1
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El Salamouni NS, Cater JH, Spenkelink LM, Yu H. Nanobody engineering: computational modelling and design for biomedical and therapeutic applications. FEBS Open Bio 2024. [PMID: 38898362 DOI: 10.1002/2211-5463.13850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/25/2024] [Accepted: 06/10/2024] [Indexed: 06/21/2024] Open
Abstract
Nanobodies, the smallest functional antibody fragment derived from camelid heavy-chain-only antibodies, have emerged as powerful tools for diverse biomedical applications. In this comprehensive review, we discuss the structural characteristics, functional properties, and computational approaches driving the design and optimisation of synthetic nanobodies. We explore their unique antigen-binding domains, highlighting the critical role of complementarity-determining regions in target recognition and specificity. This review further underscores the advantages of nanobodies over conventional antibodies from a biosynthesis perspective, including their small size, stability, and solubility, which make them ideal candidates for economical antigen capture in diagnostics, therapeutics, and biosensing. We discuss the recent advancements in computational methods for nanobody modelling, epitope prediction, and affinity maturation, shedding light on their intricate antigen-binding mechanisms and conformational dynamics. Finally, we examine a direct example of how computational design strategies were implemented for improving a nanobody-based immunosensor, known as a Quenchbody. Through combining experimental findings and computational insights, this review elucidates the transformative impact of nanobodies in biotechnology and biomedical research, offering a roadmap for future advancements and applications in healthcare and diagnostics.
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Affiliation(s)
- Nehad S El Salamouni
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Australia
| | - Jordan H Cater
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Australia
| | - Lisanne M Spenkelink
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Australia
| | - Haibo Yu
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Australia
- ARC Centre of Excellence in Quantum Biotechnology, University of Wollongong, Australia
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2
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Tandiana R, Barletta GP, Soler MA, Fortuna S, Rocchia W. Computational Mutagenesis of Antibody Fragments: Disentangling Side Chains from ΔΔ G Predictions. J Chem Theory Comput 2024; 20:2630-2642. [PMID: 38445482 DOI: 10.1021/acs.jctc.3c01225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
The development of highly potent antibodies and antibody fragments as binding agents holds significant implications in fields such as biosensing and biotherapeutics. Their binding strength is intricately linked to the arrangement and composition of residues at the binding interface. Computational techniques offer a robust means to predict the three-dimensional structure of these complexes and to assess the affinity changes resulting from mutations. Given the interdependence of structure and affinity prediction, our objective here is to disentangle their roles. We aim to evaluate independently six side-chain reconstruction methods and ten binding affinity estimation techniques. This evaluation was pivotal in predicting affinity alterations due to single mutations, a key step in computational affinity maturation protocols. Our analysis focuses on a data set comprising 27 distinct antibody/hen egg white lysozyme complexes, each with crystal structures and experimentally determined binding affinities. Using six different side-chain reconstruction methods, we transformed each structure into its corresponding mutant via in silico single-point mutations. Subsequently, these structures undergo minimization and molecular dynamics simulation. We therefore estimate ΔΔG values based on the original crystal structure, its energy-minimized form, and the ensuing molecular dynamics trajectories. Our research underscores the critical importance of selecting reliable side-chain reconstruction methods and conducting thorough molecular dynamics simulations to accurately predict the impact of mutations. In summary, our study demonstrates that the integration of conformational sampling and scoring is a potent approach to precisely characterizing mutation processes in single-point mutagenesis protocols and crucial for computational antibody design.
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Affiliation(s)
- Rika Tandiana
- Computational MOdelling of NanosCalE and BioPhysical SysTems─CONCEPT Lab Istituto Italiano di Tecnologia (IIT), Via Melen-83, B Block, 16152 Genoa, Italy
| | - German P Barletta
- Computational MOdelling of NanosCalE and BioPhysical SysTems─CONCEPT Lab Istituto Italiano di Tecnologia (IIT), Via Melen-83, B Block, 16152 Genoa, Italy
- The Abdus Salam International Centre for Theoretical Physics─ICTP, Strada Costiera 11, 34151 Trieste, Italy
| | - Miguel Angel Soler
- Dipartimento di Scienze Matematiche, Informatiche e Fisiche, Universita' di Udine, Via delle Scienze 206, 33100 Udine, Italy
| | - Sara Fortuna
- Computational MOdelling of NanosCalE and BioPhysical SysTems─CONCEPT Lab Istituto Italiano di Tecnologia (IIT), Via Melen-83, B Block, 16152 Genoa, Italy
| | - Walter Rocchia
- Computational MOdelling of NanosCalE and BioPhysical SysTems─CONCEPT Lab Istituto Italiano di Tecnologia (IIT), Via Melen-83, B Block, 16152 Genoa, Italy
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3
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Yu H, Mao G, Pei Z, Cen J, Meng W, Wang Y, Zhang S, Li S, Xu Q, Sun M, Xiao K. In Vitro Affinity Maturation of Nanobodies against Mpox Virus A29 Protein Based on Computer-Aided Design. Molecules 2023; 28:6838. [PMID: 37836685 PMCID: PMC10574621 DOI: 10.3390/molecules28196838] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
Mpox virus (MPXV), the most pathogenic zoonotic orthopoxvirus, caused worldwide concern during the SARS-CoV-2 epidemic. Growing evidence suggests that the MPXV surface protein A29 could be a specific diagnostic marker for immunological detection. In this study, a fully synthetic phage display library was screened, revealing two nanobodies (A1 and H8) that specifically recognize A29. Subsequently, an in vitro affinity maturation strategy based on computer-aided design was proposed by building and docking the A29 and A1 three-dimensional structures. Ligand-receptor binding and molecular dynamics simulations were performed to predict binding modes and key residues. Three mutant antibodies were predicted using the platform, increasing the affinity by approximately 10-fold compared with the parental form. These results will facilitate the application of computers in antibody optimization and reduce the cost of antibody development; moreover, the predicted antibodies provide a reference for establishing an immunological response against MPXV.
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Affiliation(s)
- Haiyang Yu
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Guanchao Mao
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Zhipeng Pei
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Jinfeng Cen
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Wenqi Meng
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Yunqin Wang
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Shanshan Zhang
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Songling Li
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Qingqiang Xu
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Mingxue Sun
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
| | - Kai Xiao
- Lab of Toxicology and Pharmacology, Faculty of Naval Medicine, Naval Medical University, Shanghai 200433, China; (G.M.); (Z.P.); (J.C.); (W.M.); (Y.W.); (S.Z.); (S.L.)
