181 results on '"McPherson MJ"'
Search Results
2. The role of emotion in musical improvisation: An analysis of structural features
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Limb, Charles, McPherson, MJ, Lopez-Gonzalez, M, Rankin, SK, and Limb, CJ
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One of the primary functions of music is to convey emotion, yet how music accomplishes this task remains unclear. For example, simple correlations between mode (major vs. minor) and emotion (happy vs. sad) do not adequately explain the enormous range, subt
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- 2014
3. Reagentless Affimer- and antibody-based impedimetric biosensors for CEA-detection using a novel non-conducting polymer
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Shamsuddin, SH, Gibson, TD, Tomlinson, DC, McPherson, MJ, Jayne, DG, and Millner, PA
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Polyoctopamine (POct), an amine-functionalised non-conducting polymer, as the transducer layer in an electrochemical biosensor, is presented. This polymer offers versatile covalent coupling either through thiol linker conjugation, carboxyl or aldehyde functional groups without the requirement of pre- or post-surface activation. The colorectal cancer biomarker carcinoembryonic antigen (CEA) was selected as the target analyte, whilst an antibody and a synthetic binding protein, an Affimer, were used as distinct bioreceptors to demonstrate the versatility of polyoctopamine as a transducer polymer layer for oriented immobilisation of the bioreceptors. The electrodeposited polymer layer was characterised using cyclic voltammetry, electrochemical impedance spectroscopy, and on-sensor chemiluminescent blotting. The performance of optimised POct-based biosensors were tested in spiked human serum. Results showed that the electropolymerisation of octopamine on screen printed gold electrode generates a thin polymer film with low resistance. Close proximity of the immobilised bioreceptors to the transducer layer greatly enhanced the sensitivity detection. The sensitivity of the smaller monomeric bioreceptor (Affimer, 12.6 kDa) to detect CEA was comparable to the dimeric antibody (150 kDa) with limit of detection at 11.76 fM which is significantly lower than the basal clinical levels of 25 pM. However, the Affimer-based sensor had a narrower dynamic range compared to the immunosensor (1–100 fM vs. 1 fM – 100 nM, respectively). All electrochemical measurements were done in less than 5 min with small sample volumes (10 μl). Hence, polyoctopamine features a simple fabrication of impedimetric biosensors using amine-functionalisation technique, provides rapid response time with enhanced sensitivity and label-free detection.
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- 2021
4. Affinity purification of fibrinogen using an Affimer column
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Pechlivani, N, Kearney, KJ, Tiede, C, Cheah, R, Phoenix, F, Ponnambalam, S, Ault, JR, McPherson, MJ, Tomlinson, DC, and Ajjan, RA
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Fibrin ,Hemostasis ,Biophysics ,Fibrinogen ,Humans ,Plasminogen ,Molecular Biology ,Biochemistry ,Chromatography, Affinity - Abstract
Background Fibrinogen is an abundant plasma protein with an essential role in blood coagulation and haemostasis thus receiving significant research interest. However, protein purification is time consuming and commercial preparations often have protein contaminants. The aim of this study was to develop a new method to purify high quality and functional fibrinogen. Methods Fibrinogen-specific Affimer protein, isolated using phage display systems, was immobilised to SulfoLink resin column and employed for fibrinogen purification from plasma samples. Fibrinogen was eluted using a high pH solution. Commercial human fibrinogen was also further purified using the Affimer column. Fibrinogen purity was determined by SDS-PAGE and mass spectrometry, while functionality was assessed using turbidimetric analysis. Results Affimer-purified fibrinogen from human plasma showed purity at least comparable to commercially available preparations and was able to form physiological fibrin networks. Further purification of commercially available fibrinogen using the Affimercolumn eliminated multiple contaminant proteins, a significant number of which are key elements of the coagulation cascade, including plasminogen and factor XIII. Conclusions The Affimercolumn represents a proof of concept novel, rapid method for isolating functional fibrinogen from plasma and for further purification of commercially available fibrinogen preparations. General significance Our methodology provides an efficient way of purifying functional fibrinogen with superior purity without the need of expensive pieces of equipment or the use of harsh conditions.
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- 2022
5. Passive Picoinjection Enables Controlled Crystallization in a Droplet Microfluidic Device
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Li, S, Zeng, M, Gaule, T, McPherson, MJ, and Meldrum, FC
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Segmented flow microfluidic devices offer an attractive means of studying crystallization processes. However, while they are widely employed for protein crystallization, there are few examples of their use for sparingly soluble compounds due to problems with rapid device fouling and irreproducibility over longer run‐times. This article presents a microfluidic device which overcomes these issues, as this is constructed around a novel design of “picoinjector” that facilitates direct injection into flowing droplets. Exploiting a Venturi junction to reduce the pressure within the droplet, it is shown that passive injection of solution from a side‐capillary can be achieved in the absence of an applied electric field. The operation of this device is demonstrated for calcium carbonate, where highly reproducible results are obtained over long run‐times at high supersaturations. This compares with conventional devices that use a Y‐junction to achieve solution loading, where in‐channel precipitation of calcium carbonate occurs even at low supersaturations. This work not only opens the door to the use of microfluidics to study the crystallization of low solubility compounds, but the simple design of a passive picoinjector will find wide utility in areas including multistep reactions and investigation of reaction dynamics.
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- 2017
6. Adhiron: a stable and versatile peptide display scaffold for molecular recognition applications
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Tiede, C, Tang, AA, Deacon, SE, Mandal, U, Nettleship, JE, Owen, RL, George, SE, Harrison, DJ, Owens, RJ, Tomlinson, DC, and McPherson, MJ
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RM ,Q1 ,R1 - Abstract
We have designed a novel non-antibody scaffold protein, termed Adhiron, based on a phytocystatin consensus sequence. The Adhiron scaffold shows high thermal stability (Tm ca. 101°C), and is expressed well in Escherichia coli. We have determined the X-ray crystal structure of the Adhiron scaffold to 1.75 Å resolution revealing a compact cystatin-like fold. We have constructed a phage-display library in this scaffold by insertion of two variable peptide regions. The library is of high quality and complexity comprising 1.3 × 10(10) clones. To demonstrate library efficacy, we screened against the yeast Small Ubiquitin-like Modifier (SUMO). In selected clones, variable region 1 often contained sequences homologous to the known SUMO interactive motif (V/I-X-V/I-V/I). Four Adhirons were further characterised and displayed low nanomolar affinities and high specificity for yeast SUMO with essentially no cross-reactivity to human SUMO protein isoforms. We have identified binders against >100 target molecules to date including as examples, a fibroblast growth factor (FGF1), platelet endothelial cell adhesion molecule (PECAM-1; CD31), the SH2 domain Grb2 and a 12-aa peptide. Adhirons are highly stable and well expressed allowing highly specific binding reagents to be selected for use in molecular recognition applications.
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- 2014
7. A7.08 Novel agents for blocking the interaction of immune complexes with the activatory FCγRIIIA receptor
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Baxter, EW, primary, Robinson, JI, additional, Tomlinson, DC, additional, Foster, RJ, additional, Owen, RL, additional, Win, SJ, additional, Nettleship, JE, additional, Tiede, C, additional, Kankanala, J, additional, Owens, RJ, additional, Fishwick, CWG, additional, McPherson, MJ, additional, and Morgan, AW, additional
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- 2016
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8. Kinetic Studies on the Redox Interconversion of GOasesemi and GOaseox Forms of Galactose Oxidase with Inorganic Complexes as Redox Partners
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Colin G. Saysell, Christopher D. Borman, Baron Aj, McPherson Mj, and A. G. Sykes
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Inorganic Chemistry ,chemistry.chemical_classification ,Enzyme ,chemistry ,Stereochemistry ,Galactose oxidase ,Organic chemistry ,Physical and Theoretical Chemistry ,Redox - Abstract
Redox interconversions between the GOase(semi) (Cu(II), Tyr) and tyrosyl radical containing GOase(ox) (Cu(II), Tyr(*)) oxidation states of the Cu-containing enzyme galactose oxidase (GOase) from Fusarium NRRL 2903 have been studied. The inorganic complexes [Fe(CN)(6)](3)(-) (410 mV), [Co(phen)(3)](3+) (370 mV), [W(CN)(8)](3)(-) (530 mV), and [Co(dipic)(2)](-) (362 mV) (E degrees ' values vs NHE; dipic = 2,6-dicarboxylatopyridine) were used as oxidants for GOase(semi), and [Fe(CN)(6)](4)(-) and [Co(phen)(3)](2+) as reductants for GOase(ox). On oxidation of GOase(semi) a radical is generated at the coordinated phenolate of Tyr-272 to give GOase(ox). The one-electron reduction potential E degrees ' (25 degrees C) for the GOase(ox)/GOase(semi) couple varies with pH and is 400 mV vs NHE at pH 7.5, the smallest value so far observed for a tyrosyl radical. The reactions are very sensitive to pH, or more precisely to pK(a) values of GOase(semi) and GOase(ox), and the charge on the inorganic reagent. For example, with [Fe(CN)(6)](3)(-) as oxidant, the rate constant (25 degrees C)/M(-)(1) s(-)(1) of 0.16 x 10(3) (pH approximately 9.5) increases to 4.3 x 10(3) (pH approximately 5.5), while for [Co(phen)(3)](3+) a value of 4.9 x 10(3) (pH approximately 9.5) decreases to 0.04 x 10(3) (pH approximately 5.5), I = 0.100 M (NaCl). From the kinetics a single GOase(semi) acid dissociation process, pK(a) = 8.0 (average), has been confirmed by UV-vis spectrophotometric studies (7.9). The corresponding value for GOase(ox) is 6.7. No comparable kinetic or spectrophotometric pH dependences are observed with the Tyr495Phe variant, indicating the axial Tyr-495 as the site of protonation. Neutral CH(3)CO(2)H and HN(3) species bind at the substrate binding site of GOase(semi), thus mimicking the behavior of primary alcohols RCH(2)OH, the natural substrate of GOase. On coordination, loss of a proton occurs, and inhibition of the oxidation with [Fe(CN)(6)](3)(-) is observed.
