1
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Moiseenko A, Zhang Y, Vorovitch MF, Ivanova AL, Liu Z, Osolodkin DI, Egorov AM, Ishmukhametov AA, Sokolova OS. Structural diversity of tick-borne encephalitis virus particles in the inactivated vaccine based on strain Sofjin. Emerg Microbes Infect 2024; 13:2290833. [PMID: 38073510 DOI: 10.1080/22221751.2023.2290833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 11/29/2023] [Indexed: 03/12/2024]
Abstract
The main approach to preventing tick-borne encephalitis (TBE) is vaccination. Formaldehyde-inactivated TBE vaccines have a proven record of safety and efficiency but have never been characterized structurally with atomic resolution. We report a cryoelectron microscopy (cryo-EM) structure of the formaldehyde-inactivated TBE virus (TBEV) of Sofjin-Chumakov strain representing the Far-Eastern subtype. A 3.8 Å resolution reconstruction reveals the structural integrity of the envelope E proteins, specifically the E protein ectodomains. The comparative study shows a high structural similarity to the previously published structures of the TBEV European subtype strains Hypr and Kuutsalo-14. A fraction of inactivated virions exhibits asymmetric features including the deformations of the membrane profile. We propose that the heterogeneity is caused by inactivation and perform a local variability analysis on the small parts of the envelope protein shell to reveal membrane curvature features possibly induced by the inactivation. The results of this study will have implications for the design of novel vaccines against diseases caused by flaviviruses.
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Affiliation(s)
- Andrey Moiseenko
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Yichen Zhang
- Faculty of Biology, Shenzhen MSU-BIT University, Shenzhen, People's Republic of China
| | - Mikhail F Vorovitch
- FSASI "Chumakov FSC R&D IBP RAS" (Institute of Poliomyelitis), Moscow, Russia
- Sechenov First Moscow State Medical University, Moscow, Russia
| | - Alla L Ivanova
- FSASI "Chumakov FSC R&D IBP RAS" (Institute of Poliomyelitis), Moscow, Russia
| | - Zheng Liu
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, Chinese University of Hong Kong, Shenzhen, People's Republic of China
| | - Dmitry I Osolodkin
- FSASI "Chumakov FSC R&D IBP RAS" (Institute of Poliomyelitis), Moscow, Russia
- Sechenov First Moscow State Medical University, Moscow, Russia
| | - Alexey M Egorov
- FSASI "Chumakov FSC R&D IBP RAS" (Institute of Poliomyelitis), Moscow, Russia
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
| | - Aydar A Ishmukhametov
- FSASI "Chumakov FSC R&D IBP RAS" (Institute of Poliomyelitis), Moscow, Russia
- Sechenov First Moscow State Medical University, Moscow, Russia
| | - Olga S Sokolova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
- Faculty of Biology, Shenzhen MSU-BIT University, Shenzhen, People's Republic of China
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2
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Aleksic M, Meng X. Protein Haptenation and Its Role in Allergy. Chem Res Toxicol 2024; 37:850-872. [PMID: 38834188 PMCID: PMC11187640 DOI: 10.1021/acs.chemrestox.4c00062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/14/2024] [Accepted: 05/21/2024] [Indexed: 06/06/2024]
Abstract
Humans are exposed to numerous electrophilic chemicals either as medicines, in the workplace, in nature, or through use of many common cosmetic and household products. Covalent modification of human proteins by such chemicals, or protein haptenation, is a common occurrence in cells and may result in generation of antigenic species, leading to development of hypersensitivity reactions. Ranging in severity of symptoms from local cutaneous reactions and rhinitis to potentially life-threatening anaphylaxis and severe hypersensitivity reactions such as Stephen-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), all these reactions have the same Molecular Initiating Event (MIE), i.e. haptenation. However, not all individuals who are exposed to electrophilic chemicals develop symptoms of hypersensitivity. In the present review, we examine common chemistry behind the haptenation reactions leading to formation of neoantigens. We explore simple reactions involving single molecule additions to a nucleophilic side chain of proteins and complex reactions involving multiple electrophilic centers on a single molecule or involving more than one electrophilic molecule as well as the generation of reactive molecules from the interaction with cellular detoxification mechanisms. Besides generation of antigenic species and enabling activation of the immune system, we explore additional events which result directly from the presence of electrophilic chemicals in cells, including activation of key defense mechanisms and immediate consequences of those reactions, and explore their potential effects. We discuss the factors that work in concert with haptenation leading to the development of hypersensitivity reactions and those that may act to prevent it from developing. We also review the potential harnessing of the specificity of haptenation in the design of potent covalent therapeutic inhibitors.
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Affiliation(s)
- Maja Aleksic
- Safety
and Environmental Assurance Centre, Unilever,
Colworth Science Park, Sharnbrook, Bedford MK44
1LQ, U.K.
| | - Xiaoli Meng
- MRC
Centre for Drug Safety Science, Department of Molecular and Clinical
Pharmacology, The University of Liverpool, Liverpool L69 3GE, U.K.
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3
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Aleksic M, Rajagopal R, de-Ávila R, Spriggs S, Gilmour N. The skin sensitization adverse outcome pathway: exploring the role of mechanistic understanding for higher tier risk assessment. Crit Rev Toxicol 2024; 54:69-91. [PMID: 38385441 DOI: 10.1080/10408444.2024.2308816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 12/19/2023] [Indexed: 02/23/2024]
Abstract
For over a decade, the skin sensitization Adverse Outcome Pathway (AOP) has served as a useful framework for development of novel in chemico and in vitro assays for use in skin sensitization hazard and risk assessment. Since its establishment, the AOP framework further fueled the existing efforts in new assay development and stimulated a plethora of activities with particular focus on validation, reproducibility and interpretation of individual assays and combination of assay outputs for use in hazard/risk assessment. In parallel, research efforts have also accelerated in pace, providing new molecular and dynamic insight into key events leading to sensitization. In light of novel hypotheses emerging from over a decade of focused research effort, mechanistic evidence relating to the key events in the skin sensitization AOP may complement the tools currently used in risk assessment. We reviewed the recent advances unraveling the complexity of molecular events in sensitization and signpost the most promising avenues for further exploration and development of useful assays.
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Affiliation(s)
- Maja Aleksic
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, UK
| | - Ramya Rajagopal
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, UK
| | - Renato de-Ávila
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, UK
| | - Sandrine Spriggs
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, UK
| | - Nicola Gilmour
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, UK
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4
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Röth D, Molina-Franky J, Williams JC, Kalkum M. Mass Spectrometric Detection of Formaldehyde-Crosslinked PBMC Proteins in Cell-Free DNA Blood Collection Tubes. Molecules 2023; 28:7880. [PMID: 38067609 PMCID: PMC10708122 DOI: 10.3390/molecules28237880] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 11/27/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
Streck tubes are commonly used to collect blood samples to preserve cell-free circulating DNA. They contain imidazolidinyl urea as a formaldehyde-releasing agent to stabilize cells. We investigated whether the released formaldehyde leads to crosslinking of intracellular proteins. Therefore, we employed a shotgun proteomics experiment on human peripheral blood mononuclear cells (PBMCs) that were isolated from blood collected in Streck tubes, EDTA tubes, EDTA tubes containing formaldehyde, or EDTA tubes containing allantoin. The identified crosslinks were validated in parallel reaction monitoring LC/MS experiments. In total, we identified and validated 45 formaldehyde crosslinks in PBMCs from Streck tubes, which were also found in PBMCs from formaldehyde-treated blood, but not in EDTA- or allantoin-treated samples. Most were derived from cytoskeletal proteins and histones, indicating the ability of Streck tubes to fix cells. In addition, we confirm a previous observation that formaldehyde crosslinking of proteins induces a +24 Da mass shift more frequently than a +12 Da shift. The crosslinking capacity of Streck tubes needs to be considered when selecting blood-collection tubes for mass-spectrometry-based proteomics or metabolomic experiments.
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Affiliation(s)
- Daniel Röth
- Department of Immunology and Theranostics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA (J.M.-F.)
| | - Jessica Molina-Franky
- Department of Immunology and Theranostics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA (J.M.-F.)
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá 112111, Colombia
- Biotechnology Institute Department, Faculty of Sciences, Universidad Nacional de Colombia, Bogotá 111321, Colombia
| | - John C. Williams
- Department of Cancer Biology and Molecular Medicine, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | - Markus Kalkum
- Department of Immunology and Theranostics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA (J.M.-F.)
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5
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Emms VL, Lewis LA, Beja L, Bulman NFA, Pires E, Muskett FW, McCullagh JSO, Swift LP, McHugh PJ, Hopkinson RJ. N-Acyloxymethyl-phthalimides deliver genotoxic formaldehyde to human cells. Chem Sci 2023; 14:12498-12505. [PMID: 38020377 PMCID: PMC10646869 DOI: 10.1039/d3sc02867d] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 09/13/2023] [Indexed: 12/01/2023] Open
Abstract
Formaldehyde is a pollutant and human metabolite that is toxic at high concentrations. Biological studies on formaldehyde are hindered by its high reactivity and volatility, which make it challenging to deliver quantitatively to cells. Here, we describe the development and validation of a set of N-acyloxymethyl-phthalimides as cell-relevant formaldehyde delivery agents. These esterase-sensitive compounds were similarly or less inhibitory to human cancer cell growth than free formaldehyde but the lead compound increased intracellular formaldehyde concentrations, increased cellular levels of thymidine derivatives (implying increased formaldehyde-mediated carbon metabolism), induced formation of cellular DNA-protein cross-links and induced cell death in pancreatic cancer cells. Overall, our N-acyloxymethyl-phthalimides and control compounds provide an accessible and broadly applicable chemical toolkit for formaldehyde biological research and have potential as cancer therapeutics.
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Affiliation(s)
- Vicki L Emms
- Institute for Structural and Chemical Biology, School of Chemistry, University of Leicester Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
| | - Liam A Lewis
- Institute for Structural and Chemical Biology, School of Chemistry, University of Leicester Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
| | - Lilla Beja
- Institute for Structural and Chemical Biology, School of Chemistry, University of Leicester Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
| | - Natasha F A Bulman
- Institute for Structural and Chemical Biology, School of Chemistry, University of Leicester Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
| | - Elisabete Pires
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Frederick W Muskett
- Institute for Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
| | - James S O McCullagh
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory 12 Mansfield Road Oxford OX1 3TA UK
| | - Lonnie P Swift
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital Headington Oxford OX3 9DS UK
| | - Peter J McHugh
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital Headington Oxford OX3 9DS UK
| | - Richard J Hopkinson
- Institute for Structural and Chemical Biology, School of Chemistry, University of Leicester Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
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6
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Barman P, Kaja A, Chakraborty P, Bhaumik SR. Chromatin and non-chromatin immunoprecipitations to capture protein-protein and protein-nucleic acid interactions in living cells. Methods 2023; 218:158-166. [PMID: 37611837 PMCID: PMC10528071 DOI: 10.1016/j.ymeth.2023.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/18/2023] [Accepted: 08/19/2023] [Indexed: 08/25/2023] Open
Abstract
Proteins are expressed from genes via sequential biological processes of transcription, mRNA processing, export and translation, and play their roles in maintaining cellular functions via interactions with proteins, DNAs or RNAs. Thus, it is important to study the protein interactions during biological processes in living cells towards understanding their mechanisms-of-action in real time. Methodologies have been developed over the years to study protein interactions in vivo. One state-of-the-art approach is formaldehyde crosslinking-based immuno- or chemi-precipitation to analyze selective as well as genome/proteome-wide interactions in living cells. It is a popular and widely used methodology for cellular analysis of the protein-protein and protein-nucleic acid interactions. Here, we describe this approach to analyze protein-protein/nucleic acid interactions in vivo.
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Affiliation(s)
- Priyanka Barman
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Amala Kaja
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Pritam Chakraborty
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Sukesh R Bhaumik
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA.
