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Li J, Lyu C, An R, Wang D. Interaction Between SARS-CoV-2 Spike Protein S1 Subunit and Oyster Heat Shock Protein 70. Food Environ Virol 2024:10.1007/s12560-024-09599-y. [PMID: 38635140 DOI: 10.1007/s12560-024-09599-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 03/19/2024] [Indexed: 04/19/2024]
Abstract
There is growing evidence that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contaminates the marine environment and is bioaccumulated in filter-feeding shellfish. Previous study shows the Pacific oyster tissues can bioaccumulate the SARS-CoV-2, and the oyster heat shock protein 70 (oHSP70) may play as the primary attachment receptor to bind SARS-CoV-2's recombinant spike protein S1 subunit (rS1). However, detailed information about the interaction between rS1 and oHSP70 is still unknown. In this study, we confirmed that the affinity of recombinant oHSP70 (roHSP70) for rS1 (KD = 20.4 nM) is comparable to the receptor-binding affinity of rACE2 for rS1 (KD = 16.7 nM) by surface plasmon resonance (SPR)-based Biacore and further validated by enzyme-linked immunosorbent assay (ELISA). Three truncated proteins (roHSP70-N/C/M) and five mutated proteins (p.I229del, p.D457del, p.V491_K495del, p.K556I, and p.ΣroHSP70) were constructed according to the molecular docking results. All three truncated proteins have significantly lower affinity for rS1 than the full-length roHSP70, indicating that all three segments of roHSP70 are involved in binding to rS1. Further, the results of SPR and ELISA showed that all five mutant proteins had significantly lower affinity for rS1 than roHSP70, suggesting that amino acids at these sites are involved in binding to rS1. This study provides a preliminary theoretical basis for the bioaccumulation of SARS-CoV-2 in oyster tissues or using roHSP70 as the capture unit to selectively enrich virus particles for detection.
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Affiliation(s)
- Jingwen Li
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Chenang Lyu
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Ran An
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Dapeng Wang
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
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2
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Petitjean II, Tran QD, Goutou A, Kabir Z, Wiche G, Leduc C, Koenderink GH. Reconstitution of cytolinker-mediated crosstalk between actin and vimentin. Eur J Cell Biol 2024; 103:151403. [PMID: 38503131 DOI: 10.1016/j.ejcb.2024.151403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 03/06/2024] [Accepted: 03/06/2024] [Indexed: 03/21/2024] Open
Abstract
Cell shape and motility are determined by the cytoskeleton, an interpenetrating network of actin filaments, microtubules, and intermediate filaments. The biophysical properties of each filament type individually have been studied extensively by cell-free reconstitution. By contrast, the interactions between the three cytoskeletal networks are relatively unexplored. They are coupled via crosslinkers of the plakin family such as plectin. These are challenging proteins for reconstitution because of their giant size and multidomain structure. Here we engineer a recombinant actin-vimentin crosslinker protein called 'ACTIF' that provides a minimal model system for plectin, recapitulating its modular design with actin-binding and intermediate filament-binding domains separated by a coiled-coil linker for dimerisation. We show by fluorescence and electron microscopy that ACTIF has a high binding affinity for vimentin and actin and creates mixed actin-vimentin bundles. Rheology measurements show that ACTIF-mediated crosslinking strongly stiffens actin-vimentin composites. Finally, we demonstrate the modularity of this approach by creating an ACTIF variant with the intermediate filament binding domain of Adenomatous Polyposis Coli. Our protein engineering approach provides a new cell-free system for the biophysical characterization of intermediate filament-binding crosslinkers and for understanding the mechanical synergy between actin and vimentin in mesenchymal cells.
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Affiliation(s)
- Irene Istúriz Petitjean
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Quang D Tran
- CNRS, Institut Jacques Monod, Université Paris Cité, Paris F-75013, France
| | - Angeliki Goutou
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Zima Kabir
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Gerhard Wiche
- Max Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
| | - Cécile Leduc
- CNRS, Institut Jacques Monod, Université Paris Cité, Paris F-75013, France.
| | - Gijsje H Koenderink
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands.
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3
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Santos-López J, Gómez S, Fernández FJ, Vega MC. Protein-Protein Binding Kinetics by Biolayer Interferometry. Adv Exp Med Biol 2024; 3234:73-88. [PMID: 38507201 DOI: 10.1007/978-3-031-52193-5_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
The specific kinetics and thermodynamics of protein-protein interactions underlie the molecular mechanisms of cellular functions; hence the characterization of these interaction parameters is central to the quantitative understanding of physiological and pathological processes. Many methods have been developed to study protein-protein interactions, which differ in various features including the interaction detection principle, the sensitivity, whether the method operates in vivo, in vitro, or in silico, the temperature control, the use of labels, immobilization, the amount of sample required, the number of measurements that can be accomplished simultaneously, or the cost. Bio-Layer Interferometry (BLI) is a label-free biophysical method to measure the kinetics of protein-protein interactions. Label-free interaction assays are a broad family of methods that do not require protein modifications (other than immobilization) or labels such as fusions with fluorescent proteins or transactivating domains or chemical modifications like biotinylation or reaction with radionuclides. Besides BLI, other label-free techniques that are widely used for determining protein-protein interactions include surface plasmon resonance (SPR), thermophoresis, and isothermal titration calorimetry (ITC), among others.
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Affiliation(s)
- Jorge Santos-López
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), Madrid, Spain
| | - Sara Gómez
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), Madrid, Spain
- Universidad Europea de Madrid, Madrid, Spain
| | | | - M Cristina Vega
- Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), Madrid, Spain.
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4
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Baardsnes J, Paul-Roc B. SARS-CoV-2S-Protein-Ace2 Binding Analysis Using Surface Plasmon Resonance. Methods Mol Biol 2024; 2762:71-87. [PMID: 38315360 DOI: 10.1007/978-1-0716-3666-4_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Surface plasmon resonance (SPR) allows for the label-free determination of the binding affinity and rate constants of bimolecular interactions. Here, we describe the method used for the analysis of the Ace2-SARS-CoV2 S-protein interaction using indirect capture of the S-protein onto the SPR surface, and flowing monomeric Ace2. This method will allow for the determination of the rate constants for affinity, with additional analysis that is achievable using S-protein capture levels in conjunction with the sensorgram response for relative activity benchmarking.
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Affiliation(s)
- Jason Baardsnes
- Quality Attributes and Characterization, Human Health Therapeutics, National Research Council Canada, Montréal, QC, Canada.
| | - Béatrice Paul-Roc
- Quality Attributes and Characterization, Human Health Therapeutics, National Research Council Canada, Montréal, QC, Canada
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Tekwani Movellan K, Wegstroth M, Overkamp K, Leonov A, Becker S, Andreas LB. Real-time tracking of drug binding to influenza A M2 reveals a high energy barrier. J Struct Biol X 2023; 8:100090. [PMID: 37363040 PMCID: PMC10285276 DOI: 10.1016/j.yjsbx.2023.100090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 05/18/2023] [Accepted: 06/02/2023] [Indexed: 06/28/2023] Open
Abstract
The drug Rimantadine binds to two different sites in the M2 protein from influenza A, a peripheral site and a pore site that is the primary site of efficacy. It remained enigmatic that pore binding did not occur in certain detergent micelles, and in particular incomplete binding was observed in a mixture of lipids selected to match the viral membrane. Here we show that two effects are responsible, namely changes in the protein upon pore binding that prevented detergent solubilization, and slow binding kinetics in the lipid samples. Using 55-100 kHz magic-angle spinning NMR, we characterize kinetics of drug binding in three different lipid environments: DPhPC, DPhPC with cholesterol and viral mimetic membrane lipid bilayers. Slow pharmacological binding kinetics allowed the characterization of spectral changes associated with non-specific binding to the protein periphery in the kinetically trapped pore-apo state. Resonance assignments were determined from a set of proton-detected 3D spectra. Chemical shift changes associated with functional binding in the pore of M2 were tracked in real time in order to estimate the activation energy. The binding kinetics are affected by pH and the lipid environment and in particular cholesterol. We found that the imidazole-imidazole hydrogen bond at residue histidine 37 is a stable feature of the protein across several lipid compositions. Pore binding breaks the imidazole-imidazole hydrogen bond and limits solubilization in DHPC detergent.
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Nguyen K, Li K, Flores K, Tomaras GD, Dennison SM, McCarthy JM. Parameter estimation and identifiability analysis for a bivalent analyte model of monoclonal antibody-antigen binding. Anal Biochem 2023; 679:115263. [PMID: 37549723 PMCID: PMC10511885 DOI: 10.1016/j.ab.2023.115263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 07/10/2023] [Accepted: 07/23/2023] [Indexed: 08/09/2023]
Abstract
Surface plasmon resonance (SPR) is an extensively used technique to characterize antigen-antibody interactions. Affinity measurements by SPR typically involve testing the binding of antigen in solution to monoclonal antibodies (mAbs) immobilized on a chip and fitting the kinetics data using 1:1 Langmuir binding model to derive rate constants. However, when it is necessary to immobilize antigens instead of the mAbs, a bivalent analyte (1:2) binding model is required for kinetics analysis. This model is lacking in data analysis packages associated with high throughput SPR instruments and the packages containing this model do not explore multiple local minima and parameter identifiability issues that are common in non-linear optimization. Therefore, we developed a method to use a system of ordinary differential equations for analyzing 1:2 binding kinetics data. Salient features of this method include a grid search on parameter initialization and a profile likelihood approach to determine parameter identifiability. Using this method we found a non-identifiable parameter in data set collected under the standard experimental design. A simulation-guided improved experimental design led to reliable estimation of all rate constants. The method and approach developed here for analyzing 1:2 binding kinetics data will be valuable for expeditious therapeutic antibody discovery research.
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Affiliation(s)
- Kyle Nguyen
- Biomathematics Graduate Program, North Carolina State University, Raleigh, 27607, NC, USA; Center for Research in Scientific Computation, North Carolina State University, Raleigh, 27607, NC, USA.
| | - Kan Li
- Center for Human Systems Immunology, Duke University, Durham, 27701, NC, USA; Department of Surgery, Duke University, Durham, 27710, NC, USA
| | - Kevin Flores
- Center for Research in Scientific Computation, North Carolina State University, Raleigh, 27607, NC, USA; Department of Mathematics, North Carolina State University, Raleigh, 27607, NC, USA
| | - Georgia D Tomaras
- Center for Human Systems Immunology, Duke University, Durham, 27701, NC, USA; Department of Surgery, Duke University, Durham, 27710, NC, USA; Department of Integrative Immunobiology, Duke University, Durham, 27710, NC, USA; Department of Molecular Genetics and Microbiology, Duke University, Durham, 27710, NC, USA; Duke Human Vaccine Institute, Duke University, Durham, 27710, NC, USA
| | - S Moses Dennison
- Center for Human Systems Immunology, Duke University, Durham, 27701, NC, USA; Department of Surgery, Duke University, Durham, 27710, NC, USA
| | - Janice M McCarthy
- Center for Human Systems Immunology, Duke University, Durham, 27701, NC, USA; Department of Biostatistics and Bioinformatics, Duke University, Durham, 27710, NC, USA
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Guzzetti S, Morentin Gutierrez P. An integrated modelling approach for targeted degradation: insights on optimization, data requirements and PKPD predictions from semi- or fully-mechanistic models and exact steady state solutions. J Pharmacokinet Pharmacodyn 2023; 50:327-349. [PMID: 37120680 PMCID: PMC10460745 DOI: 10.1007/s10928-023-09857-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/28/2023] [Indexed: 05/01/2023]
Abstract
The value of an integrated mathematical modelling approach for protein degraders which combines the benefits of traditional turnover models and fully mechanistic models is presented. Firstly, we show how exact solutions of the mechanistic models of monovalent and bivalent degraders can provide insight on the role of each system parameter in driving the pharmacological response. We show how on/off binding rates and degradation rates are related to potency and maximal effect of monovalent degraders, and how such relationship can be used to suggest a compound optimization strategy. Even convoluted exact steady state solutions for bivalent degraders provide insight on the type of observations required to ensure the predictive capacity of a mechanistic approach. Specifically for PROTACs, the structure of the exact steady state solution suggests that the total remaining target at steady state, which is easily accessible experimentally, is insufficient to reconstruct the state of the whole system at equilibrium and observations on different species (such as binary/ternary complexes) are necessary. Secondly, global sensitivity analysis of fully mechanistic models for PROTACs suggests that both target and ligase baselines (actually, their ratio) are the major sources of variability in the response of non-cooperative systems, which speaks to the importance of characterizing their distribution in the target patient population. Finally, we propose a pragmatic modelling approach which incorporates the insights generated with fully mechanistic models into simpler turnover models to improve their predictive ability, hence enabling acceleration of drug discovery programs and increased probability of success in the clinic.