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- 1997
9. In vitro and in vivo characterization of A-940894: a potent histamine H4 receptor antagonist with anti-inflammatory properties
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Strakhova, MI, primary, Cuff, CA, additional, Manelli, AM, additional, Carr, TL, additional, Witte, DG, additional, Baranowski, JL, additional, Vortherms, TA, additional, Miller, TR, additional, Rundell, L, additional, McPherson, MJ, additional, Adair, RM, additional, Brito, AA, additional, Bettencourt, BM, additional, Yao, BB, additional, Wetter, JM, additional, Marsh, KC, additional, Liu, H, additional, Cowart, MD, additional, Brioni, JD, additional, and Esbenshade, TA, additional
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- 2009
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10. A movie of catalysis in the copper-containing quinoenzyme amine oxidase
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Wilmot, CM, Hajdu, J, Saysell, CG, McPherson, MJ, Knowles, PF, Phillips, SEV, Wilmot, CM, Hajdu, J, Saysell, CG, McPherson, MJ, Knowles, PF, and Phillips, SEV
- Abstract
Addresses: Univ Leeds, Sch Biochem & Mol Biol, Leeds LS2 9JT, W Yorkshire, England. Univ Uppsala, Dept Biochem, S-75123 Uppsala, Sweden.
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- 1999
11. Visualization of dioxygen bound to copper during enzyme catalysis
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Wilmot, CM, Hajdu, J, McPherson, MJ, Knowles, PF, Phillips, SEV, Wilmot, CM, Hajdu, J, McPherson, MJ, Knowles, PF, and Phillips, SEV
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X-ray crystal structures of three species related to the oxidative half of the reaction of the copper-containing quinoprotein amine oxidase from Escherichia coli have been determined. Crystals were freeze-trapped either anaerobically or aerobically after, Addresses: Wilmot CM, Univ Leeds, Sch Biochem & Mol Biol, Astbury Ctr Struct Mol Biol, Leeds LS2 9JT, W Yorkshire, England. Univ Leeds, Sch Biochem & Mol Biol, Astbury Ctr Struct Mol Biol, Leeds LS2 9JT, W Yorkshire, England. Univ Uppsala, Dept Biochem
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- 1999
12. The effects of protease inhibitors on the murine parasite Heligmosomoides polygyrus
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Devlin, P, primary, Beggs, K, additional, McPherson, MJ, additional, and Atkinson, HJ, additional
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- 1998
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13. Crystal structure of a quinoenzyme: copper amine oxidase of Escherichia coli at 2 å resolution
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Parsons, MR, primary, Convery, MA, additional, Wilmot, CM, additional, Yadav, KDS, additional, Blakeley, V, additional, Corner, AS, additional, Phillips, SEV, additional, McPherson, MJ, additional, and Knowles, PF, additional
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- 1995
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14. Polymerase chain reaction amplification of the RuBisCo small subunit genes and their novel application to plant tissue identification.
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APPLEBY, JM, NELSON, G, McPHERSON, MJ, and HAMLYN, PF
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PLANT cells & tissues ,PLANT genetics ,POLYMERASE chain reaction ,GENE amplification - Abstract
Degenerate polymerase chain reaction (PCR) primers and specific PCR conditions have been developed for the selective amplification of a polymorphic region of ribulose-1,5-bisphosphate carboxylase (RuBisCo) small subunit (ssu) genes. Reliable amplification has been achieved for genes from more than 20 plant species from a variety of taxonomic groups. Analysis of Nicotiana species provides strong evidence that the test loci are polymorphic at the interspecies level but show little polymorphic variation at the intraspecies level. This specific multilocus PCR approach provides a powerful counterpart to random amplification of polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) analysis for the identification of plant tissues. [ABSTRACT FROM AUTHOR]
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- 1997
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15. Label-free electrochemical impedance biosensor to detect human interleukin-8 in serum with sub-pg/ml sensitivity
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Sharma, R, Deacon, Sarah E., Nowak, D, George, SE, Szymonic, MP, Tang, AAS, Tomlinson, DC, Davies, AG, McPherson, MJ, and Walti, C
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Antibody mimetic protein ,Point-of-care diagnostics ,Interleukin-8 ,CXCL8 ,Biophysics ,Electrochemistry ,Biomedical Engineering ,Label-free biosensor ,Q1 ,R1 ,Electrochemical impedance spectroscopy ,QC ,Biotechnology - Abstract
Biosensors with high sensitivity and short time-to-result that are capable of detecting biomarkers in body fluids such as serum are an important prerequisite for early diagnostics in modern healthcare provision. Here, we report the development of an electrochemical impedance-based sensor for the detection in serum of human interleukin-8 (IL-8), a pro-angiogenic chemokine implicated in a wide range of inflammatory diseases. The sensor employs a small and robust synthetic non-antibody capture protein based on a cystatin scaffold that displays high affinity for human IL-8 with a KD of 35 ± 10 nM and excellent ligand specificity. The change in the phase of the electrochemical impedance from the serum baseline, ∆θ(ƒ), measured at 0.1 Hz, was used as the measure for quantifying IL-8 concentration in the fluid. Optimal sensor signal was observed after 15 min incubation, and the sensor exhibited a linear response versus logarithm of IL-8 concentration from 900 fg/ml to 900 ng/ml. A detection limit of around 90 fg/ml, which is significantly lower than the basal clinical levels of 5-10 pg/ml, was observed. Our results are significant for the development of point-of-care and early diagnostics where high sensitivity and short time-to-results are essential.
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16. Generating and validating renewable affimer protein binding reagents targeting SH2 domains.
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Heseltine SJ, Billenness GJ, Martin HL, Tiede C, Tang AAS, Foy E, Reddy G, Gibson N, Johnson M, Webb ME, McPherson MJ, and Tomlinson DC
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- Humans, Indicators and Reagents chemistry, src Homology Domains, GRB2 Adaptor Protein metabolism, GRB2 Adaptor Protein chemistry, GRB2 Adaptor Protein antagonists & inhibitors, Protein Binding
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Despite SH2 domains, being pivotal in protein interactions linked to various diseases like cancer, we lack specific research tools for intracellular assays. Understanding SH2-mediated interactions and creating effective inhibitors requires tools which target individual protein domains. Affimer reagents exhibit promise, yet their potential against the extensive SH2 domain family remains largely unexplored. Our study aimed to bridge this gap by identifying Affimer reagents that selectively bind to 22 out of 41 SH2 domains. These reagents enabled a medium-throughput screening approach resembling siRNA studies, shedding light on their functionality. Notably, select Affimers demonstrated the ability to curtail the nuclear translocation of pERK, with Grb2 being a prominent target. Further analyses revealed that these Grb2-specific Affimer reagents displayed competitive inhibition with impressive metrics: IC50s ranging from 270.9 nM to 1.22 µM, together with low nanomolar binding affinities. Moreover, they exhibited the ability to pull down endogenous Grb2 from cell lysates, illustrating their efficacy in binding the Grb2 SH2 domain. This comprehensive assessment underscores the potential of Affimer reagents as domain-specific inhibitors. Their viability for medium/high-throughput phenotypic screening presents a promising avenue via which to identify and characterize potential drug targets within the SH2 domain family., Competing Interests: Declarations Competing interests MJ is an employee of Avacta Life Sciences and holds shares in the company, the Affimer technology is licensed to Avacta Life Sciences by the University of Leeds. The royalties from the license are managed by ULIP at the University of Leeds and disseminated to the inventors DCT and MJM. All other authors do not have a competing interest., (© 2024. The Author(s).)
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- 2024
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17. Targeting Grb2 SH3 Domains with Affimer Proteins Provides Novel Insights into Ras Signalling Modulation.