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7
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Veenstra BT, Veenstra TD. Proteomic applications in identifying protein-protein interactions. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 138:1-48. [PMID: 38220421 DOI: 10.1016/bs.apcsb.2023.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
There are many things that can be used to characterize a protein. Size, isoelectric point, hydrophobicity, structure (primary to quaternary), and subcellular location are just a few parameters that are used. The most important feature of a protein, however, is its function. While there are many experiments that can indicate a protein's role, identifying the molecules it interacts with is probably the most definitive way of determining its function. Owing to technology limitations, protein interactions have historically been identified on a one molecule per experiment basis. The advent of high throughput multiplexed proteomic technologies in the 1990s, however, made identifying hundreds and thousands of proteins interactions within single experiments feasible. These proteomic technologies have dramatically increased the rate at which protein-protein interactions (PPIs) are discovered. While the improvement in mass spectrometry technology was an early driving force in the rapid pace of identifying PPIs, advances in sample preparation and chromatography have recently been propelling the field. In this chapter, we will discuss the importance of identifying PPIs and describe current state-of-the-art technologies that demonstrate what is currently possible in this important area of biological research.
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Affiliation(s)
- Benjamin T Veenstra
- Department of Math and Sciences, Cedarville University, Cedarville, OH, United States
| | - Timothy D Veenstra
- School of Pharmacy, Cedarville University, Cedarville, OH, United States.
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8
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John T, Pires E, Hester SS, Salah E, Hopkinson RJ, Schofield CJ. Formaldehyde reacts with N-terminal proline residues to give bicyclic aminals. Commun Chem 2023; 6:12. [PMID: 36698022 PMCID: PMC9839752 DOI: 10.1038/s42004-022-00801-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 12/20/2022] [Indexed: 01/15/2023] Open
Abstract
Formaldehyde (HCHO) is a potent electrophile that is toxic above threshold levels, but which is also produced in the nuclei of eukaryotic cells by demethylases. We report studies with the four canonical human histones revealing that histone H2B reacts with HCHO, including as generated by a histone demethylase, to give a stable product. NMR studies show that HCHO reacts with the N-terminal proline and associated amide of H2B to give a 5,5-bicyclic aminal that is relatively stable to competition with HCHO scavengers. While the roles of histone modification by this reaction require further investigation, we demonstrated the potential of N-terminal aminal formation to modulate protein function by conducting biochemical and cellular studies on the effects of HCHO on catalysis by 4-oxalocrotonate tautomerase, which employs a nucleophilic N-terminal proline. The results suggest that reactions of N-terminal residues with HCHO and other aldehydes have potential to alter protein function.
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Affiliation(s)
- Tobias John
- Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Elisabete Pires
- Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Svenja S Hester
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, UK
| | - Eidarus Salah
- Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Richard J Hopkinson
- Leicester Institute for Structural and Chemical Biology and School of Chemistry, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester, LE1 7RH, UK.
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9
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Obi EN, Tellock DA, Thomas GJ, Veenstra TD. Biomarker Analysis of Formalin-Fixed Paraffin-Embedded Clinical Tissues Using Proteomics. Biomolecules 2023; 13:biom13010096. [PMID: 36671481 PMCID: PMC9855471 DOI: 10.3390/biom13010096] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 01/06/2023] Open
Abstract
The relatively recent developments in mass spectrometry (MS) have provided novel opportunities for this technology to impact modern medicine. One of those opportunities is in biomarker discovery and diagnostics. Key developments in sample preparation have enabled a greater range of clinical samples to be characterized at a deeper level using MS. While most of these developments have focused on blood, tissues have also been an important resource. Fresh tissues, however, are difficult to obtain for research purposes and require significant resources for long-term storage. There are millions of archived formalin-fixed paraffin-embedded (FFPE) tissues within pathology departments worldwide representing every possible tissue type including tumors that are rare or very small. Owing to the chemical technique used to preserve FFPE tissues, they were considered intractable to many newer proteomics techniques and primarily only useful for immunohistochemistry. In the past couple of decades, however, researchers have been able to develop methods to extract proteins from FFPE tissues in a form making them analyzable using state-of-the-art technologies such as MS and protein arrays. This review will discuss the history of these developments and provide examples of how they are currently being used to identify biomarkers and diagnose diseases such as cancer.
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10
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Biswas P, Adhikari A, Pal U, Mondal S, Mukherjee D, Ghosh R, Obaid RJ, Moussa Z, Choudhury SS, Ahmed SA, Das R, Pal SK. A combined spectroscopic and molecular modeling Study on structure-function-dynamics under chemical modification: Alpha-chymotrypsin with formalin preservative. Front Chem 2022; 10:978668. [PMID: 36118312 PMCID: PMC9473634 DOI: 10.3389/fchem.2022.978668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
Enzyme function can be altered via modification of its amino acid residues, side chains and large-scale domain modifications. Herein, we have addressed the role of residue modification in catalytic activity and molecular recognition of an enzyme alpha-chymotrypsin (CHT) in presence of a covalent cross-linker formalin. Enzyme assay reveals reduced catalytic activity upon increased formalin concentration. Polarization gated anisotropy studies of a fluorophore 8-Anilino-1-naphthalenesulfonic acid (ANS) in CHT show a dip rise pattern in presence of formalin which is consistent with the generation of multiple ANS binding sites in the enzyme owing to modifications of its local amino acid residues. Molecular docking study on amino acid residue modifications in CHT also indicate towards the formation of multiple ANS binding site. The docking model also predicted no change in binding behavior for the substrate Ala-Ala-Phe-7-amido-4-methylcoumarin (AMC) at the active site upon formalin induced amino acid cross-linking.
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Affiliation(s)
- Pritam Biswas
- Department of Microbiology, St. Xavier’s College, Kolkata, India
| | - Aniruddha Adhikari
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata, India
| | - Uttam Pal
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Kolkata, India
| | - Susmita Mondal
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata, India
| | - Dipanjan Mukherjee
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata, India
| | - Ria Ghosh
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Kolkata, India
| | - Rami J. Obaid
- Department of Chemistry, Faculty of Applied Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Ziad Moussa
- Department of Chemistry, College of Science, United Arab Emirates University, Al Ain, Abu Dhabi, United Arab Emirates
| | - Sudeshna Shyam Choudhury
- Department of Microbiology, St. Xavier’s College, Kolkata, India
- *Correspondence: Sudeshna Shyam Choudhury, ; Saleh A. Ahmed, ; Ranjan Das, ; Samir Kumar Pal,
| | - Saleh A. Ahmed
- Department of Chemistry, Faculty of Applied Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
- Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt
- *Correspondence: Sudeshna Shyam Choudhury, ; Saleh A. Ahmed, ; Ranjan Das, ; Samir Kumar Pal,
| | - Ranjan Das
- Department of Chemistry, West Bengal State University, Barasat, Kolkata, India
- *Correspondence: Sudeshna Shyam Choudhury, ; Saleh A. Ahmed, ; Ranjan Das, ; Samir Kumar Pal,
| | - Samir Kumar Pal
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata, India
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Kolkata, India
- *Correspondence: Sudeshna Shyam Choudhury, ; Saleh A. Ahmed, ; Ranjan Das, ; Samir Kumar Pal,
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11
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Long Z, Wei C, Ross R, Luo X, Ma X, Qi Y, Chai R, Cao J, Huang M, Bo T. Effects of detoxification process on toxicity and foreign protein of tetanus toxoid and diphtheria toxoid. J Chromatogr B Analyt Technol Biomed Life Sci 2022; 1207:123377. [PMID: 35905569 DOI: 10.1016/j.jchromb.2022.123377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/10/2022] [Accepted: 07/12/2022] [Indexed: 10/17/2022]
Abstract
Formaldehyde detoxification is a process for converting tetanus toxin (TT) and diphtheria toxin (DT) into tetanus toxoid (TTd) and diphtheria toxoid (DTd), respectively. The mechanism of this detoxification process has been investigated by several previous studies based on lab-scale toxoids. To obtain greater insights of the effects induced by formaldehyde, industrial TTd and DTd batches obtained from different detoxification processes were studied in this work. Using liquid chromatography-mass spectrometry (LC-MS), 15 and 20 repeatable formaldehyde-induced modification sites of TTd and DTd were identified, respectively. Toxoid which had a higher formaldehyde-induced modification rate observed by LC-MS, also had larger bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Aggregates which were observed on size exclusion chromatogram (SEC) were confirmed by SDS-PAGE and LC-MS. Formaldehyde detoxification also led to a decrease of isoelectric point (pI) values and an increase of retention on weak anion exchange (WAX) column. Specific toxicity tests were conducted to evaluate toxicity of the TTd and DTd samples obtained with different detoxification conditions. Results from the specific toxicity tests showed that all toxoids used in this study were qualified, including toxoids obtained from mild and drastic detoxification conditions. However, obtained from mild detoxification conditions had less aggregates and may lead to a higher degree of glycosylation in conjugate vaccines than the ones obtained from drastic detoxification conditions. Thus, we suggest that mild detoxification conditions should be used to obtain TTd and DTd. Furthermore, as well as studying the formaldehyde-induced modifications and toxicity in TTd and DTd, the effects of the detoxification process on foreign proteins were also investigated. An increase in foreign proteins were observed in the aggregate than in the monomer of the toxoids. Additionally, some foreign proteins in the monomer of the toxins transferred to the aggregate of toxoids due to the formation of cross-linking. To eliminate the risk of cross-linking foreign proteins to toxoids in vaccination programs, a purification process is necessary before the detoxification process and/or the use of toxoids in vaccines.
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Affiliation(s)
- Zhen Long
- ThermoFisher Scientific Corporation, Beijing 100080, China
| | - Chen Wei
- Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, National Institutes for Food and Drug Control, Beijing 100050, China
| | - Robert Ross
- ThermoFisher Scientific Corporation, San Jose 95134, USA
| | - Xi Luo
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Xiao Ma
- Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, National Institutes for Food and Drug Control, Beijing 100050, China.
| | - Yingzi Qi
- ThermoFisher Scientific Corporation, Beijing 100080, China
| | - Ruiping Chai
- ThermoFisher Scientific Corporation, Beijing 100080, China
| | - Jianming Cao
- ThermoFisher Scientific Corporation, Beijing 100080, China
| | - Min Huang
- ThermoFisher Scientific Corporation, Beijing 100080, China
| | - Tao Bo
- ThermoFisher Scientific Corporation, Beijing 100080, China
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12
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Yao B, Yang Y, Yu N, Tao N, Wang D, Wang S, Zhang F. Label-Free Quantification of Molecular Interaction in Live Red Blood Cells by Tracking Nanometer Scale Membrane Fluctuations. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2201623. [PMID: 35717672 PMCID: PMC9283308 DOI: 10.1002/smll.202201623] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Molecular interactions in live cells play an important role in both cellular functions and drug discovery. Current methods for measuring binding kinetics involve extracting the membrane protein and labeling, while the in situ quantification of molecular interaction with surface plasmon resonance (SPR) imaging mainly worked with fixed cells due to the micro-motion related noises of live cells. Here, an optical imaging method is presented to measure the molecular interaction with live red blood cells by tracking the nanometer membrane fluctuations. The membrane fluctuation dynamics are measured by tracking the membrane displacement during glycoprotein interaction. The data are analyzed with a thermodynamic model to determine the elastic properties of the cell observing reduced membrane fluctuations under fixatives, indicating cell fixations affect membrane mechanical properties. The binding kinetics of glycoprotein to several lectins are obtained by tracking the membrane fluctuation amplitude changes on single live cells. The binding kinetics and strength of different lectins are quite different, indicating the glycoproteins expression heterogeneity in single cells. It is anticipated that the method will contribute to the understanding of mechanisms of cell interaction and communication, and have potential applications in the mechanical assessment of cancer or other diseases at the single-cell level, and screening of membrane protein targeting drugs.