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Affiliation(s)
- Sofia Guzzetti
- DMPK, Research and Early Development, Oncology R&D, AstraZeneca, Cambridge, UK
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8
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Colin P, Ringe RP, Yasmeen A, Ozorowski G, Ketas TJ, Lee WH, Ward AB, Moore JP, Klasse PJ. Conformational antigenic heterogeneity as a cause of the persistent fraction in HIV-1 neutralization. Retrovirology 2023; 20:9. [PMID: 37244989 DOI: 10.1186/s12977-023-00624-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 05/15/2023] [Indexed: 05/29/2023] Open
Abstract
BACKGROUND Neutralizing antibodies (NAbs) protect against HIV-1 acquisition in animal models and show promise in treatment of infection. They act by binding to the viral envelope glycoprotein (Env), thereby blocking its receptor interactions and fusogenic function. The potency of neutralization is largely determined by affinity. Less well explained is the persistent fraction, the plateau of remaining infectivity at the highest antibody concentrations. RESULTS We observed different persistent fractions for neutralization of pseudovirus derived from two Tier-2 isolates of HIV-1, BG505 (Clade A) and B41 (Clade B): it was pronounced for B41 but not BG505 neutralization by NAb PGT151, directed to the interface between the outer and transmembrane subunits of Env, and negligible for either virus by NAb PGT145 to an apical epitope. Autologous neutralization by poly- and monoclonal NAbs from rabbits immunized with soluble native-like B41 trimer also left substantial persistent fractions. These NAbs largely target a cluster of epitopes lining a hole in the dense glycan shield of Env around residue 289. We partially depleted B41-virion populations by incubating them with PGT145- or PGT151-conjugated beads. Each depletion reduced the sensitivity to the depleting NAb and enhanced it to the other. Autologous neutralization by the rabbit NAbs was decreased for PGT145-depleted and enhanced for PGT151-depleted B41 pseudovirus. Those changes in sensitivity encompassed both potency and the persistent fraction. We then compared soluble native-like BG505 and B41 Env trimers affinity-purified by each of three NAbs: 2G12, PGT145, or PGT151. Surface plasmon resonance showed differences among the fractions in antigenicity, including kinetics and stoichiometry, congruently with the differential neutralization. The large persistent fraction after PGT151 neutralization of B41 was attributable to low stoichiometry, which we explained structurally by clashes that the conformational plasticity of B41 Env causes. CONCLUSION Distinct antigenic forms even of clonal HIV-1 Env, detectable among soluble native-like trimer molecules, are distributed over virions and may profoundly mold neutralization of certain isolates by certain NAbs. Affinity purifications with some antibodies may yield immunogens that preferentially expose epitopes for broadly active NAbs, shielding less cross-reactive ones. NAbs reactive with multiple conformers will together reduce the persistent fraction after passive and active immunization.
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Affiliation(s)
- Philippe Colin
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, 62 , New York, NY, 10065, USA
- Toulouse Institute for Infectious and Inflammatory Diseases, Infinity, Université de Toulouse, CNRS, INSERM, UPS, Toulouse, France
| | - Rajesh P Ringe
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, 62 , New York, NY, 10065, USA
- Virology Unit, Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Anila Yasmeen
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, 62 , New York, NY, 10065, USA
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, Consortium for HIV Vaccine 14 Development (CHAVD), The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Thomas J Ketas
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, 62 , New York, NY, 10065, USA
| | - Wen-Hsin Lee
- Department of Integrative Structural and Computational Biology, Consortium for HIV Vaccine 14 Development (CHAVD), The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, Consortium for HIV Vaccine 14 Development (CHAVD), The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - John P Moore
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, 62 , New York, NY, 10065, USA
| | - P J Klasse
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, 1300 York Avenue, 62 , New York, NY, 10065, USA.
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Beitzinger C, Kronhardt A, Benz R. Chloroquine-analogues block anthrax protective antigen channels in steady-state and kinetic studies. Toxicology 2023; 492:153547. [PMID: 37201861 DOI: 10.1016/j.tox.2023.153547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/11/2023] [Accepted: 05/15/2023] [Indexed: 05/20/2023]
Abstract
The tripartite anthrax toxin from Bacillus anthracis represents the prototype of A-B type of toxins, where the effector A (an enzymatic subunit) is transported with the help of a binding component B into a target cell. Anthrax toxin consists of three different molecules, two effectors, lethal factor (LF) and edema factor (EF) and the binding component also known as protective antigen (PA). PA forms heptamers or octamers following binding to host cell's receptors and mediates the translocation of the effectors into the cytosol via the endosomal pathway. The cation-selective PA63-channel is able to reconstitute in lipid membranes and can be blocked by chloroquine and other heterocyclic compounds. This suggests that the PA63-channel contains a binding site for quinolines. In this study, we investigated the structure-function relationship of different quinolines for the block of the PA63-channel. The affinity of the different chloroquine analogues to the PA63-channel as provided by the equilibrium dissociation constant was measured using titrations. Some quinolines had a much higher affinity to the PA63-channel than chloroquine itself. We also performed ligand-induced current noise measurements using fast Fourier transformation to get insight in the kinetics of the binding of some quinolines to the PA63-channel. The on-rate constants of ligand binding were around 108M-1·s-1 at 150mM KCl and were only little dependent on the individual quinoline. The off-rates varied between 4s-1 and 160s-1 and depended much more on the structure of the molecules than the on-rate constants. The possible use of the 4-aminoquinolines as a therapy is discussed.
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Affiliation(s)
- Christoph Beitzinger
- Rudolf Virchow Center, Research Center for Experimental Biomedicine, University of Würzburg, Versbacher Straße 9, 97078 Würzburg, Germany
| | - Angelika Kronhardt
- Rudolf Virchow Center, Research Center for Experimental Biomedicine, University of Würzburg, Versbacher Straße 9, 97078 Würzburg, Germany
| | - Roland Benz
- Science Faculty, Constructor University Bremen, Campus-Ring 1, 28759 Bremen, Germany.
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Knockenhauer KE, Copeland RA. The Importance of Binding Kinetics and Drug-Target Residence Time in Pharmacology. Br J Pharmacol 2023. [PMID: 37160660 DOI: 10.1111/bph.16104] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/19/2023] [Accepted: 04/27/2023] [Indexed: 05/11/2023] Open
Abstract
A dominant assumption of pharmacology throughout the 20th century has been that in vivo target occupancy - and attendant pharmacodynamics - depends on the systemic concentration of drug relative to the equilibrium dissociation constant for the drug-target complex. In turn, the duration of pharmacodynamics is temporally linked to the systemic pharmacokinetics of the drug. Yet, there are many examples of drugs for which pharmacodynamic effect endures long after the systemic concentration of drug has waned to (equilibrium) insignificant levels. To reconcile such data, the drug-target residence time model was formulated, positing that it is the lifetime (or residence time) of the binary drug-target complex, and not its equilibrium affinity per se, that determines the extent and duration of drug pharmacodynamics. Here we review this model, its evolution over time, and its applications to natural ligand-macromolecule biology and synthetic drug-target pharmacology.
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Affiliation(s)
| | - Robert A Copeland
- Accent Therapeutics, Inc., 65 Hayden Ave., Lexington, MA, USA, 02421
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11
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Cleaver S, Gardner M, Barlow A, Ferrari E, Soloviev M. Fast Protocols for Characterizing Antibody-Peptide Binding. Methods Mol Biol 2023; 2578:83-101. [PMID: 36152282 DOI: 10.1007/978-1-0716-2732-7_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Microarray assay formats gained popularity in the 1990s, first implemented in DNA-based arrays but later adopted for use with proteins, namely antibodies, peptides, low molecular weight (LMW) molecules, such as lipids, and even tissues. In nucleic acid-based affinity assays and arrays, but not in protein or peptide arrays, the specificity and affinity of complementary strand interactions can be deduced from or adjusted through modifications to the nucleotide sequence. Arrays of LMW molecules are characterized by largely uniform but low binding affinities. Multiplexed protein-based affinity assays, such as microarrays, might present an additional challenge due to heterogeneity of antigen properties and of their binding affinities. The use of peptides instead of proteins reduces physical heterogeneity of these reagents through either the widened peptide selection options or rational sequence engineering. However, rational engineering of binding affinities remains an unmet need, and peptide-binding affinities to the respective antipeptide antibodies could vary by orders of magnitude. Hence, multiplexing of such assays by using a microarray format and data analysis and interpretation requires some knowledge of their binding affinities. Low-throughput binding assays to characterize such peptide-antipeptide antibodies interactions are widely available, but scaling-up of traditional protein- and peptide-binding assays might present practical challenges. Here, we describe fast label-free practical approach especially suitable for estimating peptide-binding affinities. The method in question relies on commercially available biolayer interferometry-based equipment with a protocol which can be easily scaled-up, subject to user needs and equipment availability.
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Affiliation(s)
- Sophie Cleaver
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey, UK
| | - Matthew Gardner
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey, UK
| | - Anthony Barlow
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey, UK
| | - Enrico Ferrari
- School of Life Sciences, University of Lincoln, Lincoln, UK
| | - Mikhail Soloviev
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey, UK.
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Rammauro F, Carrión F, Olivero-Deibe N, Fló M, Ferreira A, Pritsch O, Bianchi S. Humoral immune response characterization of heterologous prime-boost vaccination with CoronaVac and BNT162b2. Vaccine 2022; 40:5189-5196. [PMID: 35907676 PMCID: PMC9352561 DOI: 10.1016/j.vaccine.2022.07.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 07/06/2022] [Accepted: 07/19/2022] [Indexed: 12/22/2022]
Abstract
Background Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has proven to be a successful strategy for prevent severe infections. CoronaVac and BNT162b2 are the most used vaccines worldwide, but their use in heterologous vaccination schedules is still subjected to evaluation. Methods Fifty healthy individuals who received heterologous prime-boost vaccination with CoronaVac and BNT162b2 were enrolled in a post-vaccination serological follow-up longitudinal prospective study. We evaluated specific serum anti-receptor binding domain (RBD) IgG antibody levels, and their capacity to block RBD-ACE2 interaction with a surrogate neutralization assay. In 20 participants, we assessed antibody binding kinetics by surface plasmon resonance, and Fc-mediated functions by ADCC and ADCP reporter assays. Results Our baseline seronegative cohort, displayed seroconversion after two doses of CoronaVac and an important decrease in serum anti-RBD IgG antibodies levels 80 days post-second dose. These levels increased significantly early after the third dose with BNT162b2, but 73 days after the booster we found a new fall. Immunoglobulin functionalities showed a similar behavior. Conclusions The heterologous prime-boost vaccination with CoronaVac and BNT162b2 generated an impressive increase in serum anti-RBD specific antibody levels followed by a drop. Nevertheless, these titers remained well above those found in individuals only vaccinated with CoronaVac in the same elapsed time. Serum IgG levels showed high correlation with antibody binding analysis, their capacity to block RBD-ACE2 interaction, and Fc-effectors mechanisms. Our work sheds light on the humoral immune response to heterologous vaccination with CoronaVac and BNT162b2, to define a post-vaccination correlate of protection against SARS-CoV-2 infection and to discuss the scheduling of future vaccine boosters in general population.
