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Duan H, Abram TG, Cruz AR, Rooijakkers SHM, Geisbrecht BV. New Insights into the Complement Receptor of the Ig Superfamily Obtained from Structural and Functional Studies on Two Mutants. Immunohorizons 2023; 7:806-818. [PMID: 38032267 PMCID: PMC10696418 DOI: 10.4049/immunohorizons.2300064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 11/03/2023] [Indexed: 12/01/2023] Open
Abstract
The extracellular region of the complement receptor of the Ig superfamily (CRIg) binds to certain C3 cleavage products (C3b, iC3b, C3c) and inhibits the alternative pathway (AP) of complement. In this study, we provide further insight into the CRIg protein and describe two CRIg mutants that lack multiple lysine residues as a means of facilitating chemical modifications of the protein. Structural analyses confirmed preservation of the native CRIg architecture in both mutants. In contrast to earlier reports suggesting that CRIg binds to C3b with an affinity of ∼1 μM, we found that wild-type CRIg binds to C3b and iC3b with affinities <100 nM, but to C3c with an affinity closer to 1 μM. We observed this same trend for both lysine substitution mutants, albeit with an apparent ∼2- to 3-fold loss of affinity when compared with wild-type CRIg. Using flow cytometry, we confirmed binding to C3 fragment-opsonized Staphylococcus aureus cells by each mutant, again with an ∼2- to 3-fold decrease when compared with wild-type. Whereas wild-type CRIg inhibits AP-driven lysis of rabbit erythrocytes with an IC50 of 1.6 μM, we observed an ∼3-fold reduction in inhibition for both mutants. Interestingly, we found that amine-reactive crosslinking of the CRIg mutant containing only a single lysine results in a significant improvement in inhibitory potency across all concentrations examined when compared with the unmodified mutant, but in a manner sensitive to the length of the crosslinker. Collectively, our findings provide new insights into the CRIg protein and suggest an approach for engineering increasingly potent CRIg-based inhibitors of the AP.
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Affiliation(s)
- Huiquan Duan
- Department of Biochemistry and Molecular Biophysics, Kansas State University; Manhattan, KS
| | - Troy G. Abram
- Department of Biochemistry and Molecular Biophysics, Kansas State University; Manhattan, KS
| | - Ana Rita Cruz
- Department of Medical Microbiology and Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Suzan H. M. Rooijakkers
- Department of Medical Microbiology and Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Brian V. Geisbrecht
- Department of Biochemistry and Molecular Biophysics, Kansas State University; Manhattan, KS
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Liu B, Cheng L, Gao H, Zhang J, Dong Y, Gao W, Yuan S, Gong T, Huang W. The biology of VSIG4: Implications for the treatment of immune-mediated inflammatory diseases and cancer. Cancer Lett 2023; 553:215996. [PMID: 36343787 DOI: 10.1016/j.canlet.2022.215996] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/30/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022]
Abstract
V-set and immunoglobulin domain containing 4 (VSIG4), a type I transmembrane receptor exclusively expressed in a subset of tissue-resident macrophages, plays a pivotal role in clearing C3-opsonized pathogens and their byproducts from the circulation. VSIG4 maintains immune homeostasis by suppressing the activation of complement pathways or T cells and inducing regulatory T-cell differentiation, thereby inhibiting the development of immune-mediated inflammatory diseases but enhancing cancer progression. Consequently, VSIG4 exhibits a potential therapeutic effect for immune-mediated inflammatory diseases, but also is regarded as a novel target of immune checkpoint inhibition in cancer therapy. Recently, soluble VSIG4, the extracellular domain of VSIG4, shed from the surface of macrophages, has been found to be a biomarker to define macrophage activation-related diseases. This review mainly summarizes recent new findings of VSIG4 in macrophage phagocytosis and immune homeostasis, and discusses its potential diagnostic and therapeutic usage in infection, inflammation, and cancer.
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Affiliation(s)
- Bei Liu
- Department of Hematology, The Fifth Medical Center of PLA General Hospital, Beijing, 100071, China; PLA 307 Clinical College of Anhui Medical University, Beijing, 100071, China
| | - Li Cheng
- Department of Hematology, The Fifth Medical Center of PLA General Hospital, Beijing, 100071, China
| | - Honghao Gao
- Department of Hematology, The Fifth Medical Center of PLA General Hospital, Beijing, 100071, China
| | - Jiale Zhang
- Department of Thoracic Surgery, The Sixth Medical Center of PLA General Hospital, Fuchenglu 6#, Haidian District, Beijing, 100048, China
| | - Yanxin Dong
- Department of Thoracic Surgery, The Sixth Medical Center of PLA General Hospital, Fuchenglu 6#, Haidian District, Beijing, 100048, China
| | - Wenda Gao
- Antagen Institute for Biomedical Research, Boston, MA, 02021, USA
| | - Shunzong Yuan
- Department of Hematology, The Fifth Medical Center of PLA General Hospital, Beijing, 100071, China; PLA 307 Clinical College of Anhui Medical University, Beijing, 100071, China.
