1
|
Misra P, Tischer A, Lampe L, Pierluissi-Ruiz V, Dick CJ, Bragantini B, Kormshchikov N, Auton M, Ramirez-Alvarado M. Biophysical characterization of human-cell-expressed, full-length κI O18/O8, AL-09, λ6a, and Wil immunoglobulin light chains. Biochim Biophys Acta Proteins Proteom 2024; 1872:140993. [PMID: 38169170 PMCID: PMC10939777 DOI: 10.1016/j.bbapap.2023.140993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/12/2023] [Accepted: 12/29/2023] [Indexed: 01/05/2024]
Abstract
Immunoglobulin light chain (AL) amyloidosis involves the deposition of insoluble monoclonal AL protein fibrils in the extracellular space of different organs leading to dysfunction and death. Development of methods to efficiently express and purify AL proteins with acceptable standards of homogeneity and structural integrity has become critical to understand the in vitro and in vivo aspects of AL protein aggregation, and thus the disease progression. In this study, we report the biophysical characterization of His-tagged and untagged versions of AL full-length (FL) κI and λ6 subgroup proteins and their mutants expressed from the Expi293F human cell line. We used an array of biophysical and biochemical methods to analyze the structure and stability of the monomers, oligomerization states, and thermodynamic characteristics of the purified FL proteins and how they compare with the bacterially expressed FL proteins. Our results demonstrate that the tagged and untagged versions of FL proteins have comparable stability to proteins expressed in bacterial cells but exhibit multiple unfolding transitions and reversibility. Non-reducing SDS-PAGE and analytical ultracentrifugation analysis showed presence of monomers and dimers, with an insignificant amount of higher-order oligomers, in the purified fraction of all proteins. Overall, the FL proteins were expressed with sufficient yields for biophysical studies and can replace bacterial expression systems.
Collapse
Affiliation(s)
- Pinaki Misra
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
| | - Alexander Tischer
- Department of Hematology, Mayo Clinic, 200 First St SW, Rochester, MN, USA.
| | - Lindsey Lampe
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
| | - Valeria Pierluissi-Ruiz
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
| | - Christopher J Dick
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
| | - Benoit Bragantini
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
| | - Nikita Kormshchikov
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
| | - Matthew Auton
- Department of Hematology, Mayo Clinic, 200 First St SW, Rochester, MN, USA
| | - Marina Ramirez-Alvarado
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA; Department of Immunology, Mayo Clinic, 200 First St SW, Rochester, MN, USA.
| |
Collapse
|
2
|
Sumerskii I, Böhmdorfer S, Tsetsgee O, Sulaeva I, Khaliliyan H, Musl O, Dorninger K, Tischer A, Potthast K, Rosenau T, Brereton RG, Potthast A. Tapping the Full Potential of Infrared Spectroscopy for the Analysis of Technical Lignins. ChemSusChem 2024:e202301840. [PMID: 38240610 DOI: 10.1002/cssc.202301840] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/17/2024] [Indexed: 04/24/2024]
Abstract
We present an approach to overcome the challenges associated with the increasing demand of high-throughput characterization of technical lignins, a key resource in emerging bioeconomies. Our approach offers a resort from the lack of direct, simple, and low-cost analytical techniques for lignin characterization by employing multivariate calibration models based on infrared (IR) spectroscopy to predict structural properties of lignins (i. e., functionality, molar mass). By leveraging a comprehensive database of over 500 well-characterized technical lignin samples - a factor of 10 larger than previously used sets - our chemometric models achieved high levels of quality and statistical confidence for the determination of different functional group contents (RMSEPs of 4-16 %). However, the statistical moments of the molar mass distribution are still best determined by size-exclusion chromatography. Analyses of over 500 technical lignins offered also a great opportunity to provide information on the general variability in kraft lignins and lignosulfonates (from different origins). Overall, the effected savings in analysis time (>7 h), resources, and required sample mass combined with non-destructiveness of the measurement satisfy key demands for efficient high-throughput lignin analyses. Finally, we discuss the advantages, disadvantages, and limitations of our approach, along with critical insights into the associated chemical-analytical and spectroscopic challenges.