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Affiliation(s)
- Florencia Rammauro
- Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay; Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Federico Carrión
- Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | | | - Martín Fló
- Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay; Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Ana Ferreira
- Unidad de Inmunología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Área Inmunología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Otto Pritsch
- Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay; Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Sergio Bianchi
- Laboratorio de Biomarcadores Moleculares, Departamento de Fisiopatología, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay; Laboratorio de Genómica Funcional, Institut Pasteur de Montevideo, Montevideo, Uruguay.
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13
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Thomas JHL, Lui L, Abell A, Tieu W, Somogyi AA, Bajic JE, Hutchinson MR. Toll-like receptors change morphine-induced antinociception, tolerance and dependence: Studies using male and female TLR and signalling gene KO mice. Brain Behav Immun 2022; 102:71-85. [PMID: 35131445 DOI: 10.1016/j.bbi.2022.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 12/22/2021] [Accepted: 02/01/2022] [Indexed: 12/13/2022] Open
Abstract
Toll-like receptors (TLR) have been proposed as a site of action that alters opioid pharmacodynamics. However, a comprehensive assessment of acute opioid antinociception, tolerance and withdrawal behaviours in genetic null mutant strains with altered innate immune signalling has not been performed. Nor has the impact of genetic deletion of TLR2/4 on high-affinity opioid receptor binding. Here we show that diminished TLR signalling potentiates acute morphine antinociception equally in male and female mice. However, only male TIR8 null mutant mice showed reduced morphine analgesia. Analgesic tolerance was prevented in TLR2 and TLR4 null mutants, but not MyD88 animals. Withdrawal behaviours were only protected in TLR2-/- mice. In silico docking simulations revealed opioid ligands bound preferentially to the LPS binding pocket of MD-2 rather than TLR4. There was no binding of [3H](-)-naloxone or [3H]diprenorphine to TLR4 in the concentrations explored. These data confirm that opioids have high efficacy activity at innate immune pattern recognition binding sites but do not bind to TLR4 and identify critical pathway and sex-specific effects of the complex innate immune signalling contributions to opioid pharmacodynamics. These data further support the behavioural importance of the TLR-opioid interaction but fail to demonstrate direct evidence for high-affinity binding of the TLR4 signalling complex to ligands.
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Affiliation(s)
- Jacob H L Thomas
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Liang Lui
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Andrew Abell
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; ARC Centre for Nanoscale BioPhotonics, University of Adelaide, SA 5005, Australia
| | - William Tieu
- Discipline of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Andrew A Somogyi
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia
| | - Juliana E Bajic
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; ARC Centre for Nanoscale BioPhotonics, University of Adelaide, SA 5005, Australia
| | - Mark R Hutchinson
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; ARC Centre for Nanoscale BioPhotonics, University of Adelaide, SA 5005, Australia.
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14
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Vlachodimou A, de Vries H, Pasoli M, Goudswaard M, Kim SA, Kim YC, Scortichini M, Marshall M, Linden J, Heitman LH, Jacobson KA, IJzerman AP. Kinetic profiling and functional characterization of 8-phenylxanthine derivatives as A 2B adenosine receptor antagonists. Biochem Pharmacol 2022; 200:115027. [PMID: 35395239 DOI: 10.1016/j.bcp.2022.115027] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/22/2022] [Accepted: 03/24/2022] [Indexed: 12/30/2022]
Abstract
A2B adenosine receptor (A2BAR) antagonists have therapeutic potential in inflammation-related diseases such as asthma, chronic obstructive pulmonary disease and cancer. However, no drug is currently clinically approved, creating a demand for research on novel antagonists. Over the last decade, the study of target binding kinetics, along with affinity and potency, has been proven valuable in early drug discovery stages, as it is associated with improved in vivo drug efficacy and safety. In this study, we report the synthesis and biological evaluation of a series of xanthine derivatives as A2BAR antagonists, including an isothiocyanate derivative designed to bind covalently to the receptor. All 28 final compounds were assessed in radioligand binding experiments, to evaluate their affinity and for those qualifying, kinetic binding parameters. Both structure-affinity and structure-kinetic relationships were derived, providing a clear relationship between affinity and dissociation rate constants. Two structurally similar compounds, 17 and 18, were further evaluated in a label-free assay due to their divergent kinetic profiles. An extended cellular response was associated with long A2BAR residence times. This link between a ligand's A2BAR residence time and its functional effect highlights the importance of binding kinetics as a selection parameter in the early stages of drug discovery.
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Affiliation(s)
- Anna Vlachodimou
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, the Netherlands
| | - Henk de Vries
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, the Netherlands
| | - Milena Pasoli
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, the Netherlands
| | - Miranda Goudswaard
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, the Netherlands
| | - Soon-Ai Kim
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, 9000 Rockville Pike, Bethesda, MD 20892, USA
| | - Yong-Chul Kim
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, 9000 Rockville Pike, Bethesda, MD 20892, USA
| | - Mirko Scortichini
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, 9000 Rockville Pike, Bethesda, MD 20892, USA
| | - Melissa Marshall
- Department of Internal Medicine and Molecular Physiology & Biological Physics, University of Virginia Health Science Center, Charlottesville, VA 22908, USA
| | - Joel Linden
- Department of Internal Medicine and Molecular Physiology & Biological Physics, University of Virginia Health Science Center, Charlottesville, VA 22908, USA
| | - Laura H Heitman
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, the Netherlands; Oncode Institute, Leiden, the Netherlands
| | - Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, 9000 Rockville Pike, Bethesda, MD 20892, USA.
| | - Adriaan P IJzerman
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, the Netherlands.
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15
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Jaiswal J, Dhayal M. Electrochemically differentiated human MSCs biosensing platform for quantification of nestin and β-III tubulin as whole-cell system. Biosens Bioelectron 2022; 206:114134. [PMID: 35276463 DOI: 10.1016/j.bios.2022.114134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/09/2022] [Accepted: 02/23/2022] [Indexed: 12/14/2022]
Abstract
Polydimethylsiloxane (PDMS) on ITO substrate was used to create a well with conducting surface to adhere human mesenchymal stem cells (hMSCs) and provide electrochemical stimulation for inducing their differentiation into neural-like cells. The cells that received electrochemical stimulation did not show any noticeable change in their viability and proliferation. The cell morphology of the differentiated hMSCs adherent on ITO showed outgrowth and elongation in one dimension, resembling neural-like cells. Immunocytochemistry assessment by quantifying the expression of nestin and β-III tubulin also confirmed the differentiation of hMSCs. These differentiated hMSCs adherent on ITO were used as electrochemical biosensing platform for differential pulse voltammetry (DPV) measurement for selectively quantifying cell surface markers expressed by neural stem cells and mature neurons. The variation of nestin antibodies concentrations from 9 μU to 27 μU showed a linear increase in DPV current with a detection sensitivity of ∼28 nA/μU of antibody. Varying concentrations of β-III tubulin antibodies from 30 μU to 210 μU showed a linear increase in DPV current with a detection sensitivity of ∼2.0 nA/μU of antibody. The highest expression level of cell surface marker corresponding to β-III tubulin in total adherent cells on ITO was calculated. It was in the order of 10-8 U of antibodies/cell, representing the total population of mature neuron cells. This new way of detection may rapidly assess the quantitative expression of cell surface markers/antigens.
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Affiliation(s)
- Juhi Jaiswal
- Nano-Cellular Medicine and Biophysics Laboratory, School of Biomedical Engineering, Indian Institute of Technology (BHU), Varanasi, 221005, Uttar Pradesh, India
| | - Marshal Dhayal
- Nano-Cellular Medicine and Biophysics Laboratory, School of Biomedical Engineering, Indian Institute of Technology (BHU), Varanasi, 221005, Uttar Pradesh, India.
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16
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Rippe K, Papantonis A. Functional organization of RNA polymerase II in nuclear subcompartments. Curr Opin Cell Biol 2022; 74:88-96. [PMID: 35217398 DOI: 10.1016/j.ceb.2022.01.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/08/2022] [Accepted: 01/14/2022] [Indexed: 12/22/2022]
Abstract
Distinct clusters of RNA polymerase II are responsible for gene transcription inside eukaryotic cell nuclei. Despite the functional implications of such subnuclear organization, the attributes of these clusters and the mechanisms underlying their formation remain only partially understood. Recently, the concept of proteins and RNA phase-separating into liquid-like droplets was proposed to drive the formation of transcriptionally-active subcompartments. Here, we attempt to reconcile previous with more recent findings, and discuss how the different ways of assembling the active RNA polymerase II transcriptional machinery relate to nuclear compartmentalization.
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Affiliation(s)
- Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany.
| | - Argyris Papantonis
- Translational Epigenetics Group, Institute of Pathology, University Medical Center Göttingen, Göttingen, Germany.
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17
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Tran VN, Shams A, Ascioglu S, Martinecz A, Liang J, Clarelli F, Mostowy R, Cohen T, Abel Zur Wiesch P. vCOMBAT: a novel tool to create and visualize a computational model of bacterial antibiotic target-binding. BMC Bioinformatics 2022; 23:22. [PMID: 34991453 DOI: 10.1186/s12859-021-04536-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 12/14/2021] [Indexed: 11/16/2022] Open
Abstract
Background As antibiotic resistance creates a significant global health threat, we need not only to accelerate the development of novel antibiotics but also to develop better treatment strategies using existing drugs to improve their efficacy and prevent the selection of further resistance. We require new tools to rationally design dosing regimens from data collected in early phases of antibiotic and dosing development. Mathematical models such as mechanistic pharmacodynamic drug-target binding explain mechanistic details of how the given drug concentration affects its targeted bacteria. However, there are no available tools in the literature that allow non-quantitative scientists to develop computational models to simulate antibiotic-target binding and its effects on bacteria. Results In this work, we have devised an extension of a mechanistic binding-kinetic model to incorporate clinical drug concentration data. Based on the extended model, we develop a novel and interactive web-based tool that allows non-quantitative scientists to create and visualize their own computational models of bacterial antibiotic target-binding based on their considered drugs and bacteria. We also demonstrate how Rifampicin affects bacterial populations of Tuberculosis bacteria using our vCOMBAT tool. Conclusions The vCOMBAT online tool is publicly available at https://combat-bacteria.org/. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04536-3.