| | - Taiqian Gong
- Department of Thoracic Surgery, The Sixth Medical Center of PLA General Hospital, Fuchenglu 6#, Haidian District, Beijing, 100048, China.
| | - Wenrong Huang
- Department of Hematology, The Fifth Medical Center of PLA General Hospital, Beijing, 100071, China.
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Nelson B, Adams J, Kuglstatter A, Li Z, Harris SF, Liu Y, Bohini S, Ma H, Klumpp K, Gao J, Sidhu SS. Structure-Guided Combinatorial Engineering Facilitates Affinity and Specificity Optimization of Anti-CD81 Antibodies. J Mol Biol 2018; 430:2139-2152. [PMID: 29778602 DOI: 10.1016/j.jmb.2018.05.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/08/2018] [Accepted: 05/10/2018] [Indexed: 12/12/2022]
Abstract
Hepatitis C viral infection is the major cause of chronic hepatitis that affects as many as 71 million people worldwide. Rather than target the rapidly shifting viruses and their numerous serotypes, four independent antibodies were made to target the host antigen CD81 and were shown to block hepatitis C viral entry. The single-chain variable fragment of each antibody was crystallized in complex with the CD81 large extracellular loop in order to guide affinity maturation of two distinct antibodies by phage display. Affinity maturation of antibodies using phage display has proven to be critical to therapeutic antibody development and typically involves modification of the paratope for increased affinity, improved specificity, enhanced stability or a combination of these traits. One antibody was engineered for increased affinity for human CD81 large extracellular loop that equated to increased efficacy, while the second antibody was engineered for cross-reactivity with cynomolgus CD81 to facilitate animal model testing. The use of structures to guide affinity maturation library design demonstrates the utility of combining structural analysis with phage display technologies.
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Affiliation(s)
- Bryce Nelson
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Jarrett Adams
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | | | - Zhijian Li
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | | | - Yang Liu
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA
| | | | - Han Ma
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA
| | - Klaus Klumpp
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA
| | - Junjun Gao
- Hoffmann-La Roche Inc., Palo Alto, 94304, CA, USA.
| | - Sachdev S Sidhu
- Banting and Best Department of Medical Research and Department of Medical Genetics, The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada.
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Na H, Laver JD, Jeon J, Singh F, Ancevicius K, Fan Y, Cao WX, Nie K, Yang Z, Luo H, Wang M, Rissland O, Westwood JT, Kim PM, Smibert CA, Lipshitz HD, Sidhu SS. A high-throughput pipeline for the production of synthetic antibodies for analysis of ribonucleoprotein complexes. RNA (NEW YORK, N.Y.) 2016; 22:636-655. [PMID: 26847261 PMCID: PMC4793217 DOI: 10.1261/rna.055186.115] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/12/2015] [Indexed: 06/05/2023]
Abstract
Post-transcriptional regulation of mRNAs plays an essential role in the control of gene expression. mRNAs are regulated in ribonucleoprotein (RNP) complexes by RNA-binding proteins (RBPs) along with associated protein and noncoding RNA (ncRNA) cofactors. A global understanding of post-transcriptional control in any cell type requires identification of the components of all of its RNP complexes. We have previously shown that these complexes can be purified by immunoprecipitation using anti-RBP synthetic antibodies produced by phage display. To develop the large number of synthetic antibodies required for a global analysis of RNP complex composition, we have established a pipeline that combines (i) a computationally aided strategy for design of antigens located outside of annotated domains, (ii) high-throughput antigen expression and purification in Escherichia coli, and (iii) high-throughput antibody selection and screening. Using this pipeline, we have produced 279 antibodies against 61 different protein components of Drosophila melanogaster RNPs. Together with those produced in our low-throughput efforts, we have a panel of 311 antibodies for 67 RNP complex proteins. Tests of a subset of our antibodies demonstrated that 89% immunoprecipitate their endogenous target from embryo lysate. This panel of antibodies will serve as a resource for global studies of RNP complexes in Drosophila. Furthermore, our high-throughput pipeline permits efficient production of synthetic antibodies against any large set of proteins.