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Affiliation(s)
- Bo Yao
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, PR China
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Yunze Yang
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Nanxi Yu
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Nongjian Tao
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287, USA
| | - Di Wang
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- Intelligent Perception Research Institute, Zhejiang Laboratory, Hangzhou 311100, PR China
| | - Shaopeng Wang
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ 85287, USA
| | - Fenni Zhang
- Biosensor National Special Laboratory, Key Laboratory for Biomedical Engineering of Education Ministry, Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, PR China
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
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13
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Li B, Wan Z, Zheng H, Cai S, Tian HW, Tang H, Chu X, He G, Guo DS, Xue XS, Chen G. Construction of Complex Macromulticyclic Peptides via Stitching with Formaldehyde and Guanidine. J Am Chem Soc 2022; 144:10080-10090. [PMID: 35639413 DOI: 10.1021/jacs.2c04620] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
There is a growing interest in constructing multicyclic peptide structures to expand the chemical space of peptides. Conventional strategies for constructing large peptide structures are limited by the typical reliance on the inflexible coupling between premade templates equipped with fixed reactive handles and peptide substrates via cysteine anchors. Herein, we report the development of a facile three-component condensation reaction of primary alkyl amine, formaldehyde, and guanidine for construction of complex macromulticyclic peptides with novel topologies via lysine anchors. Moreover, the reaction sequences can be orchestrated in different anchor combinations and spatial arrangements to generate various macrocyclic structures crosslinked by distinct fused tetrahydrotriazine linkages. The macrocyclization reactions are selective, efficient, versatile, and workable in both organic and aqueous media. Thus, the condensation reaction provides a smart tool for stitching native peptides in situ using simple methylene threads and guanidine joints in a flexible and programmable manner.
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Affiliation(s)
- Bo Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zhao Wan
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Hanliang Zheng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shaokun Cai
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Han-Wen Tian
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Hong Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xin Chu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Dong-Sheng Guo
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiao-Song Xue
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.,Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.,Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
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14
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Zhu BT. Biochemical mechanism underlying the pathogenesis of diabetic retinopathy and other diabetic complications in humans: the methanol-formaldehyde-formic acid hypothesis. Acta Biochim Biophys Sin (Shanghai) 2022; 54:415-451. [PMID: 35607958 PMCID: PMC9828688 DOI: 10.3724/abbs.2022012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 11/18/2021] [Indexed: 11/25/2022] Open
Abstract
Hyperglycemia in diabetic patients is associated with abnormally-elevated cellular glucose levels. It is hypothesized that increased cellular glucose will lead to increased formation of endogenous methanol and/or formaldehyde, both of which are then metabolically converted to formic acid. These one-carbon metabolites are known to be present naturally in humans, and their levels are increased under diabetic conditions. Mechanistically, while formaldehyde is a cross-linking agent capable of causing extensive cytotoxicity, formic acid is an inhibitor of mitochondrial cytochrome oxidase, capable of inducing histotoxic hypoxia, ATP deficiency and cytotoxicity. Chronic increase in the production and accumulation of these toxic one-carbon metabolites in diabetic patients can drive the pathogenesis of ocular as well as other diabetic complications. This hypothesis is supported by a large body of experimental and clinical observations scattered in the literature. For instance, methanol is known to have organ- and species-selective toxicities, including the characteristic ocular lesions commonly seen in humans and non-human primates, but not in rodents. Similarly, some of the diabetic complications (such as ocular lesions) also have a characteristic species-selective pattern, closely resembling methanol intoxication. Moreover, while alcohol consumption or combined use of folic acid plus vitamin B is beneficial for mitigating acute methanol toxicity in humans, their use also improves the outcomes of diabetic complications. In addition, there is also a large body of evidence from biochemical and cellular studies. Together, there is considerable experimental support for the proposed hypothesis that increased metabolic formation of toxic one-carbon metabolites in diabetic patients contributes importantly to the development of various clinical complications.
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Affiliation(s)
- Bao Ting Zhu
- Shenzhen Key Laboratory of Steroid Drug Discovery and DevelopmentSchool of MedicineThe Chinese University of Hong KongShenzhen518172China
- Department of PharmacologyToxicology and TherapeuticsSchool of MedicineUniversity of Kansas Medical CenterKansas CityKS66160USA
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15
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A Non-Hazardous Deparaffinization Protocol Enables Quantitative Proteomics of Core Needle Biopsy-Sized Formalin-Fixed and Paraffin-Embedded (FFPE) Tissue Specimens. Int J Mol Sci 2022; 23:ijms23084443. [PMID: 35457260 PMCID: PMC9031572 DOI: 10.3390/ijms23084443] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 04/09/2022] [Accepted: 04/11/2022] [Indexed: 12/22/2022] Open
Abstract
Most human tumor tissues that are obtained for pathology and diagnostic purposes are formalin-fixed and paraffin-embedded (FFPE). To perform quantitative proteomics of FFPE samples, paraffin has to be removed and formalin-induced crosslinks have to be reversed prior to proteolytic digestion. A central component of almost all deparaffinization protocols is xylene, a toxic and highly flammable solvent that has been reported to negatively affect protein extraction and quantitative proteome analysis. Here, we present a 'green' xylene-free protocol for accelerated sample preparation of FFPE tissues based on paraffin-removal with hot water. Combined with tissue homogenization using disposable micropestles and a modified protein aggregation capture (PAC) digestion protocol, our workflow enables streamlined and reproducible quantitative proteomic profiling of FFPE tissue. Label-free quantitation of FFPE cores from human ductal breast carcinoma in situ (DCIS) xenografts with a volume of only 0.79 mm3 showed a high correlation between replicates (r2 = 0.992) with a median %CV of 16.9%. Importantly, this small volume is already compatible with tissue micro array (TMA) cores and core needle biopsies, while our results and its ease-of-use indicate that further downsizing is feasible. Finally, our FFPE workflow does not require costly equipment and can be established in every standard clinical laboratory.
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16
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Bachosz K, Piasecki A, Zdarta A, Kaczorek E, Pinelo M, Zdarta J, Jesionowski T. Enzymatic membrane reactor in xylose bioconversion with simultaneous cofactor regeneration. Bioorg Chem 2022; 123:105781. [PMID: 35395447 DOI: 10.1016/j.bioorg.2022.105781] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 12/22/2022]
Abstract
In this study, we present the concept of co-immobilization of xylose dehydrogenase and alcohol dehydrogenase from Saccharomyces cerevisiae on an XN45 nanofiltration membrane for application in the process of xylose bioconversion to xylonic acid with simultaneous cofactor regeneration and membrane separation of reaction products. During the research, the effectiveness of the co-immobilization of enzymes was confirmed, and changes in the properties of the membrane after the processes were determined. Using the obtained biocatalytic system it was possible to obtain 99% xylonic acid production efficiency under optimal conditions, which were 5 mM xylose, 5 mM formaldehyde, ratio of NAD+:NADH 1:1, and 60 min of reaction. Additionally, the co-immobilization of enzymes made it possible to improve stability of the co-immobilized enzymes and to carry out xylose conversion in six consecutive cycles and after 7 days of storage at 4 °C with over 90% efficiency. The presented data confirm the effectiveness of the co-immobilization, improvement of the stability and reusability of the biocatalysts, and show that the obtained enzymatic system is promising for use in xylose bioconversion and simultaneous regeneration of nicotinamide cofactor.
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Affiliation(s)
- Karolina Bachosz
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
| | - Adam Piasecki
- Institute of Materials Science and Engineering, Faculty of Mechanical Engineering and Management, Poznan University of Technology, Jana Pawla II 24, PL-60965 Poznan, Poland.
| | - Agata Zdarta
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
| | - Ewa Kaczorek
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
| | - Manuel Pinelo
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Soltofts Plads, Building 227, DK-2800 Kongens Lyngby, Denmark.
| | - Jakub Zdarta
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
| | - Teofil Jesionowski
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
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17
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Effects of polyol excipient stability during storage and use on the quality of biopharmaceutical formulations. J Pharm Anal 2022; 12:774-782. [PMID: 36320601 PMCID: PMC9615580 DOI: 10.1016/j.jpha.2022.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 02/19/2022] [Accepted: 03/16/2022] [Indexed: 11/30/2022] Open
Abstract
Biopharmaceuticals are formulated using a variety of excipients to maintain their storage stability. However, some excipients are prone to degradation during repeated use and/or improper storage, and the impurities generated by their degradation are easily overlooked by end users and are usually not strictly monitored, affecting the stability of biopharmaceuticals. In this study, we evaluated the degradation profile of polyol excipient glycerol during repeated use and improper storage and identified an unprecedented cyclic ketal impurity using gas chromatography with mass spectrometry (GC-MS). The other polyol excipient, mannitol, was much more stable than glycerol. The effects of degraded glycerol and mannitol on the stability of the model biopharmaceutical pentapeptide, thymopentin, were also evaluated. The thymopentin content was only 66.4% in the thymopentin formulations with degraded glycerol, compared to 95.8% in other formulations after the stress test. Most glycerol impurities (i.e., aldehydes and ketones) reacted with thymopentin, affecting the stability of thymopentin formulations. In conclusion, this work suggests that more attention should be paid to the quality changes of excipients during repeated use and storage. Additional testing of excipient stability under real or accelerated conditions by manufacturers would help avoid unexpected and painful results. Unprecedented impurities in degraded glycerol were identified with GC-MS. Degradation of thymopentin due to glycerol degradation was determined using LC-MS/MS. Excipient stability affects biopharmaceutical formulation quality.
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18
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Klein VJ, Irla M, Gil López M, Brautaset T, Fernandes Brito L. Unravelling Formaldehyde Metabolism in Bacteria: Road towards Synthetic Methylotrophy. Microorganisms 2022; 10:microorganisms10020220. [PMID: 35208673 PMCID: PMC8879981 DOI: 10.3390/microorganisms10020220] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 12/26/2022] Open
Abstract
Formaldehyde metabolism is prevalent in all organisms, where the accumulation of formaldehyde can be prevented through the activity of dissimilation pathways. Furthermore, formaldehyde assimilatory pathways play a fundamental role in many methylotrophs, which are microorganisms able to build biomass and obtain energy from single- and multicarbon compounds with no carbon–carbon bonds. Here, we describe how formaldehyde is formed in the environment, the mechanisms of its toxicity to the cells, and the cell’s strategies to circumvent it. While their importance is unquestionable for cell survival in formaldehyde rich environments, we present examples of how the modification of native formaldehyde dissimilation pathways in nonmethylotrophic bacteria can be applied to redirect carbon flux toward heterologous, synthetic formaldehyde assimilation pathways introduced into their metabolism. Attempts to engineer methylotrophy into nonmethylotrophic hosts have gained interest in the past decade, with only limited successes leading to the creation of autonomous synthetic methylotrophy. Here, we discuss how native formaldehyde assimilation pathways can additionally be employed as a premise to achieving synthetic methylotrophy. Lastly, we discuss how emerging knowledge on regulation of formaldehyde metabolism can contribute to creating synthetic regulatory circuits applied in metabolic engineering strategies.
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19
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Irgen-Gioro S, Yoshida S, Walling V, Chong S. Fixation can change the appearance of phase separation in living cells. eLife 2022; 11:79903. [PMID: 36444977 PMCID: PMC9817179 DOI: 10.7554/elife.79903] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 11/28/2022] [Indexed: 11/30/2022] Open
Abstract
Fixing cells with paraformaldehyde (PFA) is an essential step in numerous biological techniques as it is thought to preserve a snapshot of biomolecular transactions in living cells. Fixed-cell imaging techniques such as immunofluorescence have been widely used to detect liquid-liquid phase separation (LLPS) in vivo. Here, we compared images, before and after fixation, of cells expressing intrinsically disordered proteins that are able to undergo LLPS. Surprisingly, we found that PFA fixation can both enhance and diminish putative LLPS behaviors. For specific proteins, fixation can even cause their droplet-like puncta to artificially appear in cells that do not have any detectable puncta in the live condition. Fixing cells in the presence of glycine, a molecule that modulates fixation rates, can reverse the fixation effect from enhancing to diminishing LLPS appearance. We further established a kinetic model of fixation in the context of dynamic protein-protein interactions. Simulations based on the model suggest that protein localization in fixed cells depends on an intricate balance of protein-protein interaction dynamics, the overall rate of fixation, and notably, the difference between fixation rates of different proteins. Consistent with simulations, live-cell single-molecule imaging experiments showed that a fast overall rate of fixation relative to protein-protein interaction dynamics can minimize fixation artifacts. Our work reveals that PFA fixation changes the appearance of LLPS from living cells, presents a caveat in studying LLPS using fixation-based methods, and suggests a mechanism underlying the fixation artifact.