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18
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Abstract
Drug-target residence time, the duration of binding at a given protein target, has been shown in some protein families to be more significant for conferring efficacy than binding affinity. To carry out efficient optimization of residence time in drug discovery, machine learning models that can predict that value need to be developed. One of the main challenges with predicting residence time is the paucity of data. This chapter outlines all of the currently available ligand kinetic data, providing a repository that contains the largest publicly available source of GPCR-ligand kinetic data to date. To help decipher the features of kinetic data that might be beneficial to include in computational models for the prediction of residence time, the experimental evidence for properties that influence residence time are summarized. Finally, two different workflows for predicting residence time with machine learning are outlined. The first is a single-target model trained on ligand features; the second is a multi-target model trained on features generated from molecular dynamics simulations.
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Affiliation(s)
- Andrew Potterton
- Structural and Molecular Biology, University College London, London, UK
- Evotec (U.K.) Ltd., Abingdon, Oxfordshire, UK
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19
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Erbaş A, Inci F. The Role of Ligand Rebinding and Facilitated Dissociation on the Characterization of Dissociation Rates by Surface Plasmon Resonance (SPR) and Benchmarking Performance Metrics. Methods Mol Biol 2022; 2385:237-253. [PMID: 34888723 DOI: 10.1007/978-1-0716-1767-0_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Surface plasmon resonance (SPR) is a real-time kinetic measurement principle that can probe the kinetic interactions between ligands and their binding sites, and lies at the backbone of pharmaceutical, biosensing, and biomolecular research. The extraction of dissociation rates from SPR-response signals often relies on several commonly adopted assumptions, one of which is the exponential decay of the dissociation part of the response signal. However, certain conditions, such as high density of binding sites or high concentration fluctuations near the surface as compared to the bulk, can lead to non-exponential decays via ligand rebinding or facilitated dissociation. Consequently, fitting the data with an exponential function can underestimate or overestimate the measured dissociation rates. Here, we describe a set of alternative fit functions that can take such effects into consideration along with plasmonic sensor design principles with key performance metrics, thereby suggesting methods for error-free high-precision extraction of the dissociation rates.
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Affiliation(s)
- Aykut Erbaş
- UNAM-National Nanotechnology Research Center and Institute of Materials Science Nanotechnology, Bilkent University, Ankara, Turkey.
| | - Fatih Inci
- UNAM-National Nanotechnology Research Center and Institute of Materials Science Nanotechnology, Bilkent University, Ankara, Turkey.
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20
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Wang S, Ma G, Liang R, Tao N. Charge Sensitive Optical Detection for Measurement of Small-Molecule Binding Kinetics. Methods Mol Biol 2022; 2393:315-328. [PMID: 34837187 DOI: 10.1007/978-1-0716-1803-5_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Charge sensitive optical detection (CSOD) technique is a label-free method for real-time measurement of molecular interactions. Traditional label-free optical detection techniques mostly measure the mass of a molecule, and they are less sensitive to small molecules. In contrast, CSOD detects the charge of a molecule, where the signal does not diminish with the size of the molecule, thus capable for studying small molecules. In addition, CSOD is compatible with the standard microplate platform, making it suitable for high-throughput screening of drug candidates. In CSOD, an optical fiber functionalized with the probe molecule is dipped into a well of a microplate where an alternate perpendicular electrical field is applied to the fiber, which drives the fiber into oscillation because of the presence of surface charge on the fiber. The binding of the target molecules changes the charge of the fiber, and thus the amplitude and phase of the oscillating fiber, which are precisely measured through tracking of the optical images of the fiber tip.
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Affiliation(s)
- Shaopeng Wang
- Biodesign Center for Bioelectronics and Biosensors, Arizona State University, Tempe, AZ, USA.
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA.
| | - Guangzhong Ma
- Biodesign Center for Bioelectronics and Biosensors, Arizona State University, Tempe, AZ, USA
| | - Runli Liang
- Biodesign Center for Bioelectronics and Biosensors, Arizona State University, Tempe, AZ, USA
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ, USA
| | - Nongjian Tao
- Biodesign Center for Bioelectronics and Biosensors, Arizona State University, Tempe, AZ, USA
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ, USA
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21
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de Vries E, Guo H, Du W, Liu M, van Kuppeveld FJM, de Haan CAM. Quantification of Receptor Association, Dissociation, and NA-Dependent Motility of Influenza A Particles by Biolayer Interferometry. Methods Mol Biol 2022; 2556:123-140. [PMID: 36175631 DOI: 10.1007/978-1-0716-2635-1_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
We describe a method for real-time analysis and quantification of influenza A virus (IAV)-receptor interactions by biolayer interferometry (BLI). Biotinylated synthetic sialoglycans or sialoglycoproteins (biotinylated or Fc-tagged) were immobilized on the tip of biosensors (coated with streptavidin or protein A) that were subsequently dipped into IAV particle solutions in 96-well plates. Association and/or dissociation of IAV particles was recorded in consecutive steps in buffers of choice. From the association and dissociation curves, parameters can be derived that describe IAV particle-receptor interactions in absence or presence of neuraminidase activity. Overall, the method provides a quantitative description of the hemagglutinin-neuraminidase balance that determines the interaction kinetics of IAV with specific sialoglycan receptors.
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Affiliation(s)
- Erik de Vries
- Section Virology, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
| | - Hongbo Guo
- Section Virology, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Jiangsu, People's Republic of China
| | - Wenjuan Du
- Section Virology, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Mengying Liu
- Section Virology, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Frank J M van Kuppeveld
- Section Virology, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Cornelis A M de Haan
- Section Virology, Division Infectious Diseases & Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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22
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Redhair M, Atkins WM. Analytical and functional aspects of protein-ligand interactions: Beyond induced fit and conformational selection. Arch Biochem Biophys 2021; 714:109064. [PMID: 34715072 DOI: 10.1016/j.abb.2021.109064] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/18/2021] [Accepted: 10/20/2021] [Indexed: 10/20/2022]
Abstract
Ligand-dependent changes in protein conformation are foundational to biology. Historical mechanistic models for substrate-specific proteins are induced fit (IF) and conformational selection (CS), which invoke a change in protein conformation after ligand binds or before ligand binds, respectively. These mechanisms have important, but rarely discussed, functional relevance because IF vs. CS can differentially affect a protein's substrate specificity or promiscuity, and its regulatory properties. The modern view of proteins as conformational ensembles in both ligand free and bound states, together with the realization that most proteins exhibit some substrate promiscuity, demands a deeper interpretation of the historical models and provides an opportunity to improve mechanistic analyses. Here we describe alternative analytical strategies for distinguishing the historical models, including the more complex expanded versions of IF and CS. Functional implications of the different models are described. We provide an alternative perspective based on protein ensembles interacting with ligand ensembles that clarifies how a single protein can 'apparently' exploit different mechanisms for different ligands. Mechanistic information about protein ensembles can be optimized when they are probed with multiple ligands.
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Affiliation(s)
- Michelle Redhair
- Department of Medicinal Chemistry, Box 375610, University of Washington, Seattle, WA, 98177, USA
| | - William M Atkins
- Department of Medicinal Chemistry, Box 375610, University of Washington, Seattle, WA, 98177, USA.
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23
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Conrad M, Fechner P, Proll G, Gauglitz G. Comparison of methods for quantitative biomolecular interaction analysis. Anal Bioanal Chem 2021; 414:661-673. [PMID: 34505164 PMCID: PMC8748344 DOI: 10.1007/s00216-021-03623-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/11/2021] [Accepted: 08/16/2021] [Indexed: 11/24/2022]
Abstract
In order to perform good kinetic experiments, not only the experimental conditions have to be optimized, but the evaluation procedure as well. The focus of this work is the in-depth comparison of different approaches and algorithms to determine kinetic rate constants for biomolecular interaction analysis (BIA). The different algorithms are applied not only to flawless simulated data, but also to real-world measurements. We compare five mathematical approaches for the evaluation of binding curves following pseudo-first-order kinetics with different noise levels. In addition, reflectometric interference spectroscopy (RIfS) measurements of two antibodies are evaluated to determine their binding kinetics. The advantages and disadvantages of the individual approach will be investigated and discussed in detail. In summary, we will raise awareness on how to evaluate and judge results from BIA by using different approaches rather than having to rely on “black box” closed (commercial) software packages.
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Affiliation(s)
- Monika Conrad
- Institute of Physical and Theoretical Chemistry (IPTC), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.
| | - Peter Fechner
- Institute of Physical and Theoretical Chemistry (IPTC), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Günther Proll
- Institute of Physical and Theoretical Chemistry (IPTC), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Günter Gauglitz
- Institute of Physical and Theoretical Chemistry (IPTC), Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
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24
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Orthwein T, Huergo LF, Forchhammer K, Selim KA. Kinetic Analysis of a Protein-protein Complex to Determine its Dissociation Constant (K D) and the Effective Concentration (EC 50) of an Interplaying Effector Molecule Using Bio-layer Interferometry. Bio Protoc 2021; 11:e4152. [PMID: 34604457 DOI: 10.21769/bioprotoc.4152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 06/07/2021] [Accepted: 06/21/2021] [Indexed: 11/02/2022] Open
Abstract
Biolayer interferometry (BLI) is an emerging analytical tool that allows the study of protein complexes in real time to determine protein complex kinetic parameters. This article describes a protocol to determine the KD of a protein complex using a 6×His tagged fusion protein as bait immobilized on the NTA sensor chip of the FortéBio® Octet K2 System (Sartorius). We also describe how to determine the half maximal effective concentration (EC50, also known as IC50 for inhibiting effectors) of a metabolite. The complete protocol allows the determination of protein complex KD and small molecular effector EC50 within 8 h, measured in triplicates. Graphic abstract: Principle of the Biolayer interferometry measurement. (Middle, top) Exemplary result of the BLI measurement using Octet® (Raw Data). Wavelength shift (Δλ) against time. (A) Baseline 1. Baseline measurement. When the sensor is equilibrated in the kinetics buffer. The light is reflected with no difference. (B) Load. The his-tagged proteins (ligand) are loaded onto the sensor surface. The light is reflected with a shift of the wavelength. (C) Baseline 2. The loaded sensor is equilibrated in the kinetics buffer. No further wavelength shift appears. (D) Association. The loaded sensor is dipped into the analyte solution. The analyte binds to the immobilized ligand along with an increased wavelength shift. (E) Dissociation. Afterward, the sensor is dipped again into the kinetics buffer without the analyte. Some analyte molecules dissociate. The wavelength shift decreases. (Subfigures A-E) The left side shows the position of the sensor during the measurement seen in the representative BLI measurement, marked with the figure label. The right side shows the light path in the sensor. Black waves represent the light emitted to the sensor surface. The red waves show the light reflected from the sensor surface back to the detector.