Collapse
Affiliation(s)
- Ivan Sumerskii
- Core Facility "Analysis of Lignocellulosics" (ALICE), BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Stefan Böhmdorfer
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Otgontuul Tsetsgee
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Irina Sulaeva
- Core Facility "Analysis of Lignocellulosics" (ALICE), BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Hajar Khaliliyan
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Oliver Musl
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Katharina Dorninger
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Alexander Tischer
- Department of Soil Science, Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Karin Potthast
- Department of Soil Science, Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Thomas Rosenau
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| | - Richard G Brereton
- School of Chemistry, University of Bristol, Cantocks Close, Bristol, BS8 1TS, U.K
| | - Antje Potthast
- Department of Chemistry, Institute of Chemistry of Renewable Resources, BOKU University, Vienna, Konrad-Lorenz-Strasse 24, A-3430, Tulln, Austria
| |
Collapse
|
3
|
Auton M, Tischer A. Wedging the door open on platelet-type von Willebrand disease. Br J Haematol 2023; 203:501-503. [PMID: 37666663 DOI: 10.1111/bjh.19094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 08/21/2023] [Accepted: 08/24/2023] [Indexed: 09/06/2023]
Affiliation(s)
- Matthew Auton
- Division of Hematology, Mayo Clinic, Rochester, Minnesota, USA
| | | |
Collapse
|
4
|
Putzenlechner B, Koal P, Kappas M, Löw M, Mundhenk P, Tischer A, Wernicke J, Koukal T. Towards precision forestry: Drought response from remote sensing-based disturbance monitoring and fine-scale soil information in Central Europe. Sci Total Environ 2023; 880:163114. [PMID: 37011694 DOI: 10.1016/j.scitotenv.2023.163114] [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] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/23/2023] [Accepted: 03/23/2023] [Indexed: 05/27/2023]
Abstract
Prolonged drought and susceptibility to biotic stressors induced an extensive calamity in Norway spruce (Picea abies (L.) Karst.) and widespread crown defoliation in European beech (Fagus sylvatica L.) in Central Europe. For future management decisions, it is crucial to link changes in canopy cover to site conditions. However, current knowledge on the role of soil properties for drought-induced forest disturbance is limited due to the scarcity and low spatial resolution of soil information. We present a fine-scale assessment on the role of soil properties for forest disturbance in Norway spruce and European beech derived from optical remote sensing. A forest disturbance modeling framework based on Sentinel-2 time series was applied on 340 km2 in low mountain ranges of Central Germany. Spatio-temporal information on forest disturbance was calculated at 10 m spatial resolution in the period 2019-2021 and intersected with high-resolution soil information (1:10,000) based on roughly 2850 soil profiles. We found distinct differences in disturbed area, depending on soil type, texture, stoniness, effective rooting depth and available water capacity (AWC). For spruce, we found a polynomial relationship between AWC (R2 = 0.7) and disturbance, with highest disturbed area (65 %) for AWC between 90 and 160 mm. Interestingly, we found no evidence for generally higher disturbance on shallow soils, although stands on the deepest soils were significantly less affected. Noteworthy, sites affected first did not necessarily exhibit highest proportions of disturbed area post-drought, indicating recovery or adaptation. We conclude that site- and species-specific understanding of drought impacts benefits from a combination of remote sensing and fine-scale soil information. Since our approach revealed which sites were affected first and most, it qualifies for prioritizing in situ monitoring activities to most vulnerable stands in acute drought conditions as well as for developing long-term strategies for reforestation and site-specific risk assessment for precision forestry.
