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Madsen AV, Mejias-Gomez O, Pedersen LE, Preben Morth J, Kristensen P, Jenkins TP, Goletz S. Structural trends in antibody-antigen binding interfaces: a computational analysis of 1833 experimentally determined 3D structures. Comput Struct Biotechnol J 2024; 23:199-211. [PMID: 38161735 PMCID: PMC10755492 DOI: 10.1016/j.csbj.2023.11.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 01/03/2024] Open
Abstract
Antibodies are attractive therapeutic candidates due to their ability to bind cognate antigens with high affinity and specificity. Still, the underlying molecular rules governing the antibody-antigen interface remain poorly understood, making in silico antibody design inherently difficult and keeping the discovery and design of novel antibodies a costly and laborious process. This study investigates the characteristics of antibody-antigen binding interfaces through a computational analysis of more than 850,000 atom-atom contacts from the largest reported set of antibody-antigen complexes with 1833 nonredundant, experimentally determined structures. The analysis compares binding characteristics of conventional antibodies and single-domain antibodies (sdAbs) targeting both protein- and peptide antigens. We find clear patterns in the number antibody-antigen contacts and amino acid frequencies in the paratope. The direct comparison of sdAbs and conventional antibodies helps elucidate the mechanisms employed by sdAbs to compensate for their smaller size and the fact that they harbor only half the number of complementarity-determining regions compared to conventional antibodies. Furthermore, we pinpoint antibody interface hotspot residues that are often found at the binding interface and the amino acid frequencies at these positions. These findings have direct potential applications in antibody engineering and the design of improved antibody libraries.
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Affiliation(s)
- Andreas V. Madsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Oscar Mejias-Gomez
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Lasse E. Pedersen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - J. Preben Morth
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Timothy P. Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
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2
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Mejias-Gomez O, Braghetto M, Sørensen MKD, Madsen AV, Guiu LS, Kristensen P, Pedersen LE, Goletz S. Deep mining of antibody phage-display selections using Oxford Nanopore Technologies and Dual Unique Molecular Identifiers. N Biotechnol 2024; 80:56-68. [PMID: 38354946 DOI: 10.1016/j.nbt.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/05/2024] [Accepted: 02/11/2024] [Indexed: 02/16/2024]
Abstract
Antibody phage-display technology identifies antibody-antigen interactions through multiple panning rounds, but traditional screening gives no information on enrichment or diversity throughout the process. This results in the loss of valuable binders. Next Generation Sequencing can overcome this problem. We introduce a high accuracy long-read sequencing method based on the recent Oxford Nanopore Technologies (ONT) Q20 + chemistry in combination with dual unique molecular identifiers (UMIs) and an optimized bioinformatic analysis pipeline to monitor the selections. We identified binders from two single-domain antibody libraries selected against a model protein. Traditional colony-picking was compared with our ONT-UMI method. ONT-UMI enabled monitoring of diversity and enrichment before and after each selection round. By combining phage antibody selections with ONT-UMIs, deep mining of output selections is possible. The approach provides an alternative to traditional screening, enabling diversity quantification after each selection round and rare binder recovery, even when the dominating binder was > 99% abundant. Moreover, it can give insights on binding motifs for further affinity maturation and specificity optimizations. Our results demonstrate a platform for future data guided selection strategies.
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Affiliation(s)
- Oscar Mejias-Gomez
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Marta Braghetto
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Morten Kielsgaard Dziegiel Sørensen
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Andreas Visbech Madsen
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Laura Salse Guiu
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Section for Bioscience and Engineering, Aalborg University, Aalborg, Denmark
| | - Lasse Ebdrup Pedersen
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark.
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark.
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3
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Madsen AV, Pedersen LE, Kristensen P, Goletz S. Design and engineering of bispecific antibodies: insights and practical considerations. Front Bioeng Biotechnol 2024; 12:1352014. [PMID: 38333084 PMCID: PMC10850309 DOI: 10.3389/fbioe.2024.1352014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/15/2024] [Indexed: 02/10/2024] Open
Abstract
Bispecific antibodies (bsAbs) have attracted significant attention due to their dual binding activity, which permits simultaneous targeting of antigens and synergistic binding effects beyond what can be obtained even with combinations of conventional monospecific antibodies. Despite the tremendous therapeutic potential, the design and construction of bsAbs are often hampered by practical issues arising from the increased structural complexity as compared to conventional monospecific antibodies. The issues are diverse in nature, spanning from decreased biophysical stability from fusion of exogenous antigen-binding domains to antibody chain mispairing leading to formation of antibody-related impurities that are very difficult to remove. The added complexity requires judicious design considerations as well as extensive molecular engineering to ensure formation of high quality bsAbs with the intended mode of action and favorable drug-like qualities. In this review, we highlight and summarize some of the key considerations in design of bsAbs as well as state-of-the-art engineering principles that can be applied in efficient construction of bsAbs with diverse molecular formats.
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Affiliation(s)
- Andreas V. Madsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Lasse E. Pedersen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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4
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Mejias-Gomez O, Madsen AV, Pedersen LE, Kristensen P, Goletz S. Eliminating OFF-frame clones in randomized gene libraries: An improved split β-lactamase enrichment system. N Biotechnol 2023; 75:13-20. [PMID: 36889578 DOI: 10.1016/j.nbt.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/20/2023] [Accepted: 03/04/2023] [Indexed: 03/08/2023]
Abstract
Large, randomized libraries are a key technology for many biotechnological applications. While genetic diversity is the main parameter most libraries direct their resources on, less focus is devoted to ensuring functional IN-frame expression. This study describes a faster and more efficient system based on a split β-lactamase complementation for removal of OFF-frame clones and increase of functional diversity, suitable for construction of randomized libraries. The gene of interest is inserted between two fragments of the β-lactamase gene, conferring resistance to β-lactam drugs only upon expression of an inserted IN-frame gene without stop codons or frameshifts. The preinduction-free system was capable of eliminating OFF-frame clones in starting mixtures of as little as 1% IN-frame clones and enriching to about 70% IN-frame clones, even when their starting rate was as low as 0.001%. The curation system was verified by constructing a single-domain antibody phage display library using trinucleotide phosphoramidites for randomizing a complementary determining region, while eliminating OFF-frame clones and maximizing functional diversity.
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Affiliation(s)
- Oscar Mejias-Gomez
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Andreas V Madsen
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Lasse E Pedersen
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Section for Bioscience and Engineering, Aalborg University, Aalborg, Denmark
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Section for Protein Science and Biotherapeutics, Technical University of Denmark, Kongens Lyngby, Denmark.
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Dong J, Banwait B, Ueda H, Kristensen P. V H-Based Mini Q-Body: A Novel Quench-Based Immunosensor. Sensors (Basel) 2023; 23:2251. [PMID: 36850849 PMCID: PMC9960136 DOI: 10.3390/s23042251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/12/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
Quenchbodies (Q-bodies), a type of biosensor, are antibodies labeled with a fluorescent dye near the antigen recognition site. In the absence of an antigen, the dye is quenched by tryptophans in the antibody sequence; however, in its presence, the dye is displaced and therefore de-quenched. Although scFv and Fab are mainly used to create Q-bodies, this is the first report where a single-domain heavy chain VH from a semi-synthetic human antibody library formed the basis. To create a proof of concept "mini Q-body", a human anti-lysozyme single-domain VH antibody C3 was used. Mini Q-bodies were successfully developed using seven dyes. Different responses were observed depending on the dye and linker length; it was concluded that the optimal linker length for the TAMRA dye was C5, and rhodamine 6G was identified as the dye with the largest de-quenching response. Three single-domain antibodies with sequences similar to that of the C3 antibody were chosen, and the results confirmed the applicability of this method in developing mini Q-bodies. In summary, mini Q-bodies are an easy-to-use and time-saving method for detecting proteins.
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Affiliation(s)
- Jinhua Dong
- School of Rehabilitation Sciences and Engineering, University of Health and Rehabilitation Sciences, Qingdao 266071, China
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
- International Research Frontiers Initiative, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Bhagat Banwait
- Department of Engineering, Aarhus University, 8000 Aarhus, Denmark
| | - Hiroshi Ueda
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
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6
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Mejias-Gomez O, Madsen AV, Skovgaard K, Pedersen LE, Morth JP, Jenkins TP, Kristensen P, Goletz S. A window into the human immune system: comprehensive characterization of the complexity of antibody complementary-determining regions in functional antibodies. MAbs 2023; 15:2268255. [PMID: 37876265 PMCID: PMC10601506 DOI: 10.1080/19420862.2023.2268255] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 10/04/2023] [Indexed: 10/26/2023] Open
Abstract
The human immune system uses antibodies to neutralize foreign antigens. They are composed of heavy and light chains, both with constant and variable regions. The variable region has six hypervariable loops, also known as complementary-determining regions (CDRs) that determine antibody diversity and antigen specificity. Knowledge of their significance, and certain residues present in these areas, is vital for antibody therapeutics development. This study includes an analysis of more than 11,000 human antibody sequences from the International Immunogenetics information system (IMGT). The analysis included parameters such as length distribution, overall amino acid diversity, amino acid frequency per CDR and residue position within antibody chains. Overall, our findings confirm existing knowledge, such as CDRH3's high length diversity and amino acid variability, increased aromatic residue usage, particularly tyrosine, charged and polar residues like aspartic acid, serine, and the flexible residue glycine. Specific residue positions within each CDR influence these occurrences, implying a unique amino acid type distribution pattern. We compared amino acid type usage in CDRs and non-CDR regions, both in globular and transmembrane proteins, which revealed distinguishing features, such as increased frequency of tyrosine, serine, aspartic acid, and arginine. These findings should prove useful for future optimization, improvement of affinity, synthetic antibody library design, or the creation of antibodies de-novo in silico.
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Affiliation(s)
- Oscar Mejias-Gomez
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Andreas V. Madsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Kerstin Skovgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Lasse E. Pedersen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - J. Preben Morth
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Timothy P. Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
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7
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Madsen AV, Kristensen P, Buell AK, Goletz S. Generation of robust bispecific antibodies through fusion of single-domain antibodies on IgG scaffolds: a comprehensive comparison of formats. MAbs 2023; 15:2189432. [PMID: 36939220 PMCID: PMC10038023 DOI: 10.1080/19420862.2023.2189432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023] Open
Abstract
Bispecific antibodies (bsAbs) enable dual binding of different antigens with potential synergistic targeting effects and innovative therapeutic possibilities. The formation of bsAbs is, however, often dependent on complex engineering strategies with a high risk of antibody chain mispairing leading to contamination of the final product with incorrectly assembled antibody species. This study demonstrates formation of bsAbs in a generic and conceptually easy manner through fusion of single-domain antibodies (sdAbs) onto IgG scaffolds through flexible 10 amino acid linkers to form high-quality bsAbs with both binding functionalities intact and minimal product-related impurities. SdAbs are attractive fusion partners due to their small and monomeric nature combined with antigen-binding capabilities comparable to conventional human antibodies. By systematically comparing a comprehensive panel of symmetric αPD-L1×αHER2 antibodies, including reversely mirrored antigen specificities, we investigate how the molecular geometry affects production, stability, antigen binding and CD16a binding. SdAb fusion of the heavy chain was generally preferred over light chain fusion for promoting good expression and high biophysical stability as well as maintaining efficient binding to both antigens. We find that N-terminal sdAb fusion might sterically hinder antigen-binding to the Fv region of the IgG scaffold, whereas C-terminal fusion might disturb antigen-binding to the fused sdAb. Our work demonstrates a toolbox of complementary methods for in-depth analysis of key features, such as in-solution dual antigen binding, thermal stability, and aggregation propensity, to ensure high bsAb quality. These techniques can be executed at high-throughput and/or with very low material consumption and thus represent valuable tools for bsAb screening and development.