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Affiliation(s)
- Shawn Irgen-Gioro
- Division of Chemistry and Chemical Engineering, California Institute of TechnologyPasadenaUnited States
| | - Shawn Yoshida
- Division of Chemistry and Chemical Engineering, California Institute of TechnologyPasadenaUnited States,Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| | - Victoria Walling
- Division of Chemistry and Chemical Engineering, California Institute of TechnologyPasadenaUnited States
| | - Shasha Chong
- Division of Chemistry and Chemical Engineering, California Institute of TechnologyPasadenaUnited States
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20
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Zhao H, Huang X, Tong Z. Formaldehyde-Crosslinked Nontoxic Aβ Monomers to Form Toxic Aβ Dimers and Aggregates: Pathogenicity and Therapeutic Perspectives. ChemMedChem 2021; 16:3376-3390. [PMID: 34396700 DOI: 10.1002/cmdc.202100428] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/14/2021] [Indexed: 01/02/2023]
Abstract
Alzheimer's disease (AD) is characterized by the presence of senile plaques in the brain. However, medicines targeting amyloid-beta (Aβ) have not achieved the expected clinical effects. This review focuses on the formation mechanism of the Aβ dimer (the basic unit of oligomers and fibrils) and its tremendous potential as a drug target. Recently, age-associated formaldehyde and Aβ-derived formaldehyde have been found to crosslink the nontoxic Aβ monomer to form the toxic dimers, oligomers and fibrils. Particularly, Aβ-induced formaldehyde accumulation and formaldehyde-promoted Aβ aggregation form a vicious cycle. Subsequently, formaldehyde initiates Aβ toxicity in both the early-and late-onset AD. These facts also explain why AD drugs targeting only Aβ do not have the desired therapeutic effects. Development of the nanoparticle-based medicines targeting both formaldehyde and Aβ dimer is a promising strategy for improving the drug efficacy by penetrating blood-brain barrier and extracellular space into the cortical neurons in AD patients.
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Affiliation(s)
- Hang Zhao
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, School of Mental Health, Wenzhou Medical University, Wenzhou, 325035, China
| | - Xuerong Huang
- Wenzhou Medical University Affiliated Hospital 3, Department of Neurology, Wenzhou, 325200, China
| | - Zhiqian Tong
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, School of Mental Health, Wenzhou Medical University, Wenzhou, 325035, China
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21
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Silver Staining of 2D Electrophoresis Gels. Methods Mol Biol 2021. [PMID: 33950484 DOI: 10.1007/978-1-0716-1024-4_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Silver staining is used to detect proteins after electrophoretic separation on polyacrylamide gels. It combines excellent sensitivity (in the low nanogram range) with the use of very simple and cheap equipment and chemicals. For its use in proteomics, two important additional features must be considered, compatibility with mass spectrometry and quantitative response. Both features are discussed in this chapter, and optimized silver staining protocols are proposed.
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22
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Li B, Tang H, Turlik A, Wan Z, Xue X, Li L, Yang X, Li J, He G, Houk KN, Chen G. Cooperative Stapling of Native Peptides at Lysine and Tyrosine or Arginine with Formaldehyde. Angew Chem Int Ed Engl 2021; 60:6646-6652. [DOI: 10.1002/anie.202016267] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Bo Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Hong Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Aneta Turlik
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Zhao Wan
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Xiao‐Song Xue
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Li Li
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Xiaoxiao Yang
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Jiuyuan Li
- Asymchem Life Science Co., Ltd. TEDA Tianjin 300457 China
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Kendall N. Houk
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
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23
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Li B, Tang H, Turlik A, Wan Z, Xue X, Li L, Yang X, Li J, He G, Houk KN, Chen G. Cooperative Stapling of Native Peptides at Lysine and Tyrosine or Arginine with Formaldehyde. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bo Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Hong Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Aneta Turlik
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Zhao Wan
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Xiao‐Song Xue
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Li Li
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Xiaoxiao Yang
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Jiuyuan Li
- Asymchem Life Science Co., Ltd. TEDA Tianjin 300457 China
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Kendall N. Houk
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
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24
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Razavi M, Kompany-Zareh M, Khoshkam M. PARAFAC study of L-cys@CdTe QDs interaction to BSA, cytochrome c and trypsin: An approach through electrostatic and covalent bonds. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 246:119016. [PMID: 33038854 DOI: 10.1016/j.saa.2020.119016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 09/23/2020] [Accepted: 09/25/2020] [Indexed: 06/11/2023]
Abstract
Utilizing fluorescence spectroscopy, non-covalent and covalent interactions of L-cys@CdTe quantum dots to bovine serum albumin (BSA), cytochrome c and trypsin were investigated. L-cys@CdTe QDs with the emission maximum at 530 nm and an average diameter of 2.6 nm were synthesized in the aqueous medium. Formaldehyde, N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC) with N-hydroxysuccinimide (NHS), and glutaraldehyde was applied as cross-linkers. In the case of both electrostatic and covalent strategies PARAFAC, as a powerful multi-way chemometrics technique, was utilized to analyze fluorescence excitation-emission (EEM) spectra. For non-covalent and covalent bonding, two and three significant components composed the PARAFAC models. Resolved EEM shows that in the presence of formaldehyde, a new component with an emission peak similar to BSA was obtained. Using EDC-NHS cross-linker, the fluorescence peak of the newly formed component was in a distinct wavelength with similar emission intensity, compared to L-cys@CdTe QDs and BSA. Employing glutaraldehyde, a distinguished component was easily detected at emission wavelengths higher than that of L-cys@CdTe QDs and proteins. It was concluded that the choice of cross-linker is a critical step to create different emission spectra when dealing with nano-bio-conjugations. This study shows that glutaraldehyde cross-linker leads to increase sensitivity, selectivity, and accuracy of protein analysis.
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Affiliation(s)
- Mehri Razavi
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan 45137-66731, Iran
| | - Mohsen Kompany-Zareh
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan 45137-66731, Iran; Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. Box 1500, Halifax, NS B3H 4R2, Canada.
| | - Maryam Khoshkam
- Department of Chemistry, ّFaculty of Science, University of Mohaghegh Ardabili, 56199-11367, Ardabil, Iran
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25
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Tian Y, Bao Q, Wang N, Wan N, Lv L, Hao H, He C, Ye H. Time-Resolved Acetaldehyde-Based Accessibility Profiling Maps Ligand-Target Interactions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:519-530. [PMID: 33382614 DOI: 10.1021/jasms.0c00382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Elucidating ligand-protein interactions is important in understanding the biochemical machinery for given proteins. Previously, formaldehyde (FH)-based labeling has been employed to obtain such structural knowledge, since reactive residues that participate in ligand-target interactions display reduced accessibility to FH-labeling reagents, and thus can be identified by quantitative proteomics. Although being rapid and efficient for probing proteinaceous lysine accessibility, here, we report an acetaldehyde (AcH)-labeling approach that complements with FH for probing ligand-target interactions. AcH labeling examines lysine accessibility at a more moderate reaction speed and hence delivers a cleaner reaction when compared to that of FH. The subsequent application of AcH to label RNase A without and with ligands has assisted to assign lysines involved in ligand-RNase A binding by detecting the time-dependent changes in accessibility profiles. We further employed multiple reaction monitoring (MRM) to quantify these ligand-binding-responsive sites when a variety of potential ligands were queried. We noted that the time-resolved abundance changes of these peptides can sensitively determine the ligand-binding sites and differentiate binding affinities among these ligands, which was confirmed by native mass spectrometry (MS) and molecular docking. Lastly, we demonstrated that the binding sites can be recognized by monitoring the chemical accessibility of these responsive peptides in cell lysates. Together, we believe that the proposed combined use of AcH-based lysine accessibility profiling, native MS, and MRM screening is a powerful toolbox in characterizing ligand-target interactions, mapping topography, and interrogating affinities and holds promise for future applications in a complex cellular environment.
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Affiliation(s)
- Yang Tian
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Qiuyu Bao
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Nian Wang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Ning Wan
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Langlang Lv
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Haiping Hao
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Chaoyong He
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
| | - Hui Ye
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang #24, Nanjing, Jiangsu 210009, China
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26
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Single Point Mutation from E22-to-K in A β Initiates Early-Onset Alzheimer's Disease by Binding with Catalase. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2020:4981204. [PMID: 33425208 PMCID: PMC7775154 DOI: 10.1155/2020/4981204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 08/31/2020] [Accepted: 12/05/2020] [Indexed: 11/18/2022]
Abstract
Amyloid-beta (Aβ) is a critical etiological factor for late-onset familial Alzheimer's disease (AD). However, an early-onset AD has been found to be related with an Aβ mutation in glutamic acid 22-to-lysine (Italian type E22K). Why only one single point mutation at E22 residue induces AD remains unclear. Here, we report that a Chinese familial AD pedigree with E22K mutation was associated with higher levels of serum hydrogen peroxide (H2O2) and lower activity of catalase (a H2O2 degrading enzyme) than controls. Further, we found that E22K binding with catalase caused more severe H2O2 accumulation in the brains of E22K-injected rats than Aβ-injected rats. Unexpectedly, H2O2 bound with the mutation site 22K residue of E22K and elicited more rapid aggregation of E22K than Aβ in vitro. Moreover, H2O2 acted with E22K synergistically to induce higher cellular toxicity than with Aβ. Notably, intrahippocampal infusion of E22K led to more severe plaque deposition, neuron death, and more rapid memory decline than Aβ-injected rats. However, L-cysteine, a H2O2 scavenger, not only prevented self-aggregation of E22K but also reduced H2O2-promoted E22K assembly in vitro; subsequently, it alleviated Alzheimer-related phenotypes. Hence, E22K binding with catalase promotes the early onset of familial AD, and L-cys may reverse this disease.
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Labry C, Urvoy M. Formaldehyde preservation for deferred measurements of alkaline phosphatase activities in marine samples. Heliyon 2020; 6:e05333. [PMID: 33204870 PMCID: PMC7653066 DOI: 10.1016/j.heliyon.2020.e05333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 09/18/2020] [Accepted: 10/21/2020] [Indexed: 11/17/2022] Open
Abstract
Alkaline phosphatases are the main enzymes required by microorganisms to hydrolyse organic phosphorus into available phosphate in aquatic environments. The investigations of alkaline phosphatase activity (APA) usually generate numerous samples (size fractionation, Michaelis-Menten kinetics). Therefore, convenient and reliable preservation of incubated samples for a deferred analysis would be very useful when measurements cannot be performed right away. The APA of marine pond waters was measured using 4-Methylumbelliferyl phosphate (MUF-P) as the fluorogenic substrate modelling natural organic phosphorus compounds. Where typical inhibitors of other enzymatic activities, such as 1% sodium dodecyl sulfate, mercuric chloride, or buffered solutions of ammonium and glycine, failed to stop APA, the addition of formaldehyde efficiently inhibited APA. The effect of formaldehyde was the strongest with the highest concentration tested (4% final concentration) and in buffered (pH 8) solutions. Since a slow and gradual increase in APA may persist with time, the combination of the addition of 4% buffered formaldehyde with immediate freezing is the best method to entirely inhibit APA. The maximal rate of hydrolysis (Vmax) and the Michaelis constant (Km) of formaldehyde (4%)-inhibited samples did not significantly change during storage at -20 °C for 11 days. The method was successfully tested on samples with extremely high values of APA (15000–40000 nM h−1) that were preserved for 1 month at -20 °C (98% inhibition). This method is a reliable and useful means of preserving incubated samples, and it provides convenient controls for background fluorescence of water and substrate, without provoking abiotic hydrolysis of the substrate.