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Affiliation(s)
- Hong Na
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1
| | - John D Laver
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Jouhyun Jeon
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1
| | - Fateh Singh
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1
| | - Kristin Ancevicius
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada L5L 1C6 Department of Cell and Systems Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada L5L 1C6
| | - Yujie Fan
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Wen Xi Cao
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Kun Nie
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1 Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Zhenglin Yang
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Hua Luo
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Miranda Wang
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada M5G 0A4
| | - Olivia Rissland
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada M5G 0A4
| | - J Timothy Westwood
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada L5L 1C6 Department of Cell and Systems Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada L5L 1C6
| | - Philip M Kim
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1 Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Department of Computer Science, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Craig A Smibert
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8 Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Sachdev S Sidhu
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1 Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
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Ma Y, Usuwanthim K, Munawara U, Quach A, Gorgani NN, Abbott CA, Hii CS, Ferrante A. Protein kinase cα regulates the expression of complement receptor Ig in human monocyte-derived macrophages. THE JOURNAL OF IMMUNOLOGY 2015; 194:2855-61. [PMID: 25687755 DOI: 10.4049/jimmunol.1303477] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The complement receptor Ig (CRIg) is selectively expressed by macrophages. This receptor not only promotes the rapid phagocytosis of bacteria by macrophages but also has anti-inflammatory and immunosuppressive functions. Previous findings have suggested that protein kinase C (PKC) may be involved in the regulation of CRIg expression in human macrophages. We have now examined the role of PKCα in CRIg expression in human monocyte-derived macrophages (MDM). Macrophages nucleofected with plasmid containing short hairpin RNA against PKCα showed markedly reduced expression of PKCα, but normal PKCζ expression, by Western blotting analysis, and vice versa. PKCα-deficient MDM showed increased expression of CRIg mRNA and protein (both the long and short form), an increase in phagocytosis of complement-opsonized Candida albicans, and decreased production of TNF-α and IL-6. TNF-α caused a marked decrease in CRIg expression, and addition of anti-TNF mAb to the TNF-α-producing MDMs increased CRIg expression. PKCα-deficient macrophages also showed significantly less bacterial LPS-induced downregulation of CRIg. In contrast, cells deficient in PKCα showed decreased expression of CR type 3 (CR3) and decreased production of TNF-α and IL-6 in response to LPS. MDM developed under conditions that increased expression of CRIg over CR3 showed significantly reduced production of TNF-α in response to opsonized C. albicans. The findings indicate that PKCα promotes the downregulation of CRIg and upregulation of CR3 expression and TNF-α and IL-6 production, a mechanism that may promote inflammation.
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Affiliation(s)
- Yuefang Ma
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Kanchana Usuwanthim
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia; Department of Medical Technology, Faculty of Allied Health Sciences, Naresuan University, Phitsanulok 65000, Thailand
| | - Usma Munawara
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia; School of Biological Science, Flinders University, Bedford Park, South Australia 5042, Australia
| | - Alex Quach
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Nick N Gorgani
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia; Children's Medical Research Institute, University of Sydney, Westmead, New South Wales 2145, Australia
| | - Catherine A Abbott
- School of Biological Science, Flinders University, Bedford Park, South Australia 5042, Australia
| | - Charles S Hii
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Antonio Ferrante
- Department of Immunopathology, SA Pathology, Women's and Children's Hospital, North Adelaide, Adelaide, South Australia 5006, Australia; School of Paediatrics and Reproductive Health, Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia; School of Molecular Biosciences, University of Adelaide, Adelaide, South Australia 5005, Australia; and School of Pharmaceutical and Medical Science, University of South Australia, Adelaide, South Australia 5001, Australia
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Quinlan BD, Gardner MR, Joshi VR, Chiang JJ, Farzan M. Direct expression and validation of phage-selected peptide variants in mammalian cells. J Biol Chem 2013; 288:18803-10. [PMID: 23667257 DOI: 10.1074/jbc.m113.452839] [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] [Indexed: 11/06/2022] Open
Abstract
Phage display is a key technology for the identification and maturation of high affinity peptides, antibodies, and other proteins. However, limitations of bacterial expression restrict the range and sensitivity of assays that can be used to evaluate phage-selected variants. To address this problem, selected genes are typically transferred to mammalian expression vectors, a major rate-limiting step in the iterative improvement of peptides and proteins. Here we describe a system that combines phage display and efficient mammalian expression in a single vector, pDQ1. This system permits immediate expression of phage-selected genes as IgG1-Fc fusions in mammalian cells, facilitating the rapid, sensitive characterization of a large number of library outputs for their biochemical and functional properties. We demonstrate the utility of this system by improving the ability of a CD4-mimetic peptide to bind the HIV-1 envelope glycoprotein and neutralize HIV-1 entry. We further improved the potency of the resulting peptide, CD4mim6, by limiting its ability to induce the CD4-bound conformation of the envelope glycoprotein. Thus, CD4mim6 and its variants can be used to investigate the properties of the HIV-1 envelope glycoprotein, and pDQ1 can accelerate the discovery of new peptides and proteins through phage display.