Collapse
Affiliation(s)
- Birgitta Putzenlechner
- Institute of Geography, Dep. Cartography, GIS and Remote Sensing, Georg-August-University, Goldschmidtstr. 5, 37077 Göttingen, Germany.
| | - Philipp Koal
- Forestry Research and Competence Centre, ThüringenForst AöR, Jägerstr. 1, 99867 Gotha, Germany
| | - Martin Kappas
- Institute of Geography, Dep. Cartography, GIS and Remote Sensing, Georg-August-University, Goldschmidtstr. 5, 37077 Göttingen, Germany
| | - Markus Löw
- Federal Research and Training Centre for Forests Natural Hazards and Landscape, Seckendorff-Gudent-Weg 8, 1130 Vienna, Austria
| | - Philip Mundhenk
- Forestry Research and Competence Centre, ThüringenForst AöR, Jägerstr. 1, 99867 Gotha, Germany
| | - Alexander Tischer
- Institute of Geography, Friedrich-Schiller-University, Löbdergraben 32, 07743 Jena, Germany
| | - Jakob Wernicke
- Forestry Research and Competence Centre, ThüringenForst AöR, Jägerstr. 1, 99867 Gotha, Germany
| | - Tatjana Koukal
- Federal Research and Training Centre for Forests Natural Hazards and Landscape, Seckendorff-Gudent-Weg 8, 1130 Vienna, Austria
| |
Collapse
|
5
|
Tischer A, Moon-Tasson L, Auton M. Removal of the vicinal disulfide enhances the platelet-capturing function of von Willebrand factor. Blood 2023; 141:1469-1473. [PMID: 36603190 PMCID: PMC10082372 DOI: 10.1182/blood.2022018803] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/15/2022] [Accepted: 12/20/2022] [Indexed: 01/07/2023] Open
Abstract
A redox autoinhibitory mechanism has previously been proposed, in which the reduced state of the vicinal disulfide bond in the von Willebrand factor (VWF) A2 domain allows A2 to bind to A1 and inhibit platelet adhesion to the A1 domain. The VWF A1A2A3 tridomain was expressed with and without the vicinal disulfide in A2 (C1669S/C1670S) via the atomic replacement of sulfur for oxygen to test the relevance of the vicinal disulfide to the physiological platelet function of VWF under shear flow. A comparative study of the shear-dependent platelet translocation dynamics on these tridomain variants reveals that the reduction of the vicinal disulfide moderately increases the platelet-capturing function of A1, an observation counter to the proposed hypothesis. Surface plasmon resonance spectroscopy confirms that C1669S/C1670S slightly increases the affinity of A1A2A3 binding to glycoprotein Ibα (GPIbα). Differential scanning calorimetry and hydrogen-deuterium exchange mass spectrometry demonstrate that reduction of the vicinal disulfide destabilizes the A2 domain, which consequently disrupts interactions between the A1, A2, and A3 domains and enhances the conformational dynamics of A1-domain secondary structures known to regulate the strength of platelet adhesion to VWF. This study clarifies that the reduced state of the A2 vicinal disulfide is not inhibitory but rather slightly activating.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Laurie Moon-Tasson
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| |
Collapse
|
6
|
Meyer UN, Tischer A, Freitag M, Klaus VH, Kleinebecker T, Oelmann Y, Kandeler E, Hölzel N, Hamer U. Enzyme kinetics inform about mechanistic changes in tea litter decomposition across gradients in land-use intensity in Central German grasslands. Sci Total Environ 2022; 836:155748. [PMID: 35526633 DOI: 10.1016/j.scitotenv.2022.155748] [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] [Received: 10/03/2021] [Revised: 05/02/2022] [Accepted: 05/02/2022] [Indexed: 06/14/2023]
Abstract
Grassland ecosystems provide important ecosystem services such as nutrient cycling and primary production that are affected by land-use intensity. To assess the effects of land-use intensity, operational and sensitive ecological indicators that integrate effects of grassland management on ecosystem processes such as organic matter turnover are needed. Here, we investigated the suitability of measuring the mass loss of standardized tea litter together with extracellular enzyme kinetics as a proxy of litter decomposition in the topsoil of grasslands along a well-defined land-use intensity gradient (fertilization, mowing, grazing) in Central Germany. Tea bags containing either green tea (high-quality litter) or rooibos tea (low-quality litter) were buried in 5 cm soil depth. Litter mass loss was measured after three (early-stage decomposition) and 12 months (mid-stage decomposition). Based on the fluorescence measurement of the reaction product 4-methylumbelliferone, Michaelis-Menten enzyme kinetics (Vmax: potential maximum rate of