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Tang AAS, Macdonald A, McPherson MJ, and Tomlinson DC
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- Humans, Protein Binding, SOS1 Protein metabolism, SOS1 Protein chemistry, SOS1 Protein genetics, Epidermal Growth Factor metabolism, GRB2 Adaptor Protein metabolism, src Homology Domains, Signal Transduction drug effects, ras Proteins metabolism
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Src homology 3 (SH3) domains play a critical role in mediating protein-protein interactions (PPIs) involved in cell proliferation, migration, and the cytoskeleton. Despite their abundance in the human proteome, the functions and molecular interactions of many SH3 domains remain unknown, and this is in part due to the lack of SH3-domain-specific reagents available for their study. Affimer proteins have been developed as affinity reagents targeting a diverse range of targets, including those involved in PPIs. In this study, Affimer proteins were isolated against both the N- and C-terminal SH3 domains (NSH3 and CSH3) of growth-factor-receptor-bound protein 2 (Grb2), an adapter protein that provides a critical link between cell surface receptors and Ras signalling pathways. Targeting the CSH3 alone for the inhibition of PPIs appeared sufficient for curtailing Ras signalling in mammalian cell lines stimulated with human epidermal growth factor (EGF), which conflicts with the notion that the predominant interactions with Ras activating Son of sevenless (SOS) occur via the NSH3 domain. This result supports a model in which allosteric mechanisms involved in Grb2-SOS1 interaction modulate Ras activation.
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- 2024
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18. Anti-TNF Thioester Glucocorticoid Antibody-Drug Conjugate Fully Inhibits Inflammation with Minimal Effect on Systemic Corticosterone Levels in a Mouse Arthritis Model.
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Marvin CC, Hobson AD, McPherson MJ, Hayes ME, Patel MV, Schmidt DL, Li T, Randolph JT, Bischoff AK, Fitzgibbons J, Wang L, Wang L, Hernandez A Jr, Jia Y, Goess CA, Bryant SH, Mathieu SL, and Xu J
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- Animals, Mice, Receptors, Glucocorticoid metabolism, Receptors, Glucocorticoid antagonists & inhibitors, Inflammation drug therapy, Inflammation metabolism, Glucocorticoids pharmacology, Humans, Male, Disease Models, Animal, Arthritis, Experimental drug therapy, Arthritis, Experimental metabolism, Immunoconjugates pharmacology, Immunoconjugates chemistry, Immunoconjugates pharmacokinetics, Immunoconjugates therapeutic use, Corticosterone blood, Tumor Necrosis Factor-alpha metabolism, Tumor Necrosis Factor-alpha antagonists & inhibitors
- Abstract
We describe the discovery of a thioester-containing glucocorticoid receptor modulator (GRM) payload and the corresponding antibody-drug conjugate (ADC). Payload 6 was designed for rapid hepatic inactivation to minimize systemic exposure of nonconjugated GRM. Mouse PK indicated that 6 is cleared 10-fold more rapidly than a first-generation GRM payload, resulting in 10-fold lower exposure and 3-fold decrease in Cmax. The anti-mTNF conjugate ADC5 fully inhibited inflammation in mouse contact hypersensitivity with minimal effects on corticosterone, a biomarker for systemic GRM effects, at doses up to and including 100 mg/kg. Concomitant inhibition of P1NP suggests potential delivery to cells involved in the remodeling of bone, which may be a consequence of TNF-targeting or bystander payload effects. Furthermore, ADC5 fully suppressed inflammation in collagen-induced arthritis mouse model after one 10 mg/kg dose for 21 days. The properties of the anti-hTNF conjugate were suitable for liquid formulation and may enable subcutaneous dosing.
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- 2024
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19. Commonality and variation in mental representations of music revealed by a cross-cultural comparison of rhythm priors in 15 countries.
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Jacoby N, Polak R, Grahn JA, Cameron DJ, Lee KM, Godoy R, Undurraga EA, Huanca T, Thalwitzer T, Doumbia N, Goldberg D, Margulis EH, Wong PCM, Jure L, Rocamora M, Fujii S, Savage PE, Ajimi J, Konno R, Oishi S, Jakubowski K, Holzapfel A, Mungan E, Kaya E, Rao P, Rohit MA, Alladi S, Tarr B, Anglada-Tort M, Harrison PMC, McPherson MJ, Dolan S, Durango A, and McDermott JH
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- Humans, Male, Adult, Female, Young Adult, Cognition physiology, Music psychology, Cross-Cultural Comparison, Auditory Perception physiology
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Music is present in every known society but varies from place to place. What, if anything, is universal to music cognition? We measured a signature of mental representations of rhythm in 39 participant groups in 15 countries, spanning urban societies and Indigenous populations. Listeners reproduced random 'seed' rhythms; their reproductions were fed back as the stimulus (as in the game of 'telephone'), such that their biases (the prior) could be estimated from the distribution of reproductions. Every tested group showed a sparse prior with peaks at integer-ratio rhythms. However, the importance of different integer ratios varied across groups, often reflecting local musical practices. Our results suggest a common feature of music cognition: discrete rhythm 'categories' at small-integer ratios. These discrete representations plausibly stabilize musical systems in the face of cultural transmission but interact with culture-specific traditions to yield the diversity that is evident when mental representations are probed across many cultures., (© 2024. The Author(s).)
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- 2024
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20. An anti-TNF-glucocorticoid receptor modulator antibody-drug conjugate is efficacious against immune-mediated inflammatory diseases.
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McPherson MJ, Hobson AD, Hernandez A Jr, Marvin CC, Waegell W, Goess C, Oh JZ, Shi D, Hayes ME, Wang L, Wang L, Schmidt D, Wang Z, Pitney V, McCarthy K, Jia Y, Wang C, Kang BN, Bryant S, Mathieu S, Ruzek M, Parmentier J, D'Cunha RR, Pang Y, Phillips L, Brown NJ, Xu J, Graff C, Tian Y, Longenecker KL, Qiu W, Zhu H, Liu W, Zheng P, Bi Y, and Stoffel R
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- Humans, Animals, Mice, Pharmaceutical Preparations, Receptors, Glucocorticoid therapeutic use, Tumor Necrosis Factor Inhibitors therapeutic use, Glucocorticoids pharmacology, Glucocorticoids therapeutic use, Tumor Necrosis Factor-alpha metabolism, Disease Models, Animal, Arthritis, Experimental, Immunoconjugates pharmacology, Immunoconjugates therapeutic use, Antibodies, Steroids
- Abstract
Glucocorticoids (GCs) are efficacious drugs used for treating many inflammatory diseases, but the dose and duration of administration are limited because of severe side effects. We therefore sought to identify an approach to selectively target GCs to inflamed tissue. Previous work identified that anti-tumor necrosis factor (TNF) antibodies that bind to transmembrane TNF undergo internalization; therefore, an anti-TNF antibody-drug conjugate (ADC) would be mechanistically similar, where lysosomal catabolism could release a GC receptor modulator (GRM) payload to dampen immune cell activity. Consequently, we have generated an anti-TNF-GRM ADC with the aim of inhibiting pro-inflammatory cytokine production from stimulated human immune cells. In an acute mouse model of contact hypersensitivity, a murine surrogate anti-TNF-GRM ADC inhibited inflammatory responses with minimal effect on systemic GC biomarkers. In addition, in a mouse model of collagen-induced arthritis, single-dose administration of the ADC, delivered at disease onset, was able to completely inhibit arthritis for greater than 30 days, whereas an anti-TNF monoclonal antibody only partially inhibited disease. ADC treatment at the peak of disease was also able to attenuate the arthritic phenotype. Clinical data for a human anti-TNF-GRM ADC (ABBV-3373) from a single ascending dose phase 1 study in healthy volunteers demonstrated antibody-like pharmacokinetic profiles and a lack of impact on serum cortisol concentrations at predicted therapeutic doses. These data suggest that an anti-TNF-GRM ADC may provide improved efficacy beyond anti-TNF alone in immune mediated diseases while minimizing systemic side effects associated with standard GC treatment.
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- 2024
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21. "Affimer" synthetic protein scaffolds block oxidized LDL binding to the LOX-1 scavenger receptor and inhibit ERK1/2 activation.