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Affiliation(s)
- C Labry
- Ifremer, DYNECO, F-29280 Plouzané, France
| | - M Urvoy
- Ifremer, DYNECO, F-29280 Plouzané, France.,Univ Brest, CNRS, IRD, Ifremer, LEMAR, F-29280 Plouzané, France
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28
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Zhao F, Liu L, Xu M, Shu X, Zheng L, Wei Z. Assessments of different inactivating reagents in formulating transmissible gastroenteritis virus vaccine. Virol J 2020; 17:163. [PMID: 33097081 PMCID: PMC7582447 DOI: 10.1186/s12985-020-01433-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/12/2020] [Indexed: 11/21/2022] Open
Abstract
Background Transmissible gastroenteritis virus (TGEV) causes enteric infection in piglets, characterized by vomiting, severe diarrhea and dehydration, and the mortality in suckling piglets is often high up to 100%. Vaccination is an effective measure to control the disease caused by TGEV. Methods In this study, cell-cultured TGEV HN-2012 strain was inactivated by formaldehyde (FA), β-propiolactone (BPL) or binaryethylenimine (BEI), respectively. Then the inactivated TGEV vaccine was prepared with freund's adjuvant, and the immunization effects were evaluated in mice. The TGEV-specific IgG level was detected by ELISA. The positive rates of CD4+, CD8+, CD4+IFN-γ+, CD4+IL-4+ T lymphocytes were detected by flow cytometry assay. Lymphocyte proliferation assay and gross pathology and histopathology examination were also performed to assess the three different inactivating reagents in formulating TGEV vaccine. Results The results showed that the TGEV-specific IgG level in FA group (n = 17) was earlier and stronger, while the BEI group produced much longer-term IgG level. The lymphocyte proliferation test demonstrated that the BEI group had a stronger ability to induce spleen lymphocyte proliferation. The positive rates of CD4+ and CD8+ T lymphocyte subsets of peripheral blood lymphocyte in BEI group was higher than that in FA group and BPL groups by flow cytometry assay. The positive rate of CD4+IFN-γ+ T lymphocyte subset was the highest in the BPL group, and the positive rate of CD4+IL-4+ T lymphocyte subset was the highest in the FA group. There were no obvious pathological changes in the vaccinated mice and the control group after the macroscopic and histopathological examination. Conclusions These results indicated that all the three experimental groups could induce cellular and humoral immunity, and the FA group had the best humoral immunity effect, while the BEI group showed its excellent cellular immunity effect.
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Affiliation(s)
- Fujie Zhao
- The College of Veterinary Medicine, Henan Agricultural University, Nongye Road 63#, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Lintao Liu
- The College of Veterinary Medicine, Henan Agricultural University, Nongye Road 63#, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Menglong Xu
- The College of Veterinary Medicine, Henan Agricultural University, Nongye Road 63#, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Xiangli Shu
- The College of Veterinary Medicine, Henan Agricultural University, Nongye Road 63#, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Lanlan Zheng
- The College of Veterinary Medicine, Henan Agricultural University, Nongye Road 63#, Zhengzhou, 450002, Henan Province, People's Republic of China.
| | - Zhanyong Wei
- The College of Veterinary Medicine, Henan Agricultural University, Nongye Road 63#, Zhengzhou, 450002, Henan Province, People's Republic of China. .,Key Laboratory for Animal-Derived Food Safety of Henan Province, Zhengzhou, 450002, Henan, China.
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29
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Macedo IS, Lima MVA, Souza JS, Rochael NC, Caldas PN, Barbosa HS, Lara FA, Saraiva EM, Mariante RM. Extracellular Traps Released by Neutrophils from Cats are Detrimental to Toxoplasma gondii Infectivity. Microorganisms 2020; 8:microorganisms8111628. [PMID: 33105542 PMCID: PMC7716220 DOI: 10.3390/microorganisms8111628] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/03/2020] [Accepted: 10/11/2020] [Indexed: 12/18/2022] Open
Abstract
Toxoplasma gondii is the causative agent of toxoplasmosis, an infectious disease that affects over 30% of the human world population, causing fatal infections in immunocompromised individuals and neonates. The life cycle of T. gondii is complex, and involves intermediate hosts (birds and mammals) and definitive hosts (felines, including domestic cats). The innate immune repertoire against the parasite involves the production of neutrophil extracellular traps (NET), and neutrophils from several intermediate hosts produce NET induced by T. gondii. However, the mechanisms underlying NET release in response to the parasite have been poorly explored. Therefore, the aims of this study were to investigate whether neutrophils from cats produce NET triggered by T. gondii and to understand the mechanisms thereby involved. Neutrophils from cats were stimulated with T. gondii tachyzoites and NET-derived DNA in the supernatant was quantified during the time. The presence of histone H1 and myeloperoxidase was detected by immunofluorescence. We observed that cat neutrophils produce both classical and rapid/early NET stimulated by T. gondii. Inhibition of elastase, intracellular calcium, and phosphatidylinositol 3-kinase (PI3K)-δ partially blocked classical NET release in response to the parasite. Electron microscopy revealed strands and networks of DNA in close contact or completely entrapping parasites. Live imaging showed that tachyzoites are killed by NET. We conclude that the production of NET is a conserved strategy to control infection by T. gondii amongst intermediate and definitive hosts.
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Affiliation(s)
- Isabela S. Macedo
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, RJ, Brazil; (I.S.M.); (M.V.A.L.); (J.S.S.); (H.S.B.)
| | - Marcos V. A. Lima
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, RJ, Brazil; (I.S.M.); (M.V.A.L.); (J.S.S.); (H.S.B.)
| | - Jéssica S. Souza
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, RJ, Brazil; (I.S.M.); (M.V.A.L.); (J.S.S.); (H.S.B.)
| | - Natalia C. Rochael
- Laboratório de Imunobiologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (N.C.R.); (E.M.S.)
| | - Pedro N. Caldas
- HVN Hospital Veterinário Niterói, Niterói 24360-440, RJ, Brazil;
| | - Helene S. Barbosa
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, RJ, Brazil; (I.S.M.); (M.V.A.L.); (J.S.S.); (H.S.B.)
| | - Flávio A. Lara
- Laboratório de Microbiologia Celular, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, RJ, Brazil;
| | - Elvira M. Saraiva
- Laboratório de Imunobiologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (N.C.R.); (E.M.S.)
| | - Rafael M. Mariante
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21040-360, RJ, Brazil; (I.S.M.); (M.V.A.L.); (J.S.S.); (H.S.B.)
- Correspondence: or ; Tel.: +55-21-2562-1018
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30
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Michiels TJM, Schöneich C, Hamzink MRJ, Meiring HD, Kersten GFA, Jiskoot W, Metz B. Novel Formaldehyde-Induced Modifications of Lysine Residue Pairs in Peptides and Proteins: Identification and Relevance to Vaccine Development. Mol Pharm 2020; 17:4375-4385. [PMID: 33017153 DOI: 10.1021/acs.molpharmaceut.0c00851] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Formaldehyde-inactivated toxoid vaccines have been in use for almost a century. Despite formaldehyde's deceptively simple structure, its reactions with proteins are complex. Treatment of immunogenic proteins with aqueous formaldehyde results in heterogenous mixtures due to a variety of adducts and cross-links. In this study, we aimed to further elucidate the reaction products of formaldehyde reaction with proteins and report unique modifications in formaldehyde-treated cytochrome c and corresponding synthetic peptides. Synthetic peptides (Ac-GDVEKGAK and Ac-GDVEKGKK) were treated with isotopically labeled formaldehyde (13CH2O or CD2O) followed by purification of the two main reaction products. This allowed for their structural elucidation by (2D)-nuclear magnetic resonance and nanoscale liquid chromatography-coupled mass spectrometry analysis. We observed modifications resulting from (i) formaldehyde-induced deamination and formation of α,β-unsaturated aldehydes and methylation on two adjacent lysine residues and (ii) formaldehyde-induced methylation and formylation of two adjacent lysine residues. These products react further to form intramolecular cross-links between the two lysine residues. At higher peptide concentrations, these two main reaction products were also found to subsequently cross-link to lysine residues in other peptides, forming dimers and trimers. The accurate identification and quantification of formaldehyde-induced modifications improves our knowledge of formaldehyde-inactivated vaccine products, potentially aiding the development and registration of new vaccines.
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Affiliation(s)
- Thomas J M Michiels
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, 2333 CC, Leiden, The Netherlands.,Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Christian Schöneich
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047, United States
| | - Martin R J Hamzink
- Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Hugo D Meiring
- Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Gideon F A Kersten
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, 2333 CC, Leiden, The Netherlands.,Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Wim Jiskoot
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, 2333 CC, Leiden, The Netherlands
| | - Bernard Metz
- Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
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31
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Bayer M, Angenendt L, Schliemann C, Hartmann W, König S. Are formalin-fixed and paraffin-embedded tissues fit for proteomic analysis? JOURNAL OF MASS SPECTROMETRY : JMS 2020; 55:e4347. [PMID: 30828905 DOI: 10.1002/jms.4347] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/12/2019] [Accepted: 02/25/2019] [Indexed: 06/09/2023]
Abstract
Formalin-fixed and paraffin-embedded (FFPE)-tissue archives are potential treasure troves in the search for clinically interesting specimens. However, while the FFPE-treatment provides excellent conservation of the three-dimensional structure of the tissue and prevents degradation over decades, it also introduces numerous nonspecific and irreversible protein modifications. In this study, we have evaluated several published workflows for FFPE-tissue by fit-for-purpose proteomics technologies. We demonstrate that many protein modifications and cross-links remain after treatment and conclude that the proteomics of FFPE-tissue is of value, but clear-cut limitations must be kept in mind. The analysis of abundant proteins in FFPE is straightforward, but confident identification of low-level proteins and/or biologically relevant modifications is seriously hampered by the FFPE-treatment. Peptide assignment should only be performed on high-quality spectra, even if this is at the cost of lower numbers of protein IDs. As Yergey and Coorssen stated in 2015: "Data quality is considered the primary criterion, and we thus emphasize that the standards of Analytical Chemistry must apply throughout any proteomic analysis."
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Affiliation(s)
- Malte Bayer
- Core Unit Proteomics, Interdisciplinary Center for Clinical Research, Medical Faculty, University of Münster, Münster, Germany
| | - Linus Angenendt
- Department of Medicine A, Haematology and Oncology, University Hospital Münster, Münster, Germany
| | - Christoph Schliemann
- Department of Medicine A, Haematology and Oncology, University Hospital Münster, Münster, Germany
| | - Wolfgang Hartmann
- Gerhard-Domagk-Institute of Pathology, University Hospital Münster, Münster, Germany
| | - Simone König
- Core Unit Proteomics, Interdisciplinary Center for Clinical Research, Medical Faculty, University of Münster, Münster, Germany
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32
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Michiels TJM, Meiring HD, Jiskoot W, Kersten GFA, Metz B. Formaldehyde treatment of proteins enhances proteolytic degradation by the endo-lysosomal protease cathepsin S. Sci Rep 2020; 10:11535. [PMID: 32665578 PMCID: PMC7360561 DOI: 10.1038/s41598-020-68248-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 06/17/2020] [Indexed: 11/11/2022] Open
Abstract
Enzymatic degradation of protein antigens by endo-lysosomal proteases in antigen-presenting cells is crucial for achieving cellular immunity. Structural changes caused by vaccine production process steps, such as formaldehyde inactivation, could affect the sensitivity of the antigen to lysosomal proteases. The aim of this study was to assess the effect of the formaldehyde detoxification process on the enzymatic proteolysis of antigens by studying model proteins. Bovine serum albumin, β-lactoglobulin A and cytochrome c were treated with various concentrations of isotopically labelled formaldehyde and glycine, and subjected to proteolytic digestion by cathepsin S, an important endo-lysosomal endoprotease. Degradation products were analysed by mass spectrometry and size exclusion chromatography. The most abundant modification sites were identified by their characteristic MS doublets. Unexpectedly, all studied proteins showed faster proteolytic degradation upon treatment with higher formaldehyde concentrations. This effect was observed both in the absence and presence of glycine, an often-used excipient during inactivation to prevent intermolecular crosslinking. Overall, subjecting proteins to formaldehyde or formaldehyde/glycine treatment results in changes in proteolysis rates, leading to an enhanced degradation speed. This accelerated degradation could have consequences for the immunogenicity and the efficacy of vaccine products containing formaldehyde-inactivated antigens.