activity; Km: substrate affinity) of five hydrolases involved in the carbon (C)-, nitrogen (N)- and phosphorus (P)-cycle (β-glucosidase (BG), cellobiohydrolase (CBH), cellotriohydrolase (CTH), 1,4-β-N-acetylglucosaminidase (NAG), and phosphatase (PH)) were determined in tea litter bags and in the surrounding soil. The land-use intensity index (LUI), summarizing fertilization, mowing, grazing, and in particular the frequency of mowing were identified as important drivers of early-stage tea litter decomposition. Mid-stage decomposition was influenced by grazing intensity. The higher the potential activity of all measured C-, N- and P-targeting enzymes, the higher was the decomposition of both tea litters in the early-phase. During mid-stage decomposition, individual enzyme parameters (Vmax of CTH and PH, Km of CBH) became more important. The tea bag method proved to be a suitable indicator which allows an easy and cost-effective assessment of land-use intensity effects on decay processes in manged grasslands. In combination with enzyme kinetics it is an appealing approach to identify mechanisms driving litter break down.
Collapse
Affiliation(s)
- Ulf-Niklas Meyer
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany
| | - Alexander Tischer
- Department of Soil Science, Friedrich-Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
| | - Martin Freitag
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany
| | - Valentin H Klaus
- Insitute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Universitätstrasse 2, 8092 Zürich, Switzerland
| | - Till Kleinebecker
- Institute for Landscape Ecology and Resource Management, Giessen University, Heinrich-Buff-Ring 26-32, 35392 Gießen, Germany
| | - Yvonne Oelmann
- Geoecology, Department of Geosciences, University of Tübingen, Rümelinstr. 19-23, 72070 Tübingen, Germany
| | - Ellen Kandeler
- Institute of Soil Science and Land Evaluation, Department of Soil Biology, University of Hohenheim, Emil Wolff Str. 27, 70599 Stuttgart, Germany
| | - Norbert Hölzel
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany
| | - Ute Hamer
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany.
| |
Collapse
|
7
|
MacArthur TA, Goswami J, Moon Tasson L, Tischer A, Bailey KR, Spears GM, Dong JF, Auton M, Kozar R, Park MS. Quantification of von Willebrand factor and ADAMTS-13 after traumatic injury: a pilot study. Trauma Surg Acute Care Open 2021; 6:e000703. [PMID: 33912688 PMCID: PMC8030476 DOI: 10.1136/tsaco-2021-000703] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Von Willebrand factor (VWF) is an acute phase reactant synthesized in the megakaryocytes and endothelial cells. VWF forms ultra-large multimers (ULVWF) which are cleaved by the metalloprotease ADAMTS-13, preventing spontaneous VWF-platelet interaction. After trauma, ULVWF is released into circulation as part of the acute phase reaction. We hypothesized that trauma patients would have increased levels of VWF and decreased levels of ADAMTS-13 and that these patients would have accelerated thrombin generation. METHODS We assessed plasma concentrations of VWF antigen and ADAMTS-13 antigen, the Rapid Enzyme Assays for Autoimmune Diseases (REAADS) activity of VWF, which measure exposure of the platelet-binding A1 domain, and thrombin generation kinetics in 50 samples from 30 trauma patients and an additional 21 samples from volunteers. Samples were analyzed at 0 to 2 hours and at 6 hours from the time of injury. Data are presented as median (IQR) and Kruskal-Wallis test was performed between trauma patients and volunteers at both time points. RESULTS REAADS activity was greater in trauma patients than volunteers both at 0 to 2 hours (190.0 (132.0-264.0) vs. 92.0 (71.0-114.0), p<0.002) and at 6 hours (167.5 (108.0-312.5.0) vs. 92.0 (71.0-114.0), p<0.001). ADAMTS-13 antigen levels were also decreased in trauma patients both at 0 to 2 hours (0.84 (0.51-0.94) vs. 1.00 (0.89-1.09), p=0.010) and at 6 hours (0.653 (0.531-0.821) vs. 1.00 (0.89-1.09), p<0.001). Trauma patients had accelerated thrombin generation kinetics, with greater peak height and shorter time to peak than healthy volunteers at both time points. DISCUSSION Trauma patients have increased exposure of the VWF A1 domain and decreased levels of ADAMTS-13 compared with healthy volunteers. This suggests that the VWF burst after trauma may exceed the proteolytic capacity of ADAMTS-13, allowing circulating ULVWF multimers to bind platelets, potentially contributing to trauma-induced coagulopathy. LEVEL OF EVIDENCE Prospective case cohort study.