- Marine Biomedical Science and Technology Innovation Platform of Lingang Special Area, Shanghai 201306, China
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4
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Ionescu RE. Ultrasensitive Electrochemical Immunosensors Using Nanobodies as Biocompatible Sniffer Tools of Agricultural Contaminants and Human Disease Biomarkers. MICROMACHINES 2023; 14:1486. [PMID: 37630022 PMCID: PMC10456424 DOI: 10.3390/mi14081486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 07/19/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023]
Abstract
Nanobodies (Nbs) are known as camelid single-domain fragments or variable heavy chain antibodies (VHH) that in vitro recognize the antigens (Ag) similar to full-size antibodies (Abs) and in vivo allow immunoreactions with biomolecule cavities inaccessible to conventional Abs. Currently, Nbs are widely used for clinical treatments due to their remarkably improved performance, ease of production, thermal robustness, superior physical and chemical properties. Interestingly, Nbs are also very promising bioreceptors for future rapid and portable immunoassays, compared to those using unstable full-size antibodies. For all these reasons, Nbs are excellent candidates in ecological risk assessments and advanced medicine, enabling the development of ultrasensitive biosensing platforms. In this review, immobilization strategies of Nbs on conductive supports for enhanced electrochemical immune detection of food contaminants (Fcont) and human biomarkers (Hbio) are discussed. In the case of Fcont, the direct competitive immunoassay detection using coating antigen solid surface is the most commonly used approach for efficient Nbs capture which was characterized with cyclic voltammetry (CV) and differential pulse voltammetry (DPV) when the signal decays for increasing concentrations of free antigen prepared in aqueous solutions. In contrast, for the Hbio investigations on thiolated gold electrodes, increases in amperometric and electrochemical impedance spectroscopy (EIS) signals were recorded, with increases in the antigen concentrations prepared in PBS or spiked real human samples.
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Affiliation(s)
- Rodica Elena Ionescu
- Light, Nanomaterials and Nanotechnology (L2n) Laboratory, CNRS EMR 7004, University of Technology of Troyes, 12 Rue Marie Curie CS 42060, 10004 Troyes, France
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5
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Valdés-Tresanco MS, Valdés-Tresanco ME, Jiménez-Gutiérrez DE, Moreno E. Structural Modeling of Nanobodies: A Benchmark of State-of-the-Art Artificial Intelligence Programs. Molecules 2023; 28:molecules28103991. [PMID: 37241731 DOI: 10.3390/molecules28103991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 05/01/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023] Open
Abstract
The number of applications for nanobodies is steadily expanding, positioning these molecules as fast-growing biologic products in the biotechnology market. Several of their applications require protein engineering, which in turn would greatly benefit from having a reliable structural model of the nanobody of interest. However, as with antibodies, the structural modeling of nanobodies is still a challenge. With the rise of artificial intelligence (AI), several methods have been developed in recent years that attempt to solve the problem of protein modeling. In this study, we have compared the performance in nanobody modeling of several state-of-the-art AI-based programs, either designed for general protein modeling, such as AlphaFold2, OmegaFold, ESMFold, and Yang-Server, or specifically designed for antibody modeling, such as IgFold, and Nanonet. While all these programs performed rather well in constructing the nanobody framework and CDRs 1 and 2, modeling CDR3 still represents a big challenge. Interestingly, tailoring an AI method for antibody modeling does not necessarily translate into better results for nanobodies.
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Affiliation(s)
| | - Mario E Valdés-Tresanco
- Centre for Molecular Simulations and Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | | | - Ernesto Moreno
- Faculty of Basic Sciences, University of Medellin, Medellin 050026, Colombia
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6
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Soler MA, Minovski N, Rocchia W, Fortuna S. Replica-exchange optimization of antibody fragments. Comput Biol Chem 2023; 103:107819. [PMID: 36657284 DOI: 10.1016/j.compbiolchem.2023.107819] [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: 10/10/2022] [Revised: 12/16/2022] [Accepted: 01/13/2023] [Indexed: 01/15/2023]
Abstract
In the framework of the rational design of macromolecules capable of binding to a specific target for biosensing applications, we here further develop an evolutionary protocol designed to optimize the binding affinity of protein binders. In particular we focus on the optimization of the binding portion of small antibody fragments known as nanobodies (or VHH) and choose the hen egg white lysozyme (HEWL) as our target. By implementing a replica exchange scheme for this optimization, we show that an initial hit is not needed and similar solutions can be found by either optimizing an already known anti-HEWL VHH or a randomly selected binder (here a VHH selective towards another macromolecule). While we believe that exhaustive searches of the mutation space are most appropriate when only few key residues have to be optimized, in case a lead binder is not available the proposed evolutionary algorithm should be instead the method of choice.
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Affiliation(s)
- Miguel A Soler
- Italian Institute of Technology (IIT), Via Melen 83, B Block, Genova, Italy; Department of Mathematics, Computer Science and Physics, University of Udine, Via delle Scienze 206, Udine, Italy
| | - Nikola Minovski
- Theory Department, Laboratory for Cheminformatics, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia; Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, Trieste, Italy
| | - Walter Rocchia
- Italian Institute of Technology (IIT), Via Melen 83, B Block, Genova, Italy
| | - Sara Fortuna
- Italian Institute of Technology (IIT), Via Melen 83, B Block, Genova, Italy; Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, Trieste, Italy.
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7
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Ferraz MVF, Neto JCS, Lins RD, Teixeira ES. An artificial neural network model to predict structure-based protein-protein free energy of binding from Rosetta-calculated properties. Phys Chem Chem Phys 2023; 25:7257-7267. [PMID: 36810523 DOI: 10.1039/d2cp05644e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The prediction of the free energy (ΔG) of binding for protein-protein complexes is of general scientific interest as it has a variety of applications in the fields of molecular and chemical biology, materials science, and biotechnology. Despite its centrality in understanding protein association phenomena and protein engineering, the ΔG of binding is a daunting quantity to obtain theoretically. In this work, we devise a novel Artificial Neural Network (ANN) model to predict the ΔG of binding for a given three-dimensional structure of a protein-protein complex with Rosetta-calculated properties. Our model was tested using two data sets, and it presented a root-mean-square error ranging from 1.67 kcal mol-1 to 2.45 kcal mol-1, showing a better performance compared to the available state-of-the-art tools. Validation of the model for a variety of protein-protein complexes is showcased.
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Affiliation(s)
- Matheus V F Ferraz
- Department of Virology, Aggeu Magalhães Institute, Oswaldo Cruz Foundation, FIOCRUZ, Recife, PE, Brazil.,Department of Fundamental Chemistry, Federal University of Pernambuco, UFPE, Recife, PE, Brazil.,Heidelberg Institute for Theoretical Studies, HITS, Heidelberg, Germany
| | - José C S Neto
- Recife Center for Advanced Studies and Systems, CESAR, Recife, PE, Brazil.
| | - Roberto D Lins
- Department of Virology, Aggeu Magalhães Institute, Oswaldo Cruz Foundation, FIOCRUZ, Recife, PE, Brazil.,Department of Fundamental Chemistry, Federal University of Pernambuco, UFPE, Recife, PE, Brazil
| | - Erico S Teixeira
- Recife Center for Advanced Studies and Systems, CESAR, Recife, PE, Brazil.
