic diversity creation has seen rapid development over the years and its application has diversified into other fields of scientific research. The advances in molecular cloning and mutagenesis since 2008 were reviewed. Specifically, new cloning techniques were classified based on their principles of complementary overhangs, homologous sequences, overlapping PCR and megaprimers and the advantages, drawbacks and performances of these methods were highlighted. New mutagenesis methods developed for random mutagenesis, focused mutagenesis and DNA recombination were surveyed. The technical requirements of these methods and the mutational spectra were compared and discussed with references to commonly used techniques. The trends of mutant library preparation were summarised. Challenges in genetic diversity creation were discussed with emphases on creating "smart" libraries, controlling the mutagenesis spectrum and specific challenges in each group of mutagenesis methods. An outline of the wider applications of genetic diversity creation includes genome engineering, viral evolution, metagenomics and a study of protein functions. The review ends with an outlook for genetic diversity creation and the prospective developments that can have future impact in this field.
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Affiliation(s)
- Kang Lan Tee
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, England, United Kingdom
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Phage display antibodies for diagnostic applications. Biologicals 2013; 41:209-16. [DOI: 10.1016/j.biologicals.2013.04.001] [Citation(s) in RCA: 218] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 03/29/2013] [Accepted: 04/02/2013] [Indexed: 11/23/2022] Open
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Holland EG, Buhr DL, Acca FE, Alderman D, Bovat K, Busygina V, Kay BK, Weiner MP, Kiss MM. AXM mutagenesis: an efficient means for the production of libraries for directed evolution of proteins. J Immunol Methods 2013; 394:55-61. [PMID: 23680235 DOI: 10.1016/j.jim.2013.05.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 05/02/2013] [Accepted: 05/06/2013] [Indexed: 12/31/2022]
Abstract
Affinity maturation is an important part of the recombinant antibody development process. There are several well-established approaches for generating libraries of mutated antibody genes for affinity maturation, but these approaches are generally too laborious or expensive to allow high-throughput, parallel processing of multiple antibodies. Here, we describe a scalable approach that enables the generation of libraries with greater than 10(8) clones from a single Escherichia coli transformation. In our method, a mutated DNA fragment is produced using PCR conditions that promote nucleotide misincorporation into newly synthesized DNA. In the PCR reaction, one of the primers contains at least three phosphorothioate linkages at its 5' end, and treatment of the PCR product with a 5' to 3' exonuclease is used to preferentially remove the strand synthesized with the non-modified primer, resulting in a single-stranded DNA fragment. This fragment then serves as a megaprimer to prime DNA synthesis on a uracilated, circular, single-stranded template in a Kunkel-like mutagenesis reaction that biases nucleotide base-changes between the megaprimer and uracilated DNA sequence in favor of the in vitro synthesized megaprimer. This method eliminates the inefficient subcloning steps that are normally required for the construction of affinity maturation libraries from randomly mutagenized antibody genes.
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