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Roper BWR, Tiede C, Abdul-Zani I, Cuthbert GA, Jade D, Al-Aufi A, Critchley WR, Saikia Q, Homer-Vanniasinkam S, Sawamura T, McPherson MJ, Harrison MA, Tomlinson DC, and Ponnambalam S
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- Humans, HEK293 Cells, Lipoproteins, LDL metabolism, Receptors, Scavenger metabolism, Lectins metabolism, Scavenger Receptors, Class E genetics, Scavenger Receptors, Class E chemistry, Scavenger Receptors, Class E metabolism, MAP Kinase Signaling System
- Abstract
In multicellular organisms, a variety of lipid-protein particles control the systemic flow of triacylglycerides, cholesterol, and fatty acids between cells in different tissues. The chemical modification by oxidation of these particles can trigger pathological responses, mediated by a group of membrane proteins termed scavenger receptors. The lectin-like oxidized low-density lipoprotein (LOX-1) scavenger receptor binds to oxidized low-density lipoprotein (oxLDL) and mediates both signaling and trafficking outcomes. Here, we identified five synthetic proteins termed Affimers from a phage display library, each capable of binding recombinant LOX-1 extracellular (oxLDL-binding) domain with high specificity. These Affimers, based on a phytocystatin scaffold with loop regions of variable sequence, were able to bind to the plasma membrane of HEK293T cells exclusively when human LOX-1 was expressed. Binding and uptake of fluorescently labeled oxLDL by the LOX-1-expressing cell model was inhibited with subnanomolar potency by all 5 Affimers. ERK1/2 activation, stimulated by oxLDL binding to LOX-1, was also significantly inhibited (p < 0.01) by preincubation with LOX-1-specific Affimers, but these Affimers had no direct agonistic effect. Molecular modeling indicated that the LOX-1-specific Affimers bound predominantly via their variable loop regions to the surface of the LOX-1 lectin-like domain that contains a distinctive arrangement of arginine residues previously implicated in oxLDL binding, involving interactions with both subunits of the native, stable scavenger receptor homodimer. These data provide a new class of synthetic tools to probe and potentially modulate the oxLDL/LOX-1 interaction that plays an important role in vascular disease., Competing Interests: Conflicts of interest M. J. M. and D. C. T. are named inventors of the Affimer technology and this is filed under U.S. patent number #10,844,370 assigned to the University of Leeds on “Scaffold proteins derived from plant cystatins”., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2023
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22. Discovery of ABBV-154, an anti-TNF Glucocorticoid Receptor Modulator Immunology Antibody-Drug Conjugate (iADC).
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Hobson AD, Xu J, Welch DS, Marvin CC, McPherson MJ, Gates B, Liao X, Hollmann M, Gattner MJ, Dzeyk K, Sarvaiya H, Shenoy VM, Fettis MM, Bischoff AK, Wang L, Santora LC, Wang L, Fitzgibbons J, Salomon P, Hernandez A Jr, Jia Y, Goess CA, Mathieu SL, Bryant SH, Larsen ME, Cui B, and Tian Y
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- Receptors, Glucocorticoid, Tumor Necrosis Factor Inhibitors, Antibodies, Glucocorticoids, Maleimides, Prodrugs pharmacology, Immunoconjugates pharmacology
- Abstract
Stable attachment of drug-linkers to the antibody is a critical requirement, and for maleimide conjugation to cysteine, it is achieved by ring hydrolysis of the succinimide ring. During ADC profiling in our in-house property screening funnel, we discovered that the succinimide ring open form is in equilibrium with the ring closed succinimide. Bromoacetamide (BrAc) was identified as the optimal replacement, as it affords stable attachment of the drug-linker to the antibody while completely removing the undesired ring open-closed equilibrium. Additionally, BrAc also offers multiple benefits over maleimide, especially with respect to homogeneity of the ADC structure. In combination with a short, hydrophilic linker and phosphate prodrug on the payload, this afforded a stable ADC (ABBV-154) with the desired properties to enable long-term stability to facilitate subcutaneous self-administration.
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- 2023
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23. Optimization of Drug-Linker to Enable Long-term Storage of Antibody-Drug Conjugate for Subcutaneous Dosing.
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Hobson AD, Xu J, Marvin CC, McPherson MJ, Hollmann M, Gattner M, Dzeyk K, Fettis MM, Bischoff AK, Wang L, Fitzgibbons J, Wang L, Salomon P, Hernandez A Jr, Jia Y, Sarvaiya H, Goess CA, Mathieu SL, and Santora LC
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- Hydrophobic and Hydrophilic Interactions, Immunoconjugates chemistry
- Abstract
To facilitate subcutaneous dosing, biotherapeutics need to exhibit properties that enable high-concentration formulation and long-term stability in the formulation buffer. For antibody-drug conjugates (ADCs), the introduction of drug-linkers can lead to increased hydrophobicity and higher levels of aggregation, which are both detrimental to the properties required for subcutaneous dosing. Herein we show how the physicochemical properties of ADCs could be controlled through the drug-linker chemistry in combination with prodrug chemistry of the payload, and how optimization of these combinations could afford ADCs with significantly improved solution stability. Key to achieving this optimization is the use of an accelerated stress test performed in a minimal formulation buffer.
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- 2023
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24. Correction to "Discovery of ABBV-3373, an Anti-TNF Glucocorticoid Receptor Modulator Immunology Antibody Drug Conjugate".
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Hobson AD, McPherson MJ, Hayes ME, Goess C, Li X, Zhou J, Wang Z, Yu Y, Yang J, Sun L, Zhang Q, Qu P, Yang S, Hernandez A Jr, Bryant SH, Mathieu SL, Bischoff AK, Fitzgibbons J, Santora LC, Wang L, Wang L, Fettis MM, Li X, Marvin CC, Wang Z, Patel MV, Schmidt DL, Li T, Randolph JT, Henry RF, Graff C, Tian Y, Aguirre AL, and Shrestha A
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- 2023
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25. Correction to "Design and Development of Glucocorticoid Receptor Modulators as Immunology Antibody-Drug Conjugate Payloads".
- Author
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Hobson AD, McPherson MJ, Waegell W, Goess CA, Stoffel RH, Li X, Zhou J, Wang Z, Yu Y, Hernandez A Jr, Bryant SH, Mathieu SL, Bischoff AK, Fitzgibbons J, Pawlikowska M, Puthenveetil S, Santora LC, Wang L, Wang L, Marvin CC, Hayes ME, Shrestha A, Sarris KA, and Li B
- Published
- 2023
- Full Text
- View/download PDF
26. Relative pitch representations and invariance to timbre.
- Author
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McPherson MJ and McDermott JH
- Subjects
- Humans, Pitch Discrimination, Acoustic Stimulation, Pitch Perception, Music
- Abstract
Information in speech and music is often conveyed through changes in fundamental frequency (f0), perceived by humans as "relative pitch". Relative pitch judgments are complicated by two facts. First, sounds can simultaneously vary in timbre due to filtering imposed by a vocal tract or instrument body. Second, relative pitch can be extracted in two ways: by measuring changes in constituent frequency components from one sound to another, or by estimating the f0 of each sound and comparing the estimates. We examined the effects of timbral differences on relative pitch judgments, and whether any invariance to timbre depends on whether judgments are based on constituent frequencies or their f0. Listeners performed up/down and interval discrimination tasks with pairs of spoken vowels, instrument notes, or synthetic tones, synthesized to be either harmonic or inharmonic. Inharmonic sounds lack a well-defined f0, such that relative pitch must be extracted from changes in individual frequencies. Pitch judgments were less accurate when vowels/instruments were different compared to when they were the same, and were biased by the associated timbre differences. However, this bias was similar for harmonic and inharmonic sounds, and was observed even in conditions where judgments of harmonic sounds were based on f0 representations. Relative pitch judgments are thus not invariant to timbre, even when timbral variation is naturalistic, and when such judgments are based on representations of f0., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2023
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27. Discovery of ABBV-3373, an Anti-TNF Glucocorticoid Receptor Modulator Immunology Antibody Drug Conjugate.
- Author
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Hobson AD, McPherson MJ, Hayes ME, Goess C, Li X, Zhou J, Wang Z, Yu Y, Yang J, Sun L, Zhang Q, Qu P, Yang S, Hernandez A Jr, Bryant SH, Mathieu SL, Bischoff AK, Fitzgibbons J, Santora LC, Wang L, Wang L, Fettis MM, Li X, Marvin CC, Wang Z, Patel MV, Schmidt DL, Li T, Randolph JT, Henry RF, Graff C, Tian Y, Aguirre AL, and Shrestha A
- Subjects
- Animals, Humans, Mice, Receptors, Glucocorticoid, Tumor Necrosis Factor Inhibitors, Glucocorticoids, Immunoconjugates pharmacology, Immunoconjugates therapeutic use
- Abstract
Using a convergent synthetic route to enable multiple points of diversity, a series of glucocorticoid receptor modulators (GRM) were profiled for potency, selectivity, and drug-like properties in vitro . Despite covering a large range of diversity, profiling the nonconjugated small molecule was suboptimal and they were conjugated to a mouse antitumor necrosis factor (TNF) antibody using the MP-Ala-Ala linker. Screening of the resulting antibody drug conjugates (ADCs) provided a better assessment of efficacy and physical properties, reinforcing the need to conduct structure-activity relationship studies on the complete ADC. DAR4 ADCs were screened in an acute mouse contact hypersensitivity model measuring biomarkers to ensure a sufficient therapeutic window. In a chronic mouse arthritis model, mouse anti-TNF GRM ADCs were efficacious after a single dose of 10 mg/kg i.p. for over 30 days. Data on the unconjugated payloads and mouse surrogate anti-TNF ADCs identified payload 17 which was conjugated to a human anti-TNF antibody and advanced to the clinic as ABBV-3373.
- Published
- 2022
- Full Text
- View/download PDF
28. Rapid Quantification of C. difficile Glutamate Dehydrogenase and Toxin B (TcdB) with a NanoBiT Split-Luciferase Assay.