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8
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General Trends of the Camelidae Antibody V HHs Domain Dynamics. Int J Mol Sci 2023; 24:ijms24054511. [PMID: 36901942 PMCID: PMC10003728 DOI: 10.3390/ijms24054511] [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: 02/09/2023] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 03/03/2023] Open
Abstract
Conformational flexibility plays an essential role in antibodies' functional and structural stability. They facilitate and determine the strength of antigen-antibody interactions. Camelidae express an interesting subtype of single-chain antibody, named Heavy Chain only Antibody. They have only one N-terminal Variable domain (VHH) per chain, composed of Frameworks (FRs) and Complementarity Determining regions (CDRs) like their VH and VL counterparts in IgG. Even when expressed independently, VHH domains display excellent solubility and (thermo)stability, which helps them to retain their impressive interaction capabilities. Sequence and structural features of VHH domains contributing to these abilities have already been studied compared to classical antibodies. To have the broadest view and understand the changes in dynamics of these macromolecules, large-scale molecular dynamics simulations for a large number of non-redundant VHH structures have been performed for the first time. This analysis reveals the most prevalent movements in these domains. It reveals the four main classes of VHHs dynamics. Diverse local changes were observed in CDRs with various intensities. Similarly, different types of constraints were observed in CDRs, while FRs close to CDRs were sometimes primarily impacted. This study sheds light on the changes in flexibility in different regions of VHH that may impact their in silico design.
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9
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Medagli B, Soler MA, De Zorzi R, Fortuna S. Antibody Affinity Maturation Using Computational Methods: From an Initial Hit to Small-Scale Expression of Optimized Binders. Methods Mol Biol 2023; 2552:333-359. [PMID: 36346602 DOI: 10.1007/978-1-0716-2609-2_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Nanobodies (VHHs) are engineered fragments of the camelid single-chain immunoglobulins. The VHH domain contains the highly variable segments responsible for antigen recognition. VHHs can be easily produced as recombinant proteins. Their small size is a good advantage for in silico approaches. Computer methods represent a valuable strategy for the optimization and improvement of their binding affinity. They also allow for epitope selection offering the possibility to design new VHHs for regions of a target protein that are not naturally immunogenic. Here we present an in silico mutagenic protocol developed to improve the binding affinity of nanobodies together with the first step of their in vitro production. The method, already proven successful in improving the low Kd of a nanobody hit obtained by panning, can be employed for the ex novo design of antibody fragments against selected protein target epitopes.
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Affiliation(s)
- Barbara Medagli
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy.
| | - Miguel A Soler
- CONCEPT Lab, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Mathematics, Computer Science and Physics, University of Udine, Udine, Italy
| | - Rita De Zorzi
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy.
- CONCEPT Lab, Istituto Italiano di Tecnologia, Genova, Italy.
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10
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Alsadig A, Abbasgholi-NA B, Vondracek H, Medagli B, Fortuna S, Posocco P, Parisse P, Cabrera H, Casalis L. DNA-Directed Protein Anchoring on Oligo/Alkanethiol-Coated Gold Nanoparticles: A Versatile Platform for Biosensing Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 13:nano13010078. [PMID: 36615988 PMCID: PMC9823620 DOI: 10.3390/nano13010078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/12/2022] [Accepted: 12/22/2022] [Indexed: 05/27/2023]
Abstract
Herein, we report on a smart biosensing platform that exploits gold nanoparticles (AuNPs) functionalized through ssDNA self-assembled monolayers (SAM) and the DNA-directed immobilization (DDI) of DNA-protein conjugates; a novel, high-sensitivity optical characterization technique based on a miniaturized gel electrophoresis chip integrated with online thermal lens spectrometry (MGEC-TLS), for the high-sensitivity detection of antigen binding events. Specifically, we characterized the physicochemical properties of 20 nm AuNPs covered with mixed SAMs of thiolated single-stranded DNA and bio-repellent molecules, referred to as top-terminated oligo-ethylene glycol (TOEG6), demonstrating high colloidal stability, optimal binder surface density, and proper hybridization capacity. Further, to explore the design in the frame of cancer-associated antigen detection, complementary ssDNA fragments conjugated with a nanobody, called C8, were loaded on the particles and employed to detect the presence of the HER2-ECD antigen in liquid. At variance with conventional surface plasmon resonance detection, MGEC-TLS characterization confirmed the capability of the assay to titrate the HER2-ECD antigen down to concentrations of 440 ng/mL. The high versatility of the directed protein-DNA conjugates immobilization through DNA hybridization on plasmonic scaffolds and coupled with the high sensitivity of the MGEC-TLS detection qualifies the proposed assay as a potential, easily operated biosensing strategy for the fast and label-free detection of disease-relevant antigens.
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Affiliation(s)
- Ahmed Alsadig
- Department of Physics, University of Trieste, 34127 Trieste, Italy
- NanoInnovation Lab, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - Behnaz Abbasgholi-NA
- NanoInnovation Lab, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
- Optics Lab, STI Unit, The Abdus Salam International Centre for Theoretical Physics, 34151 Trieste, Italy
| | - Hendrik Vondracek
- NanoInnovation Lab, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - Barbara Medagli
- Department of Medicine, Surgery and Health Sciences at the University of Trieste, 34149 Trieste, Italy
| | - Sara Fortuna
- Italian Institute of Technology (IIT), Via Melen–83, B Block, 16152 Genova, Italy
| | - Paola Posocco
- Department of Engineering and Architecture, University of Trieste, 34127 Trieste, Italy
| | - Pietro Parisse
- NanoInnovation Lab, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
- Institute of Materials (IOM-CNR), Area Science Park, 34149 Trieste, Italy
| | - Humberto Cabrera
- Optics Lab, STI Unit, The Abdus Salam International Centre for Theoretical Physics, 34151 Trieste, Italy
| | - Loredana Casalis
- NanoInnovation Lab, Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
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11
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Ochoa R, Cossio P, Fox T. Protocol for iterative optimization of modified peptides bound to protein targets. J Comput Aided Mol Des 2022; 36:825-835. [PMID: 36258137 PMCID: PMC9640467 DOI: 10.1007/s10822-022-00482-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 10/03/2022] [Indexed: 12/02/2022]
Abstract
Peptides are commonly used as therapeutic agents. However, they suffer from easy degradation and instability. Replacing natural by non-natural amino acids can avoid these problems, and potentially improve the affinity towards the target protein. Here, we present a computational pipeline to optimize peptides based on adding non-natural amino acids while improving their binding affinity. The workflow is an iterative computational evolution algorithm, inspired by the PARCE protocol, that performs single-point mutations on the peptide sequence using modules from the Rosetta framework. The modifications can be guided based on the structural properties or previous knowledge of the biological system. At each mutation step, the affinity to the protein is estimated by sampling the complex conformations and applying a consensus metric using various open protein-ligand scoring functions. The mutations are accepted based on the score differences, allowing for an iterative optimization of the initial peptide. The sampling/scoring scheme was benchmarked with a set of protein-peptide complexes where experimental affinity values have been reported. In addition, a basic application using a known protein-peptide complex is also provided. The structure- and dynamic-based approach allows users to optimize bound peptides, with the option to personalize the code for further applications. The protocol, called mPARCE, is available at: https://github.com/rochoa85/mPARCE/.