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Affiliation(s)
- Andreas V Madsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Alexander K Buell
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
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8
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Madsen A, Mejias-Gomez O, Pedersen LE, Skovgaard K, Kristensen P, Goletz S. Immobilization-Free Binding and Affinity Characterization of Higher Order Bispecific Antibody Complexes Using Size-Based Microfluidics. Anal Chem 2022; 94:13652-13658. [PMID: 36166291 PMCID: PMC9558742 DOI: 10.1021/acs.analchem.2c02705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 09/21/2022] [Indexed: 11/28/2022]
Abstract
Simultaneous targeting of different antigens by bispecific antibodies (bsAbs) is permitting synergistic binding functionalities with high therapeutic potential, but is also rendering their analysis challenging. We introduce flow-induced dispersion analysis (FIDA) for the in-depth characterization of bsAbs with diverse molecular architectures and valencies under near-native conditions without potentially obstructive surface immobilization. Individual equilibrium dissociation constants are determined in solution, even in higher-order complexes with both antigens involved, hereby allowing the analysis of binding cooperativity and elucidation of a potential interference between the interactions. We further illustrate bispecific binding functionality as incremental increases in complex sizes when the bsAbs are exposed to one or two antigens. The possibility for comprehensive binding analysis with low material consumption and high matrix tolerability irrespective of molecular format and with little optimization renders FIDA a versatile tool for format selection and characterization of complex bi/multispecific protein therapeutics throughout the drug development and biomanufacturing pipeline.
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Affiliation(s)
- Andreas
V. Madsen
- Department
of Biotechnology and Biomedicine, Technical
University of Denmark, Søltofts Plads, Building 224, 2800 Kgs. Lyngby, Denmark
| | - Oscar Mejias-Gomez
- Department
of Biotechnology and Biomedicine, Technical
University of Denmark, Søltofts Plads, Building 224, 2800 Kgs. Lyngby, Denmark
| | - Lasse E. Pedersen
- Department
of Biotechnology and Biomedicine, Technical
University of Denmark, Søltofts Plads, Building 224, 2800 Kgs. Lyngby, Denmark
| | - Kerstin Skovgaard
- Department
of Biotechnology and Biomedicine, Technical
University of Denmark, Søltofts Plads, Building 224, 2800 Kgs. Lyngby, Denmark
| | - Peter Kristensen
- Department
of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7, 9220 Aalborg, Denmark
| | - Steffen Goletz
- Department
of Biotechnology and Biomedicine, Technical
University of Denmark, Søltofts Plads, Building 224, 2800 Kgs. Lyngby, Denmark
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9
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Jessen MK, Andersen LW, Thomsen MH, Kristensen P, Hayeri W, Hassel RE, Messerschmidt TG, Sølling CG, Perner A, Petersen JAK, Kirkegaard H. Restrictive fluids versus standard care in adults with sepsis in the emergency department (REFACED): A multicenter, randomized feasibility trial. Acad Emerg Med 2022; 29:1172-1184. [PMID: 35652491 PMCID: PMC9804491 DOI: 10.1111/acem.14546] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/22/2022] [Accepted: 05/27/2022] [Indexed: 01/25/2023]
Abstract
BACKGROUND Fluid treatment in sepsis is a challenge and clinical equipoise exists regarding intravenous (IV) volumes. We aimed to determine whether a 24-h protocol restricting IV fluid was feasible in adult patients with sepsis without shock presenting to the emergency department (ED). METHODS The REFACED Sepsis trial is an investigator-initiated, multicenter, randomized, open-label, feasibility trial, assigning sepsis patients without shock to 24 h of restrictive, crystal IV fluid administration or standard care. In the IV fluid restriction group fluid boluses were only permitted if predefined criteria for hypoperfusion occurred. Standard care was at the discretion of the treating team. The primary outcome was total IV crystalloid fluid volumes at 24 h after randomization. Secondary outcomes included total fluid volumes, feasibility measures, and patient-centered outcomes. RESULTS We included 123 patients (restrictive 61 patients and standard care 62 patients) in the primary analysis. A total of 32% (95% confidence interval [CI] 28%-37%) of eligible patients meeting all inclusion criteria and no exclusion criteria were included. At 24 h, the mean (±SD) IV crystalloid fluid volumes were 562 (±1076) ml versus 1370 (±1438) ml in the restrictive versus standard care group (mean difference -801 ml, 95% CI -1257 to -345 ml, p = 0.001). Protocol violations occurred in 21 (34%) patients in the fluid-restrictive group. There were no differences between groups in adverse events, use of mechanical ventilation or vasopressors, acute kidney failure, length of stay, or mortality. CONCLUSIONS A protocol restricting IV crystalloid fluids in ED patients with sepsis reduced 24-h fluid volumes compared to standard care. A future trial powered toward patient-centered outcomes appears feasible.
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Affiliation(s)
- Marie K. Jessen
- Department of Clinical Medicine, Research Center for Emergency MedicineAarhus University and Aarhus University HospitalAarhusDenmark,Department of Emergency MedicineAarhus University HospitalAarhusDenmark
| | - Lars W. Andersen
- Department of Clinical Medicine, Research Center for Emergency MedicineAarhus University and Aarhus University HospitalAarhusDenmark,Department of Anesthesiology and Intensive CareAarhus University HospitalAarhusDenmark,Prehospital Emergency Medical ServicesCentral Denmark RegionAarhusDenmark
| | - Marie‐Louise H. Thomsen
- Department of Clinical Medicine, Research Center for Emergency MedicineAarhus University and Aarhus University HospitalAarhusDenmark,Department of Emergency MedicineAarhus University HospitalAarhusDenmark
| | - Peter Kristensen
- Department of Emergency MedicineRegional Hospital ViborgViborgDenmark
| | - Wazhma Hayeri
- Department of Emergency MedicineRegional Hospital RandersRandersDenmark
| | - Ranva E. Hassel
- Department of Emergency MedicineAarhus University HospitalAarhusDenmark
| | | | | | - Anders Perner
- Department of Intensive CareCopenhagen University Hospital, RigshospitaletCopenhagenDenmark
| | - Jens Aage K. Petersen
- Department of Anesthesiology and Intensive CareAarhus University HospitalAarhusDenmark
| | - Hans Kirkegaard
- Department of Clinical Medicine, Research Center for Emergency MedicineAarhus University and Aarhus University HospitalAarhusDenmark,Department of Emergency MedicineAarhus University HospitalAarhusDenmark,Prehospital Emergency Medical ServicesCentral Denmark RegionAarhusDenmark
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10
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Fan W, Du T, Droce A, Jensen LR, Youngman RE, Ren X, Gurevich L, Bauchy M, Kristensen P, Xing B, Yu D, Smedskjaer MM. Resolving the Conflict between Strength and Toughness in Bioactive Silica-Polymer Hybrid Materials. ACS Nano 2022; 16:9748-9761. [PMID: 35679120 DOI: 10.1021/acsnano.2c03440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Simultaneously improving the strength and toughness of materials is a major challenge. Inorganic-polymer hybrids offer the potential to combine mechanical properties of a stiff inorganic glass with a flexible organic polymer. However, the toughening mechanism at the atomic scale remains largely unknown. Based on combined experimental and molecular dynamics simulation results, we find that the deformation and fracture behavior of hybrids are governed by noncovalent intermolecular interactions between polymer and silica networks rather than the breakage of covalent bonds. We then attempt three methods to improve the balance between strength and toughness of hybrids, namely the total inorganic/organic (I/O) weight ratio, the size of silica nanoparticles, and the ratio of -C-O vs -C-C bonds in the polymer chains. Specifically, for a hybrid with matched silica size and I/O ratio, we demonstrate optimized mechanical properties in terms of strength (1.75 MPa at breakage), degree of elongation at the fracture point (31%), toughness (219 kPa), hardness (1.08 MPa), as well as Young's modulus (3.0 MPa). We also demonstrate that this hybrid material shows excellent biocompatibility and ability to support cell attachment as well as proliferation. This supports the possible application of this material as a strong yet tough bone scaffold material.
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Affiliation(s)
- Wei Fan
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Tao Du
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Aida Droce
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Lars R Jensen
- Department of Materials and Production, Aalborg University, 9220 Aalborg, Denmark
| | - Randall E Youngman
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, United States
| | - Xiangting Ren
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Leonid Gurevich
- Department of Materials and Production, Aalborg University, 9220 Aalborg, Denmark
| | - Mathieu Bauchy
- Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, United States
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Bengang Xing
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Donghong Yu
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Morten M Smedskjaer
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
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11
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Keller JG, Hymøller KM, Thorsager ME, Hansen NY, Erlandsen JU, Tesauro C, Simonsen AKW, Andersen AB, VandsøPetersen K, Holm LL, Stougaard M, Andresen BS, Kristensen P, Frøhlich R, Knudsen BR. Topoisomerase 1 inhibits MYC promoter activity by inducing G-quadruplex formation. Nucleic Acids Res 2022; 50:6332-6342. [PMID: 35687110 PMCID: PMC9226537 DOI: 10.1093/nar/gkac482] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/28/2022] [Accepted: 06/07/2022] [Indexed: 11/23/2022] Open
Abstract
We have investigated the function of human topoisomerase 1 (TOP1) in regulation of G-quadruplex (G4) formation in the Pu27 region of the MYC P1 promoter. Pu27 is among the best characterized G4 forming sequences in the human genome and it is well known that promoter activity is inhibited upon G4 formation in this region. We found that TOP1 downregulation stimulated transcription from a promoter with wildtype Pu27 but not if the G4 motif in Pu27 was interrupted by mutation(s). The effect was not specific to the MYC promoter and similar results were obtained for the G4 forming promoter element WT21. The other major DNA topoisomerases with relaxation activity, topoisomerases 2α and β, on the other hand, did not affect G4 dependent promoter activity. The cellular studies were supported by in vitro investigations demonstrating a high affinity of TOP1 for wildtype Pu27 but not for mutant sequences unable to form G4. Moreover, TOP1 was able to induce G4 formation in Pu27 inserted in double stranded plasmid DNA in vitro. This is the first time TOP1 has been demonstrated capable of inducing G4 formation in double stranded DNA and of influencing G4 formation in cells.
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Affiliation(s)
- Josephine Geertsen Keller
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark.,Department of Clinical Medicine, Aarhus University, 8000 Aarhus C, Denmark
| | | | | | - Noriko Y Hansen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
| | - Jens Uldum Erlandsen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
| | - Cinzia Tesauro
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
| | | | - Anne Bech Andersen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
| | | | - Lise Lolle Holm
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark.,Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Magnus Stougaard
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus C, Denmark.,Department of Pathology, Aarhus University Hospital, 8000 Aarhus C, Denmark
| | - Brage Storstein Andresen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark.,Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Peter Kristensen
- Faculty of Engineering and Science, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Rikke Frøhlich
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
| | - Birgitta R Knudsen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
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12
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Jessen MK, Andersen LW, Thomsen MLH, Kristensen P, Hayeri W, Hassel RE, Perner A, Petersen JAK, Kirkegaard H. Restrictive Fluid Administration vs. Standard of Care in Emergency Department Sepsis Patients (REFACED Sepsis)-protocol for a multicenter, randomized, clinical, proof-of-concept trial. Pilot Feasibility Stud 2022; 8:75. [PMID: 35351214 PMCID: PMC8962933 DOI: 10.1186/s40814-022-01034-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 03/17/2022] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Intravenous fluids are often used in the treatment of sepsis. The better strategy regarding fluid volume is debated, but preliminary data in patients with septic shock or sepsis-related hypotension favor restrictive fluid administration. We describe the protocol and statistical analysis plan for the Restrictive Fluid Administration vs. Standard of Care in Emergency Department Sepsis Patients (REFACED Sepsis)-a multicenter, randomized clinical proof-of-concept trial. The aim of the REFACED Sepsis trial is to test if a restrictive intravenous fluid protocol in emergency department patients with sepsis without shock is feasible and decreases the intravenous fluid volume administered in comparison to standard care. METHODS This is an investigator-initiated, multicenter, randomized, parallel-group, open-labeled, feasibility trial investigating volumes of crystalloid fluid within 24 h in 124 patients with sepsis without shock enrolled at three emergency departments in the Central Denmark Region. Patients are allocated to two different intravenous fluid regimens: a restrictive approach using four trigger criteria for fluid administration vs. standard care. The primary, feasibility outcome is total intravenous, crystalloid fluid volume within 24 h, and key secondary outcomes include protocol violations, total fluids (intravenous and oral) within 24 h, and serious adverse reactions and suspected unexpected serious adverse reactions. Status: The trial started in November 2021, and the last patient is anticipated to be included in January 2022. DISCUSSION Sepsis is very common in emergency department patients and fluid administration is very frequently administered in these patients. However, the evidence to guide fluid administration is very sparse. This feasibility trial will be the foundation for a potential future large-scale trial investigating restrictive vs. standard fluid administration in patients with sepsis. TRIAL REGISTRATION EudraCT number: 2021-000224-35 (date: 2021 May 03), ClinicalTrials.gov number: NCT05076435 (date: 2021 October 13), Committee on Health Research Ethics - Central Denmark Region: 1-10-72-163-21 (date: 2021 June 28).