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Affiliation(s)
- Tim Orthwein
- Organismic Interactions Department, Interfaculty Institute for Microbiology and Infection Medicine, Cluster of Excellence 'Controlling Microbes to Fight Infections', Tübingen University, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Luciano F Huergo
- Setor Litoral, Federal University of Paraná (UFPR), Matinhos, Brazil
| | - Karl Forchhammer
- Organismic Interactions Department, Interfaculty Institute for Microbiology and Infection Medicine, Cluster of Excellence 'Controlling Microbes to Fight Infections', Tübingen University, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Khaled A Selim
- Organismic Interactions Department, Interfaculty Institute for Microbiology and Infection Medicine, Cluster of Excellence 'Controlling Microbes to Fight Infections', Tübingen University, Auf der Morgenstelle 28, 72076 Tübingen, Germany.,Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, Germany.,Pharmaceutical and Drug Industries Research Division, National Research Center, Giza, Egypt
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25
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Wang J, Giragossian C, Hansel S. Analyze impact of tumor-associated kinetics on antibody delivery in solid tumors with a physiologically based pharmacokinetics/pharmacodynamics model. Eur J Pharm Biopharm 2021; 168:110-121. [PMID: 34478854 DOI: 10.1016/j.ejpb.2021.08.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 08/23/2021] [Accepted: 08/27/2021] [Indexed: 11/17/2022]
Abstract
Monoclonal antibody (mAb)-based drugs are critical anti-cancer therapies. Unfortunately, therapeutic efficacy can be compromised by spatially heterogeneous intratumoral Ab deposition. Binding-site barriers arising from Ab and tumor-associated kinetics often underlie this phenomenon. Quantitative insight into these issues may lead to more efficient drug delivery. Difficulties in addressing this issue include (1) lack of techniques to quantify critical kinetic events, (2) lack of a pharmacokinetic/pharmacodynamic (PK/PD) model to assess important parameters for specific tumor types, and (3) uncertainty or variability of critical kinetic factors even within a single tumor type. This study developed a mechanism-based PK/PD model to profile heterogeneous distribution of Ab within tumors and tested this model using real-life experimental data. Model simulations incorporating several uncertainties were used to determine how mAb and tumor-associated kinetics influence receptor occupancy. Simulations were also used to predict the potential impact of these findings in preclinical tumor models and human tumors. We found significant differences in tumor-associated kinetics between groups in which mAb therapy was effective versus groups in which it was ineffective. These kinetic differences included rates of tumor-associated antigen (TAA) degradation, TAA expression, apparent flow rates of interstitial fluid, and ratios of Ab-TAA complex internalization to TAA degradation. We found less significant differences in mAb kinetics, including rates of clearance or affinity for target antigens. In conclusion, our mechanism-based PK/PD model suggests that TAA-associated kinetic factors participate more significantly than those associated with the Ab in generating barriers to mAb delivery and distribution in tumors.
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Affiliation(s)
- Jun Wang
- Biotherapeutics Discovery Research, Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA.
| | - Craig Giragossian
- Biotherapeutics Discovery Research, Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
| | - Steven Hansel
- Biotherapeutics Discovery Research, Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
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26
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Zhou Y, Cao W, Xu Z, Zhang XF, Liu Y. Binding kinetics of liposome conjugated E-selectin and P-selectin glycoprotein ligand-1 measured with atomic force microscopy. Colloids Surf B Biointerfaces 2021; 207:112002. [PMID: 34343911 DOI: 10.1016/j.colsurfb.2021.112002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 06/28/2021] [Accepted: 07/22/2021] [Indexed: 11/21/2022]
Abstract
Various ligand-functionalized liposomes have been developed for targeted therapies. Typically, the binding properties of the ligands and targeted proteins are measured with surface plasmon resonance (SPR), where the proteins are immobilized on a rigid surface. However, the difference of protein-ligand binding kinetics between liposome-conjugated protein and rigid surface-conjugated protein is not fully understood. In this work, the binding kinetics of P-selectin glycoprotein ligand-1 (PSGL-1) and E-selectin conjugated on liposome and on rigid surfaces are investigated with Atomic Force Microscopy (AFM). The results suggest that protein orientation and diffusion on liposomal membrane can alter the binding kinetics of the protein-ligand interaction. Specifically, the association and dissociation rate constant of AFM probe-conjugated E-selectin and glass-conjugated PSGL-1 are measured as 9.32 × 104 M-1s-1 and 1.54 s-1, respectively. While for the liposome-conjugated E-selectin and glass-conjugated PSGL-1, the kinetic constants are measured as 5.00 × 107 M-1s-1 and 2.76 s-1, respectively. Thus, there is an order's magnitude increase of binding affinity (from kd = 16.51 μM to kd = 0.06 μM) when protein is attached to liposome compared to attached to a rigid surface. The results might provide better understanding and pave the way for the future design of the ligand-targeted liposomes.
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27
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Spiegelberg D, Stenberg J, Richalet P, Vanhove M. K D determination from time-resolved experiments on live cells with LigandTracer and reconciliation with end-point flow cytometry measurements. Eur Biophys J 2021; 50:979-991. [PMID: 34302187 PMCID: PMC8448686 DOI: 10.1007/s00249-021-01560-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 06/16/2021] [Accepted: 07/01/2021] [Indexed: 11/30/2022]
Abstract
Design of next-generation therapeutics comes with new challenges and emulates technology and methods to meet them. Characterizing the binding of either natural ligands or therapeutic proteins to cell-surface receptors, for which relevant recombinant versions may not exist, represents one of these challenges. Here we report the characterization of the interaction of five different antibody therapeutics (Trastuzumab, Rituximab, Panitumumab, Pertuzumab, and Cetuximab) with their cognate target receptors using LigandTracer. The method offers the advantage of being performed on live cells, alleviating the need for a recombinant source of the receptor. Furthermore, time-resolved measurements, in addition to allowing the determination of the affinity of the studied drug to its target, give access to the binding kinetics thereby providing a full characterization of the system. In this study, we also compared time-resolved LigandTracer data with end-point KD determination from flow cytometry experiments and hypothesize that discrepancies between these two approaches, when they exist, generally come from flow cytometry titration curves being acquired prior to full equilibration of the system. Our data, however, show that knowledge of the kinetics of the interaction allows to reconcile the data obtained by flow cytometry and LigandTracer and demonstrate the complementarity of these two methods.
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Affiliation(s)
- Diana Spiegelberg
- Department of Surgical Sciences, Uppsala University, 751 85, Uppsala, Sweden
| | - Jonas Stenberg
- Ridgeview Instruments AB, Skillsta 4, 740 20, Vänge, Sweden.,A3P Biomedical AB, Vallongatan 1, 752 28, Uppsala, Sweden
| | | | - Marc Vanhove
- Marc Vanhove Consultancy, 4100, Boncelles, Belgium. .,Oxurion N.V., Gaston Geenslaan 1, 3001, Leuven, Belgium.
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28
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Yang H, Li X, Li G, Huang H, Yang W, Jiang X, Sen M, Liu J, Liu Y, Pan Y, Wang G. Accurate quantitative determination of affinity and binding kinetics for tight binding inhibition of xanthine oxidase. Biomed Pharmacother 2021; 139:111664. [PMID: 34243606 DOI: 10.1016/j.biopha.2021.111664] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 11/28/2022] Open
Abstract
The accurate quantitative determination of affinity and binding kinetics (BK) for tight binding inhibition is extraordinary important from both the continuous optimization of compounds, particularly in developing structure-activity relationships (SAR), and the prediction of in vivo target occupancy (TO). Due to the unique properties for tight binding inhibition that the inhibitors are characterized by the ultrahigh-affinity, relatively fast association to the target enzyme combined with extremely slow dissociation of the inhibitor-enzyme binary complex, the classical steady state equilibrium methods are no longer valid. Here, we made several recommendations of how to design the optimal experiments and apply special mathematical calculation approaches to quantitatively evaluate the accurate affinity and BK as the examples of two tight binding inhibitors against the xanthine oxidase (XO), as well as compared the differences in the results calculated from the different data analytical methods and analyzed the influence of these differences on the XO engagement in human. Analysis of the results displayed that the accurate apparent dissociation constant (Ki*,app) was 0.2 ± 0.06 nM for topiroxotstat and was 0.45 ± 0.2 nM for febuxostat; that on-rate (kon) was (4.3 ± 1.1) × 106 M-1s-1 for topiroxotstat and was(133.3 ± 3.5) × 106 M-1s-1 for febuxostat, and off-rate (koff) was (1.0±0.2) × 10-5 s-1 for topiroxotstat and was ≤ 0.16 × 10-5 s-1for febuxostat. Moreover, there were significant differences in the Ki*,app and koff values estimated using the appropriate specialized methods for tight binding inhibition versus classical steady state equilibrium methods, with the substantial differences of 14-fold and 32-fold reduction for topiroxostat, respectively, and of 9.6-fold and ≥ 213-fold reduction for febuxostat, while the kon values remain the moderate differences for the two inhibitors. The obvious greater AUC of XO engagement time courses and longer durations of above 70% engagement by the appropriate specialized methods for tight binding inhibition were observed that the results display the differences of 70.1% and 88%, respectively for topiroxostat and of 38.1% and 35.0%, respectively for febuxostat in human liver cell than by classical steady state equilibrium methods. Again, our studies provide several valuable recommendations of the optimal experiment protocols and appropriate analytical approaches for accurately quantitatively assessing the affinity and BK parameters as well as demonstrate the ability of our recommended methods to generate reliable data for tight binding inhibitors against XO.
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Affiliation(s)
- Haiyang Yang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Xueyan Li
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Gang Li
- Beijing Adamadle Biotech Co., Ltd., Beijing 100102, China
| | - Huating Huang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Wenning Yang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Xiaoquan Jiang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Muli Sen
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China
| | - Jingjing Liu
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Yang Liu
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China.
| | - Yanli Pan
- Institute of Information on Traditional Chinese Medicine China Academy of Chinese Medical Sciences, Beijing 100700, China.
| | - Guopeng Wang
- Zhongcai Health (Beijing) Biological Technology Development Co., Ltd., Beijing 101500, China.
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Cheng L, Song S, Zhou B, Ge X, Yu J, Zhang M, Ju B, Zhang Z. Impact of the N501Y substitution of SARS-CoV-2 Spike on neutralizing monoclonal antibodies targeting diverse epitopes. Virol J 2021; 18:87. [PMID: 33910569 PMCID: PMC8081001 DOI: 10.1186/s12985-021-01554-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 04/14/2021] [Indexed: 12/20/2022] Open
Abstract
The emergence and rapid spread of the B.1.1.7 lineage (VOC-202012/01) SARS-CoV-2 variant has aroused global concern. The N501Y substitution is the only mutation in the interface between the RBD of B.1.1.7 and ACE2, raising concerns that its recognition by neutralizing antibodies may be affected. Here, we assessed the neutralizing activity and binding affinity of a panel of 12 monoclonal antibodies against the wild type and N501Y mutant SARS-CoV-2 pseudovirus and RBD protein, respectively. We found that the neutralization activity and binding affinity of most detected antibodies (10 out of 12) were unaffected, although the N501Y substitution decreased the neutralizing and binding activities of CB6 and increased that of BD-23. These findings could be of value in the development of therapeutic antibodies.
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Affiliation(s)
- Lin Cheng
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China
| | - Shuo Song
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China
| | - Bing Zhou
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China
| | - Xiangyang Ge
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China
| | - Jiazhen Yu
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China
| | - Mingxia Zhang
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China
| | - Bin Ju
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China.
- Shenzhen Research Center for Communicable Disease Diagnosis and Treatment of Chinese Academy of Medical Science, Shenzhen, 518112, Guangdong Province, China.
- Guangdong Key Laboratory for Anti-Infection Drug Quality Evaluation, Shenzhen, 518112, Guangdong Province, China.
- Shenzhen Bay Laboratory, Shenzhen, 518055, Guangdong Province, China.
| | - Zheng Zhang
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital; The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, Shenzhen, 518112, Guangdong Province, China.
- Shenzhen Research Center for Communicable Disease Diagnosis and Treatment of Chinese Academy of Medical Science, Shenzhen, 518112, Guangdong Province, China.
- Guangdong Key Laboratory for Anti-Infection Drug Quality Evaluation, Shenzhen, 518112, Guangdong Province, China.
- Shenzhen Bay Laboratory, Shenzhen, 518055, Guangdong Province, China.