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Affiliation(s)
- Rodrigo Ochoa
- Biophysics of Tropical Diseases, Max Planck Tandem Group, University of Antioquia, Medellín, 050010, Colombia. .,Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach/Riss, Germany.
| | - Pilar Cossio
- Biophysics of Tropical Diseases, Max Planck Tandem Group, University of Antioquia, Medellín, 050010, Colombia.,Center for Computational Mathematics, Flatiron Institute, New York, 10010, USA.,Center for Computational Biology, Flatiron Institute, New York, 10010, USA
| | - Thomas Fox
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach/Riss, Germany
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12
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In Silico Maturation of a Nanomolar Antibody against the Human CXCR2. Biomolecules 2022; 12:biom12091285. [PMID: 36139124 PMCID: PMC9496334 DOI: 10.3390/biom12091285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 08/31/2022] [Accepted: 08/31/2022] [Indexed: 11/17/2022] Open
Abstract
The steady increase in computational power in the last 50 years is opening unprecedented opportunities in biology, as computer simulations of biological systems have become more accessible and can reproduce experimental results more accurately. Here, we wanted to test the ability of computer simulations to replace experiments in the limited but practically useful scope of improving the biochemical characteristics of the abN48 antibody, a nanomolar antagonist of the CXC chemokine receptor 2 (CXCR2) that was initially selected from a combinatorial antibody library. Our results showed a good correlation between the computed binding energies of the antibody to the peptide target and the experimental binding affinities. Moreover, we showed that it is possible to design new antibody sequences in silico with a higher affinity to the desired target using a Monte Carlo Metropolis algorithm. The newly designed sequences had an affinity comparable to the best ones obtained using in vitro affinity maturation and could be obtained within a similar timeframe. The methodology proposed here could represent a valid alternative for improving antibodies in cases in which experiments are too expensive or technically tricky and could open an opportunity for designing antibodies for targets that have been elusive so far.
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13
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V HH Structural Modelling Approaches: A Critical Review. Int J Mol Sci 2022; 23:ijms23073721. [PMID: 35409081 PMCID: PMC8998791 DOI: 10.3390/ijms23073721] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/23/2022] [Accepted: 03/23/2022] [Indexed: 12/20/2022] Open
Abstract
VHH, i.e., VH domains of camelid single-chain antibodies, are very promising therapeutic agents due to their significant physicochemical advantages compared to classical mammalian antibodies. The number of experimentally solved VHH structures has significantly improved recently, which is of great help, because it offers the ability to directly work on 3D structures to humanise or improve them. Unfortunately, most VHHs do not have 3D structures. Thus, it is essential to find alternative ways to get structural information. The methods of structure prediction from the primary amino acid sequence appear essential to bypass this limitation. This review presents the most extensive overview of structure prediction methods applied for the 3D modelling of a given VHH sequence (a total of 21). Besides the historical overview, it aims at showing how model software programs have been shaping the structural predictions of VHHs. A brief explanation of each methodology is supplied, and pertinent examples of their usage are provided. Finally, we present a structure prediction case study of a recently solved VHH structure. According to some recent studies and the present analysis, AlphaFold 2 and NanoNet appear to be the best tools to predict a structural model of VHH from its sequence.
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14
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Wang J, Kang G, Yuan H, Cao X, Huang H, de Marco A. Research Progress and Applications of Multivalent, Multispecific and Modified Nanobodies for Disease Treatment. Front Immunol 2022; 12:838082. [PMID: 35116045 PMCID: PMC8804282 DOI: 10.3389/fimmu.2021.838082] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 12/30/2021] [Indexed: 12/22/2022] Open
Abstract
Recombinant antibodies such as nanobodies are progressively demonstrating to be a valid alternative to conventional monoclonal antibodies also for clinical applications. Furthermore, they do not solely represent a substitute for monoclonal antibodies but their unique features allow expanding the applications of biotherapeutics and changes the pattern of disease treatment. Nanobodies possess the double advantage of being small and simple to engineer. This combination has promoted extremely diversified approaches to design nanobody-based constructs suitable for particular applications. Both the format geometry possibilities and the functionalization strategies have been widely explored to provide macromolecules with better efficacy with respect to single nanobodies or their combination. Nanobody multimers and nanobody-derived reagents were developed to image and contrast several cancer diseases and have shown their effectiveness in animal models. Their capacity to block more independent signaling pathways simultaneously is considered a critical advantage to avoid tumor resistance, whereas the mass of these multimeric compounds still remains significantly smaller than that of an IgG, enabling deeper penetration in solid tumors. When applied to CAR-T cell therapy, nanobodies can effectively improve the specificity by targeting multiple epitopes and consequently reduce the side effects. This represents a great potential in treating malignant lymphomas, acute myeloid leukemia, acute lymphoblastic leukemia, multiple myeloma and solid tumors. Apart from cancer treatment, multispecific drugs and imaging reagents built with nanobody blocks have demonstrated their value also for detecting and tackling neurodegenerative, autoimmune, metabolic, and infectious diseases and as antidotes for toxins. In particular, multi-paratopic nanobody-based constructs have been developed recently as drugs for passive immunization against SARS-CoV-2 with the goal of impairing variant survival due to resistance to antibodies targeting single epitopes. Given the enormous research activity in the field, it can be expected that more and more multimeric nanobody molecules will undergo late clinical trials in the next future. Systematic Review Registration.
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Affiliation(s)
- Jiewen Wang
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
- Institute of Shaoxing, Tianjin University, Zhejiang, China
| | - Guangbo Kang
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
- Institute of Shaoxing, Tianjin University, Zhejiang, China
| | - Haibin Yuan
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
- Institute of Shaoxing, Tianjin University, Zhejiang, China
| | - Xiaocang Cao
- Department of Gastroenterology and Hepatology, Tianjin Medical University General Hospital, Tianjin Medical University, Tianjin, China
| | - He Huang
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
- Institute of Shaoxing, Tianjin University, Zhejiang, China
| | - Ario de Marco
- Laboratory for Environmental and Life Sciences, University of Nova Gorica, Nova Gorica, Slovenia
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15
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Ochoa R, Soler MA, Gladich I, Battisti A, Minovski N, Rodriguez A, Fortuna S, Cossio P, Laio A. Computational Evolution Protocol for Peptide Design. Methods Mol Biol 2022; 2405:335-359. [PMID: 35298821 DOI: 10.1007/978-1-0716-1855-4_16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Computational peptide design is useful for therapeutics, diagnostics, and vaccine development. To select the most promising peptide candidates, the key is describing accurately the peptide-target interactions at the molecular level. We here review a computational peptide design protocol whose key feature is the use of all-atom explicit solvent molecular dynamics for describing the different peptide-target complexes explored during the optimization. We describe the milestones behind the development of this protocol, which is now implemented in an open-source code called PARCE. We provide a basic tutorial to run the code for an antibody fragment design example. Finally, we describe three additional applications of the method to design peptides for different targets, illustrating the broad scope of the proposed approach.