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Affiliation(s)
- Brian D Quinlan
- Department of Infectious Diseases, The Scripps Research Institute, Jupiter, Florida 33458, USA.
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Ricklin D. Manipulating the mediator: modulation of the alternative complement pathway C3 convertase in health, disease and therapy. Immunobiology 2013; 217:1057-66. [PMID: 22964231 DOI: 10.1016/j.imbio.2012.07.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 07/17/2012] [Accepted: 07/17/2012] [Indexed: 10/27/2022]
Abstract
The complement network is increasingly recognized as an important triage system that is able to differentiate between healthy host cells, microbial intruders, cellular debris and immune complexes, and tailor its actions accordingly. At the center of this triage mechanism is the alternative pathway C3 convertase (C3bBb), a potent enzymatic protein complex capable of rapidly converting the inert yet abundant component C3 into powerful effector fragments (C3a and C3b), thereby amplifying the initial response on unprotected surfaces and inducing a variety of effector functions. A fascinating molecular mechanism of convertase assembly and intrinsic regulation, as well as the interplay with a panel of cell surface-bound and soluble inhibitors are essential for directing complement attack to intruders and protecting healthy host cells. While efficiently keeping immune surveillance and homeostasis on track, the reliance on an intricate cascade of interaction and conversion steps also renders the C3 convertase vulnerable to derail. On the one hand, tissue damage, accumulation of debris, or polymorphisms in complement genes may unfavorably shift the balance between activation and regulation, thereby contributing to a variety of clinical conditions. On the other hand, pathogens developed powerful evasion strategies to avoid complement attack by targeting the convertase. Finally, we increasingly challenge our bodies with foreign materials such as biomaterial implants or drug delivery vehicles that may induce adverse effects that are at least partially caused by complement activation and amplification via the alternative pathway. The involvement of the C3 convertase in a range of pathological conditions put this complex into the spotlight of complement-targeted drug discovery efforts. Fortunately, the physiological regulation and microbial evasion approaches provide a rich source of inspiration for the development of powerful treatment options. This review provides insight into the current knowledge about the molecular mechanisms that drive C3 convertase activity, reveals common and divergent strategies of convertase inhibition employed by host and pathogens, and how this inhibitory arsenal can be tapped for developing therapeutic options to treat complement-related diseases.
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Affiliation(s)
- Daniel Ricklin
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia 19104, USA.
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Interactive proteomics research technologies: recent applications and advances. Curr Opin Biotechnol 2011; 22:50-8. [DOI: 10.1016/j.copbio.2010.09.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 09/01/2010] [Accepted: 09/01/2010] [Indexed: 12/25/2022]
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Pande J, Szewczyk MM, Grover AK. Phage display: concept, innovations, applications and future. Biotechnol Adv 2010; 28:849-58. [PMID: 20659548 DOI: 10.1016/j.biotechadv.2010.07.004] [Citation(s) in RCA: 329] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2010] [Revised: 06/27/2010] [Accepted: 07/08/2010] [Indexed: 12/17/2022]
Abstract
Phage display is the technology that allows expression of exogenous (poly)peptides on the surface of phage particles. The concept is simple in principle: a library of phage particles expressing a wide diversity of peptides is used to select those that bind the desired target. The filamentous phage M13 is the most commonly used vector to create random peptide display libraries. Several methods including recombinant techniques have been developed to increase the diversity of the library. On the other extreme, libraries with various biases can be created for specific purposes. For instance, when the sequence of the peptide that binds the target is known, its affinity and selectivity can be increased by screening libraries created with limited mutagenesis of the peptide. Phage libraries are screened for binding to synthetic or native targets. The initial screening of library by basic biopanning has been extended to column chromatography including negative screening and competition between selected phage clones to identify high affinity ligands with greater target specificity. The rapid isolation of specific ligands by phage display is advantageous in many applications including selection of inhibitors for the active and allosteric sites of the enzymes, receptor agonists and antagonists, and G-protein binding modulatory peptides. Phage display has been used in epitope mapping and analysis of protein-protein interactions. The specific ligands isolated from phage libraries can be used in therapeutic target validation, drug design and vaccine development. Phage display can also be used in conjunction with other methods. The past innovations and those to come promise a bright future for this field.
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Affiliation(s)
- Jyoti Pande
- Department of Medicine, HSC 4N41 McMaster Univ, Hamilton, ON, Canada
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