- Author
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Adamson H, Ajayi MO, Gilroy KE, McPherson MJ, Tomlinson DC, and Jeuken LJC
- Subjects
- Bacterial Proteins, Enterotoxins, Feces, Glutamate Dehydrogenase metabolism, Luciferases, Bacterial Toxins, Clostridioides difficile
- Abstract
C. difficile infection (CDI) is a leading healthcare-associated infection with a high morbidity and mortality and is a financial burden. No current standalone point-of-care test (POCT) is sufficient for the identification of true CDI over a disease-free carriage of C. difficile , so one is urgently required to ensure timely, appropriate treatment. Here, two types of binding proteins, Affimers and nanobodies, targeting two C. difficile biomarkers, glutamate dehydrogenase (GDH) and toxin B (TcdB), are combined in NanoBiT (NanoLuc Binary Technology) split-luciferase assays. The assays were optimized and their performance controlling parameters were examined. The 44 fM limit of detection (LoD), 4-5 log range and 1300-fold signal gain of the TcdB assay in buffer is the best observed for a NanoBiT assay to date. In the stool sample matrix, the GDH and TcdB assay sensitivity (LoD = 4.5 and 2 pM, respectively) and time to result (32 min) are similar to a current, commercial lateral flow POCT, but the NanoBit assay has no wash steps, detects clinically relevant TcdB over TcdA, and is quantitative. Development of the assay into a POCT may drive sensitivity further and offer an urgently needed ultrasensitive TcdB test for the rapid diagnosis of true CDI. The NanoBiTBiP (NanoBiT with Binding Proteins) system offers advantages over NanoBiT assays with antibodies as binding elements in terms of ease of production and assay performance. We expect this methodology and approach to be generally applicable to other biomarkers.
- Published
- 2022
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- View/download PDF
29. Harmonicity aids hearing in noise.
- Author
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McPherson MJ, Grace RC, and McDermott JH
- Subjects
- Auditory Perception, Auditory Threshold, Hearing, Hearing Tests, Humans, Noise, Pitch Discrimination, Hearing Aids, Speech Perception
- Abstract
Hearing in noise is a core problem in audition, and a challenge for hearing-impaired listeners, yet the underlying mechanisms are poorly understood. We explored whether harmonic frequency relations, a signature property of many communication sounds, aid hearing in noise for normal hearing listeners. We measured detection thresholds in noise for tones and speech synthesized to have harmonic or inharmonic spectra. Harmonic signals were consistently easier to detect than otherwise identical inharmonic signals. Harmonicity also improved discrimination of sounds in noise. The largest benefits were observed for two-note up-down "pitch" discrimination and melodic contour discrimination, both of which could be performed equally well with harmonic and inharmonic tones in quiet, but which showed large harmonic advantages in noise. The results show that harmonicity facilitates hearing in noise, plausibly by providing a noise-robust pitch cue that aids detection and discrimination., (© 2021. The Psychonomic Society, Inc.)
- Published
- 2022
- Full Text
- View/download PDF
30. Design and Development of Glucocorticoid Receptor Modulators as Immunology Antibody-Drug Conjugate Payloads.
- Author
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Hobson AD, McPherson MJ, Waegell W, Goess CA, Stoffel RH, Li X, Zhou J, Wang Z, Yu Y, Hernandez A Jr, Bryant SH, Mathieu SL, Bischoff AK, Fitzgibbons J, Pawlikowska M, Puthenveetil S, Santora LC, Wang L, Wang L, Marvin CC, Hayes ME, Shrestha A, Sarris KA, and Li B
- Subjects
- Animals, Antibodies, Mice, Receptors, Glucocorticoid, Antineoplastic Agents, Immunoconjugates pharmacology, Immunoconjugates therapeutic use
- Abstract
Glucocorticoid receptor modulators (GRM) are the first-line treatment for many immune diseases, but unwanted side effects restrict chronic dosing. However, targeted delivery of a GRM payload via an immunology antibody-drug conjugate (iADC) may deliver significant efficacy at doses that do not lead to unwanted side effects. We initiated our α-TNF-GRM ADC project focusing on identifying the optimal payload and a linker that afforded stable attachment to both the payload and antibody, resulting in the identification of the synthetically accessible maleimide-Gly-Ala-Ala linker. DAR 4 purified ADCs were shown to be more efficacious in a mouse contact hypersensitivity model than the parent α-TNF antibody. Analysis of P1NP and corticosterone biomarkers showed there was a sufficient therapeutic window between efficacy and unwanted effects. In a chronic mouse arthritis model, α-TNF-GRM ADCs were more efficacious than both the parent α-TNF mAb and an isotype control bearing the same GRM payload.
- Published
- 2022
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- View/download PDF
31. Separating clinical antibodies from repertoire antibodies, a path to in silico developability assessment.
- Author
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Negron C, Fang J, McPherson MJ, Stine WB Jr, and McCluskey AJ
- Subjects
- Chromatography, Gel, Humans, Antibodies, Monoclonal chemistry
- Abstract
Approaches for antibody discovery have seen substantial improvement and success in recent years. Yet, advancing antibodies into the clinic remains difficult because therapeutic developability concerns are challenging to predict. We developed a computational model to simplify antibody developability assessment and enable accelerated early-stage screening. To this end, we quantified the ability of hundreds of sequence- and structure-based descriptors to differentiate clinical antibodies that have undergone rigorous screening and characterization for drug-like properties from antibodies in the human repertoire that are not natively paired. This analysis identified 144 descriptors capable of distinguishing clinical from repertoire antibodies. Five descriptors were selected and combined based on performance and orthogonality into a single model referred to as the Therapeutic Antibody Developability Analysis (TA-DA). On a hold-out test set, this tool separated clinical antibodies from repertoire antibodies with an AUC = 0.8, demonstrating the ability to identify developability attributes unique to clinical antibodies. Based on our results, the TA-DA score may serve as an approach for selecting lead antibodies for further development. Abbreviations: Affinity-Capture Self-Interaction Nanoparticle Spectroscopy (AC-SINS), Area Under the Curve (AUC), Complementary-Determining Region (CDR), Clinical-Stage Therapeutics (CST), Framework (FR), Monoclonal Antibodies (mAbs), Observed Antibody Space (OAS), Receiver Operating Characteristic (ROC), Size-Exclusion Chromatography (SEC), Structural Aggregation Propensity (SAP), Therapeutic Antibody Developability Analysis (TA-DA), Therapeutic Antibody Profiler (TAP), Therapeutic Structural Antibody Database (Thera-SAbDab), Variable Heavy (VH), Variable Light (VL).
- Published
- 2022
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- View/download PDF
32. "Shake 'n Bake" Route to Functionalized Zr-UiO-66 Metal-Organic Frameworks.
- Author
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D'Amato R, Bondi R, Moghdad I, Marmottini F, McPherson MJ, Naïli H, Taddei M, and Costantino F
- Abstract
We report a novel synthetic procedure for the high-yield synthesis of metal-organic frameworks (MOFs) with fcu topology with a UiO-66-like structure starting from a range of commercial Zr
IV precursors and various substituted dicarboxylic linkers. The syntheses are carried out by grinding in a ball mill the starting reagents, namely, Zr salts and the dicarboxylic linkers, in the presence of a small amount of acetic acid and water (1 mL total volume for 1 mmol of each reagent), followed by incubation at either room temperature or 120 °C. Such a simple "shake 'n bake" procedure, inspired by the solid-state reaction of inorganic materials, such as oxides, avoids the use of large amounts of solvents generally used for the syntheses of Zr-MOF. Acidity of the linkers and the amount of water are found to be crucial factors in affording materials of quality comparable to that of products obtained under solvo- or hydrothermal conditions.- Published
- 2021
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33. RAS-inhibiting biologics identify and probe druggable pockets including an SII-α3 allosteric site.
- Author
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Haza KZ, Martin HL, Rao A, Turner AL, Saunders SE, Petersen B, Tiede C, Tipping K, Tang AA, Ajayi M, Taylor T, Harvey M, Fishwick KM, Adams TL, Gaule TG, Trinh CH, Johnson M, Breeze AL, Edwards TA, McPherson MJ, and Tomlinson DC
- Subjects
- Allosteric Site, Biological Products chemistry, Humans, Neoplasms chemistry, Neoplasms enzymology, Signal Transduction, ras Proteins metabolism, Biological Products pharmacology, Cell Surface Display Techniques methods, Drug Discovery methods, Neoplasms drug therapy, ras Proteins antagonists & inhibitors
- Abstract
RAS mutations are the most common oncogenic drivers across human cancers, but there remains a paucity of clinically-validated pharmacological inhibitors of RAS, as druggable pockets have proven difficult to identify. Here, we identify two RAS-binding Affimer proteins, K3 and K6, that inhibit nucleotide exchange and downstream signaling pathways with distinct isoform and mutant profiles. Affimer K6 binds in the SI/SII pocket, whilst Affimer K3 is a non-covalent inhibitor of the SII region that reveals a conformer of wild-type RAS with a large, druggable SII/α3 pocket. Competitive NanoBRET between the RAS-binding Affimers and known RAS binding small-molecules demonstrates the potential to use Affimers as tools to identify pharmacophores. This work highlights the potential of using biologics with small interface surfaces to select unseen, druggable conformations in conjunction with pharmacophore identification for hard-to-drug proteins.