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Affiliation(s)
- Marie Kristine Jessen
- Research Center for Emergency Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, J103, DK-8200, Aarhus N, Denmark. .,Department of Emergency Medicine, Aarhus University Hospital, Aarhus N, Denmark.
| | - Lars Wiuff Andersen
- Research Center for Emergency Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, J103, DK-8200, Aarhus N, Denmark.,Department of Anesthesiology and Intensive Care, Aarhus University Hospital, Aarhus N, Denmark.,Prehospital Emergency Medical Services, Central Denmark Region, Aarhus N, Denmark
| | | | - Peter Kristensen
- Department of Emergency Medicine, Regional Hospital Viborg, Viborg, Denmark
| | - Wazhma Hayeri
- Department of Emergency Medicine, Regional Hospital Randers, Randers, Denmark
| | | | - Anders Perner
- Department of Intensive Care, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | | | - Hans Kirkegaard
- Research Center for Emergency Medicine, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, J103, DK-8200, Aarhus N, Denmark.,Prehospital Emergency Medical Services, Central Denmark Region, Aarhus N, Denmark
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13
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Zhang Y, Breum NMD, Schubert S, Hashemi N, Kyhnau R, Knauf MS, Mathialakan M, Takeuchi M, Kishino S, Ogawa J, Kristensen P, Guo Z, Eser BE. Semi-rational Engineering of a Promiscuous Fatty Acid Hydratase for Alteration of Regioselectivity. Chembiochem 2021; 23:e202100606. [PMID: 34929055 DOI: 10.1002/cbic.202100606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/14/2021] [Indexed: 11/12/2022]
Abstract
Fatty acid hydratases (FAHs) catalyze regio- and stereo-selective hydration of unsaturated fatty acids to produce hydroxy fatty acids. Fatty acid hydratase-1 (FA-HY1) from Lactobacillus Acidophilus is the most promiscuous and regiodiverse FAH identified so far. Here, we engineered binding site residues of FA-HY1 (S393, S395, S218 and P380) by semi-rational protein engineering to alter regioselectivity. Although it was not possible to obtain a completely new type of regioselectivity with our mutant libraries, a significant shift of regioselectivity was observed towards cis-5, cis-8, cis-11, cis-14, cis-17-eicosapentaenoic acid (EPA). We identified mutants (S393/S395 mutants) with excellent regioselectivity, generating a single hydroxy fatty acid product from EPA (15-OH product), which is advantageous from application perspective. This result is impressive given that wild-type FA-HY1 produces a mixture of 12-OH and 15-OH products at 63 : 37 ratio (12-OH : 15-OH). Moreover, our results indicate that native FA-HY1 is at its limit in terms of promiscuity and regiospecificity, thus it may not be possible to diversify its product portfolio with active site engineering. This behavior of FA-HY1 is unlike its orthologue, fatty acid hydratase-2 (FA-HY2; 58 % sequence identity to FA-HY1), which has been shown earlier to exhibit significant promiscuity and regioselectivity changes by a few active site mutations. Our reverse engineering from FA-HY1 to FA-HY2 further demonstrates this conclusion.
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Affiliation(s)
- Yan Zhang
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | | | - Sune Schubert
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | - Negin Hashemi
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | - Rikke Kyhnau
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | - Marius Sandholt Knauf
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | - Masuthan Mathialakan
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | - Michiki Takeuchi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Shigenobu Kishino
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Jun Ogawa
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Peter Kristensen
- Faculty of Engineering and Science, Department of Chemistry and Bioscience, Aalborg University, 9220, Aalborg, Denmark
| | - Zheng Guo
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
| | - Bekir Engin Eser
- Department of Biological and Chemical Engineering, Aarhus University, 8000, Aarhus, Denmark
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14
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Zhang Y, Eser BE, Kougioumtzoglou G, Eser Z, Poborsky M, Kishino S, Takeuchi M, Ogawa J, Kristensen P, Guo Z. Effects of the engineering of a single binding pocket residue on specificity and regioselectivity of hydratases from Lactobacillus Acidophilus. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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15
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Lemm JU, Venohr M, Globevnik L, Stefanidis K, Panagopoulos Y, van Gils J, Posthuma L, Kristensen P, Feld CK, Mahnkopf J, Hering D, Birk S. Multiple stressors determine river ecological status at the European scale: Towards an integrated understanding of river status deterioration. Glob Chang Biol 2021; 27:1962-1975. [PMID: 33372367 DOI: 10.1111/gcb.15504] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 11/16/2020] [Accepted: 12/11/2020] [Indexed: 05/22/2023]
Abstract
The biota of European rivers are affected by a wide range of stressors impairing water quality and hydro-morphology. Only about 40% of Europe's rivers reach 'good ecological status', a target set by the European Water Framework Directive (WFD) and indicated by the biota. It is yet unknown how the different stressors in concert impact ecological status and how the relationship between stressors and status differs between river types. We linked the intensity of seven stressors to recently measured ecological status data for more than 50,000 sub-catchment units (covering almost 80% of Europe's surface area), which were distributed among 12 broad river types. Stressor data were either derived from remote sensing data (extent of urban and agricultural land use in the riparian zone) or modelled (alteration of mean annual flow and of base flow, total phosphorous load, total nitrogen load and mixture toxic pressure, a composite metric for toxic substances), while data on ecological status were taken from national statutory reporting of the second WFD River Basin Management Plans for the years 2010-2015. We used Boosted Regression Trees to link ecological status to stressor intensities. The stressors explained on average 61% of deviance in ecological status for the 12 individual river types, with all seven stressors contributing considerably to this explanation. On average, 39.4% of the deviance was explained by altered hydro-morphology (morphology: 23.2%; hydrology: 16.2%), 34.4% by nutrient enrichment and 26.2% by toxic substances. More than half of the total deviance was explained by stressor interaction, with nutrient enrichment and toxic substances interacting most frequently and strongly. Our results underline that the biota of all European river types are determined by co-occurring and interacting multiple stressors, lending support to the conclusion that fundamental management strategies at the catchment scale are required to reach the ambitious objective of good ecological status of surface waters.
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Affiliation(s)
- Jan U Lemm
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
| | - Markus Venohr
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Berlin, Germany
| | - Lidija Globevnik
- Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, Slovenia
- TC Vode, Ljubljana, Slovenia
| | - Kostas Stefanidis
- Center for Hydrology and Informatics, National Technical University of Athens, Athens, Greece
- Hellenic Center for Marine Research, Institute of Marine Biological Resources and Inland Waters, Anavissos Attikis, Greece
| | - Yiannis Panagopoulos
- Center for Hydrology and Informatics, National Technical University of Athens, Athens, Greece
- Hellenic Center for Marine Research, Institute of Marine Biological Resources and Inland Waters, Anavissos Attikis, Greece
| | | | - Leo Posthuma
- Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University, Nijmegen, The Netherlands
- Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | | | - Christian K Feld
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
- Centre for Water and Environmental Research, University of Duisburg-Essen, Essen, Germany
| | - Judith Mahnkopf
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Berlin, Germany
| | - Daniel Hering
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
- Centre for Water and Environmental Research, University of Duisburg-Essen, Essen, Germany
| | - Sebastian Birk
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
- Centre for Water and Environmental Research, University of Duisburg-Essen, Essen, Germany
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16
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Lemm JU, Venohr M, Globevnik L, Stefanidis K, Panagopoulos Y, van Gils J, Posthuma L, Kristensen P, Feld CK, Mahnkopf J, Hering D, Birk S. Multiple stressors determine river ecological status at the European scale: Towards an integrated understanding of river status deterioration. Glob Chang Biol 2021. [PMID: 33372367 DOI: 10.1111/gch.15504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The biota of European rivers are affected by a wide range of stressors impairing water quality and hydro-morphology. Only about 40% of Europe's rivers reach 'good ecological status', a target set by the European Water Framework Directive (WFD) and indicated by the biota. It is yet unknown how the different stressors in concert impact ecological status and how the relationship between stressors and status differs between river types. We linked the intensity of seven stressors to recently measured ecological status data for more than 50,000 sub-catchment units (covering almost 80% of Europe's surface area), which were distributed among 12 broad river types. Stressor data were either derived from remote sensing data (extent of urban and agricultural land use in the riparian zone) or modelled (alteration of mean annual flow and of base flow, total phosphorous load, total nitrogen load and mixture toxic pressure, a composite metric for toxic substances), while data on ecological status were taken from national statutory reporting of the second WFD River Basin Management Plans for the years 2010-2015. We used Boosted Regression Trees to link ecological status to stressor intensities. The stressors explained on average 61% of deviance in ecological status for the 12 individual river types, with all seven stressors contributing considerably to this explanation. On average, 39.4% of the deviance was explained by altered hydro-morphology (morphology: 23.2%; hydrology: 16.2%), 34.4% by nutrient enrichment and 26.2% by toxic substances. More than half of the total deviance was explained by stressor interaction, with nutrient enrichment and toxic substances interacting most frequently and strongly. Our results underline that the biota of all European river types are determined by co-occurring and interacting multiple stressors, lending support to the conclusion that fundamental management strategies at the catchment scale are required to reach the ambitious objective of good ecological status of surface waters.
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Affiliation(s)
- Jan U Lemm
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
| | - Markus Venohr
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Berlin, Germany
| | - Lidija Globevnik
- Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, Slovenia
- TC Vode, Ljubljana, Slovenia
| | - Kostas Stefanidis
- Center for Hydrology and Informatics, National Technical University of Athens, Athens, Greece
- Hellenic Center for Marine Research, Institute of Marine Biological Resources and Inland Waters, Anavissos Attikis, Greece
| | - Yiannis Panagopoulos
- Center for Hydrology and Informatics, National Technical University of Athens, Athens, Greece
- Hellenic Center for Marine Research, Institute of Marine Biological Resources and Inland Waters, Anavissos Attikis, Greece
| | | | - Leo Posthuma
- Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University, Nijmegen, The Netherlands
- Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | | | - Christian K Feld
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
- Centre for Water and Environmental Research, University of Duisburg-Essen, Essen, Germany
| | - Judith Mahnkopf
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin, Berlin, Germany
| | - Daniel Hering
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
- Centre for Water and Environmental Research, University of Duisburg-Essen, Essen, Germany
| | - Sebastian Birk
- Faculty of Biology, Aquatic Ecology, University of Duisburg-Essen, Essen, Germany
- Centre for Water and Environmental Research, University of Duisburg-Essen, Essen, Germany
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17
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18
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Lyche Solheim A, Globevnik L, Austnes K, Kristensen P, Moe SJ, Persson J, Phillips G, Poikane S, van de Bund W, Birk S. A new broad typology for rivers and lakes in Europe: Development and application for large-scale environmental assessments. Sci Total Environ 2019; 697:134043. [PMID: 32380597 DOI: 10.1016/j.scitotenv.2019.134043] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 08/20/2019] [Accepted: 08/21/2019] [Indexed: 06/11/2023]
Abstract
European countries have defined >1000 national river types and >400 national lake types to implement the EU Water Framework Directive (WFD). In addition, common river and lake types have been defined within regions of Europe for intercalibrating the national classification systems for ecological status of water bodies. However, only a low proportion of national types correspond to these common intercalibration types. This causes uncertainty concerning whether the classification of ecological status is consistent across countries. Therefore, through an extensive dialogue with and data provision from all EU countries, we have developed a generic typology for European rivers and lakes. This new broad typology reflects the natural variability in the most commonly used environmental type descriptors: altitude, size and geology, as well as mean depth for lakes. These broad types capture 60-70% of all national WFD types including almost 80% of all European river and lake water bodies in almost all EU countries and can also be linked to all the common intercalibration types. The typology provides a new framework for large-scale assessments across country borders, as demonstrated with an assessment of ecological status and pressures based on European data from the 2nd set of river basin management plans. The typology can also be used for a variety of other large-scale assessments, such as reviewing and linking the water body types to habitat types under the Habitats Directive and the European Nature Information System (EUNIS), as well as comparing type-specific limit values for nutrients and other supporting quality elements across countries. Thus, the broad typology can build the basis for all scientific outputs of managerial relevance related to water body types.