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Affiliation(s)
- Thomas J M Michiels
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, 2333 CC, Leiden, The Netherlands.,Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Hugo D Meiring
- Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Wim Jiskoot
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, 2333 CC, Leiden, The Netherlands
| | - Gideon F A Kersten
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research (LACDR), Leiden University, 2333 CC, Leiden, The Netherlands.,Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands
| | - Bernard Metz
- Intravacc, Institute for Translational Vaccinology, 3721 MA, Bilthoven, The Netherlands.
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33
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Implementation of MALDI Mass Spectrometry Imaging in Cancer Proteomics Research: Applications and Challenges. J Pers Med 2020; 10:jpm10020054. [PMID: 32580362 PMCID: PMC7354689 DOI: 10.3390/jpm10020054] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/12/2020] [Accepted: 06/19/2020] [Indexed: 02/07/2023] Open
Abstract
Studying the proteome–the entire set of proteins in cells, tissues, organs and body fluids—is of great relevance in cancer research, as differential forms of proteins are expressed in response to specific intrinsic and extrinsic signals. Discovering protein signatures/pathways responsible for cancer transformation may lead to a better understanding of tumor biology and to a more effective diagnosis, prognosis, recurrence and response to therapy. Moreover, proteins can act as a biomarker or potential drug targets. Hence, it is of major importance to implement proteomic, particularly mass spectrometric, approaches in cancer research, to provide new crucial insights into tumor biology. Recently, mass spectrometry imaging (MSI) approaches were implemented in cancer research, to provide individual molecular characteristics of each individual tumor while retaining molecular spatial distribution, essential in the context of personalized disease management and medicine.
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34
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Mass spectrometry reveals the chemistry of formaldehyde cross-linking in structured proteins. Nat Commun 2020; 11:3128. [PMID: 32561732 PMCID: PMC7305180 DOI: 10.1038/s41467-020-16935-w] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/02/2020] [Indexed: 12/17/2022] Open
Abstract
Whole-cell cross-linking coupled to mass spectrometry is one of the few tools that can probe protein–protein interactions in intact cells. A very attractive reagent for this purpose is formaldehyde, a small molecule which is known to rapidly penetrate into all cellular compartments and to preserve the protein structure. In light of these benefits, it is surprising that identification of formaldehyde cross-links by mass spectrometry has so far been unsuccessful. Here we report mass spectrometry data that reveal formaldehyde cross-links to be the dimerization product of two formaldehyde-induced amino acid modifications. By integrating the revised mechanism into a customized search algorithm, we identify hundreds of cross-links from in situ formaldehyde fixation of human cells. Interestingly, many of the cross-links could not be mapped onto known atomic structures, and thus provide new structural insights. These findings enhance the use of formaldehyde cross-linking and mass spectrometry for structural studies. Formaldehyde (FA) is a popular cross-linking reagent, but applying it for cross-linking mass spectrometry (XLMS) has been largely unsuccessful. Here, the authors show that cross-links in structured proteins are the product of two FA molecules and identify hundreds of FA cross-links by XLMS in vitro and in situ.
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35
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Larsen JM, Bang-Berthelsen CH, Qvortrup K, Sancho AI, Hansen AH, Andersen KIH, Thacker SSN, Eiwegger T, Upton J, Bøgh KL. Production of allergen-specific immunotherapeutic agents for the treatment of food allergy. Crit Rev Biotechnol 2020; 40:881-894. [PMID: 32515236 DOI: 10.1080/07388551.2020.1772194] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Allergen-specific immunotherapy (IT) is emerging as a viable avenue for the treatment of food allergies. Clinical trials currently investigate raw or slightly processed foods as therapeutic agents, as trials using food-grade agents can be performed without the strict regulations to which conventional drugs are subjected. However, this limits the ability of standardization and may affect clinical trial outcomes and reproducibility. Herein, we provide an overview of methods used in the production of immunotherapeutic agents for the treatment of food allergies, including processed foods, allergen extracts, recombinant allergens, and synthetic peptides, as well as the physical and chemical processes for the reduction of protein allergenicity. Commercial interests currently favor producing standardized drug-grade allergen extracts for therapeutic use, and clinical trials are ongoing. In the near future, recombinant production could replace purification strategies since it allows the manufacturing of pure, native allergens or sequence-modified allergens with reduced allergenicity. A recurring issue within this field is the inadequate reporting of production procedures, quality control, product physicochemical characteristics, allergenicity, and immunological properties. This information is of vital importance in assessing therapeutic standardization and clinical safety profile, which are central parameters for the development of future therapeutic agents.
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Affiliation(s)
- Jeppe Madura Larsen
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | - Katrine Qvortrup
- Department of Chemistry, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ana Isabel Sancho
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | | | | | - Thomas Eiwegger
- Division of Immunology and Allergy, Food Allergy and Anaphylaxis Program, The Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada.,Research Institute, The Hospital for Sick Children, Translational Medicine Program, Toronto, Canada.,Department of Immunology, The University of Toronto, Toronto, Canada
| | - Julia Upton
- Division of Immunology and Allergy, Food Allergy and Anaphylaxis Program, The Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada
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36
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Berghmans E, Jacobs J, Deben C, Hermans C, Broeckx G, Smits E, Maes E, Raskin J, Pauwels P, Baggerman G. Mass Spectrometry Imaging Reveals Neutrophil Defensins as Additional Biomarkers for Anti-PD-(L)1 Immunotherapy Response in NSCLC Patients. Cancers (Basel) 2020; 12:E863. [PMID: 32252405 PMCID: PMC7225984 DOI: 10.3390/cancers12040863] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 12/17/2022] Open
Abstract
(1) Background: Therapeutic blocking of the interaction between programmed death-1 (PD-1) with its ligand PD-L1, an immune checkpoint, is a promising approach to restore the antitumor immune response. Improved clinical outcomes have been shown in different human cancers, including non-small cell lung cancer (NSCLC). Unfortunately, still a high number of NSCLC patients are treated with immunotherapy without obtaining any clinical benefit, due to the limitations of PD-L1 protein expression as the currently sole predictive biomarker for clinical use; (2) Methods: In this study, we applied mass spectrometry imaging (MSI) to discover new protein biomarkers, and to assess the possible correlation between candidate biomarkers and a positive immunotherapy response by matrix-assisted laser desorption/ionization (MALDI) MSI in 25 formalin-fixed paraffin-embedded (FFPE) pretreatment tumor biopsies (Biobank@UZA); (3) Results: Using MALDI MSI, we revealed that the addition of neutrophil defensin 1, 2 and 3 as pretreatment biomarkers may more accurately predict the outcome of immunotherapy treatment in NSCLC. These results were verified and confirmed with immunohistochemical analyses. In addition, we provide in-vitro evidence of the immune stimulatory effect of neutrophil defensins towards cancer cells; and (4) Conclusions: With proteomic approaches, we have discovered neutrophil defensins as additional prospective biomarkers for an anti-PD-(L)1 immunotherapy response. Thereby, we also demonstrated that the neutrophil defensins contribute in the activation of the immune response towards cancer cells, which could provide a new lead towards an anticancer therapy.
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Affiliation(s)
- Eline Berghmans
- Centre for Proteomics, University of Antwerp, 2020 Antwerpen, Belgium;
- Health Unit, VITO, 2400 Mol, Belgium
| | - Julie Jacobs
- Center for Oncological Research, University of Antwerp, 2610 Wilrijk, Belgium; (J.J.); (C.D.); (C.H.); (G.B.); (E.S.); (P.P.)
- Pathology Department, Antwerp University Hospital, 2650 Edegem, Belgium
| | - Christophe Deben
- Center for Oncological Research, University of Antwerp, 2610 Wilrijk, Belgium; (J.J.); (C.D.); (C.H.); (G.B.); (E.S.); (P.P.)
- Pathology Department, Antwerp University Hospital, 2650 Edegem, Belgium
| | - Christophe Hermans
- Center for Oncological Research, University of Antwerp, 2610 Wilrijk, Belgium; (J.J.); (C.D.); (C.H.); (G.B.); (E.S.); (P.P.)
- Pathology Department, Antwerp University Hospital, 2650 Edegem, Belgium
| | - Glenn Broeckx
- Center for Oncological Research, University of Antwerp, 2610 Wilrijk, Belgium; (J.J.); (C.D.); (C.H.); (G.B.); (E.S.); (P.P.)
- Pathology Department, Antwerp University Hospital, 2650 Edegem, Belgium
| | - Evelien Smits
- Center for Oncological Research, University of Antwerp, 2610 Wilrijk, Belgium; (J.J.); (C.D.); (C.H.); (G.B.); (E.S.); (P.P.)
- Center for Cell Therapy and Regenerative Medicine, Antwerp University Hospital, 2650 Edegem, Belgium
| | - Evelyne Maes
- Food & Bio-Based Products, AgResearch Ltd., Lincoln 7674, New Zealand;
| | - Jo Raskin
- Thoracic Oncology Department, Antwerp University Hospital, 2650 Edegem, Belgium;
| | - Patrick Pauwels
- Center for Oncological Research, University of Antwerp, 2610 Wilrijk, Belgium; (J.J.); (C.D.); (C.H.); (G.B.); (E.S.); (P.P.)
- Pathology Department, Antwerp University Hospital, 2650 Edegem, Belgium
| | - Geert Baggerman
- Centre for Proteomics, University of Antwerp, 2020 Antwerpen, Belgium;
- Health Unit, VITO, 2400 Mol, Belgium
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Formaldehyde Exposure and Epigenetic Effects: A Systematic Review. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10072319] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Formaldehyde (FA) is a general living and occupational pollutant, classified as carcinogenic for humans. Although genotoxicity is recognized as a FA mechanism of action, a potential contribution of epigenetic effects cannot be excluded. Therefore, aim of this review is to comprehensively assess possible epigenetic alterations induced by FA exposure in humans, animals, and cellular models. A systematic review of Pubmed, Scopus, and Isi Web of Science databases was performed. DNA global methylation changes were demonstrated in workers exposed to FA, and also in human bronchial cells. Histone alterations, i.e., the reduction in acetylation of histone lysine residues, in human lung cells were induced by FA. Moreover, a dysregulation of microRNA expression in human lung adenocarcinoma cells as well as in the nose, olfactory bulb and white blood cells of rodents and nonhuman primates was reported. Although preliminary, these findings suggest the role of epigenetic modifications as possible FA mechanisms of action that need deeper qualitative and quantitative investigation. This may allow to define the role of such alterations as indicators of early biological effect and the opportunity to include such information in future risk assessment and management strategies for public and occupationally FA-exposed populations.
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Meltretter J, Wüst J, Dittrich D, Lach J, Ludwig J, Eichler J, Pischetsrieder M. Untargeted Proteomics-Based Profiling for the Identification of Novel Processing-Induced Protein Modifications in Milk. J Proteome Res 2020; 19:805-818. [PMID: 31902209 DOI: 10.1021/acs.jproteome.9b00630] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nonenzymatic post-translational protein modifications (nePTMs) affect the nutritional, physiological, and technological properties of proteins in food and in vivo. In contrast to the usual targeted analyses, the present study determined nePTMs in processed milk in a truly untargeted proteomic approach. Thus, it was possible to determine to which extent known nePTM structures explain protein modifications in processed milk and to detect and identify novel products. The method combined ultrahigh-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry with bioinformatic data analysis by the software XCMS. The nePTMs detected by untargeted profiling of a β-lactoglobulin-lactose model were incorporated in a sensitive scheduled multiple reaction monitoring method to analyze these modifications in milk samples and to monitor their reaction kinetics during thermal treatment. Additionally, we identified the structures of unknown modifications. Lactosylation, carboxymethylation, formylation of lysine and N-terminus, glycation of arginine, oxidation of methionine, tryptophan, and cysteine, oxidative deamination of N-terminus, and deamidation of asparagine and glutamine were the most important reactions of β-lactoglobulin during milk processing. The isomerization of aspartic acid was observed for the first time in milk products, and N-terminal 4-imidazolidinone was identified as a novel nePTM.