- Published
- 2021
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- View/download PDF
34. Fibrinogen interaction with complement C3: a potential therapeutic target to reduce thrombosis risk.
- Author
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King RJ, Schuett K, Tiede C, Jankowski V, John V, Trehan A, Simmons K, Ponnambalam S, Storey RF, Fishwick CWG, McPherson MJ, Tomlinson DC, and Ajjan RA
- Subjects
- Complement C3, Fibrin, Fibrinolysis, Humans, Fibrinogen, Thrombosis drug therapy, Thrombosis etiology, Thrombosis prevention & control
- Abstract
Complement C3 binds fibrinogen and compromises fibrin clot lysis thereby enhancing thrombosis risk. We investigated the role of fibrinogen-C3 interaction as a novel therapeutic target to reduce thrombosis risk by analysing: i) consistency in the fibrinolytic properties of C3, ii) binding sites between fibrinogen and C3 and iii) modulation of fibrin clot lysis by manipulating fibrinogen-C3 interactions. Purified fibrinogen and C3 from the same individuals (n=24) were used to assess inter-individual variability in the anti-fibrinolytic effects of C3. Microarray screening and molecular modelling evaluated C3 and fibrinogen interaction sites. Novel synthetic conformational proteins, termed Affimers, were used to modulate C3-fibrinogen interaction and fibrinolysis. C3 purified from patients with type 1 diabetes showed enhanced prolongation of fibrinolysis compared with healthy control protein [195±105 and 522±166 seconds, respectively (p=0.04)], with consistent effects but a wider range (5-51% and 5-18% lysis prolongation, respectively). Peptide microarray screening identified 2 potential C3-fibrinogen interactions sites within fibrinogen β chain (residues 424-433, 435-445). One fibrinogen-binding Affimer was isolated that displayed sequence identity with C3 in an exposed area of the protein. This Affimer abolished C3-induced prolongation of fibrinolysis (728±25.1 seconds to 632±23.7 seconds, p=0.005) and showed binding to fibrinogen in the same region that is involved in C3-fibrinogen interactions. Moreover, it shortened plasma clot lysis of patients with diabetes, cardiovascular disease or controls by 7-11%. C3 binds fibrinogen β-chain and disruption of fibrinogen-C3 interaction using Affimer proteins enhances fibrinolysis, which represents a potential novel target tool to reduce thrombosis in high risk individuals.
- Published
- 2021
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- View/download PDF
35. Reagentless Affimer- and antibody-based impedimetric biosensors for CEA-detection using a novel non-conducting polymer.
- Author
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Shamsuddin SH, Gibson TD, Tomlinson DC, McPherson MJ, Jayne DG, and Millner PA
- Subjects
- Electrochemical Techniques, Electrodes, Gold, Humans, Immunoassay, Limit of Detection, Polymers, Biosensing Techniques, Carcinoembryonic Antigen analysis
- Abstract
Polyoctopamine (POct), an amine-functionalised non-conducting polymer, as the transducer layer in an electrochemical biosensor, is presented. This polymer offers versatile covalent coupling either through thiol linker conjugation, carboxyl or aldehyde functional groups without the requirement of pre- or post-surface activation. The colorectal cancer biomarker carcinoembryonic antigen (CEA) was selected as the target analyte, whilst an antibody and a synthetic binding protein, an Affimer, were used as distinct bioreceptors to demonstrate the versatility of polyoctopamine as a transducer polymer layer for oriented immobilisation of the bioreceptors. The electrodeposited polymer layer was characterised using cyclic voltammetry, electrochemical impedance spectroscopy, and on-sensor chemiluminescent blotting. The performance of optimised POct-based biosensors were tested in spiked human serum. Results showed that the electropolymerisation of octopamine on screen printed gold electrode generates a thin polymer film with low resistance. Close proximity of the immobilised bioreceptors to the transducer layer greatly enhanced the sensitivity detection. The sensitivity of the smaller monomeric bioreceptor (Affimer, 12.6 kDa) to detect CEA was comparable to the dimeric antibody (150 kDa) with limit of detection at 11.76 fM which is significantly lower than the basal clinical levels of 25 pM. However, the Affimer-based sensor had a narrower dynamic range compared to the immunosensor (1-100 fM vs. 1 fM - 100 nM, respectively). All electrochemical measurements were done in less than 5 min with small sample volumes (10 μl). Hence, polyoctopamine features a simple fabrication of impedimetric biosensors using amine-functionalisation technique, provides rapid response time with enhanced sensitivity and label-free detection., (Crown Copyright © 2021. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
36. Selection and characterisation of Affimers specific for CEA recognition.
- Author
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Shamsuddin SH, Jayne DG, Tomlinson DC, McPherson MJ, and Millner PA
- Subjects
- Carcinoembryonic Antigen chemistry, Cystatin A chemistry, Epitopes chemistry, GPI-Linked Proteins chemistry, GPI-Linked Proteins metabolism, Humans, Protein Binding, Biosensing Techniques methods, Carcinoembryonic Antigen metabolism, Chromatography, Affinity methods, Cystatin A isolation & purification, Cystatin A metabolism, Epitopes metabolism, Peptide Library
- Abstract
Carcinoembryonic antigen (CEA) is the only blood based protein biomarker at present, used for preoperative screening of advanced colorectal cancer (CRC) patients to determine the appropriate curative treatments and post-surveillance screening for tumour recurrence. Current diagnostics for CRC detection have several limitations and development of a highly sensitive, specific and rapid diagnostic device is required. The majority of such devices developed to date are antibody-based and suffer from shortcomings including multimeric binding, cost and difficulties in mass production. To circumvent antibody-derived limitations, the present study focused on the development of Affimer proteins as a novel alternative binding reagent for CEA detection. Here, we describe the selection, from a phage display library, of Affimers specific to CEA protein. Characterization of three anti-CEA Affimers reveal that these bind specifically and selectively to protein epitopes of CEA from cell culture lysate and on fixed cells. Kinetic binding analysis by SPR show that the Affimers bind to CEA with high affinity and within the nM range. Therefore, they have substantial potential for used as novel affinity reagents in diagnostic imaging, targeted CRC therapy, affinity purification and biosensor applications.
- Published
- 2021
- Full Text
- View/download PDF
37. Isolation of Artificial Binding Proteins (Affimer Reagents) for Use in Molecular and Cellular Biology.
- Author
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Tang AAS, Tiede C, McPherson MJ, and Tomlinson DC
- Subjects
- Antibodies metabolism, Carrier Proteins chemistry, Cell Surface Display Techniques, Cytological Techniques, Enzyme-Linked Immunosorbent Assay, Humans, Peptide Library, Protein Binding, Structure-Activity Relationship, Carrier Proteins isolation & purification, Cell Biology, Indicators and Reagents, Molecular Biology methods
- Abstract
Artificial binding proteins have been validated as alternatives to antibodies in their use as research reagents in molecular and cellular biology. For example, they have been used as inhibitors of protein-protein interactions to modulate activity, to facilitate crystallization, and as probes for cellular imaging.Phage display is a widely used approach for isolating target-specific binding reagents, and it has even been used to isolate isoform-specific binding proteins and binders that can distinguish between highly homologous protein domains.Here, we describe methods that have been employed in isolating highly specific artificial binding proteins against a wide range of target proteins.
- Published
- 2021
- Full Text
- View/download PDF
38. Time-dependent discrimination advantages for harmonic sounds suggest efficient coding for memory.
- Author
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McPherson MJ and McDermott JH
- Subjects
- Acoustic Stimulation methods, Adolescent, Adult, Female, Humans, Male, Middle Aged, Psychoacoustics, Sound, Time Factors, Young Adult, Auditory Threshold physiology, Memory physiology, Music psychology
- Abstract
Perceptual systems have finite memory resources and must store incoming signals in compressed formats. To explore whether representations of a sound's pitch might derive from this need for compression, we compared discrimination of harmonic and inharmonic sounds across delays. In contrast to inharmonic spectra, harmonic spectra can be summarized, and thus compressed, using their fundamental frequency (f0). Participants heard two sounds and judged which was higher. Despite being comparable for sounds presented back-to-back, discrimination was better for harmonic than inharmonic stimuli when sounds were separated in time, implicating memory representations unique to harmonic sounds. Patterns of individual differences (correlations between thresholds in different conditions) indicated that listeners use different representations depending on the time delay between sounds, directly comparing the spectra of temporally adjacent sounds, but transitioning to comparing f0s across delays. The need to store sound in memory appears to determine reliance on f0-based pitch and may explain its importance in music, in which listeners must extract relationships between notes separated in time., Competing Interests: The authors declare no competing interest.
- Published
- 2020
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39. Perceptual fusion of musical notes by native Amazonians suggests universal representations of musical intervals.