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Affiliation(s)
- Anne Lyche Solheim
- Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, 0349 Oslo, Norway.
| | - Lidija Globevnik
- University of Ljubljana, Faculty of Civil and Geodetic Engineering, 1000 Ljubljana, Slovenia
| | - Kari Austnes
- Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, 0349 Oslo, Norway
| | - Peter Kristensen
- European Environment Agency (EEA), Kongens Nytorv, Copenhagen, Denmark
| | - S Jannicke Moe
- Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, 0349 Oslo, Norway
| | - Jonas Persson
- Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, 0349 Oslo, Norway
| | - Geoff Phillips
- School of Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, UK
| | - Sandra Poikane
- European Commission, Joint Research Centre (JRC), I-21027 Ispra, Italy
| | | | - Sebastian Birk
- University of Duisburg-Essen, Faculty of Biology, Aquatic Ecology, Universitätsstraße 5, 45141 Essen, Germany
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19
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Eser BE, Poborsky M, Dai R, Kishino S, Ljubic A, Takeuchi M, Jacobsen C, Ogawa J, Kristensen P, Guo Z. Rational Engineering of Hydratase from
Lactobacillus acidophilus
Reveals Critical Residues Directing Substrate Specificity and Regioselectivity. Chembiochem 2019; 21:550-563. [DOI: 10.1002/cbic.201900389] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Bekir Engin Eser
- Department of EngineeringAarhus University Gustav Wieds Vej 10 8000 Aarhus Denmark
| | - Michal Poborsky
- Department of EngineeringAarhus University Gustav Wieds Vej 10 8000 Aarhus Denmark
| | - Rongrong Dai
- Department of EngineeringAarhus University Gustav Wieds Vej 10 8000 Aarhus Denmark
| | - Shigenobu Kishino
- Division of Applied Life SciencesGraduate School of AgricultureKyoto University Kitashirakawa-oiwakecho Sakyo-ku Kyoto 606-8502 Japan
| | - Anita Ljubic
- Division of Food Technology, National Food InstituteTechnical University of Denmark Kemitorvet, Building 202 2800 Kgs. Lyngby Denmark
| | - Michiki Takeuchi
- Division of Applied Life SciencesGraduate School of AgricultureKyoto University Kitashirakawa-oiwakecho Sakyo-ku Kyoto 606-8502 Japan
| | - Charlotte Jacobsen
- Division of Food Technology, National Food InstituteTechnical University of Denmark Kemitorvet, Building 202 2800 Kgs. Lyngby Denmark
| | - Jun Ogawa
- Division of Applied Life SciencesGraduate School of AgricultureKyoto University Kitashirakawa-oiwakecho Sakyo-ku Kyoto 606-8502 Japan
| | - Peter Kristensen
- Faculty of Engineering and ScienceDepartment of Chemistry and BioscienceAalborg University Frederik Bayers Vej 7H 9220 Aalborg Denmark
| | - Zheng Guo
- Department of EngineeringAarhus University Gustav Wieds Vej 10 8000 Aarhus Denmark
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20
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Kold-Christensen R, Jensen KK, Smedegård-Holmquist E, Sørensen LK, Hansen J, Jørgensen KA, Kristensen P, Johannsen M. ReactELISA method for quantifying methylglyoxal levels in plasma and cell cultures. Redox Biol 2019; 26:101252. [PMID: 31254735 PMCID: PMC6604041 DOI: 10.1016/j.redox.2019.101252] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/31/2019] [Accepted: 06/08/2019] [Indexed: 01/14/2023] Open
Abstract
Methylglyoxal (MG) is a toxic glycolytic by-product associated with increased levels of inflammation and oxidative stress and has been linked to ageing-related diseases, such as diabetes and Alzheimer's disease. As MG is a highly reactive dicarbonyl compound, forming both reversible and irreversible adducts with a range of endogenous nucleophiles, measuring endogenous levels of MG are quite troublesome. Furthermore, as MG is a small metabolite it is not very immunogenic, excluding conventional ELISA for detection purposes, thus only more instrumentally demanding LC-MS/MS-based methods have demonstrated convincing quantitative data. In the present work we develop a novel bifunctional MG capture probe as well as a high specificity monoclonal antibody to finally setup a robust reaction-based ELISA (ReactELISA) method for detecting the highly reactive and low-level (nM) metabolite MG in human biological specimens. The assay is tested and validated against the current golden standard LC-MS/MS method in human blood plasma and cell-culture media. Furthermore, we demonstrate the assays ability to measure small perturbations of MG levels in growth media caused by a small molecule drug buthionine sulfoximine (BSO) of current clinical relevance. Finally, the assay is converted into a homogenous (no-wash) AlphaLISA version (ReactAlphaLISA), which offers the potential for operationally simple screening of further small molecules capable of perturbing cellular MG. Such compounds could be of relevance as probes to gain insight into MG metabolism as well as drug-leads to alleviate ageing-related diseases. MG is challenging to quantify, here we present a simple and specific ReactELISA based approach and validate against LC-MS/MS. Sensitivity at low (nM) endogenous concentration in both human blood plasma and cell culture media. Impact of BSO treatment of HEK293 cells can be profiled in culture media. Potential use in cell-based phenotypic screen for small molecules modulating MG metabolism.
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Affiliation(s)
- Rasmus Kold-Christensen
- Department of Forensic Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Karina Kragh Jensen
- Department of Forensic Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Emil Smedegård-Holmquist
- Department of Forensic Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | | | - Jakob Hansen
- Department of Forensic Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Karl Anker Jørgensen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Peter Kristensen
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Mogens Johannsen
- Department of Forensic Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
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21
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Prabhakar G, Gregg P, Rishoj L, Kristensen P, Ramachandran S. Octave-wide supercontinuum generation of light-carrying orbital angular momentum. Opt Express 2019; 27:11547-11556. [PMID: 31052998 DOI: 10.1364/oe.27.011547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/04/2019] [Indexed: 06/09/2023]
Abstract
Nonlinear frequency generation of light-carrying orbital angular momentum (OAM), which facilitates realization of on-demand, frequency-diverse optical vortices, would have utility in fields such as super-resolution microscopy, space-division multiplexing and quantum hyper-entanglement. In bulk media, OAM beams primarily differ in spatial phase, so the nonlinear overlap integral for self-phase matched χ(3) processes remains the same across the 4-fold degenerate subspace of beams (formed by different combinations of spin and orbital angular momentum) carrying the same OAM magnitude. This indistinguishable nature of nonlinear coupling implies that supercontinuum generation, which substantially relies on self/cross-phase modulation, and Raman soliton shifting of ultrashort pulses typically results in multimode outputs that do not conserve OAM. Here, using specially designed optical fibers that support OAM modes whose group velocity can be tailored, we demonstrate Raman solitons in OAM modes as well as the first supercontinuum spanning more than an octave (630 nm to 1430 nm), with the entire spectrum in the same polarization as well as OAM state. This is fundamentally possible because spin-orbit interactions in suitably designed fibers lead to large effective index and group velocity splitting of modes, and this helps tailoring nonlinear mode selectivity such that all nonlinearly generated frequencies reside in modes with high spatial mode purity.
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22
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Zhou Y, Jones NC, Nedergaard Pedersen J, Pérez B, Vrønning Hoffmann S, Vang Petersen S, Skov Pedersen J, Perriman A, Kristensen P, Gao R, Guo Z. Insight into the Structure and Activity of Surface-Engineered Lipase Biofluids. Chembiochem 2019; 20:1266-1272. [PMID: 30624001 DOI: 10.1002/cbic.201800819] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Indexed: 11/07/2022]
Abstract
Despite a successful application of solvent-free liquid protein (biofluids) concept to a number of commercial enzymes, the technical advantages of enzyme biofluids as hyperthermal stable biocatalysts cannot be fully utilized as up to 90-99% of native activities are lost when enzymes were made into biofluids. With a two-step strategy (site-directed mutagenesis and synthesis of variant biofluids) on Bacillus subtilis lipase A (BsLA), we elucidated a strong dependency of structure and activity on the number and distribution of polymer surfactant binding sites on BsLA surface. Here, it is demonstrated that improved BsLA variants can be engineered via site-mutagenesis by a rational design, either with enhanced activity in aqueous solution in native form, or with improved physical property and increased activity in solvent-free system in the form of a protein liquid. This work answered some fundamental questions about the surface characteristics for construction of biofluids, useful for identifying new strategies for developing advantageous biocatalysts.
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Affiliation(s)
- Ye Zhou
- Key Laboratory for Molecular Enzymology and Engineering, Ministry of Education, School of Life Sciences, Jilin University, No. 2699, Qianjin Street, Changchun, 130012, China
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, Aarhus, 8000, Denmark
| | - Nykola C Jones
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus, 8000, Denmark
| | - Jannik Nedergaard Pedersen
- Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, Aarhus, 8000, Denmark
| | - Bianca Pérez
- Eknologisk institut, Kongsvang Allé 29, Aarhus, 8000, Denmark
| | - Søren Vrønning Hoffmann
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus, 8000, Denmark
| | - Steen Vang Petersen
- Department of Biomedicine, Aarhus University, Wilhelm Meyers Allé 4, Aarhus, 8000, Denmark
| | - Jan Skov Pedersen
- Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, Aarhus, 8000, Denmark
| | - Adam Perriman
- School of Cellular and Molecular Medicine, University of Bristol, University Walk, Bristol, BS8 1TS, UK
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Frederik Bayers Vej 7H, Aalborg, 9220, Denmark
| | - Renjun Gao
- Key Laboratory for Molecular Enzymology and Engineering, Ministry of Education, School of Life Sciences, Jilin University, No. 2699, Qianjin Street, Changchun, 130012, China
| | - Zheng Guo
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, Aarhus, 8000, Denmark
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23
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Yatime L, Merle NS, Hansen AG, Friis NA, Østergaard JA, Bjerre M, Roumenina LT, Thiel S, Kristensen P, Andersen GR. A Single-Domain Antibody Targeting Complement Component C5 Acts as a Selective Inhibitor of the Terminal Pathway of the Complement System and Thus Functionally Mimicks the C-Terminal Domain of the Staphylococcus aureus SSL7 Protein. Front Immunol 2018; 9:2822. [PMID: 30555486 PMCID: PMC6281825 DOI: 10.3389/fimmu.2018.02822] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 11/15/2018] [Indexed: 11/13/2022] Open
Abstract
The complement system is an efficient anti-microbial effector mechanism. On the other hand abnormal complement activation is involved in the pathogenesis of multiple inflammatory and hemolytic diseases. As general inhibition of the complement system may jeopardize patient health due to increased susceptibility to infections, the development of pathway-specific complement therapeutics has been a long-lasting goal over the last decades. In particular, pathogen mimicry has been considered as a promising approach for the design of selective anti-complement drugs. The C-terminal domain of staphylococcal superantigen-like protein 7 (SSL7), a protein secreted by Staphylococcus aureus, was recently found to be a specific inhibitor of the terminal pathway of the complement system, providing selective inhibition of cell lysis mediated by the membrane attack complex (MAC). We describe here the selection by phage display of a humanized single-domain antibody (sdAb) mimicking the C-terminal domain of SSL7. The antibody, called sdAb_E4, binds complement C5 with an affinity in the low micromolar range. Furthermore, sdAb_E4 induces selective inhibition of MAC-mediated lysis, allowing inhibition of red blood cell hemolysis and inhibition of complement deposition on apopto-necrotic cells, while maintaining efficient bactericidal activity of the complement terminal pathway. Finally, we present preliminary results indicating that sdAb_E4 may also be efficient in inhibiting hemolysis of erythrocytes from patients with paroxysmal nocturnal hemoglobinuria. Our data provide a proof of concept for the design of a selective MAC inhibitor capable of retaining complement bacteriolytic activity and this study opens up promising perspectives for the development of an sdAb_E4-derived therapeutics with application in the treatment of complement-mediated hemolytic disorders.