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Affiliation(s)
- Rodrigo Ochoa
- Biophysics of Tropical Diseases, Max Planck Tandem Group, University of Antioquia, Medellin, Colombia
| | | | - Ivan Gladich
- Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha, Qatar
- SISSA, Trieste, Italy
| | | | - Nikola Minovski
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
- Theory Department, Laboratory for Cheminformatics, National Institute of Chemistry, Ljubljana, Slovenia
| | - Alex Rodriguez
- The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy
| | - Sara Fortuna
- Italian Institute of Technology (IIT), Genova, Italy
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Pilar Cossio
- Biophysics of Tropical Diseases, Max Planck Tandem Group, University of Antioquia, Medellin, Colombia
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Alessandro Laio
- The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy
- SISSA, Trieste, Italy
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16
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Higashida R, Matsunaga Y. Enhanced Conformational Sampling of Nanobody CDR H3 Loop by Generalized Replica-Exchange with Solute Tempering. Life (Basel) 2021; 11:life11121428. [PMID: 34947959 PMCID: PMC8706460 DOI: 10.3390/life11121428] [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: 09/30/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 12/22/2022] Open
Abstract
The variable domains of heavy-chain antibodies, known as nanobodies, are potential substitutes for IgG antibodies. They have similar affinities to antigens as antibodies, but are more heat resistant. Their small size allows us to exploit computational approaches for structural modeling or design. Here, we investigate the applicability of an enhanced sampling method, a generalized replica-exchange with solute tempering (gREST) for sampling CDR-H3 loop structures of nanobodies. In the conventional replica-exchange methods, temperatures of only a whole system or scaling parameters of a solute molecule are selected for temperature or parameter exchange. In gREST, we can flexibly select a part of a solute molecule and a part of the potential energy terms as a parameter exchange region. We selected the CDR-H3 loop and investigated which potential energy term should be selected for the efficient sampling of the loop structures. We found that the gREST with dihedral terms can explore a global conformational space, but the relaxation to the global equilibrium is slow. On the other hand, gREST with all the potential energy terms can sample the equilibrium distribution, but the structural exploration is slower than with dihedral terms. The lessons learned from this study can be applied to future studies of loop modeling.
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17
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Cantarutti C, Vargas MC, Dongmo Foumthuim CJ, Dumoulin M, La Manna S, Marasco D, Santambrogio C, Grandori R, Scoles G, Soler MA, Corazza A, Fortuna S. Insights on peptide topology in the computational design of protein ligands: the example of lysozyme binding peptides. Phys Chem Chem Phys 2021; 23:23158-23172. [PMID: 34617942 DOI: 10.1039/d1cp02536h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Herein, we compared the ability of linear and cyclic peptides generated in silico to target different protein sites: internal pockets and solvent-exposed sites. We selected human lysozyme (HuL) as a model target protein combined with the computational evolution of linear and cyclic peptides. The sequence evolution of these peptides was based on the PARCE algorithm. The generated peptides were screened based on their aqueous solubility and HuL binding affinity. The latter was evaluated by means of scoring functions and atomistic molecular dynamics (MD) trajectories in water, which allowed prediction of the structural features of the protein-peptide complexes. The computational results demonstrated that cyclic peptides constitute the optimal choice for solvent exposed sites, while both linear and cyclic peptides are capable of targeting the HuL pocket effectively. The most promising binders found in silico were investigated experimentally by surface plasmon resonance (SPR), nuclear magnetic resonance (NMR), and electrospray ionization mass spectrometry (ESI-MS) techniques. All tested peptides displayed dissociation constants in the micromolar range, as assessed by SPR; however, both NMR and ESI-MS suggested multiple binding modes, at least for the pocket binding peptides. A detailed NMR analysis confirmed that both linear and cyclic pocket peptides correctly target the binding site they were designed for.
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Affiliation(s)
- Cristina Cantarutti
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 - Udine, Italy.
| | - M Cristina Vargas
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Unidad Mérida, Apartado Postal 73 "Cordemex", 97310, Mérida, Mexico
| | - Cedrix J Dongmo Foumthuim
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 - Udine, Italy. .,Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Campus Scientifico - Via Torino 155, 30172 Mestre, Italy
| | - Mireille Dumoulin
- Centre for Protein Engineering, InBios, Department of Life Sciences, University of Liege, Liege, Belgium
| | - Sara La Manna
- Department of Pharmacy - University of Naples "Federico II", 80134, Naples, Italy
| | - Daniela Marasco
- Department of Pharmacy - University of Naples "Federico II", 80134, Naples, Italy
| | - Carlo Santambrogio
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza, Milan, Italy
| | - Rita Grandori
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza, Milan, Italy
| | - Giacinto Scoles
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 - Udine, Italy.
| | - Miguel A Soler
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 - Udine, Italy. .,Italian Institute of Technology (IIT), Via Melen - 83, B Block, 16152 - Genova, Italy
| | - Alessandra Corazza
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 - Udine, Italy.
| | - Sara Fortuna
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 - Udine, Italy. .,Italian Institute of Technology (IIT), Via Melen - 83, B Block, 16152 - Genova, Italy.,Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
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18
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Orlando M, Fortuna S, Oloketuyi S, Bajc G, Goldenzweig A, de Marco A. CDR1 Composition Can Affect Nanobody Recombinant Expression Yields. Biomolecules 2021; 11:biom11091362. [PMID: 34572576 PMCID: PMC8465892 DOI: 10.3390/biom11091362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 01/03/2023] Open
Abstract
The isolation of nanobodies from pre-immune libraries by means of biopanning is a straightforward process. Nevertheless, the recovered candidates often require optimization to improve some of their biophysical characteristics. In principle, CDRs are not mutated because they are likely to be part of the antibody paratope, but in this work, we describe a mutagenesis strategy that specifically addresses CDR1. Its sequence was identified as an instability hot spot by the PROSS program, and the available structural information indicated that four CDR1 residues bound directly to the antigen. We therefore modified the loop flexibility with the addition of an extra glycine rather than by mutating single amino acids. This approach significantly increased the nanobody yields but traded-off with moderate affinity loss. Accurate modeling coupled with atomistic molecular dynamics simulations enabled the modifications induced by the glycine insertion and the rationale behind the engineering design to be described in detail.
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Affiliation(s)
- Marco Orlando
- Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100 Varese, Italy;
| | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy;
| | - Sandra Oloketuyi
- Lab of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, Rožna Dolina, 5000 Nova Gorica, Slovenia;
| | - Gregor Bajc
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia;
| | - Adi Goldenzweig
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel;
| | - Ario de Marco
- Lab of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, Rožna Dolina, 5000 Nova Gorica, Slovenia;
- Correspondence: ; Tel.: +386-(05)-3315295
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19
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Fernandes CFC, Pereira SS, Luiz MB, Silva NKRL, Silva MCS, Marinho ACM, Fonseca MHG, Furtado GP, Trevizani R, Nicolete R, Soares AM, Zuliani JP, Stabeli RG. Engineering of single-domain antibodies for next-generation snakebite antivenoms. Int J Biol Macromol 2021; 185:240-250. [PMID: 34118288 DOI: 10.1016/j.ijbiomac.2021.06.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/04/2021] [Accepted: 06/06/2021] [Indexed: 12/29/2022]
Abstract
Given the magnitude of the global snakebite crisis, strategies to ensure the quality of antivenom, as well as the availability and sustainability of its supply are under development by several research groups. Recombinant DNA technology has allowed the engineering of monoclonal antibodies and recombinant fragments as alternatives to conventional antivenoms. Besides having higher therapeutic efficacy, with broad neutralization capacity against local and systemic toxicity, novel antivenoms need to be safe and cost-effective. Due to the biological and physical chemical properties of camelid single-domain antibodies, with high volume of distribution to distal tissue, their modular format, and their versatility, their biotechnological application has grown considerably in recent decades. This article presents the most up-to-date developments concerning camelid single-domain-based antibodies against major toxins from snake venoms, the main venomous animals responsible for reported envenoming cases and related human deaths. A brief discussion on the composition, challenges, and perspectives of antivenoms is presented, as well as the road ahead for next-generation antivenoms based on single-domain antibodies.