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30
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Ma G, Wan Z, Wang S. Simultaneous Imaging of Single Protein Size, Charge, and Binding Using A Protein Oscillation Approach. Bio Protoc 2021; 11:e3934. [PMID: 33796608 DOI: 10.21769/bioprotoc.3934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/27/2020] [Accepted: 01/05/2021] [Indexed: 11/02/2022] Open
Abstract
Electrophoresis and Western blot are important tools in protein research for detection and identification of proteins. These traditional techniques separate the proteins based on size and charge differences and identify the proteins by antibody binding. Over the past decade, the emergence of single-molecule techniques has shown great potential in improving the resolution of the traditional protein analysis methods to the single-molecule level. However, such single-molecule techniques measure either size or charge, and it is challenging to measure both at the same time. Recently, we have developed a single-molecule approach to address this problem. We tether the single proteins to a surface with a polymer linker and drive them into oscillation with an electric field. By tracking the electromechanical response of the proteins to the field using an optical imaging method, the size and charge can be obtained simultaneously. Binding of antibodies or ions to the tethered protein also changes the size and charge, which allows us to probe the interactions. This protocol includes fabrication of protein oscillators, configuration of the optical detection system, and analysis of the oscillation signal for quantification of protein size and charge. We wish this protocol will enable researchers to perform comprehensive single-protein analysis on a single platform.
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Affiliation(s)
- Guangzhong Ma
- Biodesign Center for Biosensors and Bioelectronics, Arizona State University, Tempe, USA
| | - Zijian Wan
- Biodesign Center for Biosensors and Bioelectronics, Arizona State University, Tempe, USA.,School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, USA
| | - Shaopeng Wang
- Biodesign Center for Biosensors and Bioelectronics, Arizona State University, Tempe, USA
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31
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Bhagwat A, Zhang F, Collins CH, Dordick JS. Influence of bacterial culture medium on peptidoglycan binding of cell wall lytic enzymes. J Biotechnol 2021; 330:27-34. [PMID: 33652073 DOI: 10.1016/j.jbiotec.2021.02.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 02/18/2021] [Indexed: 10/22/2022]
Abstract
The bacteriolysin lysostaphin (Lst) and endolysin PlyPH are potent modular lytic enzymes with activity against clinically-relevant Gram-positive Staphylococcus aureus and Bacillus cereus, respectively. Both enzymes possess an N-terminal catalytic domain and C-terminal binding domain, with the latter conferring significant enzyme specificity. Lst and PlyPH show reduced activity in the presence of bacterial growth-supporting conditions, such as complex media. Here, we hypothesize that Lst and PlyPH bind poorly to their targets in growth media, which may influence their use in antimicrobial applications in the food industry, as therapeutics, and for control of microbial communities. To this end, binding of isolated Lst and PlyPH binding domains to target bacteria was quantified in the presence of three increasingly complex media - phosphate buffered saline (PBS), defined growth medium (AAM) and undefined complex medium (TSB) by surface plasmon resonance (SPR) and flow cytometry. Evaluation of binding kinetics by SPR demonstrated that PlyPH binding was particularly sensitive to medium composition, with 8-fold lower association and 3.4-fold lower dissociation rate constants to B. cereus in TSB compared to PBS. Flow cytometry studies indicated a decrease in the binding-dependent fluorescent populations of S. aureus and B. cereus, for lysostaphin binding domain and PlyPH binding domain, respectively, in TSB compared to PBS. Enzyme binding behavior was consistent with the enzymes' catalytic activity in the three media, thereby suggesting that compromised enzyme binding could be responsible for poor activity in more complex growth media.
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Affiliation(s)
- Amala Bhagwat
- Department of Chemical and Biological Engineering, and Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, United States
| | - Fuming Zhang
- Department of Chemical and Biological Engineering, and Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, United States
| | - Cynthia H Collins
- Department of Chemical and Biological Engineering, and Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, United States.
| | - Jonathan S Dordick
- Department of Chemical and Biological Engineering, and Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, United States.
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32
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Abstract
Surface Plasmon Resonance (SPR) is a powerful biophysical method for characterizing small molecule binding to proteins. Owing to its ability to characterize binary inteactions between warheads and E3 ligases or substrates, SPR is a useful tool for the development of targeted protein degraders. SPR is also an effective method for optimizing linkers and characterizing ternary complex interactions that are mediated by heterobifunctional ligands (Roy et al. ACS Chem Biol 14:361-368, 2019). Recent advances in the throughput of modern instruments have improved the ability of SPR to rapidly triage ligands based on binding kinetics and affinity, making this technique invaluable for driving degrader optimization. This chapter describes the characterization of ligands binding to the Thalidomide Binding Domain of mouse Cereblon (mCRBN-TBD) using the Biacore 8K+.
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33
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Abstract
Calorimetry is a classical biophysical method that by definition measures heat. In isothermal titration calorimetry (ITC), the heat is the result of titrating interacting components together and allows direct determination of the thermodynamics for this process. The measured heat reflects the enthalpy change (ΔH), and the prospect of determining this in biological systems where high-resolution structural information is available has led to the possibility of rational thermodynamics-guided design of ligands. Although there are limitations to this approach due to the participation of solvent in the thermodynamics, ITC has become an established technique in many labs providing a valuable tool with which to quantify protein-protein interactions. With careful use, ITC can also provide additional insights into the binding process or be used in increasingly complex systems and where interaction is coupled to other molecular events.
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34
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Abstract
An understanding of the kinetic contributions to G protein-coupled receptor pharmacology and signaling is increasingly important in compound profiling. Nonequilibrium conditions are commonly present in vivo, for example, as the drug competes with dynamic changes in hormone or neurotransmitter concentration for the receptor. Under such conditions individual binding kinetic properties of the ligands can influence duration of action, local ligand concentration, and functional properties such as the degree of insurmountable inhibition. Mapping the kinetic patterns of GPCR signaling events elicited by agonists, rather than a peak response at a single timepoint, is often key to predicting their functional impact. This is also a path to a better understanding of the origins of ligand bias, and whether such ligands demonstrate their effects through selection of distinct GPCR conformations, or via their kinetic properties. Recent developments in complementation approaches, based on a small bright shrimp luciferase Nanoluc, provide a new route to kinetic analysis of GPCR signaling in living cells that is amenable to the throughput required for compound profiling. In the NanoBiT luciferase complementation system, GPCRs and effector proteins are tagged with Nanoluc fragments optimized for their low interacting affinity and stability. The interactions brought about by GPCR recruitment of the effector are reproduced by a rapid and reversible increase in NanoBiT luminescence, in the presence of its substrate furimazine. Here we discuss the methods for optimizing and validating the GPCR NanoBiT assays, and protocols for their application to study endpoint and kinetic aspects of agonist and antagonist pharmacology. We also describe how timecourse families of agonist concentration response curves, derived from a single NanoBiT assay experiment, can be used to evaluate the kinetic components in operational model derived parameters of ligand bias.
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Affiliation(s)
- Nicola C Dijon
- School of Life Sciences, The Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Nottingham, UK
| | - Desislava N Nesheva
- School of Life Sciences, The Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Nottingham, UK
| | - Nicholas D Holliday
- School of Life Sciences, The Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, UK. .,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, Nottingham, UK. .,Excellerate Bioscience, Biocity, Nottingham, UK.
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35
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Veiksina S, Tahk MJ, Laasfeld T, Link R, Kopanchuk S, Rinken A. Fluorescence Anisotropy-Based Assay for Characterization of Ligand Binding Dynamics to GPCRs: The Case of Cy3B-Labeled Ligands Binding to MC 4 Receptors in Budded Baculoviruses. Methods Mol Biol 2021; 2268:119-136. [PMID: 34085265 DOI: 10.1007/978-1-0716-1221-7_8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During the past decade, fluorescence methods have become valuable tools for characterizing ligand binding to G protein-coupled receptors (GPCRs). However, only a few of the assays enable studying wild-type receptors and monitor the ligand binding in real time. One of the approaches that is inherently suitable for this purpose is the fluorescence anisotropy (FA) assay. In the FA assay, the change of ligand's rotational freedom connected with its binding to the receptor can be monitored with a conventional fluorescence plate reader equipped with suitable optical filters. To achieve the high receptor concentration required for the assay and the low autofluorescence levels essential for reliable results, budded baculoviruses that display GPCRs on their surfaces can be used. The monitoring process generates a substantial amount of kinetic data, which is usually stored as a proprietary file format limiting the flexibility of data analysis. To solve this problem, we propose the use of the data curation software Aparecium ( http://gpcr.ut.ee/aparecium.html ), which integrates experimental data with metadata in a Minimum Information for Data Analysis in Systems Biology (MIDAS) format. Aparecium enables data export to different software packages for fitting to suitable kinetic or equilibrium models. A combination of the FA assay with the novel data analysis strategy is suitable for screening new active compounds, but also for modeling complex systems of ligand binding to GPCRs. We present the proposed approach using different fluorescent probes and assay types to characterize ligand binding to melanocortin 4 (MC4) receptor.
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Affiliation(s)
- Santa Veiksina
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | | | - Tõnis Laasfeld
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | - Reet Link
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | | | - Ago Rinken
- Institute of Chemistry, University of Tartu, Tartu, Estonia.
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36
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Toto A, Troilo F, Malagrinò F, Gianni S. Understanding Binding-Induced Folding by Temperature Jump. Methods Mol Biol 2020; 2141:651-661. [PMID: 32696382 DOI: 10.1007/978-1-0716-0524-0_33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Temperature jump is a powerful technique for the characterization of fast kinetics and can be readily employed to understand both binding and folding reactions. Here we summarize briefly a temperature-jump prototypical experiment between an intrinsically disordered protein and its physiological partner. The model used is the NTAIL domain from Measles virus Nucleoprotein and its natural ligand, the globular PXD domain from Measles virus Phosphoprotein. We recapitulate how to set up the experiment and how to analyze data in order to extract the kinetic parameters of the reaction.
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Affiliation(s)
- Angelo Toto
- Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Rome, Italy
| | - Francesca Troilo
- Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Rome, Italy
| | - Francesca Malagrinò
- Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Rome, Italy
| | - Stefano Gianni
- Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Rome, Italy.
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37
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Liu C, Xia L, Fu K, Cao X, Yan W, Cheng J, Roux T, Peletier LA, Yin X, Guo D. Revisit ligand-receptor interaction at the human vasopressin V 2 receptor: A kinetic perspective. Eur J Pharmacol 2020; 880:173157. [PMID: 32360346 DOI: 10.1016/j.ejphar.2020.173157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 03/07/2020] [Accepted: 04/23/2020] [Indexed: 02/07/2023]
Abstract
The vasopressin V2 receptor belongs to the superfamily of G protein-coupled receptors (GPCRs) and is a potential drug target for water balance disorders such as polycystic kidney disease. Traditionally, the discovery of novel agents for the vasopressin V2 receptor has been guided by evaluating their receptor affinity, largely ignoring the binding kinetics. However, the latter is receiving increasing attention in the drug research community and has been proved to be a more complete descriptor of the dynamic process of ligand-receptor interaction. Herein we aim to revisit the molecular basis of ligand-vasopressin V2 receptor interaction from the less-investigated kinetic perspective. A homogenous time-resolved fluorescence resonance energy transfer (TR-FRET) assay was set up and optimized, which enabled accurate kinetic profiling of unlabeled vasopressin V2 receptor ligands. Receptor occupancy profiles of two representative antagonists with distinct target residence time were simulated. Their functional effects were further explored in cAMP assays. Our results showed that the antagonist with longer receptor residence time (lixivaptan) displayed sustained target occupancy than the antagonist with shorter receptor residence time (mozavaptan). In accordance, lixivaptan displayed insurmountable antagonism and wash-resistant inhibitory effect on the cellular cAMP level, while not so for mozavaptan. Together, our data provide evidence that binding kinetics, next to their affinity, offers additional information for the dynamic process of ligand-receptor interaction. Hopefully, this study may lead to more kinetics-directed medicinal chemistry efforts and aid the design and discovery of different-in-class of vasopressin V2 receptor ligands for clinical applications.