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Affiliation(s)
- Laure Yatime
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Nicolas S Merle
- Centre de Recherche des Cordeliers, INSERM, UMR_S 1138, Paris, France
| | | | - Niels Anton Friis
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.,Centre de Recherche des Cordeliers, INSERM, UMR_S 1138, Paris, France
| | - Jakob A Østergaard
- The Medical Research Laboratory, Department of Clinical Medicine, Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Mette Bjerre
- The Medical Research Laboratory, Department of Clinical Medicine, Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Lubka T Roumenina
- Centre de Recherche des Cordeliers, INSERM, UMR_S 1138, Paris, France
| | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Gregers R Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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24
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Kristensen P, Corbett K, Hanvold TN, Hoff R, Mehlum IS. Drug deaths after high school dropout: a cohort study based on Norwegian national registries. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky212.580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- P Kristensen
- National Institute of Occupational Health, Oslo, Norway
| | - K Corbett
- National Institute of Occupational Health, Oslo, Norway
| | - TN Hanvold
- National Institute of Occupational Health, Oslo, Norway
| | - R Hoff
- University of Oslo, Oslo, Norway
| | - IS Mehlum
- National Institute of Occupational Health, Oslo, Norway
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25
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Sejbaek CS, Pedersen J, Bay H, Ramlau-Hansen CH, Schlünssen V, Bonde JP, Kristensen P, Hougaard KS. Risk of sickness absence during pregnancy due to multiple work factors. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky212.282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- CS Sejbaek
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - J Pedersen
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - H Bay
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - CH Ramlau-Hansen
- Department of Public Health, Section for Epidemiology, Aarhus University, Aarhus, Denmark
| | - V Schlünssen
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - JP Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - P Kristensen
- Department of Occupational Medicine and Epidemiology, National Institute of Occupational Health, Oslo, Norway
| | - KS Hougaard
- National Research Centre for the Working Environment, Copenhagen, Denmark
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26
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Hanvold TN, Corbett K, Kristensen P, Mehlum IS. The impact of a national workplace intervention om sickness absence in Norway. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky218.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- TN Hanvold
- National Institute of Occupational Health, Oslo, Norway
| | - K Corbett
- National Institute of Occupational Health, Oslo, Norway
| | - P Kristensen
- National Institute of Occupational Health, Oslo, Norway
| | - IS Mehlum
- National Institute of Occupational Health, Oslo, Norway
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27
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Nielsen LS, Andreasen PA, Grøndahi-Hansen J, Huang JY, Kristensen P, Danø K. Monoclonal Antibodies to Human 54,000 Molecular Weight Plasminogen Activator Inhibitor from Fibrosarcoma Cells - Inhibitor Neutralization and One-Step Affinity Purification. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1661523] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryMouse monoclonal antibodies were derived against a plasminogen activator inhibitor with a mol.wt. of ∼54,000 (54 K) from the human fibrosarcoma cell line HT-1080. Screening for hybrids producing antibodies directed against the inhibitor was performed with enzyme-linked immunosorbent assay and SDS-polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblotting. Four clones of hybridomas producing IgG1 antibodies were further characterized. The inhibitor was purified ∼50-fold to homogeneity from conditioned cell culture fluid with a yield of ∼85% by a one-step procedure using Sepharose-conjugated monoclonal antibody. In the 125I-fibrin plate assay one of the antibodies neutralized the effect of the inhibitor on urokinase-type plasminogen activator. Two of the antibodies bound complexes between urokinase-type plasminogen activator and inhibitor while the remaining two antibodies did not. The antibodies could be used for immunocytochemical localization of the inhibitor in HT-1080 cells. All four antibodies cross-reacted with a plasminogen activator inhibitor derived from cultured human umbilical cord endothelial cells.
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Affiliation(s)
- L S Nielsen
- The Finsen Laboratory, Finsen Institute, and Laboratory of Tumor Biology, Institute of Pathology, University of Copenhagen, Copenhagen, Denmark
| | - P A Andreasen
- The Finsen Laboratory, Finsen Institute, and Laboratory of Tumor Biology, Institute of Pathology, University of Copenhagen, Copenhagen, Denmark
| | - J Grøndahi-Hansen
- The Finsen Laboratory, Finsen Institute, and Laboratory of Tumor Biology, Institute of Pathology, University of Copenhagen, Copenhagen, Denmark
| | - J Y Huang
- The Finsen Laboratory, Finsen Institute, and Laboratory of Tumor Biology, Institute of Pathology, University of Copenhagen, Copenhagen, Denmark
| | - P Kristensen
- The Finsen Laboratory, Finsen Institute, and Laboratory of Tumor Biology, Institute of Pathology, University of Copenhagen, Copenhagen, Denmark
| | - K Danø
- The Finsen Laboratory, Finsen Institute, and Laboratory of Tumor Biology, Institute of Pathology, University of Copenhagen, Copenhagen, Denmark
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28
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Cheng W, Zhang Z, Xu R, Cai P, Kristensen P, Chen M, Huang Y. Incorporation of bacteriophages in polycaprolactone/collagen fibers for antibacterial hemostatic dual-function. J Biomed Mater Res B Appl Biomater 2018; 106:2588-2595. [DOI: 10.1002/jbm.b.34075] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/18/2017] [Accepted: 12/29/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Weilu Cheng
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University; Aarhus C DK-8000 Denmark
- School of Chemistry and Chemical Engineering, State Key Laboratory of Urban Water Resource and Environment; Harbin Institute of Technology; Harbin 150001 China
- Center for Medical Device Evaluation; China Food and Drug Administration; Beijing 100081 China
| | - Zhongyang Zhang
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University; Aarhus C DK-8000 Denmark
| | - Ruodan Xu
- Department of Engineering; Aarhus University; Aarhus C DK-8000 Denmark
| | - Panpan Cai
- School of Chemistry and Chemical Engineering, State Key Laboratory of Urban Water Resource and Environment; Harbin Institute of Technology; Harbin 150001 China
| | - Peter Kristensen
- Department of Engineering; Aarhus University; Aarhus C DK-8000 Denmark
| | - Menglin Chen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University; Aarhus C DK-8000 Denmark
- Department of Engineering; Aarhus University; Aarhus C DK-8000 Denmark
| | - Yudong Huang
- School of Chemistry and Chemical Engineering, State Key Laboratory of Urban Water Resource and Environment; Harbin Institute of Technology; Harbin 150001 China
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29
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Jensen JP, Kristensen P, Jeppesen E. Relationships between nitrogen loading and in-lake nitrogen concentrations in shallow Danish lakes. ACTA ACUST UNITED AC 2017. [DOI: 10.1080/03680770.1989.11898721] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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30
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Lykkemark S, Mandrup OA, Jensen MB, Just J, Kristensen P. A novel excision selection method for isolation of antibodies binding antigens expressed specifically by rare cells in tissue sections. Nucleic Acids Res 2017; 45:e107. [PMID: 28369551 PMCID: PMC5499801 DOI: 10.1093/nar/gkx207] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 03/21/2017] [Indexed: 12/22/2022] Open
Abstract
There is a growing appreciation of single cell technologies to provide increased biological insight and allow development of improved therapeutics. The central dogma explains why single cell technologies is further advanced in studies targeting nucleic acids compared to proteins, as nucleic acid amplification makes experimental detection possible. Here we describe a novel method for single round phage display selection of antibody fragments from genetic libraries targeting antigens expressed by rare cells in tissue sections. We present and discuss the results of two selections of antibodies recognizing antigens expressed by perivascular cells surrounding capillaries located in a human brain section; with the aim of identifying biomarkers expressed by pericytes. The area targeted for selection was identified by a known biomarker and morphological appearance, however in situ hybridizations to nucleic acids can also be used for the identification of target cells. The antibody selections were performed directly on the tissue sections followed by excision of the target cells using a glass capillary attached to micromanipulation equipment. Antibodies bound to the target cells were characterized using ELISA, immunocytochemistry and immunohistochemistry. The described method will provide a valuable tool for the discovery of novel biomarkers on rare cells in all types of tissues.
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Affiliation(s)
- Simon Lykkemark
- Department of Clinical Medicine, Aarhus University, Nørrebrogade 44, 8000 Aarhus C, Denmark.,Sino-Danish Centre for Education and Research (SDC), Niels Jensens Vej 2, 8000 Aarhus C, Denmark
| | - Ole Aalund Mandrup
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Mads Bjørnkjær Jensen
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Jesper Just
- Department of Molecular Biology and Genetics, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Peter Kristensen
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
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31
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Raff E, Hramiak I, Mann JF, Frandsen KB, Daniels G, Kristensen P, Nauck M, Nissen S, Pocock S, Poulter N, Ravn LS, Rasmussen S, Steinberg W, Stockner M, Zinman B, Baeres F. Liraglutide and Renal Outcomes in Type 2 Diabetes: Results of the LEADER Trial. Can J Diabetes 2017. [DOI: 10.1016/j.jcjd.2017.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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32
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Keller JG, Tesauro C, Coletta A, Graversen AD, Ho YP, Kristensen P, Stougaard M, Knudsen BR. On-slide detection of enzymatic activities in selected single cells. Nanoscale 2017; 9:13546-13553. [PMID: 28872165 DOI: 10.1039/c7nr05125e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
With increasing recognition of the importance in addressing cell-to-cell heterogeneity for the understanding of complex biological systems, there is a growing need for assays capable of single cell analyses. In the current study, we describe the measurement of human topoisomerase I activity in single CD44 positive Caco2 cells specifically captured from a mixed population on glass slides, which were dual functionalized with anti-CD44-antibodies and specific DNA primers. On-slide lysis of captured CD44 positive cells, resulted in the release of human topoisomerase I, allowing the enzyme to circularize a specific linear DNA substrate added to the slides. The generated circles hybridized to the anchored DNA primers and acted as templates for a solid support rolling circle amplification reaction leading to the generation of long tandem repeat products that were detected at the single molecule level in a fluorescent microscope upon hybridization of fluorescent labelled probes. The on-slide detection system was demonstrated to be directly quantitative and specific towards CD44 positive cells. Moreover, it allowed reproducible detection of human topoisomerase I activity in single cells.
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Affiliation(s)
- Josephine Geertsen Keller
- Department of Molecular Biology and Genetics, C. F. Møllers Allé 3, Bldg. 1131, Aarhus University, 8000 Aarhus C, Denmark.
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33
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Just J, Lykkemark S, Nielsen CH, Roshenas AR, Drasbek KR, Petersen SV, Bek T, Kristensen P. Pericyte modulation by a functional antibody obtained by a novel single-cell selection strategy. Microcirculation 2017; 24. [DOI: 10.1111/micc.12365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/21/2017] [Indexed: 12/28/2022]
Affiliation(s)
- Jesper Just
- Department of Molecular Biology and Genetics; Aarhus University; Aarhus C Denmark
- Department of Clinical Medicine; Aarhus University; Aarhus C Denmark
| | - Simon Lykkemark
- Department of Clinical Medicine; Aarhus University; Aarhus C Denmark
- Sino-Danish Centre for Education and Research (SDC); Aarhus C Denmark
| | - Charlotte H. Nielsen
- Department of Molecular Biology and Genetics; Aarhus University; Aarhus C Denmark
| | - Ali R. Roshenas
- Department of Engineering; Aarhus University; Aarhus C Denmark
| | - Kim R. Drasbek
- Department of Clinical Medicine; Aarhus University; Aarhus C Denmark
| | | | - Toke Bek
- Department of Clinical Medicine; Aarhus University; Aarhus C Denmark
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34
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Jørgensen ML, Møller CK, Rasmussen L, Boisen L, Pedersen H, Kristensen P. An anti vimentin antibody promotes tube formation. Sci Rep 2017; 7:3576. [PMID: 28620205 PMCID: PMC5472577 DOI: 10.1038/s41598-017-03799-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 04/18/2017] [Indexed: 12/02/2022] Open
Abstract
In recent years, there has been an increasing appreciation of the importance of secreted and extracellular proteins that traditionally have been considered as intracellular components. Vimentin is a highly abundant intermediate filament protein, and its intracellular functions have been investigated in a large number of studies. Recently, however, vimentin has been shown to take part in significant processes outside the cell. Our understanding of the functions of extracellular vimentin is, however, limited. In this study we demonstrate that a vimentin specific antibody, obtained by phage antibody technology, promotes tube formation of endothelial cells in a 2D matrigel assay. By binding vimentin, the antibody increases the tube formation by 21% after 5 hours of incubation. Addition of the antibody directly to cultured endothelial cells does not influence endothelial cell migration or proliferation. The enhanced tube formation can be seen for up to 10 hours where after the effect decreases. It is shown that the antibody-binding site is located on the coil 2 domain of vimentin. To our knowledge this is the first study that demonstrates an enhanced tube formation by binding vimentin in a 2D matrigel assay under normoxic conditions.
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Affiliation(s)
| | - Carina Kjeldahl Møller
- Department of Molecular biology, Gustav Wieds Vej 10, Aarhus University, 8000, Aarhus C, Denmark
| | - Lasse Rasmussen
- Department of Molecular biology, Gustav Wieds Vej 10, Aarhus University, 8000, Aarhus C, Denmark
| | - Louise Boisen
- Department of Molecular biology, Gustav Wieds Vej 10, Aarhus University, 8000, Aarhus C, Denmark
| | - Henrik Pedersen
- Department of Engineering, Gustav Wieds Vej 10, Aarhus University, 8000, Aarhus C, Denmark
| | - Peter Kristensen
- Department of Engineering, Gustav Wieds Vej 10, Aarhus University, 8000, Aarhus C, Denmark.