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Affiliation(s)
| | - Soraya S Pereira
- Fundação Oswaldo Cruz, Fiocruz Rondônia, and Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Porto Velho, Rondônia, Brazil
| | - Marcos B Luiz
- Fundação Oswaldo Cruz, Fiocruz Rondônia, and Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Porto Velho, Rondônia, Brazil
| | - Nauanny K R L Silva
- Fundação Oswaldo Cruz, Fiocruz Rondônia, and Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Porto Velho, Rondônia, Brazil
| | - Marcela Cristina S Silva
- Fundação Oswaldo Cruz, Fiocruz Rondônia, and Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Porto Velho, Rondônia, Brazil
| | | | | | | | | | | | - Andreimar M Soares
- Fundação Oswaldo Cruz, Fiocruz Rondônia, and Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Porto Velho, Rondônia, Brazil
| | - Juliana P Zuliani
- Fundação Oswaldo Cruz, Fiocruz Rondônia, and Instituto Nacional de Ciência e Tecnologia em Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Porto Velho, Rondônia, Brazil; Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil
| | - Rodrigo G Stabeli
- Plataforma Bi-Institucional de Medicina Translacional (Fiocruz-USP), Ribeirão Preto, São Paulo, Brazil
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20
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Ubbiali D, Orlando M, Kovačič M, Iacobucci C, Semrau MS, Bajc G, Fortuna S, Ilc G, Medagli B, Oloketuyi S, Storici P, Sinz A, Grandori R, de Marco A. An anti-HER2 nanobody binds to its antigen HER2 via two independent paratopes. Int J Biol Macromol 2021; 182:502-511. [PMID: 33848543 DOI: 10.1016/j.ijbiomac.2021.04.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 03/10/2021] [Accepted: 04/05/2021] [Indexed: 01/02/2023]
Abstract
High-resolution structural data of complexes between antibodies and membrane receptors still represent a demanding task. In this study, we used complementary sets of experimental data to obtain a structural model of the complex formed by the human epidermal growth factor receptor 2 (HER2) and its specific nanobody A10. First we identified by NMR the residues that bind or rearrange as a consequence of the complex formation. In parallel, the complex was cross-linked, digested and the resulting peptides were characterized by mass-spectrometry to define maximal distance restraints between HER2 and A10 amino acids in their complex. These independent datasets guided a docking process, refined by molecular dynamics simulations, to develop a model of the complex and estimate per-residue free-energy contributions. Such a model explains the experimental data and identifies a second, non-canonical paratope, located in the region opposite to the conventional nanobody paratope, formed by the hypervariable loop regions LH1 and LH3. Both paratopes contributed substantially to the overall affinity by binding to independent HER2 epitopes. Nanobody mutants with substitution of key interaction residues, as indicated by the model, possess significantly lower affinity for HER2. This is the first described case of a "natural" biparatopic nanobody, directly selected by in-vitro panning.
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Affiliation(s)
- Daniele Ubbiali
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Marco Orlando
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy; Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100 Varese, Italy
| | - Matic Kovačič
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
| | - Claudio Iacobucci
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Marta S Semrau
- Structural Biology Lab, Elettra Sincrotrone Trieste S.C.p.A., 34149, Basovizza, Trieste, Italy; CIBIO, Centre for Integrative Biology, University of Trento, via Sommarive 9, Povo 38123, Italy
| | - Gregor Bajc
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia
| | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Gregor Ilc
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
| | - Barbara Medagli
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Sandra Oloketuyi
- Lab of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, 5000 Rožna Dolina, Nova Gorica, Slovenia
| | - Paola Storici
- Structural Biology Lab, Elettra Sincrotrone Trieste S.C.p.A., 34149, Basovizza, Trieste, Italy
| | - Andrea Sinz
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Rita Grandori
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Ario de Marco
- Lab of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, 5000 Rožna Dolina, Nova Gorica, Slovenia.
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21
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Soler MA, Medagli B, Wang J, Oloketuyi S, Bajc G, Huang H, Fortuna S, de Marco A. Effect of Humanizing Mutations on the Stability of the Llama Single-Domain Variable Region. Biomolecules 2021; 11:biom11020163. [PMID: 33530572 PMCID: PMC7911018 DOI: 10.3390/biom11020163] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/21/2021] [Accepted: 01/24/2021] [Indexed: 11/24/2022] Open
Abstract
In vivo clinical applications of nanobodies (VHHs) require molecules that induce minimal immunoresponse and therefore possess sequences as similar as possible to the human VH domain. Although the relative sequence variability in llama nanobodies has been used to identify scaffolds with partially humanized signature, the transformation of the Camelidae hallmarks in the framework2 still represents a major problem. We assessed a set of mutants in silico and experimentally to elucidate what is the contribution of single residues to the VHH stability and how their combinations affect the mutant nanobody stability. We described at molecular level how the interaction among residues belonging to different structural elements enabled a model llama nanobody (C8WT, isolated from a naïve library) to be functional and maintain its stability, despite the analysis of its primary sequence would classify it as aggregation-prone. Five chimeras formed by grafting CDRs isolated from different nanobodies into C8WT scaffold were successfully expressed as soluble proteins and both tested clones preserved their antigen binding specificity. We identified a nanobody with human hallmarks that seems suitable for humanizing selected camelid VHHs by grafting heterologous CDRs in its scaffold and could serve for the preparation of a synthetic library of human-like single domains.
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Affiliation(s)
- Miguel A. Soler
- CONCEPT Lab, Italian Institute of Technology (IIT), 16152 Genova, Italy
- Correspondence: (M.A.S.); (A.d.M.); Tel.: +386-05-3315295 (A.d.M.); Fax: +386-05-90-99-722 (A.d.M.)
| | - Barbara Medagli
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, 34127 Trieste, Italy; (B.M.); (S.F.)
| | - Jiewen Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, China; (J.W.); (H.H.)
| | - Sandra Oloketuyi
- Lab of Environmental and Life Sciences, University of Nova Gorica, 5000 Rožna Dolina-Nova Gorica, Slovenia;
| | - Gregor Bajc
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia;
| | - He Huang
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, China; (J.W.); (H.H.)
| | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, 34127 Trieste, Italy; (B.M.); (S.F.)
| | - Ario de Marco
- Lab of Environmental and Life Sciences, University of Nova Gorica, 5000 Rožna Dolina-Nova Gorica, Slovenia;
- Correspondence: (M.A.S.); (A.d.M.); Tel.: +386-05-3315295 (A.d.M.); Fax: +386-05-90-99-722 (A.d.M.)