Collapse
Affiliation(s)
- Taleen A MacArthur
- Trauma, Critical Care and General Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Julie Goswami
- Trauma, Critical Care and General Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | - Kent R Bailey
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, USA
| | - Grant M Spears
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, USA
| | - Jing-Fei Dong
- Department of Hematology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Matthew Auton
- Biochemistry and Molecular Biology, Mayo Clinic, Rochester, New York, USA
| | - Rosemary Kozar
- Department of Surgery, R Adams Cowley Shock Trauma Center, Baltimore, Maryland, USA
| | | |
Collapse
|
8
|
Potthast K, Meyer S, Tischer A, Gleixner G, Sieburg A, Frosch T, Michalzik B. Grasshopper herbivory immediately affects element cycling but not export rates in an N‐limited grassland system. Ecosphere 2021. [DOI: 10.1002/ecs2.3449] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Karin Potthast
- Institute of Geography/Chair of Soil Science Friedrich Schiller University Jena Löbdergraben 32 Jena07743Germany
| | - Stefanie Meyer
- Medical Center LMU Munich Ziemssenstraße 1 Munchen80336Germany
| | - Alexander Tischer
- Institute of Geography/Chair of Soil Science Friedrich Schiller University Jena Löbdergraben 32 Jena07743Germany
| | - Gerd Gleixner
- Research Group of Molecular Biogeochemistry MPI for Biogeochemistry Hans‐Knöll‐Straße 10 Jena07745Germany
| | - Anne Sieburg
- Leibniz Institute of Photonic Technology Jena07745Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology Jena07745Germany
- Institute of Physical Chemistry and Abbe Centre of Photonics Friedrich Schiller University Jena Jena07745Germany
| | - Beate Michalzik
- Institute of Geography/Chair of Soil Science Friedrich Schiller University Jena Löbdergraben 32 Jena07743Germany
- German Center for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
| |
Collapse
|
9
|
Muñoz-Alía MÁ, Nace RA, Tischer A, Zhang L, Bah ES, Auton M, Russell SJ. MeV-Stealth: A CD46-specific oncolytic measles virus resistant to neutralization by measles-immune human serum. PLoS Pathog 2021; 17:e1009283. [PMID: 33534834 PMCID: PMC7886131 DOI: 10.1371/journal.ppat.1009283] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 02/16/2021] [Accepted: 01/05/2021] [Indexed: 02/07/2023] Open
Abstract
The frequent overexpression of CD46 in malignant tumors has provided a basis to use vaccine-lineage measles virus (MeV) as an oncolytic virotherapy platform. However, widespread measles seropositivity limits the systemic deployment of oncolytic MeV for the treatment of metastatic neoplasia. Here, we report the development of MeV-Stealth, a modified vaccine MeV strain that exhibits oncolytic properties and escapes antimeasles antibodies in vivo. We engineered this virus using homologous envelope glycoproteins from the closely-related but serologically non-cross reactive canine distemper virus (CDV). By fusing a high-affinity CD46 specific single-chain antibody fragment (scFv) to the CDV-Hemagglutinin (H), ablating its tropism for human nectin-4 and modifying the CDV-Fusion (F) signal peptide we achieved efficient retargeting to CD46. A receptor binding affinity of ~20 nM was required to trigger CD46-dependent intercellular fusion at levels comparable to the original MeV H/F complex and to achieve similar antitumor efficacy in myeloma and ovarian tumor-bearing mice models. In mice passively immunized with measles-immune serum, treatment of ovarian tumors with MeV-Stealth significantly increased overall survival compared with treatment with vaccine-lineage MeV. Our results show that MeV-Stealth effectively targets and lyses CD46-expressing cancer cells in mouse models of ovarian cancer and myeloma, and evades inhibition by human measles-immune serum. MeV-Stealth could therefore represent a strong alternative to current oncolytic MeV strains for treatment of measles-immune cancer patients. Vaccine strains of the measles virus (MeV) have been shown to be