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35
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Mann JF, Nauck MA, Jacob S, Lüdemann J, Brown-Frandsen K, Daniels GH, Kristensen P, Nissen SE, Pocock S, Poulter NR, Ravn LS, Rasmussen S, Steinberg WM, Stockner M, Zinman B, Bergenstal RM, Rieck M, Baeres FM, Marso SP, Buse JB. Liraglutid und renale Endpunkte bei Typ 2 Diabetes: Ergebnisse der LEADER Studie. DIABETOL STOFFWECHS 2017. [DOI: 10.1055/s-0037-1601747] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- JF Mann
- Friedrich Alexander Universität Erlangen, Abteilung Nephrologie, Erlangen, Germany
| | - MA Nauck
- Ruhr-University Bochum, St. Josef Hospital, Klinische Forschung, Abteilung Diabetologie, Medizinische Klinik I, Bochum, Germany
| | - S Jacob
- Praxis für Prävention und Therapie, Villingen-Schwenningen, Germany
| | - J Lüdemann
- Diabetes- und Fußzentrum 'diabetes falkensee', Falkensee, Germany
| | | | - GH Daniels
- Massachusetts General Hospital, Boston, United States
| | | | - SE Nissen
- Cleveland Clinic, Department of Cardiovascular Medicine, Cleveland, United States
| | - S Pocock
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - NR Poulter
- Imperial College London, London, United Kingdom
| | - LS Ravn
- Novo Nordisk A/S, Soeborg, Denmark
| | | | - WM Steinberg
- George Washington University Medical Center, Department of Medicine, Rockville, United States
| | | | - B Zinman
- University of Toronto, Mount Sinai Hospital, Sinai Centre for Diabetes, Toronto, Canada
| | - RM Bergenstal
- Park Nicollet Institute for Research and Education, International Diabetes Center, Minneapolis, United States
| | - M Rieck
- Novo Nordisk Pharma GmbH, Mainz, Germany
| | | | - SP Marso
- University of Texas Southwestern, Department of Internal Medicine, Dallas, United States
| | - JB Buse
- University of North Carolina, School of Medicine, Department of Medicine, Chapel Hill, United States
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36
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Holmquist EF, B Keiding U, Kold-Christensen R, Salomón T, Jørgensen KA, Kristensen P, Poulsen TB, Johannsen M. ReactELISA: Monitoring a Carbon Nucleophilic Metabolite by ELISA-a Study of Lipid Metabolism. Anal Chem 2017; 89:5066-5071. [PMID: 28376300 DOI: 10.1021/acs.analchem.7b00507] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We here present a conceptually novel reaction-based ELISA principle (ReactELISA) for quantitation of the carbon nucleophilic lipid metabolite acetoacetate. Key to the assay is the utilization of a highly chemoselective Friedländer reaction that captures and simultaneously stabilizes the nucleophilic metabolite directly in the biological matrix. By developing a bifunctional biotinylated capture probe, the Friedländer-acetoacetate adduct can be trapped and purified directly in streptavidin coated wells. Finally, we outline the selection and refinement of a highly selective recombinant antibody for specific adduct quantitation. The setup is very robust and, as we demonstrate via miniaturization for microplate format, amenable for screening of compounds or interventions that alter lipid metabolism in liver cell cultures. The assay-principle should be extendable to quantitation of other nucleophilic or electrophilic and perhaps even more reactive metabolites provided suitable capture probes and antibodies.
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Affiliation(s)
- Emil F Holmquist
- Department of Forensic Medicine, Aarhus University , Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.,Department of Chemistry, Aarhus University , Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Ulrik B Keiding
- Department of Forensic Medicine, Aarhus University , Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.,Department of Chemistry, Aarhus University , Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Rasmus Kold-Christensen
- Department of Forensic Medicine, Aarhus University , Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.,Department of Chemistry, Aarhus University , Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Trine Salomón
- Department of Forensic Medicine, Aarhus University , Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Karl Anker Jørgensen
- Department of Chemistry, Aarhus University , Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Peter Kristensen
- Department of Engineering, Aarhus University , Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Thomas B Poulsen
- Department of Chemistry, Aarhus University , Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Mogens Johannsen
- Department of Forensic Medicine, Aarhus University , Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
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Sørensen KMJ, Meldgaard T, Melchjorsen CJ, Fridriksdottir AJ, Pedersen H, Petersen OW, Kristensen P. Upregulation of Mrps18a in breast cancer identified by selecting phage antibody libraries on breast tissue sections. BMC Cancer 2017; 17:19. [PMID: 28056857 PMCID: PMC5376696 DOI: 10.1186/s12885-016-2987-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 12/09/2016] [Indexed: 12/04/2022] Open
Abstract
Background One of the hallmarks of cancer is an altered energy metabolism, and here, mitochondria play a central role. Previous studies have indicated that some mitochondrial ribosomal proteins change their expression patterns upon transformation. Method In this study, we have used the selection of recombinant antibody libraries displayed on the surface of filamentous bacteriophage as a proteomics discovery tool for the identification of breast cancer biomarkers. A small subpopulation of breast cells expressing both cytokeratin 19 and cytokeratin 14 was targeted using a novel selection procedure. Results We identified the mitochondrial ribosomal protein s18a (Mrps18a) as a protein which is upregulated in breast cancer. However, Mrps18a was not homogeneously upregulated in all cancer cells, suggesting the existence of sub-populations within the tumor. The upregulation was not confined to cytokeratin 19 and cytokeratin 14 double positive cells. Conclusion This study illustrates how phage display can be applied towards the discovery of proteins which exhibit changes in their expression patterns. We identified the mitochondrial protein Mrps18a as being upregulated in human breast cancer cells compared to normal breast cells. Electronic supplementary material The online version of this article (doi:10.1186/s12885-016-2987-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Theresa Meldgaard
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Aarhus, Denmark
| | | | - Agla J Fridriksdottir
- Department of Cellular and Molecular Medicine, Centre for Biological Disease Analysis and Danish Stem Cell Centre, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Pedersen
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Aarhus, Denmark
| | - Ole William Petersen
- Department of Cellular and Molecular Medicine, Centre for Biological Disease Analysis and Danish Stem Cell Centre, University of Copenhagen, Copenhagen, Denmark
| | - Peter Kristensen
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Aarhus, Denmark.
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Abstract
BACKGROUND Associations between shift work (SW) schedules, mental distress and job satisfaction have never been completely described. AIMS To examine gender-specific associations of SW with mental distress and job satisfaction in nurses in Hebron District, Palestine, in 2012. METHODS Detailed information on work schedules (day versus shift), socio-demographic status, mental distress (General Health Questionnaire, GHQ-30) and job satisfaction (Generic Job Satisfaction Scale) in nurses employed in Hebron District, Palestine, was obtained through a questionnaire survey. Associations of SW and outcomes were examined by linear regression analysis. RESULTS Of 372 nurses eligible for the study, 309 and 338 completed surveys regarding mental distress and job satisfaction, respectively. The sample comprised 62% women and 38% men. After adjusting for covariates, women working shifts reported significantly higher levels of mean mental distress [β coefficient 3.6; 95% confidence interval (CI) 0.3-7.0] compared with women working regular day shifts. Men working shifts reported significantly lower levels of job satisfaction (-3.3; 95% CI -6.2 to -0.5) than men working regular day shifts. Women reported higher levels of mental distress than men, but this was unrelated to work schedule. CONCLUSIONS In this study, nurses working shifts reported higher levels of mental distress and lower levels of job satisfaction, although these associations were weaker when adjusted for potential covariates. There was no evidence of a gender differential in the association between SW and mental distress and job satisfaction.
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Affiliation(s)
- Y M Jaradat
- Department of Occupational Medicine and Epidemiology, National Institute of Occupational Health, Oslo 0033, Norway, .,Section for Preventive Medicine and Epidemiology, Institute of Health and Society, University of Oslo, Oslo 0316, Norway
| | - M B Nielsen
- Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo 0033, Norway
| | - P Kristensen
- Department of Occupational Medicine and Epidemiology, National Institute of Occupational Health, Oslo 0033, Norway
| | - R Bast-Pettersen
- Department of Occupational Medicine and Epidemiology, National Institute of Occupational Health, Oslo 0033, Norway
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Marso SP, Daniels GH, Brown-Frandsen K, Kristensen P, Mann JFE, Nauck MA, Nissen SE, Pocock S, Poulter NR, Ravn LS, Steinberg WM, Stockner M, Zinman B, Bergenstal RM, Buse JB. Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes. N Engl J Med 2016; 375:311-22. [PMID: 27295427 PMCID: PMC4985288 DOI: 10.1056/nejmoa1603827] [Citation(s) in RCA: 4200] [Impact Index Per Article: 525.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The cardiovascular effect of liraglutide, a glucagon-like peptide 1 analogue, when added to standard care in patients with type 2 diabetes, remains unknown. METHODS In this double-blind trial, we randomly assigned patients with type 2 diabetes and high cardiovascular risk to receive liraglutide or placebo. The primary composite outcome in the time-to-event analysis was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The primary hypothesis was that liraglutide would be noninferior to placebo with regard to the primary outcome, with a margin of 1.30 for the upper boundary of the 95% confidence interval of the hazard ratio. No adjustments for multiplicity were performed for the prespecified exploratory outcomes. RESULTS A total of 9340 patients underwent randomization. The median follow-up was 3.8 years. The primary outcome occurred in significantly fewer patients in the liraglutide group (608 of 4668 patients [13.0%]) than in the placebo group (694 of 4672 [14.9%]) (hazard ratio, 0.87; 95% confidence interval [CI], 0.78 to 0.97; P<0.001 for noninferiority; P=0.01 for superiority). Fewer patients died from cardiovascular causes in the liraglutide group (219 patients [4.7%]) than in the placebo group (278 [6.0%]) (hazard ratio, 0.78; 95% CI, 0.66 to 0.93; P=0.007). The rate of death from any cause was lower in the liraglutide group (381 patients [8.2%]) than in the placebo group (447 [9.6%]) (hazard ratio, 0.85; 95% CI, 0.74 to 0.97; P=0.02). The rates of nonfatal myocardial infarction, nonfatal stroke, and hospitalization for heart failure were nonsignificantly lower in the liraglutide group than in the placebo group. The most common adverse events leading to the discontinuation of liraglutide were gastrointestinal events. The incidence of pancreatitis was nonsignificantly lower in the liraglutide group than in the placebo group. CONCLUSIONS In the time-to-event analysis, the rate of the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke among patients with type 2 diabetes mellitus was lower with liraglutide than with placebo. (Funded by Novo Nordisk and the National Institutes of Health; LEADER ClinicalTrials.gov number, NCT01179048.).
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Affiliation(s)
- Steven P Marso
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Gilbert H Daniels
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Kirstine Brown-Frandsen
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Peter Kristensen
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Johannes F E Mann
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Michael A Nauck
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Steven E Nissen
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Stuart Pocock
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Neil R Poulter
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Lasse S Ravn
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - William M Steinberg
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Mette Stockner
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Bernard Zinman
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Richard M Bergenstal
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - John B Buse
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
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Marso SP, Daniels GH, Brown-Frandsen K, Kristensen P, Mann JFE, Nauck MA, Nissen SE, Pocock S, Poulter NR, Ravn LS, Steinberg WM, Stockner M, Zinman B, Bergenstal RM, Buse JB. Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes. N Engl J Med 2016. [PMID: 27295427 DOI: 10.1056/nejmoa1603827}] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND The cardiovascular effect of liraglutide, a glucagon-like peptide 1 analogue, when added to standard care in patients with type 2 diabetes, remains unknown. METHODS In this double-blind trial, we randomly assigned patients with type 2 diabetes and high cardiovascular risk to receive liraglutide or placebo. The primary composite outcome in the time-to-event analysis was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The primary hypothesis was that liraglutide would be noninferior to placebo with regard to the primary outcome, with a margin of 1.30 for the upper boundary of the 95% confidence interval of the hazard ratio. No adjustments for multiplicity were performed for the prespecified exploratory outcomes. RESULTS A total of 9340 patients underwent randomization. The median follow-up was 3.8 years. The primary outcome occurred in significantly fewer patients in the liraglutide group (608 of 4668 patients [13.0%]) than in the placebo group (694 of 4672 [14.9%]) (hazard ratio, 0.87; 95% confidence interval [CI], 0.78 to 0.97; P<0.001 for noninferiority; P=0.01 for superiority). Fewer patients died from cardiovascular causes in the liraglutide group (219 patients [4.7%]) than in the placebo group (278 [6.0%]) (hazard ratio, 0.78; 95% CI, 0.66 to 0.93; P=0.007). The rate of death from any cause was lower in the liraglutide group (381 patients [8.2%]) than in the placebo group (447 [9.6%]) (hazard ratio, 0.85; 95% CI, 0.74 to 0.97; P=0.02). The rates of nonfatal myocardial infarction, nonfatal stroke, and hospitalization for heart failure were nonsignificantly lower in the liraglutide group than in the placebo group. The most common adverse events leading to the discontinuation of liraglutide were gastrointestinal events. The incidence of pancreatitis was nonsignificantly lower in the liraglutide group than in the placebo group. CONCLUSIONS In the time-to-event analysis, the rate of the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke among patients with type 2 diabetes mellitus was lower with liraglutide than with placebo. (Funded by Novo Nordisk and the National Institutes of Health; LEADER ClinicalTrials.gov number, NCT01179048.).