- Author
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McPherson MJ, Dolan SE, Durango A, Ossandon T, Valdés J, Undurraga EA, Jacoby N, Godoy RA, and McDermott JH
- Subjects
- Acoustic Stimulation, Adult, Bolivia, Female, Humans, Male, Sound, Indigenous Peoples, Music, Pitch Perception physiology
- Abstract
Music perception is plausibly constrained by universal perceptual mechanisms adapted to natural sounds. Such constraints could arise from our dependence on harmonic frequency spectra for segregating concurrent sounds, but evidence has been circumstantial. We measured the extent to which concurrent musical notes are misperceived as a single sound, testing Westerners as well as native Amazonians with limited exposure to Western music. Both groups were more likely to mistake note combinations related by simple integer ratios as single sounds ('fusion'). Thus, even with little exposure to Western harmony, acoustic constraints on sound segregation appear to induce perceptual structure on note combinations. However, fusion did not predict aesthetic judgments of intervals in Westerners, or in Amazonians, who were indifferent to consonance/dissonance. The results suggest universal perceptual mechanisms that could help explain cross-cultural regularities in musical systems, but indicate that these mechanisms interact with culture-specific influences to produce musical phenomena such as consonance.
- Published
- 2020
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40. C-Terminal Domain of the Human Zinc Transporter hZnT8 Is Structurally Indistinguishable from Its Disease Risk Variant (R325W).
- Author
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Ullah R, Shehzad A, Shah MA, March M, Ismat F, Iqbal M, Onesti S, Rahman M, and McPherson MJ
- Subjects
- Arginine metabolism, Crystallography, X-Ray, Humans, Models, Molecular, Protein Domains, Protein Multimerization, Protein Structure, Secondary, Scattering, Small Angle, Tryptophan metabolism, X-Ray Diffraction, Zinc Transporter 8 genetics, Amino Acid Substitution, Diabetes Mellitus, Type 2 genetics, Zinc metabolism, Zinc Transporter 8 chemistry, Zinc Transporter 8 metabolism
- Abstract
The human zinc transporter 8 (hZnT8) plays important roles in the storage of insulin in the secretory vesicles of pancreatic β cells. hZnT8 consists of a transmembrane domain, with its N- and C-termini protruding into the cytoplasm. Interestingly, the exchange of arginine to tryptophan at position 325 in the C-terminal domain (CTD) increases the risk of developing type 2 diabetes mellitus (T2D). In the present study, the CTDs of hZnT8 (the wild-type (WT) and its disease risk variant (R325W)) were expressed, purified, and characterized in their native forms by biophysical techniques. The data reveal that the CTDs form tetramers which are stabilized by zinc binding, and exhibit negligible differences in their secondary structure content and zinc-binding affinities in solution. These findings provide the basis for conducting further structural studies aimed at unravelling the molecular mechanism underlying the increased susceptibility to develop T2D, which is modulated by the disease risk variant.
- Published
- 2020
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- View/download PDF
41. Pushing the Envelope: Advancement of ADCs Outside of Oncology.
- Author
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McPherson MJ and Hobson AD
- Subjects
- Animals, Antibodies, Monoclonal chemistry, Antibodies, Monoclonal immunology, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Biomarkers, Humans, Immunoconjugates therapeutic use, Molecular Targeted Therapy, Structure-Activity Relationship, Drug Development, Immunoconjugates chemistry, Immunoconjugates pharmacology
- Abstract
The majority of ADCs in preclinical and clinical development are for oncology indications where cytotoxic payloads are targeted to antigen-expressing cancer cells. However, the modulation of pathogenic cellular activity via ADC-mediated delivery of bioactive small molecules is also an attractive concept for non-oncology indications leading to an expanded application of the technology. Here we summarize those ADCs that have been described so far for non-oncology applications and which cover a variety of payload mechanisms beyond cell killing, from early in vitro proof-of-concept experiments to clinical trials. As our understanding of ADC technology continues to grow, it is anticipated that the development of ADCs as therapeutics for disease areas outside of oncology will also increase.
- Published
- 2020
- Full Text
- View/download PDF
42. Affimers as anti-idiotypic affinity reagents for pharmacokinetic analysis of biotherapeutics.
- Author
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Adamson H, Nicholl A, Tiede C, Tang AA, Davidson A, Curd H, Wignall A, Ford R, Nuttall J, McPherson MJ, Johnson M, and Tomlinson DC
- Subjects
- Animals, Humans, Antibodies, Monoclonal pharmacokinetics, Antibody Affinity drug effects, Biological Therapy methods
- Abstract
Therapeutic antibodies are the fastest growing class of drugs in the treatment of cancer, and autoimmune and inflammatory diseases that require the concomitant development of assays to monitor therapeutic antibody levels. Here, we demonstrate that the use of Affimer nonantibody binding proteins provides an advantage over current antibody-based detection systems. For four therapeutic antibodies, we used phage display to isolate highly specific anti-idiotypic Affimer reagents, which selectively bind to the therapeutic antibody idiotype. For each antibody target the calibration curves met US Food and Drug Administration criteria and the dynamic range compared favorably with commercially available reagents. Affimer proteins therefore represent promising anti-idiotypic reagents that are simple to select and manufacture, and that offer the sensitivity, specificity and consistency required for pharmacokinetic assays.
- Published
- 2019
- Full Text
- View/download PDF
43. Affimer-Enzyme-Inhibitor Switch Sensor for Rapid Wash-free Assays of Multimeric Proteins.
- Author
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Adamson H, Ajayi MO, Campbell E, Brachi E, Tiede C, Tang AA, Adams TL, Ford R, Davidson A, Johnson M, McPherson MJ, Tomlinson DC, and Jeuken LJC
- Subjects
- Enzyme Inhibitors pharmacology, Humans, beta-Lactamases metabolism, Biosensing Techniques, Enzyme Inhibitors chemistry, Enzyme-Linked Immunosorbent Assay, beta-Lactamases analysis
- Abstract
Robust technology is required to underpin rapid point-of-care and in-field diagnostics to improve timely decision making across broad sectors. An attractive strategy combines target recognition and signal generating elements into an "active" enzyme-switch that directly transduces target-binding into a signal. However, approaches that are broadly applicable to diverse targets remain elusive. Here, an enzyme-inhibitor switch sensor was developed by insertion of non-immunoglobulin Affimer binding proteins, between TEM1-β-lactamase and its inhibitor protein, such that target binding disrupts the enzyme-inhibitor complex. Design principles for a successful switch architecture are illustrated by the rapid (min), simple (wash-free), and sensitive (pM) quantification of multimeric target analytes in biological samples (serum, plasma, leaf extracts), across three application areas. A therapeutic antibody (Herceptin), protein biomarker (human C-reactive protein), and plant virus (cow pea mosaic virus) were targeted, demonstrating assays for therapeutic drug monitoring, health diagnostics, and plant pathogen detection, respectively. Batch-to-batch reproducibility, shelf-life stability, and consistency with validated enzyme-linked immunosorbent assay analysis confirm that the principle of an Affimer-enzyme-inhibitor switch provides a platform for point-of-care and in-field diagnostics.
- Published
- 2019
- Full Text
- View/download PDF
44. Universal and Non-universal Features of Musical Pitch Perception Revealed by Singing.
- Author
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Jacoby N, Undurraga EA, McPherson MJ, Valdés J, Ossandón T, and McDermott JH
- Subjects
- Adult, Aged, Bolivia, Boston, Female, Humans, Indians, South American, Male, Middle Aged, New York City, Young Adult, Pitch Perception, Singing
- Abstract
Musical pitch perception is argued to result from nonmusical biological constraints and thus to have similar characteristics across cultures, but its universality remains unclear. We probed pitch representations in residents of the Bolivian Amazon-the Tsimane', who live in relative isolation from Western culture-as well as US musicians and non-musicians. Participants sang back tone sequences presented in different frequency ranges. Sung responses of Amazonian and US participants approximately replicated heard intervals on a logarithmic scale, even for tones outside the singing range. Moreover, Amazonian and US reproductions both deteriorated for high-frequency tones even though they were fully audible. But whereas US participants tended to reproduce notes an integer number of octaves above or below the heard tones, Amazonians did not, ignoring the note "chroma" (C, D, etc.). Chroma matching in US participants was more pronounced in US musicians than non-musicians, was not affected by feedback, and was correlated with similarity-based measures of octave equivalence as well as the ability to match the absolute f0 of a stimulus in the singing range. The results suggest the cross-cultural presence of logarithmic scales for pitch, and biological constraints on the limits of pitch, but indicate that octave equivalence may be culturally contingent, plausibly dependent on pitch representations that develop from experience with particular musical systems. VIDEO ABSTRACT., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
45. 13 C pNMR of "crumple zone" Cu(II) isophthalate metal-organic frameworks.
- Author
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Dawson DM, Sansome CEF, McHugh LN, McPherson MJ, McCormick McPherson LJ, Morris RE, and Ashbrook SE
- Abstract
NMR spectroscopy of paramagnetic materials (pNMR) has the potential to provide great structural insight, but many challenges remain in interpreting the spectra in detail. This work presents a study of a series of structurally analogous metal-organic frameworks (MOFs) based on 5-substituted isophthalate linkers and Cu(II) paddlewheel dimers, of interest owing to their "crumple zone" structural rearrangement on dehydration/rehydration.