promising anti-cancer agents because of the frequent overexpression of the host-cell receptor CD46 in human malignancies. However, anti-MeV antibodies in the human population severely restrict the use of MeV as an oncolytic agent. Here, we engineered a neutralization-resistant MeV vaccine, MeV-Stealth, by replacing its envelope glycoproteins with receptor-targeted glycoproteins from wild-type canine distemper virus. By fully-retargeting the new envelope to the receptor CD46, we found that in mouse models of ovarian cancer and myeloma MeV-Stealth displayed oncolytic properties similar to the parental MeV vaccine. Furthermore, we found that passive immunization with measles-immune human serum did not eliminate the oncolytic potency of the MeV-Stealth, whereas it did destroy the potency of the parental MeV strain. The virus we here report may be considered a suitable oncolytic agent for the treatment of MeV-immune patients.
Collapse
Affiliation(s)
- Miguel Ángel Muñoz-Alía
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (MÁM-A); (SJR)
| | - Rebecca A. Nace
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Alexander Tischer
- Division of Hematology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Lianwen Zhang
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Eugene S. Bah
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, United States of America
| | - Matthew Auton
- Division of Hematology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Stephen J. Russell
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Division of Hematology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (MÁM-A); (SJR)
| |
Collapse
|
10
|
Huck V, Chen PC, Xu ER, Tischer A, Klemm U, Aponte-Santamaría C, Mess C, Obser T, Kutzki F, König G, Denis CV, Gräter F, Wilmanns M, Auton M, Schneider SW, Schneppenheim R, Hennig J, Brehm MA. Gain-of-Function Variant p.Pro2555Arg of von Willebrand Factor Increases Aggregate Size through Altering Stem Dynamics. Thromb Haemost 2020; 122:226-239. [PMID: 33385180 PMCID: PMC8828397 DOI: 10.1055/a-1344-4405] [Citation(s) in RCA: 0] [Impact Index Per Article: 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] [Indexed: 11/02/2022]
Abstract
The multimeric plasma glycoprotein (GP) von Willebrand factor (VWF) is best known for recruiting platelets to sites of injury during primary hemostasis. Generally, mutations in the VWF gene lead to loss of hemostatic activity and thus the bleeding disorder von Willebrand disease. By employing cone and platelet aggregometry and microfluidic assays, we uncovered a platelet GPIIb/IIIa-dependent prothrombotic gain of function (GOF) for variant p.Pro2555Arg, located in the C4 domain, leading to an increase in platelet aggregate size. We performed complementary biophysical and structural investigations using circular dichroism spectra, small-angle X-ray scattering, nuclear magnetic resonance spectroscopy, molecular dynamics simulations on the single C4 domain, and dimeric wild-type and p.Pro2555Arg constructs. C4-p.Pro2555Arg retained the overall structural conformation with minor populations of alternative conformations exhibiting increased hinge flexibility and slow conformational exchange. The dimeric protein becomes disordered and more flexible. Our data suggest that the GOF does not affect the binding affinity of the C4 domain for GPIIb/IIIa. Instead, the increased VWF dimer flexibility enhances temporal accessibility of platelet-binding sites. Using an interdisciplinary approach, we revealed that p.Pro2555Arg is the first VWF variant, which increases platelet aggregate size and shows a shear-dependent function of the VWF stem region, which can become hyperactive through mutations. Prothrombotic GOF variants of VWF are a novel concept of a VWF-associated pathomechanism of thromboembolic events, which is of general interest to vascular health but not yet considered in diagnostics. Thus, awareness should be raised for the risk they pose. Furthermore, our data implicate the C4 domain as a novel antithrombotic drug target.