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Affiliation(s)
- Chunji Liu
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China
| | - Leyi Xia
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China
| | - Kequan Fu
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China
| | - Xudong Cao
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China
| | - Wenzhong Yan
- iHuman Institute, ShanghaiTech University, Shanghai, 201210, China
| | - Jianjun Cheng
- iHuman Institute, ShanghaiTech University, Shanghai, 201210, China
| | - Thomas Roux
- Cisbio Bioassays, Parc Marcel Boiteux, BP 84175, 30200, Codolet, France
| | - Lambertus A Peletier
- Mathematical Institute, Leiden University, P.O. Box 9512, 2300, RA, Leiden, the Netherlands
| | - Xiaoxing Yin
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China.
| | - Dong Guo
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China.
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Clarelli F, Liang J, Martinecz A, Heiland I, Abel Zur Wiesch P. Multi-scale modeling of drug binding kinetics to predict drug efficacy. Cell Mol Life Sci 2020; 77:381-394. [PMID: 31768605 PMCID: PMC7010620 DOI: 10.1007/s00018-019-03376-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 11/06/2019] [Accepted: 11/12/2019] [Indexed: 01/18/2023]
Abstract
Optimizing drug therapies for any disease requires a solid understanding of pharmacokinetics (the drug concentration at a given time point in different body compartments) and pharmacodynamics (the effect a drug has at a given concentration). Mathematical models are frequently used to infer drug concentrations over time based on infrequent sampling and/or in inaccessible body compartments. Models are also used to translate drug action from in vitro to in vivo conditions or from animal models to human patients. Recently, mathematical models that incorporate drug-target binding and subsequent downstream responses have been shown to advance our understanding and increase predictive power of drug efficacy predictions. We here discuss current approaches of modeling drug binding kinetics that aim at improving model-based drug development in the future. This in turn might aid in reducing the large number of failed clinical trials.
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Affiliation(s)
- Fabrizio Clarelli
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, 9037, Tromsø, Norway
| | - Jingyi Liang
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, 9037, Tromsø, Norway
| | - Antal Martinecz
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, 9037, Tromsø, Norway
| | - Ines Heiland
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, 9037, Tromsø, Norway
| | - Pia Abel Zur Wiesch
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, 9037, Tromsø, Norway.
- Centre for Molecular Medicine Norway, Nordic EMBL Partnership, Blindern, P.O. Box 1137, 0318, Oslo, Norway.
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39
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Kamat V, Rafique A, Huang T, Olsen O, Olson W. The impact of different human IgG capture molecules on the kinetics analysis of antibody-antigen interaction. Anal Biochem 2020; 593:113580. [PMID: 31926892 DOI: 10.1016/j.ab.2020.113580] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 01/06/2020] [Indexed: 12/12/2022]
Abstract
Surface plasmon resonance (SPR) is a well-established method to characterize biomolecular interactions and is widely used in drug discovery and development. Here, we demonstrate that capture surfaces profoundly impact the binding kinetics parameters that are measured for antibody-antigen interactions. Six unique antibody-antigen interactions were characterized using eight different anti-human IgG capture surfaces. The antigen binding affinities for six different human monoclonal antibodies (hmAbs) captured using three different goat anti-human Fc (AHC) polyclonal antibody (pAb) surfaces were in reasonable agreement (3-7-fold weaker) with those measured by kinetic exclusion assay (KinExA). In contrast, up to 81, 32, 489, 2826, and 219-fold weaker antigen binding affinities were measured using mouse AHC mAb, Protein G, Protein A, Protein A/G, and Protein L surfaces, respectively. Protein A, Protein A/G and Protein G interacted with the Fab of hmAbs, possibly affecting antigen binding to hmAbs captured over these surfaces. Additional studies revealed that mouse AHC mAb binds hmAbs with a weak affinity (5.5-36.3 nM) and t½ values of 1.4-3.3min, compared to the sub-nanomolar affinities of the goat AHC pAbs. These results emphasize the value of measuring binding kinetics of the capture molecule before immobilizing them onto the sensor surface to perform capture kinetics assays on label-free biosensors.
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Affiliation(s)
- Vishal Kamat
- Biomolecular HTS Center, Therapeutic Proteins, Regeneron Pharmaceuticals, Tarrytown, NY, USA.
| | - Ashique Rafique
- Biomolecular HTS Center, Therapeutic Proteins, Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | - Tammy Huang
- Therapeutic Proteins, Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | - Olav Olsen
- Therapeutic Proteins, Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | - William Olson
- Therapeutic Proteins, Regeneron Pharmaceuticals, Tarrytown, NY, USA
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40
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Chiodi E, Sola L, Brambilla D, Cretich M, Marn AM, Ünlü MS, Chiari M. Simultaneous evaluation of multiple microarray surface chemistries through real-time interferometric imaging. Anal Bioanal Chem 2020; 412:3477-87. [PMID: 31901959 DOI: 10.1007/s00216-019-02276-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/09/2019] [Accepted: 11/11/2019] [Indexed: 11/25/2022]
Abstract
Surface chemistry is a crucial aspect for microarray modality biosensor development. The immobilization capability of the functionalized surface is indeed a limiting factor for the final yield of the binding reaction. In this work, we were able to simultaneously compare the functionality of protein ligands that were locally immobilized on different polymers, while on the same solid support, therefore demonstrating a new way of multiplexing. Our goal was to investigate, in a single experiment, both the immobilization efficiency of a group of reactive polymers and the resulting affinity of the tethered molecules. This idea was demonstrated by spotting many reactive polymers on a Si/SiO2 chip and depositing the molecular probes on the spots immediately after. As a proof of concept, we focused on which polymers would better immobilize a model protein (α-Lactalbumin) and a peptide (LAC-1). We successfully showed that this protocol is applicable to proteins and peptides with a good efficiency. By means of real-time binding measurements performed with the interferometric reflectance imaging sensor (IRIS), local functionalization proved to be comparable to the classical flat coating solution. The final outcome highlights the multiplexing power of this method: first, it allows to characterize dozens of polymers at once. Secondly, it removes the limitation, related to coated surfaces, that only molecules with the same functional groups can be tethered to the same solid support. By applying this protocol, many types of molecules can be studied simultaneously and immobilization for each probe can be individually optimized.
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41
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Polyak SW, Mowla R, Venter H. Measuring Small Molecule Binding to Escherichia coli AcrB by Surface Plasmon Resonance. Methods Mol Biol 2020; 2089:119-30. [PMID: 31773650 DOI: 10.1007/978-1-0716-0163-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Antimicrobial resistance (AMR) is rapidly becoming one of the great healthcare challenges. A common mechanism employed by pathogenic bacteria to avoid the action of certain antibiotics is to overexpress efflux pumps that can extrude these drugs from the cell rendering them ineffective. Small molecule inhibitors that target bacterial efflux pumps provide a route toward reversing AMR. Here, we describe the application of surface plasmon resonance (SPR) technology to characterize protein:small molecule interactions between the inner membrane protein AcrB subunit of the Escherichia coli AcrA-AcrB-TolC efflux pump and its substrates and novel inhibitors. The SPR assay provides quantitative data about the kinetics of binding that can help guide the development of new chemotherapies to combat AMR.
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42
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Worms D, Maertens B, Kubicek J, Subhramanyam UKT, Labahn J. Expression, purification and stabilization of human serotonin transporter from E. coli. Protein Expr Purif 2019; 164:105479. [PMID: 31442583 DOI: 10.1016/j.pep.2019.105479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 07/31/2019] [Accepted: 08/15/2019] [Indexed: 11/21/2022]
Abstract
The serotonin transporter belongs to the family of sodium-chloride coupled neurotransmitter transporter and is related to depression in humans. It is therefore an important drug target to support treatment of depression. Recently, structures of human serotonin transporter in complex with inhibitor molecules have been published. However, the production of large protein amounts for crystallization experiments remains a bottleneck. Here we present the possibility to obtain purified serotonin transporter from E. coli. Fos-choline 12 solubilized target protein was obtained with a purity of >95% and a yield of 1.2 mg L-1 culture in autoinduction medium. CD spectroscopic analysis of protein stability allowed identifying CHS and POPX as stabilizing components, which increased hSERT thermostability by 7 °C. The kinetic dissociation constant KD of 2.8 μM (±0.05) for of the inhibitor Desipramine was determined with a ka of 10,848 M - 1 s-1 (±220) and a kd of 0.03 s-1 (±4.7 × 10-5).
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43
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Che H, Zhang H, Tian Y, Lai PFH, Xia Y, Wang S, Ai L. Exopolysaccharide from Streptococcus thermophilus as stabilizer in fermented dairy: Binding kinetics and interactions with casein of milk. Int J Biol Macromol 2019; 140:1018-1025. [PMID: 31437497 DOI: 10.1016/j.ijbiomac.2019.08.146] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 08/12/2019] [Accepted: 08/17/2019] [Indexed: 01/01/2023]
Abstract
Exopolysaccharides (EPSs) from lactic acid bacteria have great effect on the quality of fermented milk products. However, the mechanism for the quality improvement has not been well described. This study aimed to investigate the molecular binding kinetics and interactions between EPS obtained from Streptococcus thermophilus AR333 (EPS333) and casein of milk (CM) in a simulated acidifying process. The results indicated that EPS333 had a significant effect on the stability of casein micelles at acidic pH (6.0-4.5) according to the turbidity, ζ-potential, particle size and distribution analysis. The adsorption-desorption study by bio-layer interferometry identified the direct affinity binding between EPS333 and CM, the interactive moiety of casein was α-casein, rather than β- or κ-casein. Fluorescence quenching analysis revealed that the force types of interaction between EPS333 and CM were dynamically changeable during the acidifying process, mainly from electrostatic interaction at pH 7.0-6.5, to hydrophobic or hydrogen bonding at pH 6.5-5.5, and then transferred to electrostatic interaction again at pH 5.5-5.0. Conclusively, EPS333 could bind with CM directly via different binding forces during acidifying process to stabilize the properties of casein micelles.
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Affiliation(s)
- Haoqi Che
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instruments and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Hui Zhang
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instruments and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Yanjun Tian
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250013, China
| | - Phoency F H Lai
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instruments and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Yongjun Xia
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instruments and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Shijie Wang
- Shijiazhuang Junlebao Dairy Co. Ltd, Shijiazhuang 050221, China
| | - Lianzhong Ai
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instruments and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
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Abstract
All-atom molecular dynamics simulations can capture the dynamic degrees of freedom that characterize molecular recognition, the knowledge of which constitutes the cornerstone of rational approaches to drug design and optimization. In particular, enhanced sampling algorithms, such as metadynamics, are powerful tools to dramatically reduce the computational cost required for a mechanistic description of the binding process. Here, we describe the essential details characterizing these simulation strategies, focusing on the critical step of identifying suitable reaction coordinates, as well as on the different analysis algorithms to estimate binding affinity and residence times. We conclude with a survey of published applications that provides explicit examples of successful simulations for several targets.