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Computational Evolution of Beta-2-Microglobulin Binding Peptides for Nanopatterned Surface Sensors. Int J Mol Sci 2021; 22:ijms22020812. [PMID: 33467468 PMCID: PMC7831021 DOI: 10.3390/ijms22020812] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/24/2020] [Accepted: 01/04/2021] [Indexed: 11/17/2022] Open
Abstract
The bottom-up design of smart nanodevices largely depends on the accuracy by which each of the inherent nanometric components can be functionally designed with predictive methods. Here, we present a rationally designed, self-assembled nanochip capable of capturing a target protein by means of pre-selected binding sites. The sensing elements comprise computationally evolved peptides, designed to target an arbitrarily selected binding site on the surface of beta-2-Microglobulin (β2m), a globular protein that lacks well-defined pockets. The nanopatterned surface was generated by an atomic force microscopy (AFM)-based, tip force-driven nanolithography technique termed nanografting to construct laterally confined self-assembled nanopatches of single stranded (ss)DNA. These were subsequently associated with an ssDNA-peptide conjugate by means of DNA-directed immobilization, therefore allowing control of the peptide's spatial orientation. We characterized the sensitivity of such peptide-containing systems against β2m in solution by means of AFM-based differential topographic imaging and surface plasmon resonance (SPR) spectroscopy. Our results show that the confined peptides are capable of specifically capturing β2m from the surface-liquid interface with micromolar affinity, hence providing a viable proof-of-concept for our approach to peptide design.
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de Marco A. Recombinant expression of nanobodies and nanobody-derived immunoreagents. Protein Expr Purif 2020; 172:105645. [PMID: 32289357 PMCID: PMC7151424 DOI: 10.1016/j.pep.2020.105645] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 04/06/2020] [Accepted: 04/09/2020] [Indexed: 12/12/2022]
Abstract
Antibody fragments for which the sequence is available are suitable for straightforward engineering and expression in both eukaryotic and prokaryotic systems. When produced as fusions with convenient tags, they become reagents which pair their selective binding capacity to an orthogonal function. Several kinds of immunoreagents composed by nanobodies and either large proteins or short sequences have been designed for providing inexpensive ready-to-use biological tools. The possibility to choose among alternative expression strategies is critical because the fusion moieties might require specific conditions for correct folding or post-translational modifications. In the case of nanobody production, the trend is towards simpler but reliable (bacterial) methods that can substitute for more cumbersome processes requiring the use of eukaryotic systems. The use of these will not disappear, but will be restricted to those cases in which the final immunoconstructs must have features that cannot be obtained in prokaryotic cells. At the same time, bacterial expression has evolved from the conventional procedure which considered exclusively the nanobody and nanobody-fusion accumulation in the periplasm. Several reports show the advantage of cytoplasmic expression, surface-display and secretion for at least some applications. Finally, there is an increasing interest to use as a model the short nanobody sequence for the development of in silico methodologies aimed at optimizing the yields, stability and affinity of recombinant antibodies. There is an increasing request for immunoreagents based on nanobodies. The multiplicity of their applications requires constructs with different structural complexity. Alternative expression methods are necessary to achieve such structural requirements. In silico optimization of nanobody biophysical characteristics becomes more and more reliable.
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Affiliation(s)
- Ario de Marco
- Laboratory for Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, S-5000, Nova Gorica, Slovenia.
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Oloketuyi S, Mazzega E, Zavašnik J, Pungjunun K, Kalcher K, de Marco A, Mehmeti E. Electrochemical immunosensor functionalized with nanobodies for the detection of the toxic microalgae Alexandrium minutum using glassy carbon electrode modified with gold nanoparticles. Biosens Bioelectron 2020; 154:112052. [PMID: 32056958 DOI: 10.1016/j.bios.2020.112052] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 01/22/2020] [Accepted: 01/24/2020] [Indexed: 12/28/2022]
Abstract
In this work an electrochemical immunosensor for the toxic microalgae Alexandrium minutum (A. minutum AL9T) detection is described. A glassy carbon electrode (GCE) was modified by depositing gold nanoparticles followed by L-cysteine for obtaining a self-assembled monolayer. The SpyTagged nanobody C1, specific for the A. minutum toxic strain AL9T, was then covalently immobilized via SpyCatcher on the surface of the modified electrode and used for the selective capture of such microalgae strain. Electrochemical impedance spectroscopy (EIS) was used for the quantification of A. minutum cells present in water samples by measuring the charge-transfer resistance changes of the electrode with a hexacyanoferrate probe. Each electrode modification step was accompanied by cyclic voltammetry (CV) and scanning electron microscopy (SEM). The immunosensor provided highly reproducible data, was simple to fabricate at low cost, exhibited higher sensitivity than previously described alternative diagnostic methods and showed a broad linear range between 103 and 109 cells L-1 with detection limit of 3 × 103 cells L-1 of A. minutum AL9T. The immunosensor was successfully applied to quantify A. minutum AL9T in seawater and brackish water samples proving that it can be used for early detection of harmful microalgae without the necessity of pre-concentration or dialysis steps.
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Affiliation(s)
- Sandra Oloketuyi
- Laboratory of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, SI-5000, Rožna Dolina (Nova Gorica), Slovenia
| | - Elisa Mazzega
- Laboratory of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, SI-5000, Rožna Dolina (Nova Gorica), Slovenia
| | - Janez Zavašnik
- Department for Nanostructured Materials, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - Kingkan Pungjunun
- Electrochemistry and Optical Spectroscopy Center of Excellence (EOSCE), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, 10330, Thailand
| | - Kurt Kalcher
- Institute of Chemistry, Analytical Chemistry, Karl-Franzens University, Universitätsplatz 1, Graz, A-8010, Austria
| | - Ario de Marco
- Laboratory of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, SI-5000, Rožna Dolina (Nova Gorica), Slovenia.
| | - Eda Mehmeti
- Institute of Chemistry, Analytical Chemistry, Karl-Franzens University, Universitätsplatz 1, Graz, A-8010, Austria.