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Affiliation(s)
- Jasmin Meltretter
- Department of Chemistry and Pharmacy, Food Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Johannes Wüst
- Department of Chemistry and Pharmacy, Food Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Daniel Dittrich
- Department of Chemistry and Pharmacy, Food Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Johannes Lach
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Jonas Ludwig
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Jutta Eichler
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
| | - Monika Pischetsrieder
- Department of Chemistry and Pharmacy, Food Chemistry, Emil Fischer Center , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Nikolaus-Fiebiger-Str. 10 , 91058 Erlangen , Germany
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Endogenous formaldehyde is a memory-related molecule in mice and humans. Commun Biol 2019; 2:446. [PMID: 31815201 PMCID: PMC6884489 DOI: 10.1038/s42003-019-0694-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 11/04/2019] [Indexed: 01/09/2023] Open
Abstract
Gaseous formaldehyde is an organic small molecule formed in the early stages of earth’s evolution. Although toxic in high concentrations, formaldehyde plays an important role in cellular metabolism and, unexpectedly, is found even in the healthy brain. However, its pathophysiological functions in the brain are unknown. Here, we report that under physiological conditions, spatial learning activity elicits rapid formaldehyde generation from mitochondrial sarcosine dehydrogenase (SARDH). We find that elevated formaldehyde levels facilitate spatial memory formation by enhancing N-methyl-D-aspartate (NMDA) currents via the C232 residue of the NMDA receptor, but that high formaldehyde concentrations gradually inactivate the receptor by cross-linking NR1 subunits to NR2B. We also report that in mice with aldehyde dehydrogenase-2 (ALDH2) knockout, formaldehyde accumulation due to hypofunctional ALDH2 impairs memory, consistent with observations of Alzheimerʼs disease patients. We also find that formaldehyde deficiency caused by mutation of the mitochondrial SARDH gene in children with sarcosinemia or in mice with Sardh deletion leads to cognitive deficits. Hence, we conclude that endogenous formaldehyde regulates learning and memory via the NMDA receptor. Ai et al. report that endogenous formaldehyde bidirectionally modulates cognition via the NMDA-R receptor, with both insufficiency and overabundance resulting in cognitive defects. The target site of formaldehyde enhancing NMDA-currents is cysteine C232 residue in amino terminal domain sequence of the NR2B subunit of NMDA-R and excessive formaldehyde suppresses NMDA-R activity by cross-linking NR1 to NR2B residues.
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Identification of Formaldehyde-Induced Modifications in Diphtheria Toxin. J Pharm Sci 2019; 109:543-557. [PMID: 31678246 DOI: 10.1016/j.xphs.2019.10.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/17/2019] [Accepted: 10/28/2019] [Indexed: 01/08/2023]
Abstract
Diphtheria toxoid is produced by detoxification of diphtheria toxin with formaldehyde. This study was performed to elucidate the chemical nature and location of formaldehyde-induced modifications in diphtheria toxoid. Diphtheria toxin was chemically modified using 4 different reactions with the following reagents: (1) formaldehyde and NaCNBH3, (2) formaldehyde, (3) formaldehyde and NaCNBH3 followed by formaldehyde and glycine, and (4) formaldehyde and glycine. The modifications were studied by SDS-PAGE, primary amino group determination, and liquid chromatography-electrospray mass spectrometry of chymotryptic digests. Reaction 1 resulted in quantitative dimethylation of all lysine residues. Reaction 2 caused intramolecular cross-links, including the NAD+-binding cavity and the receptor-binding site. Moreover, A fragments and B fragments were cross-linked by formaldehyde on part of the diphtheria toxoid molecules. Reaction 3 resulted in formaldehyde-glycine attachments, including in shielded areas of the protein. The detoxification reaction typically used for vaccine preparation (reaction 4) resulted in a combination of intramolecular cross-links and formaldehyde-glycine attachments. Both the NAD+-binding cavity and the receptor-binding site of diphtheria toxin were chemically modified. Although CD4+ T-cell epitopes were affected to some extent, one universal CD4+ T-cell epitope remained almost completely unaltered by the treatment with formaldehyde and glycine.
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Rakow S, Pullamsetti SS, Bauer UM, Bouchard C. Assaying epigenome functions of PRMTs and their substrates. Methods 2019; 175:53-65. [PMID: 31542509 DOI: 10.1016/j.ymeth.2019.09.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/09/2019] [Accepted: 09/16/2019] [Indexed: 12/20/2022] Open
Abstract
Among the widespread and increasing number of identified post-translational modifications (PTMs), arginine methylation is catalyzed by the protein arginine methyltransferases (PRMTs) and regulates fundamental processes in cells, such as gene regulation, RNA processing, translation, and signal transduction. As epigenetic regulators, PRMTs play key roles in pluripotency, differentiation, proliferation, survival, and apoptosis, which are essential biological programs leading to development, adult homeostasis but also pathological conditions including cancer. A full understanding of the molecular mechanisms that underlie PRMT-mediated gene regulation requires the genome wide mapping of each player, i.e., PRMTs, their substrates and epigenetic marks, methyl-marks readers as well as interaction partners, in a thorough and unambiguous manner. However, despite the tremendous advances in high throughput sequencing technologies and the numerous efforts from the scientific community, the epigenomic profiling of PRMTs as well as their histone and non-histone substrates still remains a big challenge owing to obvious limitations in tools and methodologies. This review will summarize the present knowledge about the genome wide mapping of PRMTs and their substrates as well as the technical approaches currently in use. The limitations and pitfalls of the technical tools along with conventional approaches will be then discussed in detail. Finally, potential new strategies for chromatin profiling of PRMTs and histone substrates will be proposed and described.
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Affiliation(s)
- Sinja Rakow
- Institute for Molecular Biology and Tumor Research (IMT), Philipps University of Marburg, Hans-Meerwein-Str. 2, BMFZ, 35043 Marburg, Germany
| | - Soni Savai Pullamsetti
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Uta-Maria Bauer
- Institute for Molecular Biology and Tumor Research (IMT), Philipps University of Marburg, Hans-Meerwein-Str. 2, BMFZ, 35043 Marburg, Germany
| | - Caroline Bouchard
- Institute for Molecular Biology and Tumor Research (IMT), Philipps University of Marburg, Hans-Meerwein-Str. 2, BMFZ, 35043 Marburg, Germany.
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Tea F, Lopez JA, Ramanathan S, Merheb V, Lee FXZ, Zou A, Pilli D, Patrick E, van der Walt A, Monif M, Tantsis EM, Yiu EM, Vucic S, Henderson APD, Fok A, Fraser CL, Lechner-Scott J, Reddel SW, Broadley S, Barnett MH, Brown DA, Lunemann JD, Dale RC, Brilot F. Characterization of the human myelin oligodendrocyte glycoprotein antibody response in demyelination. Acta Neuropathol Commun 2019; 7:145. [PMID: 31481127 PMCID: PMC6724269 DOI: 10.1186/s40478-019-0786-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 08/09/2019] [Indexed: 12/14/2022] Open
Abstract
Over recent years, human autoantibodies targeting myelin oligodendrocyte glycoprotein (MOG Ab) have been associated with monophasic and relapsing central nervous system demyelination involving the optic nerves, spinal cord, and brain. While the clinical relevance of MOG Ab detection is becoming increasingly clear as therapeutic and prognostic differences from multiple sclerosis are acknowledged, an in-depth characterization of human MOG Ab is required to answer key challenges in patient diagnosis, treatment, and prognosis. Herein, we investigated the epitope, binding sensitivity, and affinity of MOG Ab in a cohort of 139 and 148 MOG antibody-seropositive children and adults (n = 287 patients at baseline, 130 longitudinal samples, and 22 cerebrospinal fluid samples). MOG extracellular domain was also immobilized to determine the affinity of MOG Ab. MOG Ab response was of immunoglobulin G1 isotype, and was of peripheral rather than intrathecal origin. High affinity MOG Ab were detected in 15% paediatric and 18% adult sera. More than 75% of paediatric and adult MOG Ab targeted a dominant extracellular antigenic region around Proline42. MOG Ab titers fluctuated over the progression of disease, but affinity and reactivity to Proline42 remained stable. Adults with a relapsing course intrinsically presented with a reduced immunoreactivity to Proline42 and had a more diverse MOG Ab response, a feature that may be harnessed for predicting relapse. Higher titers of MOG Ab were observed in more severe phenotypes and during active disease, supporting the pathogenic role of MOG Ab. Loss of MOG Ab seropositivity was observed upon conformational changes to MOG, and this greatly impacted the sensitivity of the detection of relapsing disorders, largely considered as more severe. Careful consideration of the binding characteristics of autoantigens should be taken into account when detecting disease-relevant autoantibodies.
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Dapic I, Baljeu-Neuman L, Uwugiaren N, Kers J, Goodlett DR, Corthals GL. Proteome analysis of tissues by mass spectrometry. MASS SPECTROMETRY REVIEWS 2019; 38:403-441. [PMID: 31390493 DOI: 10.1002/mas.21598] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 06/17/2019] [Indexed: 06/10/2023]
Abstract
Tissues and biofluids are important sources of information used for the detection of diseases and decisions on patient therapies. There are several accepted methods for preservation of tissues, among which the most popular are fresh-frozen and formalin-fixed paraffin embedded methods. Depending on the preservation method and the amount of sample available, various specific protocols are available for tissue processing for subsequent proteomic analysis. Protocols are tailored to answer various biological questions, and as such vary in lysis and digestion conditions, as well as duration. The existence of diverse tissue-sample protocols has led to confusion in how to choose the best protocol for a given tissue and made it difficult to compare results across sample types. Here, we summarize procedures used for tissue processing for subsequent bottom-up proteomic analysis. Furthermore, we compare protocols for their variations in the composition of lysis buffers, digestion procedures, and purification steps. For example, reports have shown that lysis buffer composition plays an important role in the profile of extracted proteins: the most common are tris(hydroxymethyl)aminomethane, radioimmunoprecipitation assay, and ammonium bicarbonate buffers. Although, trypsin is the most commonly used enzyme for proteolysis, in some protocols it is supplemented with Lys-C and/or chymotrypsin, which will often lead to an increase in proteome coverage. Data show that the selection of the lysis procedure might need to be tissue-specific to produce distinct protocols for individual tissue types. Finally, selection of the procedures is also influenced by the amount of sample available, which range from biopsies or the size of a few dozen of mm2 obtained with laser capture microdissection to much larger amounts that weight several milligrams.
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Affiliation(s)
- Irena Dapic
- International Centre for Cancer Vaccine Science, University of Gdansk, Gdansk, Poland
| | | | - Naomi Uwugiaren
- International Centre for Cancer Vaccine Science, University of Gdansk, Gdansk, Poland
| | - Jesper Kers
- Department of Pathology, Amsterdam Infection & Immunity Institute (AI&II), Amsterdam Cardiovascular Sciences (ACS), Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA
| | - David R Goodlett
- International Centre for Cancer Vaccine Science, University of Gdansk, Gdansk, Poland
- University of Maryland, 20N. Pine Street, Baltimore, MD 21201
| | - Garry L Corthals
- van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
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Topical therapeutic corneal and scleral tissue cross-linking solutions: in vitro formaldehyde release studies using cosmetic preservatives. Biosci Rep 2019; 39:BSR20182392. [PMID: 30971499 PMCID: PMC6500889 DOI: 10.1042/bsr20182392] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/05/2019] [Accepted: 04/09/2019] [Indexed: 11/18/2022] Open
Abstract
Our recent tissue cross-linking studies using formaldehyde releasers (FARs) suggest that corneal and scleral tissue strengthening may be possible without using ultraviolet irradiation or epithelial removal, two requirements for the photochemical method in widespread clinical use. Thus, the present study was carried out in order to better understand these potential therapeutic solutions by studying the effects of concentration, pH, buffer, time, and tissue reactivity on formaldehyde release of these FARs. Three FARs, sodium hydroxymethyl glycinate (SMG), DMDM, and diazolidinyl urea (DAU) were studied using a chromotropic acid colorimetric FA assay. The effects of concentration, pH, and buffer were studied as well as the addition of corneal and scleral tissues. The main determinant of release was found to be dilution factor (concentration) in which maximal release was noted at the lowest concentrations studied (submillimolar). In time dependent studies, after 60 min, FA levels decreased by 38% for SMG, 30% for DMDM, and 19% for DAU with corneal tissue added; and by 40% for SMG, 40% for DMDM, and 15% for DAU with scleral tissue added. We conclude that concentration (dilution factor) was found to be the most important parameter governing the percent of FA released.