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Affiliation(s)
- Davide Provasi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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45
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Pedersen MF, Wróbel TM, Märcher-Rørsted E, Pedersen DS, Møller TC, Gabriele F, Pedersen H, Matosiuk D, Foster SR, Bouvier M, Bräuner-Osborne H. Biased agonism of clinically approved μ-opioid receptor agonists and TRV130 is not controlled by binding and signaling kinetics. Neuropharmacology 2019; 166:107718. [PMID: 31351108 DOI: 10.1016/j.neuropharm.2019.107718] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 07/08/2019] [Accepted: 07/22/2019] [Indexed: 12/11/2022]
Abstract
Binding and signaling kinetics have previously proven important in validation of biased agonism at GPCRs. Here we provide a comprehensive kinetic pharmacological comparison of clinically relevant μ-opioid receptor agonists, including the novel biased agonist oliceridine (TRV130) which is in clinical trial for pain management. We demonstrate that the bias profile observed for the selected agonists is not time-dependent and that agonists with dramatic differences in their binding kinetic properties can display the same degree of bias. Binding kinetics analyses demonstrate that buprenorphine has 18-fold higher receptor residence time than oliceridine. This is thus the largest pharmacodynamic difference between the clinically approved drug buprenorphine and the clinical candidate oliceridine, since their bias profiles are similar. Further, we provide the first pharmacological characterization of (S)-TRV130 demonstrating that it has a similar pharmacological profile as the (R)-form, oliceridine, but displays 90-fold lower potency than the (R)-form. This difference is driven by a significantly slower association rate. Finally, we show that the selected agonists are differentially affected by G protein-coupled receptor kinase 2 and 5 (GRK2 and GRK5) expression. GRK2 and GRK5 overexpression greatly increased μ-opioid receptor internalization induced by morphine, but only had modest effects on buprenorphine and oliceridine-induced internalization. Overall, our data reveal that the clinically available drug buprenorphine displays a similar pharmacological bias profile in vitro compared to the clinical candidate drug oliceridine and that this bias is independent of binding kinetics suggesting a mechanism driven by receptor-conformations. This article is part of the Special Issue entitled 'New Vistas in Opioid Pharmacology'.
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Affiliation(s)
- Mie Fabricius Pedersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC, Canada
| | - Tomasz Marcin Wróbel
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Medical University of Lublin, Lublin, Poland
| | - Emil Märcher-Rørsted
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Sejer Pedersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Thor Christian Møller
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Federica Gabriele
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | | | - Dariusz Matosiuk
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Medical University of Lublin, Lublin, Poland
| | - Simon Richard Foster
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC, Canada.
| | - Hans Bräuner-Osborne
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
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46
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Abstract
The influence of drug-receptor binding kinetics has often been overlooked during the development of new therapeutics that target G protein-coupled receptors (GPCRs). Over the last decade there has been a growing understanding that an in-depth knowledge of binding kinetics at GPCRs is required to successfully target this class of proteins. Ligand binding to a GPCR is often not a simple single step process with ligand freely diffusing in solution. This review will discuss the experiments and equations that are commonly used to measure binding kinetics and how factors such as allosteric regulation, rebinding and ligand interaction with the plasma membrane may influence these measurements. We will then consider the molecular characteristics of a ligand and if these can be linked to association and dissociation rates.
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Affiliation(s)
- David A Sykes
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Leigh A Stoddart
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Laura E Kilpatrick
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Stephen J Hill
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.
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47
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Garcia J, Patel N, Basehore S, Clyne AM. Fibroblast Growth Factor-2 Binding to Heparan Sulfate Proteoglycans Varies with Shear Stress in Flow-Adapted Cells. Ann Biomed Eng 2019; 47:1078-1093. [PMID: 30689065 PMCID: PMC6470077 DOI: 10.1007/s10439-019-02202-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 01/08/2019] [Indexed: 12/19/2022]
Abstract
Fibroblast growth factor 2 (FGF2), an important regulator of angiogenesis, binds to endothelial cell (EC) surface FGF receptors (FGFRs) and heparan sulfate proteoglycans (HSPGs). FGF2 binding kinetics have been predominantly studied in static culture; however, the endothelium is constantly exposed to flow which may affect FGF2 binding. We therefore used experimental and computational techniques to study how EC FGF2 binding changes in flow. ECs adapted to 24 h of flow demonstrated biphasic FGF2-HSPG binding, with FGF2-HSPG complexes increasing up to 20 dynes/cm2 shear stress and then decreasing at higher shear stresses. To understand how adaptive EC surface remodeling in response to shear stress may affect FGF2 binding to FGFR and HSPG, we implemented a computational model to predict the relative effects of flow-induced surface receptor changes. We then fit the computational model to the experimental data using relationships between HSPG availability and FGF2-HSPG dissociation and flow that were developed from a basement membrane study, as well as including HSPG production. These studies suggest that FGF2 binding kinetics are altered in flow-adapted ECs due to changes in cell surface receptor quantity, availability, and binding kinetics, which may affect cell growth factor response.
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Affiliation(s)
- Jonathan Garcia
- School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut St, Philadelphia, PA, USA
| | - Nisha Patel
- School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut St, Philadelphia, PA, USA
| | - Sarah Basehore
- School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut St, Philadelphia, PA, USA
| | - Alisa Morss Clyne
- Mechanical Engineering and Mechanics Department, Drexel University, 3141 Chestnut St, Philadelphia, PA, USA.
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48
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Bouzo-Lorenzo M, Stoddart LA, Xia L, IJzerman AP, Heitman LH, Briddon SJ, Hill SJ. A live cell NanoBRET binding assay allows the study of ligand- binding kinetics to the adenosine A 3 receptor. Purinergic Signal 2019; 15:139-53. [PMID: 30919204 DOI: 10.1007/s11302-019-09650-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 02/14/2019] [Indexed: 01/14/2023] Open
Abstract
There is a growing interest in understanding the binding kinetics of compounds that bind to G protein-coupled receptors prior to progressing a lead compound into clinical trials. The widely expressed adenosine A3 receptor (A3AR) has been implicated in a range of diseases including immune conditions, and compounds that aim to selectively target this receptor are currently under development for arthritis. Kinetic studies at the A3AR have been performed using a radiolabelled antagonist, but due to the kinetics of this probe, they have been carried out at 10 °C in membrane preparations. In this study, we have developed a live cell NanoBRET ligand binding assay using fluorescent A3AR antagonists to measure kinetic parameters of labelled and unlabelled compounds at the A3AR at physiological temperatures. The kinetic profiles of four fluorescent antagonists were determined in kinetic association assays, and it was found that XAC-ser-tyr-X-BY630 had the longest residence time (RT = 288 ± 62 min) at the A3AR. The association and dissociation rate constants of three antagonists PSB-11, compound 5, and LUF7565 were also determined using two fluorescent ligands (XAC-ser-tyr-X-BY630 or AV039, RT = 6.8 ± 0.8 min) as the labelled probe and compared to those obtained using a radiolabelled antagonist ([3H]PSB-11, RT = 44.6 ± 3.9 min). There was close agreement in the kinetic parameters measured with AV039 and [3H]PSB-11 but significant differences to those obtained using XAC-S-ser-S-tyr-X-BY630. These data indicate that selecting a probe with the appropriate kinetics is important to accurately determine the kinetics of unlabelled ligands with markedly different kinetic profiles.
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49
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Weinberg J, Zhang S, Crews G, Carta G, Przybycien T. Chemical modification of protein A chromatography ligands with polyethylene glycol. I: Effects on IgG adsorption equilibrium, kinetics, and transport. J Chromatogr A 2018; 1546:77-88. [PMID: 29551236 DOI: 10.1016/j.chroma.2018.03.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 02/27/2018] [Accepted: 03/07/2018] [Indexed: 10/17/2022]
Abstract
Chemical modification of Protein A (ProA) chromatography ligands with polyethylene glycol (PEGylation) has been proposed as a strategy to increase the process selectivity and resin robustness by providing the ligand with a steric repulsion barrier against non-specific binding. This article comprises a comprehensive study of IgG adsorption and transport in Repligen CaptivA PriMAB resin with PEGylated ProA ligands that are modified using 5.2 and 21.5 kDa PEG chains. We studied the impact of the molecular weight of the PEG as well as the extent of PEGylation for the 5.2 kDa PEG modification. In all cases, PEGylation of ProA ligands decreases the resin average pore size, particle porosity, and static binding capacity for IgG proportional to the volume of conjugated PEG in the resin. Resin batch uptake experiments conducted in bulk via a stirred-tank system and with individual resin particles under confocal laser scanning microscopy suggests that PEGylation introduces heterogeneity into IgG binding kinetics: a fraction of the IgG binding sites are transformed from typical fast association kinetic behavior to slow kinetic behavior. pH gradient elution experiments of an IgG molecule on the modified resins show an increase in IgG elution pH for all modified resins, implying a decrease in IgG-ProA binding affinity on modification. Despite losses in static binding capacity for all resins with PEGylated ligands, the loss of dynamic binding capacity at 10% breakthrough (DBC10%) ranged more broadly from almost 0-47% depending on the PEG molecular weight and the extent of PEGylation. Minimal losses in DBC10% were observed with a low extent of PEGylation with a smaller molecular weight PEG, while higher losses were observed at higher extents of PEGylation and with higher molecular weight PEG due to decreased static binding capacity and increased mass transfer resistance. This work provides insight into the practical implications for resin performance if PEGylation is considered as a strategy for selectivity enhancement in affinity chromatography with macromolecular ligands.
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Affiliation(s)
- Justin Weinberg
- Department of Chemical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
| | - Shaojie Zhang
- Department of Chemical Engineering, University of Virginia, 102 Engineers' Way, Charlottesville, VA 22904, USA
| | - Gillian Crews
- Department of Chemical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
| | - Giorgio Carta
- Department of Chemical Engineering, University of Virginia, 102 Engineers' Way, Charlottesville, VA 22904, USA
| | - Todd Przybycien
- Department of Chemical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
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50
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Xia L, Kyrizaki A, Tosh DK, van Duijl TT, Roorda JC, Jacobson KA, IJzerman AP, Heitman LH. A binding kinetics study of human adenosine A 3 receptor agonists. Biochem Pharmacol 2018; 153:248-59. [PMID: 29305857 DOI: 10.1016/j.bcp.2017.12.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/29/2017] [Indexed: 02/07/2023]
Abstract
The human adenosine A3 (hA3) receptor has been suggested as a viable drug target in inflammatory diseases and in cancer. So far, a number of selective hA3 receptor agonists (e.g. IB-MECA and 2-Cl-IB-MECA) inducing anti-inflammatory or anticancer effects are under clinical investigation. Drug-target binding kinetics is increasingly recognized as another pharmacological parameter, next to affinity, for compound triage in the early phases of drug discovery. However, such a kinetics-driven analysis has not yet been performed for the hA3 receptor. In this study, we first validated a competition association assay for adenosine A3 receptor agonists to determine the target interaction kinetics. Affinities and Kinetic Rate Index (KRI) values of 11 ribofurano and 10 methanocarba nucleosides were determined in radioligand binding assays. Afterwards, 15 analogues were further selected (KRI <0.70 or KRI >1.35) for full kinetics characterization. The structure-kinetics relationships (SKR) were derived and longer residence times were associated with methanocarba and enlarged adenine N6 and C2 substitutions. In addition, from a kon-koff-KD kinetic map we divided the agonists into three subgroups. A residence time "cliff" was observed, which might be relevant to (N)-methanocarba derivatives' rigid C2-arylalkynyl substitutions. Our findings provide substantial evidence that, next to affinity, additional knowledge of binding kinetics is useful for developing and selecting new hA3R agonists in the early phase of the drug discovery process.
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