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Affiliation(s)
- Steven P Marso
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Gilbert H Daniels
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Kirstine Brown-Frandsen
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Peter Kristensen
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Johannes F E Mann
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Michael A Nauck
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Steven E Nissen
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Stuart Pocock
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Neil R Poulter
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Lasse S Ravn
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - William M Steinberg
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Mette Stockner
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Bernard Zinman
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - Richard M Bergenstal
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
| | - John B Buse
- From the University of Texas Southwestern Medical Center, Dallas (S.P.M.); Massachusetts General Hospital, Boston (G.H.D.); Novo Nordisk, Bagsvaerd, Denmark (K.B.-F., P.K., L.S.R., M.S.); Friedrich Alexander University of Erlangen, Erlangen (J.F.E.M.), and St. Josef Hospital, Ruhr University, Bochum (M.A.N.) - both in Germany; Cleveland Clinic, Cleveland (S.E.N.); London School of Hygiene and Tropical Medicine Medical Statistics Unit (S.P.) and Imperial College London (N.R.P.), London; George Washington University Medical Center, Washington, DC (W.M.S.); Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, University of Toronto, Toronto (B.Z.); International Diabetes Center at Park Nicollet, Minneapolis (R.M.B.); and the University of North Carolina School of Medicine, Chapel Hill (J.B.B.)
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Larsen SA, Meldgaard T, Fridriksdottir AJ, Lykkemark S, Poulsen PC, Overgaard LF, Petersen HB, Petersen OW, Kristensen P. Selection of a breast cancer subpopulation-specific antibody using phage display on tissue sections. Immunol Res 2016; 62:263-72. [PMID: 25963139 PMCID: PMC4469306 DOI: 10.1007/s12026-015-8657-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Breast cancer tumors are composed of heterogeneous cell populations. These populations display a high variance in morphology, growth and metastatic propensity. They respond differently to therapeutic interventions, and some may be more prone to cause recurrence. Studying individual subpopulations of breast cancer may provide crucial knowledge for the development of individualized therapy. However, this process is challenged by the availability of biomarkers able to identify subpopulations specifically. Here, we demonstrate an approach for phage display selection of recombinant antibody fragments on cryostat sections of human breast cancer tissue. This method allows for selection of recombinant antibodies binding to antigens specifically expressed in a small part of the tissue section. In this case, a CD271+ subpopulation of breast cancer cells was targeted, and these may be potential breast cancer stem cells. We isolated an antibody fragment LH 7, which in immunohistochemistry experiments demonstrates specific binding to breast cancer subpopulations. The selection of antibody fragments directly on small defined areas within a larger section of malignant tissue is a novel approach by which it is possible to better target cellular heterogeneity in proteomic studies. The identification of novel biomarkers is relevant for our understanding and intervention in human diseases. The selection of the breast cancer-specific antibody fragment LH 7 may reveal novel subpopulation-specific biomarkers, which has the potential to provide new insight and treatment strategies for breast cancer.
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Affiliation(s)
- Simon Asbjørn Larsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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Larsen SA, Meldgaard T, Fridriksdottir AJR, Lykkemark S, Poulsen PC, Overgaard LF, Petersen HB, Petersen OW, Kristensen P. Raising an Antibody Specific to Breast Cancer Subpopulations Using Phage Display on Tissue Sections. Cancer Genomics Proteomics 2016; 13:21-30. [PMID: 26708596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
BACKGROUND/AIM Primary tumors display a great level of intra-tumor heterogeneity in breast cancer. The current lack of prognostic and predictive biomarkers limits accurate stratification and the ability to predict response to therapy. The aim of the present study was to select recombinant antibody fragments specific against breast cancer subpopulations, aiding the discovery of novel biomarkers. MATERIALS AND METHODS Recombinant antibody fragments were selected by phage display. A novel shadowstick technology enabled the direct selection using tissue sections of antibody fragments specific against small subpopulations of breast cancer cells. Selections were performed against a subpopulation of breast cancer cells expressing CD271+, as these previously have been indicated to be potential breast cancer stem cells. The selected antibody fragments were screened by phage ELISA on both breast cancer and myoepithelial cells. The antibody fragments were validated and evaluated by immunohistochemistry experiments. RESULTS Our study revealed an antibody fragment, LH8, specific for breast cancer cells. Immunohistochemistry results indicate that this particular antibody fragment binds an antigen that exhibits differential expression in different breast cancer subpopulations. CONCLUSION Further studies characterizing this antibody fragment, the subpopulation it binds and the cognate antigen may unearth novel biomarkers of clinical relevance.
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Affiliation(s)
- Simon Asbjørn Larsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Agla Jael Rubner Fridriksdottir
- Department of Cellular and Molecular Medicine, Centre for Biological Disease Analysis and Danish Stem Cell Centre, University of Copenhagen, Copenhagen, Denmark
| | - Simon Lykkemark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark Sino-Danish Centre for Education and Research (SDC), Aarhus, Denmark
| | | | | | | | - Ole William Petersen
- Department of Cellular and Molecular Medicine, Centre for Biological Disease Analysis and Danish Stem Cell Centre, University of Copenhagen, Copenhagen, Denmark
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43
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Just J, Jung T, Friis NA, Lykkemark S, Drasbek K, Siboska G, Grune T, Kristensen P. Identification of an unstable 4-hydroxynoneal modification on the 20S proteasome subunit α7 by recombinant antibody technology. Free Radic Biol Med 2015; 89:786-92. [PMID: 26472192 DOI: 10.1016/j.freeradbiomed.2015.10.405] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 09/07/2015] [Accepted: 10/08/2015] [Indexed: 11/29/2022]
Abstract
Numerous cellular functions rely on an active proteasome allowing degradation of damaged or misfolded proteins. Therefore changes in the proteasomal activity have important physiological consequences. During oxidative stress the production of free radicals can result in the formation of 4-hydroxynonenal (HNE) following lipid peroxidiation. The HNE moiety is highly reactive and via a nucleophilic attack readily forms covalent links to cysteine, histidine and lysine side chains. However, as the chemical properties of these amino acids differ, so does the kinetics of the reactions. While covalent linkage through Michael addition is well established, reversible and unstable associations have only been indicated in a few cases. In the present study we have identified an unstable HNE adduct on the α7 subunit of the 20S proteasome using phage display of recombinant antibodies. This recombinant antibody fragment recognized HNE modified proteasomes in vitro and showed that this epitope was easily HNE modified, yet unstable, and influenced by experimental procedures. Hence unstable HNE-adducts could be overlooked as a regulatory mechanism of proteasomal activity and a participating factor in the decreased proteasomal activity associated with oxidative stress.
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Affiliation(s)
- Jesper Just
- Aarhus University, Department of Molecular Biology and Genetics, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Tobias Jung
- German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany
| | - Niels Anton Friis
- Aarhus University, Department of Molecular Biology and Genetics, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Simon Lykkemark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Sino-Danish Centre for Education and Research (SDC), Aarhus, Denmark
| | - Kim Drasbek
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Gunhild Siboska
- Aarhus University, Department of Molecular Biology and Genetics, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Tilman Grune
- German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany
| | - Peter Kristensen
- Aarthus Univeristy, Department of Engineering, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark.
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Larsen SA, Meldgaard T, Lykkemark S, Mandrup OA, Kristensen P. Selection of cell-type specific antibodies on tissue-sections using phage display. J Cell Mol Med 2015; 19:1939-48. [PMID: 25808085 PMCID: PMC4549044 DOI: 10.1111/jcmm.12568] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/29/2015] [Indexed: 12/29/2022] Open
Abstract
With the advent of modern technologies enabling single cell analysis, it has become clear that small sub-populations of cells or even single cells can drive the phenotypic appearance of tissue, both diseased and normal. Nucleic acid based technologies allowing single cell analysis has been faster to mature, while technologies aimed at analysing the proteome at a single cell level is still lacking behind, especially technologies which allow single cell analysis in tissue. Introducing methods, that allows such analysis, will pave the way for discovering new biomarkers with more clinical relevance, as these may be unique for microenvironments only present in tissue and will avoid artifacts introduced by in vitro studies. Here, we introduce a technology enabling biomarker identification on small sub-populations of cells within a tissue section. Phage antibody libraries are applied to the tissue sections, followed by washing to remove non-bound phage particles. To eliminate phage antibodies binding to antigens ubiquitously expressed and retrieve phage antibodies binding specifically to antigens expressed by the sub-population of cells, the area of interest is protected by a ‘shadow stick’. The phage antibodies on the remaining areas on the slide are exposed to UV light, which introduces cross-links in the phage genome, thus rendering them non-replicable. In this work we applied the technology, guided by CD31 expressing endothelial cells, to isolate recombinant antibodies specifically binding biomarkers expressed either by the cell or in the microenvironment surrounding the endothelial cell.
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Affiliation(s)
- Simon Asbjørn Larsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Simon Lykkemark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Sino-Danish Centre for Education and Research (SDC), Aarhus, Denmark
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Bürkle A, Moreno-Villanueva M, Bernhard J, Blasco M, Zondag G, Hoeijmakers JHJ, Toussaint O, Grubeck-Loebenstein B, Mocchegiani E, Collino S, Gonos ES, Sikora E, Gradinaru D, Dollé M, Salmon M, Kristensen P, Griffiths HR, Libert C, Grune T, Breusing N, Simm A, Franceschi C, Capri M, Talbot D, Caiafa P, Friguet B, Slagboom PE, Hervonen A, Hurme M, Aspinall R. MARK-AGE biomarkers of ageing. Mech Ageing Dev 2015; 151:2-12. [PMID: 25818235 DOI: 10.1016/j.mad.2015.03.006] [Citation(s) in RCA: 156] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/19/2015] [Accepted: 03/21/2015] [Indexed: 01/29/2023]
Abstract
Many candidate biomarkers of human ageing have been proposed in the scientific literature but in all cases their variability in cross-sectional studies is considerable, and therefore no single measurement has proven to serve a useful marker to determine, on its own, biological age. A plausible reason for this is the intrinsic multi-causal and multi-system nature of the ageing process. The recently completed MARK-AGE study was a large-scale integrated project supported by the European Commission. The major aim of this project was to conduct a population study comprising about 3200 subjects in order to identify a set of biomarkers of ageing which, as a combination of parameters with appropriate weighting, would measure biological age better than any marker in isolation.