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Liu Z, Wang R, Liu J, Sun R, Wang F. Global Quantification of Intact Proteins via Chemical Isotope Labeling and Mass Spectrometry. J Proteome Res 2019; 18:2185-2194. [PMID: 30990045 DOI: 10.1021/acs.jproteome.9b00071] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Although thousands of intact proteins have been feasibly identified in recent years, global quantification of intact proteins is still challenging. Herein, we develop a high-throughput strategy for global intact protein quantification based on chemical isotope labeling. The isotope incorporation efficiency is as high as 99.2% for complex intact protein samples extracted from HeLa cells. Further, the pTop 2.0 software is developed for automated quantification of intact proteoforms in a high-throughput manner. The high quantification accuracy and reproducibility of this strategy have been demonstrated for both standard and complex cellular protein samples. A total of 2283 intact proteoforms originated from 660 protein accessions are successfully quantified under anaerobic and aerobic conditions and the differentially expressed proteins are observed to be involved in the important biological processes such as stress response.
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Affiliation(s)
- Zheyi Liu
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics , Chinese Academy of Sciences , Dalian , 116023 , China
| | - Ruimin Wang
- Institute of Computing Technology , Chinese Academy of Sciences , Beijing , 100190 , China
| | - Jing Liu
- College of Pharmacy , Dalian Medical University , Dalian , 116044 , China
| | - Ruixiang Sun
- Institute of Computing Technology , Chinese Academy of Sciences , Beijing , 100190 , China
| | - Fangjun Wang
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics , Chinese Academy of Sciences , Dalian , 116023 , China
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Zhang J, Yue X, Luo H, Jiang W, Mei Y, Ai L, Gao G, Wu Y, Yang H, An J, Ding S, Yang X, Sun B, Luo W, He R, Jia J, Lyu J, Tong Z. Illumination with 630 nm Red Light Reduces Oxidative Stress and Restores Memory by Photo-Activating Catalase and Formaldehyde Dehydrogenase in SAMP8 Mice. Antioxid Redox Signal 2019; 30:1432-1449. [PMID: 29869529 DOI: 10.1089/ars.2018.7520] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIMS Pharmacological treatments for Alzheimer's disease (AD) have not resulted in desirable clinical efficacy over 100 years. Hydrogen peroxide (H2O2), a reactive and the most stable compound of reactive oxygen species, contributes to oxidative stress in AD patients. In this study, we designed a medical device to emit red light at 630 ± 15 nm from a light-emitting diode (LED-RL) and investigated whether the LED-RL reduces brain H2O2 levels and improves memory in senescence-accelerated prone 8 mouse (SAMP8) model of age-related dementia. RESULTS We found that age-associated H2O2 directly inhibited formaldehyde dehydrogenase (FDH). FDH inactivity and semicarbazide-sensitive amine oxidase (SSAO) disorder resulted in endogenous formaldehyde (FA) accumulation. Unexpectedly, excess FA, in turn, caused acetylcholine (Ach) deficiency by inhibiting choline acetyltransferase (ChAT) activity in vitro and in vivo. Interestingly, the 630 nm red light can penetrate the skull and the abdomen with light penetration rates of ∼49% and ∼43%, respectively. Illumination with LED-RL markedly activated both catalase and FDH in the brains, cultured cells, and purified protein solutions, all reduced brain H2O2 and FA levels and restored brain Ach contents. Consequently, LED-RL not only prevented early-stage memory decline but also rescued late-stage memory deficits in SAMP8 mice. INNOVATION We developed a phototherapeutic device with 630 nm red light, and this LED-RL reduced brain H2O2 levels and reversed age-related memory disorders. CONCLUSIONS The phototherapy of LED-RL has low photo toxicity and high rate of tissue penetration and noninvasively reverses aging-associated cognitive decline. This finding opens a promising opportunity to translate LED-RL into clinical treatment for patients with dementia. Antioxid. Redox Signal. 00, 000-000.
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Affiliation(s)
- Jingnan Zhang
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
- 2 Center for Cognitive Disorders , Beijing Geriatric Hospital, Beijing, China
| | - Xiangpei Yue
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
| | - Hongjun Luo
- 3 Central Laboratory, Shantou University Medical College , Guangdong, China
| | - Wenjing Jiang
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
- 2 Center for Cognitive Disorders , Beijing Geriatric Hospital, Beijing, China
| | - Yufei Mei
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
- 4 School of Basic Medical Sciences, Zhejiang University , Hangzhou, China
| | - Li Ai
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
| | - Ge Gao
- 5 Department of Neurobiology, School of Basic Medical Sciences , Capital Medical University, Beijing, China
| | - Yan Wu
- 6 Department of Anatomy, School of Basic Medical Sciences , Capital Medical University, Beijing, China
| | - Hui Yang
- 5 Department of Neurobiology, School of Basic Medical Sciences , Capital Medical University, Beijing, China
| | - Jieran An
- 7 Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University , Wuhan, China
| | - Shumao Ding
- 7 Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University , Wuhan, China
| | - Xu Yang
- 7 Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University , Wuhan, China
| | - Binggui Sun
- 4 School of Basic Medical Sciences, Zhejiang University , Hangzhou, China
| | - Wenhong Luo
- 3 Central Laboratory, Shantou University Medical College , Guangdong, China
| | - Rongqiao He
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
- 8 State Key Laboratory of Brain & Cognitive Science, Institute of Biophysics, CAS Key Laboratory of Mental Health, University of Chinese Academy of Science, Beijing, China
| | - Jianping Jia
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
- 9 Department of Neurology, Xuanwu Hospital of the Capital Medical University , Beijing, China
| | - Jihui Lyu
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
- 2 Center for Cognitive Disorders , Beijing Geriatric Hospital, Beijing, China
| | - Zhiqian Tong
- 1 Laboratory of Alzheimer's Optoelectric Therapy, Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Capital Medical University , Beijing, China
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Hötzel KJ, Havnar CA, Ngu HV, Rost S, Liu SD, Rangell LK, Peale FV. Synthetic Antigen Gels as Practical Controls for Standardized and Quantitative Immunohistochemistry. J Histochem Cytochem 2019; 67:309-334. [PMID: 30879407 DOI: 10.1369/0022155419832002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Optimization and standardization of immunohistochemistry (IHC) protocols within and between laboratories requires reproducible positive and negative control samples. In many situations, suitable tissue or cell line controls are not available. We demonstrate here a method to incorporate target antigens into synthetic protein gels that can serve as IHC controls. The method can use peptides, protein domains, or whole proteins as antigens, and is compatible with a variety of fixation protocols. The resulting gels can be used to create tissue microarrays (TMAs) with a range of antigen concentrations that can be used to objectively quantify and calibrate chromogenic, fluorescent, or mass spectrometry-based IHC protocols. The method offers an opportunity to objectively quantify IHC staining results, and to optimize and standardize IHC protocols within and between laboratories. (J Histochem Cytochem 58:XXX-XXX, 2019).
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Affiliation(s)
- Kathy J Hötzel
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
| | - Charles A Havnar
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
| | - Hai V Ngu
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
| | - Sandra Rost
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
| | - Scot D Liu
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
| | - Linda K Rangell
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
| | - Franklin V Peale
- Department of Research Pathology, Genentech, Inc., South San Francisco, California
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Herrera-Rodriguez J, Signorazzi A, Holtrop M, de Vries-Idema J, Huckriede A. Inactivated or damaged? Comparing the effect of inactivation methods on influenza virions to optimize vaccine production. Vaccine 2019; 37:1630-1637. [PMID: 30765167 PMCID: PMC7115651 DOI: 10.1016/j.vaccine.2019.01.086] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 01/22/2019] [Accepted: 01/28/2019] [Indexed: 11/27/2022]
Abstract
β-propiolactone (BPL) and formaldehyde (FA) were used to inactivate several influenza virus strains. BPL abolished the infectivity, FA was unable to completely inactivate the virus. All methods damaged the binding and fusion capacity; BPL caused greater loss than FA. FA treatments caused the highest reduction in TLR-7 stimulation. All the observed effects were strain-dependent.
The vast majority of commercially available inactivated influenza vaccines are produced from egg-grown or cell-grown live influenza virus. The first step in the production process is virus inactivation with β-propiolactone (BPL) or formaldehyde (FA). Recommendations for production of inactivated vaccines merely define the maximal concentration for both reagents, leaving the optimization of the process to the manufacturers. We assessed the effect of inactivation with BPL and FA on 5 different influenza virus strains. The properties of the viral formulation, such as successful inactivation, preservation of hemagglutinin (HA) binding ability, fusion capacity and the potential to stimulate a Toll-like receptor 7 (TLR7) reporter cell line were then assessed and compared to the properties of the untreated virus. Inactivation with BPL resulted in undetectable infectivity levels, while FA-treated virus retained very low infectious titers. Hemagglutination and fusion ability were highly affected by those treatments that conferred higher inactivation, with BPL-treated virus binding and fusing at a lower degree compared to FA-inactivated samples. On the other hand, BPL-inactivated virus induced higher levels of activation of TLR7 than FA-inactivated virus. The alterations caused by BPL or FA treatments were virus strain dependent. This data shows that the inactivation procedures should be tailored on the virus strain, and that many other elements beside the concentration of the inactivating agent, such as incubation time and temperature, buffer and virus concentration, have to be defined to achieve a functional product.
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Affiliation(s)
- José Herrera-Rodriguez
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Aurora Signorazzi
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Marijke Holtrop
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Jacqueline de Vries-Idema
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Anke Huckriede
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
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Sompuram SR, Vani K, Schaedle AK, Balasubramanian A, Bogen SA. Selecting an Optimal Positive IHC Control for Verifying Antigen Retrieval. J Histochem Cytochem 2019; 67:275-289. [PMID: 30628843 DOI: 10.1369/0022155418824092] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Positive immunohistochemistry (IHC) controls are intended to detect problems in both immunostaining and heat-induced epitope retrieval (HIER). However, it is not known what features in a control are important for verifying HIER. Contrary to expectation, the fact that a tissue is formalin-fixed does not necessarily render it suitable in verifying proper HIER. Some tissue controls, for some immunostains, strongly stain even without HIER. Consequently, the control may verify the immunostain but provide little or no information regarding the HIER step. To sort this out, we used formalin-fixed peptide epitopes, a model that provides for precise definition of analyte concentration, epitope composition, and degree of fixation. Our data demonstrate that formalin fixation generates a variable level of protein epitope masking, depending on the epitope recognized by the primary antibody. Some epitopes are highly masked while others hardly at all. Furthermore, the ability of amino acids in the epitope to react with formaldehyde can, at least in part, account for this variability. Most important, we demonstrate the importance of selecting a positive control with a low or intermediate analyte concentration (relative to the immunostain's analytic sensitivity). High analyte concentrations can be insensitive in verifying the HIER step.
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Affiliation(s)
| | - Kodela Vani
- Medical Discovery Partners LLC, Boston, Massachusetts
| | | | | | - Steven A Bogen
- Medical Discovery Partners LLC, Boston, Massachusetts.,Department of Pathology and Laboratory Medicine, Tufts Medical Center, Boston, Massachusetts
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