13 C MAS NMR spectra reveal a wide variation in the observed resonance position for chemically similar C species in the different MOFs but, despite this, resonances are overlapped in several cases. However, by considering a combination of the integration of quantitative spectra, the resonance position as a function of temperature and T1 relaxation measurements, the spectra can be fully assigned. It is also demonstrated that the prototypical MOF in this series, STAM-1, displays a crumple zone rearrangement on dehydration, similar to the well-characterised 5-ethoxyisophthalate MOF (STAM-17-OEt) although, while the materials have similar local C environments, dehydrated STAM-1 exhibits less long-range order., (Copyright © 2019 Elsevier Inc. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
46. Affimer reagents as tools in diagnosing plant virus diseases.
- Author
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Hesketh EL, Tiede C, Adamson H, Adams TL, Byrne MJ, Meshcheriakova Y, Kruse I, McPherson MJ, Lomonossoff GP, Tomlinson DC, and Ranson NA
- Subjects
- Antigens, Viral, Comovirus immunology, Comovirus ultrastructure, Crop Protection, Crops, Agricultural virology, Cross Reactions, Cryoelectron Microscopy, Food Supply, Indicators and Reagents, Plant Viruses pathogenicity, Plant Viruses ultrastructure, Virion immunology, Virion ultrastructure, Plant Diseases virology, Plant Viruses isolation & purification
- Abstract
Plant viruses can cause devastating losses to agriculture and are therefore a major threat to food security. The rapid identification of virally-infected crops allowing containment is essential to limit such threats, but plant viral diseases can be extremely challenging to diagnose. An ideal method for plant virus diagnosis would be a device which can be implemented easily in the field. Such devices require a binding reagent that is specific for the virus of interest. We chose to investigate the use of Affimer reagents, artificial binding proteins and a model plant virus Cowpea Mosaic virus (CPMV) empty virus like particles (eVLPs). CPMV-eVLP mimic the morphology of wild-type (WT) CPMV but lack any infectious genomic material and so do not have biocontainment issues. We have produced and purified an Affimer reagent selected for its ability to bind to CPMV-eVLP and have shown that the selected Affimer also specifically binds to WT CPMV. We have produced a 3.4 Å structure of WT CPMV bound to the Affimer using cryo-electron microscopy. Finally, we have shown that this Affimer is capable of reliably detecting the virus in crude extracts of CPMV-infected leaves and can therefore form the basis for the future development of diagnostic tests.
- Published
- 2019
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- View/download PDF
47. Affimer proteins as a tool to modulate fibrinolysis, stabilize the blood clot, and reduce bleeding complications.
- Author
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Kearney KJ, Pechlivani N, King R, Tiede C, Phoenix F, Cheah R, Macrae FL, Simmons KJ, Manfield IW, Smith KA, Spurgeon BEJ, Naseem KM, Ariens RAS, McPherson MJ, Tomlinson DC, and Ajjan RA
- Subjects
- Humans, Thrombosis etiology, Tissue Plasminogen Activator metabolism, Blood Proteins pharmacology, Fibrin Clot Lysis Time, Fibrinogen metabolism, Fibrinolysis drug effects, Thrombosis prevention & control
- Abstract
Bleeding complications secondary to surgery, trauma, or coagulation disorders are important causes of morbidity and mortality. Although fibrin sealants are considered to minimize blood loss, this is not widely adopted because of its high cost and/or risk for infection. We present a novel methodology employing nonantibody fibrinogen-binding proteins, termed Affimers, to stabilize fibrin networks with the potential to control excessive bleeding. Two fibrinogen-specific Affimer proteins, F5 and G2, were identified and characterized for their effects on clot structure/fibrinolysis, using turbidimetric and permeation analyses and confocal and electron microscopy. Binding studies and molecular modeling identified interaction sites, whereas plasmin generation assays determined effects on plasminogen activation. In human plasma, F5 and G2 prolonged clot lysis time from 9.8 ± 1.1 minutes in the absence of Affimers to 172.6 ± 7.4 and more than 180 minutes ( P < .0001), respectively, and from 7.6 ± 0.2 to 28.7 ± 5.8 ( P < .05) and 149.3 ± 9.7 ( P < .0001) minutes in clots made from purified fibrinogen. Prolongation in fibrinolysis was consistent across plasma samples from healthy control patients and individuals at high bleeding risk. F5 and G2 had a differential effect on clot structure and G2 profoundly altered fibrin fiber arrangement, whereas F5 maintained physiological clot structure. Affimer F5 reduced fibrin-dependent plasmin generation and was predicted to bind fibrinogen D fragment close to tissue plasminogen activator (tPA; residues γ312-324) and plasminogen (α148-160) binding sites, thus interfering with tPA-plasminogen interaction and representing 1 potential mechanism for modulation of fibrinolysis. Our Affimer proteins provide a novel methodology for stabilizing fibrin networks with potential future clinical implications to reduce bleeding risk., (© 2019 by The American Society of Hematology.)
- Published
- 2019
- Full Text
- View/download PDF
48. Hydrolytic stability in hemilabile metal-organic frameworks.
- Author
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McHugh LN, McPherson MJ, McCormick LJ, Morris SA, Wheatley PS, Teat SJ, McKay D, Dawson DM, Sansome CEF, Ashbrook SE, Stone CA, Smith MW, and Morris RE
- Abstract
Highly porous metal-organic frameworks (MOFs), which have undergone exciting developments over the past few decades, show promise for a wide range of applications. However, many studies indicate that they suffer from significant stability issues, especially with respect to their interactions with water, which severely limits their practical potential. Here we demonstrate how the presence of 'sacrificial' bonds in the coordination environment of its metal centres (referred to as hemilability) endows a dehydrated copper-based MOF with good hydrolytic stability. On exposure to water, in contrast to the indiscriminate breaking of coordination bonds that typically results in structure degradation, it is non-structural weak interactions between the MOF's copper paddlewheel clusters that are broken and the framework recovers its as-synthesized, hydrated structure. This MOF retained its structural integrity even after contact with water for one year, whereas HKUST-1, a compositionally similar material that lacks these sacrificial bonds, loses its crystallinity in less than a day under the same conditions.
- Published
- 2018
- Full Text
- View/download PDF
49. Non-immunoglobulin scaffold proteins: Precision tools for studying protein-protein interactions in cancer.
- Author
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Martin HL, Bedford R, Heseltine SJ, Tang AA, Haza KZ, Rao A, McPherson MJ, and Tomlinson DC
- Subjects
- Humans, Neoplasm Proteins metabolism, Neoplasms chemistry, Protein Binding, Neoplasm Proteins chemistry, Neoplasms metabolism
- Abstract
Cancer is frequently characterised by dysregulation of the cellular signalling processes that govern proliferation, survival and attachment. Understanding such dysregulation continues to present a challenge given the importance of protein-protein interactions in intracellular processes. Exploring this protein-protein interactome requires novel tools capable of discriminating between highly homologous proteins, individual domains and post-translational modifications. This review examines the potential of scaffold-based binding proteins to fulfil these requirements. It also explores protein-protein interactions in the context of intracellular signalling pathways and cancer, and demonstrates the uses of scaffold proteins as functional moderators, biosensors and imaging reagents. This review also highlights the timeliness and potential to develop international consortia to develop and validate highly specific "proteome" scaffold-based binding protein reagents with the ultimate aim of developing screening tools for studying the interactome., (Copyright © 2018. Published by Elsevier B.V.)
- Published
- 2018
- Full Text
- View/download PDF
50. Identification of the site of oxidase substrate binding in Scytalidium thermophilum catalase.
- Author
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Yuzugullu Karakus Y, Goc G, Balci S, Yorke BA, Trinh CH, McPherson MJ, and Pearson AR
- Subjects
- Amitrole metabolism, Catalase antagonists & inhibitors, Catalytic Domain, Crystallography, X-Ray, Heme analogs & derivatives, Heme metabolism, NADP metabolism, Oxidoreductases metabolism, Binding Sites, Catalase chemistry, Fungal Proteins chemistry, Fungi enzymology
- Abstract
The catalase from Scytalidium thermophilum is a homotetramer containing a heme d in each active site. Although the enzyme has a classical monofunctional catalase fold, it also possesses oxidase activity towards a number of small organics, including catechol and phenol. In order to further investigate this, the crystal structure of the complex of the catalase with the classical catalase inhibitor 3-amino-1,2,4-triazole (3TR) was determined at 1.95 Å resolution. Surprisingly, no binding to the heme site was observed; instead, 3TR occupies a binding site corresponding to the NADPH-binding pocket in mammalian catalases at the entrance to a lateral channel leading to the heme. Kinetic analysis of site-directed mutants supports the assignment of this pocket as the binding site for oxidase substrates., (open access.)
- Published
- 2018
- Full Text
- View/download PDF
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