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Affiliation(s)
- Alexander Bürkle
- Molecular Toxicology Group, Department of Biology, Box 628, University of Konstanz, 78457 Konstanz, Germany.
| | - María Moreno-Villanueva
- Molecular Toxicology Group, Department of Biology, Box 628, University of Konstanz, 78457 Konstanz, Germany
| | | | - María Blasco
- Spanish National Cancer Research Centre (CNIO), 3 Melchor Fernandez Almagro, 28029 Madrid, Spain
| | | | - Jan H J Hoeijmakers
- Department of Genetics, Erasmus University Medical Center, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
| | - Olivier Toussaint
- University of Namur, Research Unit on Cellular Biology, Rue de Bruxelles, 61, Namur B-5000, Belgium
| | - Beatrix Grubeck-Loebenstein
- Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg, 10, 6020 Innsbruck, Austria
| | - Eugenio Mocchegiani
- Translational Research Center of Nutrition and Ageing, IRCCS-INRCA, Via Birarelli 8, 60121 Ancona, Italy
| | - Sebastiano Collino
- Nestlé Institute of Health Sciences SA, Molecular Biomarkers, EPFL Innovation Park, 1015 Lausanne, Switzerland
| | - Efstathios S Gonos
- National Hellenic Research Foundation, Institute of Biology, Medicinal Chemistry and Biotechnology, Athens, Greece
| | - Ewa Sikora
- Laboratory of the Molecular Bases of Ageing, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur street, 02-093 Warsaw, Poland
| | - Daniela Gradinaru
- Ana Aslan - National Institute of Gerontology and Geriatrics, Bucharest, Romania
| | - Martijn Dollé
- National Institute for Public Health and the Environment (RIVM), Centre for Prevention and Health Services Research, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
| | - Michel Salmon
- Straticell, Science Park Crealys, Rue Jean Sonet 10, 5032 Les Isnes, Belgium
| | - Peter Kristensen
- Department of Engineering - BCE Protein Engineering, Gustav Wiedsvej 10, 8000 Aarhus, Denmark
| | - Helen R Griffiths
- Life and Health Sciences, Aston Research Centre for Healthy Ageing, Aston University, Birmingham, UK
| | - Claude Libert
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
| | - Tilman Grune
- Institute of Nutritional Medicine, University of Hohenheim, 70593 Stuttgart, Germany; Department of Nutritional Toxicology, Friedrich Schiller University Jena, Dornburger Str. 24, 07743 Jena, Germany
| | - Nicolle Breusing
- Institute of Nutritional Medicine, University of Hohenheim, 70593 Stuttgart, Germany
| | - Andreas Simm
- Department of Cardiothoracic Surgery, University Hospital Halle, Ernst-Grube Str. 40, 06120 Halle (Saale), Germany
| | - Claudio Franceschi
- CIG-Interdepartmental Center "L.Galvani", Alma Mater Studiorum, University of Bologna, 40126 Bologna, Italy
| | - Miriam Capri
- CIG-Interdepartmental Center "L.Galvani", Alma Mater Studiorum, University of Bologna, 40126 Bologna, Italy
| | | | - Paola Caiafa
- Department of Cellular Biotechnologies and Hematology, Faculty of Pharmacy and Medicine, "Sapienza" University Rome, V.le Regina Elena 324, 00161 Rome, Italy
| | - Bertrand Friguet
- Sorbonne Universités, UPMC Univ Paris 06, UMR UPMC CNRS 8256, Biological adaptation and ageing - IBPS, INSERM U1164, F-75005 Paris, France
| | - P Eline Slagboom
- Department of Molecular Epidemiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Antti Hervonen
- Medical School, University of Tampere, 33014 Tampere, Finland
| | - Mikko Hurme
- Medical School, University of Tampere, 33014 Tampere, Finland
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Ramachandran S, Gregg P, Kristensen P, Golowich SE. On the scalability of ring fiber designs for OAM multiplexing. Opt Express 2015; 23:3721-3730. [PMID: 25836225 DOI: 10.1364/oe.23.003721] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The promise of the infinite-dimensionality of orbital angular momentum (OAM) and its application to free-space and fiber communications has attracted immense attention in recent years. In order to facilitate OAM-guidance, novel fibers have been proposed and developed, including a class of so-called ring-fibers. In these fibers, the wave-guiding region is a high-index annulus instead of a conventional circular core, which for reasons related to polarization-dependent differential phase shifts for light at waveguide boundaries, leads to enhanced stability for OAM modes. We review the theory and implementation of this nascent class of waveguides, and discuss the opportunities and limitations they present for OAM scalability.
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47
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Zheng M, Rangan A, Olsen NJ, Andersen LB, Wedderkopp N, Kristensen P, Grøntved A, Ried-Larsen M, Lempert SM, Allman-Farinelli M, Heitmann BL. Substituting sugar-sweetened beverages with water or milk is inversely associated with body fatness development from childhood to adolescence. Nutrition 2015; 31:38-44. [DOI: 10.1016/j.nut.2014.04.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 04/01/2014] [Accepted: 04/09/2014] [Indexed: 10/25/2022]
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Bertelsen LB, Bohn AB, Smith M, Mølgaard B, Møller B, Stødkilde-Jørgensen H, Kristensen P. Are endothelial outgrowth cells a potential source for future re-vascularization therapy? Exp Gerontol 2014; 58:132-8. [DOI: 10.1016/j.exger.2014.07.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 07/25/2014] [Accepted: 07/31/2014] [Indexed: 01/02/2023]
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Raule N, Sevini F, Li S, Barbieri A, Tallaro F, Lomartire L, Vianello D, Montesanto A, Moilanen JS, Bezrukov V, Blanché H, Hervonen A, Christensen K, Deiana L, Gonos ES, Kirkwood TBL, Kristensen P, Leon A, Pelicci PG, Poulain M, Rea IM, Remacle J, Robine JM, Schreiber S, Sikora E, Eline Slagboom P, Spazzafumo L, Antonietta Stazi M, Toussaint O, Vaupel JW, Rose G, Majamaa K, Perola M, Johnson TE, Bolund L, Yang H, Passarino G, Franceschi C. The co-occurrence of mtDNA mutations on different oxidative phosphorylation subunits, not detected by haplogroup analysis, affects human longevity and is population specific. Aging Cell 2014; 13:401-7. [PMID: 24341918 PMCID: PMC4326891 DOI: 10.1111/acel.12186] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2013] [Indexed: 01/01/2023] Open
Abstract
To re-examine the correlation between mtDNA variability and longevity, we examined mtDNAs from samples obtained from over 2200 ultranonagenarians (and an equal number of controls) collected within the framework of the GEHA EU project. The samples were categorized by high-resolution classification, while about 1300 mtDNA molecules (650 ultranonagenarians and an equal number of controls) were completely sequenced. Sequences, unlike standard haplogroup analysis, made possible to evaluate for the first time the cumulative effects of specific, concomitant mtDNA mutations, including those that per se have a low, or very low, impact. In particular, the analysis of the mutations occurring in different OXPHOS complex showed a complex scenario with a different mutation burden in 90+ subjects with respect to controls. These findings suggested that mutations in subunits of the OXPHOS complex I had a beneficial effect on longevity, while the simultaneous presence of mutations in complex I and III (which also occurs in J subhaplogroups involved in LHON) and in complex I and V seemed to be detrimental, likely explaining previous contradictory results. On the whole, our study, which goes beyond haplogroup analysis, suggests that mitochondrial DNA variation does affect human longevity, but its effect is heavily influenced by the interaction between mutations concomitantly occurring on different mtDNA genes.
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Affiliation(s)
- Nicola Raule
- BioPhysics and Biocomplexity and Department of Experimental Pathology; C.I. G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics; University of Bologna; Bologna 40126 Italy
| | - Federica Sevini
- BioPhysics and Biocomplexity and Department of Experimental Pathology; C.I. G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics; University of Bologna; Bologna 40126 Italy
| | | | - Annalaura Barbieri
- BioPhysics and Biocomplexity and Department of Experimental Pathology; C.I. G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics; University of Bologna; Bologna 40126 Italy
| | - Federica Tallaro
- Department of Cell Biology; University of Calabria; Rende 87036 Italy
| | - Laura Lomartire
- BioPhysics and Biocomplexity and Department of Experimental Pathology; C.I. G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics; University of Bologna; Bologna 40126 Italy
| | - Dario Vianello
- BioPhysics and Biocomplexity and Department of Experimental Pathology; C.I. G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics; University of Bologna; Bologna 40126 Italy
| | | | - Jukka S. Moilanen
- Institute of Clinical Medicine; University of Oulu; Oulu University Hospital and MRC Oulu; Oulu 90014 Finland
| | | | - Hélène Blanché
- Centre Polymorphisme Humaine; Fondation Jean Dausset; Paris 75010 France
| | | | - Kaare Christensen
- Institute of Public Health; University of Southern Denmark; Odense 5230 Denmark
| | | | | | - Tom B. L. Kirkwood
- School of Clinical Medical Sciences; Gerontology “Henry Wellcome”; University of Newcastle upon Tyne; Newcastle upon Tyne NE1 3BZ UK
| | | | - Alberta Leon
- Research & Innovation Soc.Coop. a r.l.; Padova 35127 Italy
| | | | - Michel Poulain
- Research Centre of Demographic Management for Public Administrations; UCL-GéDAP; Louvain-la-Neuve 1348 Belgium
| | - Irene M. Rea
- The Queen's University Belfast; Belfast BT7 1NN UK
| | - Josè Remacle
- Eppendorf Array Technologies; SA-EAT Research and Development; Namur 5000 Belgium
| | - Jean Marie Robine
- University of Montpellier; Val d'Aurelle Cancer Research Center; Montpellier 34090 France
| | - Stefan Schreiber
- Kiel Center for Functional Genomics; University Hospital Schleswig Holstein; Kiel 24105 Germany
| | - Ewa Sikora
- Nencki Institute of Experimental Biology; Polish Academy of Sciences; Warsaw 00-679 Poland
| | | | - Liana Spazzafumo
- INRCA-Italian National Research Centre on Aging; Ancona 60127 Italy
| | | | | | - James W. Vaupel
- Max Planck Institute for Demographic Research; Rostock 18057 Germany
| | - Giuseppina Rose
- Department of Cell Biology; University of Calabria; Rende 87036 Italy
| | - Kari Majamaa
- Institute of Clinical Medicine; University of Oulu; Oulu University Hospital and MRC Oulu; Oulu 90014 Finland
| | - Markus Perola
- National Public Health Institute; Helsinki 00260 Finland
| | - Thomas E. Johnson
- Institute for Behavioral Genetics; University of Colorado Boulder; Boulder CO 80309 USA
| | | | | | | | - Claudio Franceschi
- BioPhysics and Biocomplexity and Department of Experimental Pathology; C.I. G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics; University of Bologna; Bologna 40126 Italy
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Jørgensen ML, Friis NA, Just J, Madsen P, Petersen SV, Kristensen P. Expression of single-chain variable fragments fused with the Fc-region of rabbit IgG in Leishmania tarentolae. Microb Cell Fact 2014; 13:9. [PMID: 24428896 PMCID: PMC3917567 DOI: 10.1186/1475-2859-13-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 01/04/2014] [Indexed: 12/03/2022] Open
Abstract
Background In recent years the generation of antibodies by recombinant methods, such as phage display technology, has increased the speed by which antibodies can be obtained. However, in some cases when recombinant antibodies have to be validated, expression in E. coli can be problematic. This primarily occurs when codon usage or protein folding of specific antibody fragments is incompatible with the E. coli translation and folding machinery, for instance when recombinant antibody formats that include the Fc-region are needed. In such cases other expression systems can be used, including the protozoan parasite Leishmania tarentolae (L. tarentolae). This novel host for recombinant protein expression has recently shown promising properties for the expression of single-chain antibody fragments. We have utilised the L. tarentolae T7-TR system to achieve expression and secretion of two scFvs fused to the Fc-region of rabbit immunoglobulin G (IgG). Results Based on the commercial vector pLEXSY_IE-blecherry4 (Jena Bioscience; Cat. No. EGE-255), we generated a vector containing the Fragment Crystallisable (Fc) region of rabbit IgG allowing insertions of single chain antibody fragments (scFvs) in frame via Ncol/Notl cloning (pMJ_LEXSY-rFc). For the expression of rabbit Fc-fusion scFvs (scFv-rFc) we cloned two scFvs binding to human vimentin (LOB7 scFv) and murine laminin (A10 scFv) respectively, into the modified vector. The LOB7-rFc and A10-rFc fusions expressed at levels up to 2.95 mg/L in L. tarentolae T7-TR. Both scFv-rFcs were purified from the culture supernatants using protein A affinity chromatography. Additionally, we expressed three different scFvs without the rFc regions using a similar expression cassette, obtaining yields up to 1.00 mg/L. Conclusions To our knowledge, this is the first time that antibody fragments with intact Fc-region of immunoglobulin have been produced in L. tarentolae. Using the plasmid pMJ_LEXSY-rFc, L. tarentolae T7-TR can be applied as an efficient tool for expression of rFc fusion antibody fragments, allowing easy purification from the growth medium. This system provides an alternative in cases where antibody constructs express poorly in standard prokaryotic systems. Furthermore, in cases where bivalent Fc-fused antibody constructs are needed, using L. tarentolae for expression provides an efficient alternative to mammalian expression.
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Affiliation(s)
| | | | | | | | | | - Peter Kristensen
- Department of Engineering, Aarhus University, Gustav Wieds Vej 10, Aarhus, Denmark.
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