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Veggiani G, Giabbai B, Semrau MS, Medagli B, Riccio V, Bajc G, Storici P, de Marco A. Comparative analysis of fusion tags used to functionalize recombinant antibodies. Protein Expr Purif 2020; 166:105505. [DOI: 10.1016/j.pep.2019.105505] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 09/20/2019] [Accepted: 09/25/2019] [Indexed: 02/06/2023]
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26
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Soler MA, Medagli B, Semrau MS, Storici P, Bajc G, de Marco A, Laio A, Fortuna S. A consensus protocol for the in silico optimisation of antibody fragments. Chem Commun (Camb) 2019; 55:14043-14046. [PMID: 31690899 DOI: 10.1039/c9cc06182g] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We present an in silico mutagenetic protocol for improving the binding affinity of single domain antibodies (or nanobodies, VHHs). The method iteratively attempts random mutations in the interacting region of the protein and evaluates the resulting binding affinity towards the target by scoring, with a collection of scoring functions, short explicit solvent molecular dynamics trajectories of the binder-target complexes. The acceptance/rejection of each attempted mutation is carried out by a consensus decision-making algorithm, which considers all individual assessments derived from each scoring function. The method was benchmarked by evolving a single complementary determining region (CDR) of an anti-HER2 VHH hit obtained by direct panning of a phage display library. The optimised VHH mutant showed significantly enhanced experimental affinity with respect to the original VHH it matured from. The protocol can be employed as it is for the optimization of peptides, antibody fragments, and (given enough computational power) larger antibodies.
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Affiliation(s)
- Miguel A Soler
- International School for Advanced Studies (SISSA), Via Bonomea 265, 34136, Trieste, Italy.
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27
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Forouzesh M, Askerovich Mamedov A, Pourabadeh A, Hosseini M, Hosseinzadeh G, Arezumand R. Rational MD simulations for improvement the affinity of nanobody against PlGF (placenta growth factor): mutagenesis based on electrostatic interactions. J Biomol Struct Dyn 2019; 38:3750-3756. [PMID: 31524085 DOI: 10.1080/07391102.2019.1664327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
AbbreviationsCOMcenter of mass distanceMDmolecular dynamicsMM-PBSAMolecular Mechanics Poisson-Boltzmann Surface AreaNbnanobodyPlGFplacenta growth factorRgradius of gyrationRMSDroot mean-square deviationSASAsolvent-accessible surface areaVEGFvascular endothelial growth factor.
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Affiliation(s)
- Mehdi Forouzesh
- Legal Medicine Organization of Iran, Legal Medicine Research Center, Legal Medicine Organization, Tehran, Iran
| | - Adil Askerovich Mamedov
- Department of Pediatric Dentistry and Orthodontics, I.M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - Amirasad Pourabadeh
- Department of Textile Engineering, Islamic Azad University, Yazd Branch, Yazd, Iran
| | - Mojgan Hosseini
- Department of Science, Islamshahr Branch, Islamic Azad University, Islamshahr, Tehran, Iran
| | | | - Roghaye Arezumand
- Department of Medical Biotechnology and Molecular Science, North Khorasan University of Medical Science, Bojnurd, Iran
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28
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Homology Modeling-Based in Silico Affinity Maturation Improves the Affinity of a Nanobody. Int J Mol Sci 2019; 20:ijms20174187. [PMID: 31461846 PMCID: PMC6747709 DOI: 10.3390/ijms20174187] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/21/2019] [Accepted: 08/22/2019] [Indexed: 01/08/2023] Open
Abstract
Affinity maturation and rational design have a raised importance in the application of nanobody (VHH), and its unique structure guaranteed these processes quickly done in vitro. An anti-CD47 nanobody, Nb02, was screened via a synthetic phage display library with 278 nM of KD value. In this study, a new strategy based on homology modeling and Rational Mutation Hotspots Design Protocol (RMHDP) was presented for building a fast and efficient platform for nanobody affinity maturation. A three-dimensional analytical structural model of Nb02 was constructed and then docked with the antigen, the CD47 extracellular domain (CD47ext). Mutants with high binding affinity are predicted by the scoring of nanobody-antigen complexes based on molecular dynamics trajectories and simulation. Ultimately, an improved mutant with an 87.4-fold affinity (3.2 nM) and 7.36 °C higher thermal stability was obtained. These findings might contribute to computational affinity maturation of nanobodies via homology modeling using the recent advancements in computational power. The add-in of aromatic residues which formed aromatic-aromatic interaction plays a pivotal role in affinity and thermostability improvement. In a word, the methods used in this study might provide a reference for rapid and efficient in vitro affinity maturation of nanobodies.
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29
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Ochoa R, Laio A, Cossio P. Predicting the Affinity of Peptides to Major Histocompatibility Complex Class II by Scoring Molecular Dynamics Simulations. J Chem Inf Model 2019; 59:3464-3473. [PMID: 31290667 DOI: 10.1021/acs.jcim.9b00403] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Predicting the binding affinity of peptides able to interact with major histocompatibility complex (MHC) molecules is a priority for researchers working in the identification of novel vaccines candidates. Most available approaches are based on the analysis of the sequence of peptides of known experimental affinity. However, for MHC class II receptors, these approaches are not very accurate, due to the intrinsic flexibility of the complex. To overcome these limitations, we propose to estimate the binding affinity of peptides bound to an MHC class II by averaging the score of the configurations from finite-temperature molecular dynamics simulations. The score is estimated for 18 different scoring functions, and we explored the optimal manner for combining them. To test the predictions, we considered eight peptides of known binding affinity. We found that six scoring functions correlate with the experimental ranking of the peptides significantly better than the others. We then assessed a set of techniques for combining the scoring functions by linear regression and logistic regression. We obtained a maximum accuracy of 82% for the predicted sign of the binding affinity using a logistic regression with optimized weights. These results are potentially useful to improve the reliability of in silico protocols to design high-affinity binding peptides for MHC class II receptors.
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Affiliation(s)
- Rodrigo Ochoa
- Biophysics of Tropical Diseases, Max Planck Tandem Group , University of Antioquia , 050010 Medellin , Colombia
| | - Alessandro Laio
- International School for Advanced Studies (SISSA) , Via Bonomea 265 , 34136 Trieste , Italy.,The Abdus Salam International Centre for Theoretical Physics (ICTP) , Strada Costiera 11 , 34151 Trieste , Italy
| | - Pilar Cossio
- Biophysics of Tropical Diseases, Max Planck Tandem Group , University of Antioquia , 050010 Medellin , Colombia.,Department of Theoretical Biophysics , Max Planck Institute of Biophysics , 60438 Frankfurt am Main , Germany
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30
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Ochoa R, Soler MA, Laio A, Cossio P. Assessing the capability of in silico mutation protocols for predicting the finite temperature conformation of amino acids. Phys Chem Chem Phys 2018; 20:25901-25909. [PMID: 30289133 DOI: 10.1039/c8cp03826k] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Mutation protocols are a key tool in computational biophysics for modelling unknown side chain conformations. In particular, these protocols are used to generate the starting structures for molecular dynamics simulations. The accuracy of the initial side chain and backbone placement is crucial to obtain a stable and quickly converging simulation. In this work, we assessed the performance of several mutation protocols in predicting the most probable conformer observed in finite temperature molecular dynamics simulations for a set of protein-peptide crystals differing only by single-point mutations in the peptide sequence. Our results show that several programs which predict well the crystal conformations fail to predict the most probable finite temperature configuration. Methods relying on backbone-dependent rotamer libraries have, in general, a better performance, but even the best protocol fails in predicting approximately 30% of the mutations.
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Affiliation(s)
- Rodrigo Ochoa
- Biophysics of Tropical Diseases, Max Planck Tandem Group, University of Antioquia, Medellin, Colombia.
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