Collapse
Affiliation(s)
- Volker Huck
- Department of Dermatology and Venereology, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Experimental Dermatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Po-Chia Chen
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Emma-Ruoqi Xu
- European Molecular Biology Laboratory, Hamburg Unit, Hamburg, Germany
| | - Alexander Tischer
- Division of Hematology, Mayo Clinic, Rochester, Minnesota, United States
| | - Ulrike Klemm
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Camilo Aponte-Santamaría
- Max Planck Tandem Group in Computational Biophysics, University of los Andes, Bogotá, Colombia.,Interdisciplinary Center for Scientific Computing, Heidelberg University, Heidelberg, Germany
| | - Christian Mess
- Department of Dermatology and Venereology, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tobias Obser
- Department of Dermatology and Venereology, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fabian Kutzki
- Molecular Biomechanics Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany.,Institute of Physical Chemistry, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Gesa König
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Cécile V Denis
- Laboratory of Hemostasis, Inflammation and Thrombosis, Institut National de la Santé et de la Recherche Médicale UMR_1176, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Frauke Gräter
- Interdisciplinary Center for Scientific Computing, Heidelberg University, Heidelberg, Germany.,Molecular Biomechanics Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany
| | - Matthias Wilmanns
- European Molecular Biology Laboratory, Hamburg Unit, Hamburg, Germany.,University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Matthew Auton
- Division of Hematology, Mayo Clinic, Rochester, Minnesota, United States
| | - Stefan W Schneider
- Department of Dermatology and Venereology, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Reinhard Schneppenheim
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Janosch Hennig
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Maria A Brehm
- Department of Dermatology and Venereology, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
11
|
Knoke T, Paul C, Rammig A, Gosling E, Hildebrandt P, Härtl F, Peters T, Richter M, Diertl KH, Castro LM, Calvas B, Ochoa S, Valle-Carrión LA, Hamer U, Tischer A, Potthast K, Windhorst D, Homeier J, Wilcke W, Velescu A, Gerique A, Pohle P, Adams J, Breuer L, Mosandl R, Beck E, Weber M, Stimm B, Silva B, Verburg PH, Bendix J. Accounting for multiple ecosystem services in a simulation of land-use decisions: Does it reduce tropical deforestation? Glob Chang Biol 2020; 26:2403-2420. [PMID: 31957121 DOI: 10.1111/gcb.15003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 12/25/2019] [Accepted: 01/12/2020] [Indexed: 06/10/2023]
Abstract
Conversion of tropical forests is among the primary causes of global environmental change. The loss of their important environmental services has prompted calls to integrate ecosystem services (ES) in addition to socio-economic objectives in decision-making. To test the effect of accounting for both ES and socio-economic objectives in land-use decisions, we develop a new dynamic approach to model deforestation scenarios for tropical mountain forests. We integrate multi-objective optimization of land allocation with an innovative approach to consider uncertainty spaces for each objective. These uncertainty spaces account for potential variability among decision-makers, who may have different expectations about the future. When optimizing only socio-economic objectives, the model continues the past trend in deforestation (1975-2015) in the projected land-use allocation (2015-2070). Based on indicators for biomass production, carbon storage, climate and water regulation, and soil quality, we show that considering multiple ES in addition to the socio-economic objectives has heterogeneous effects on land-use allocation. It saves some natural forest if the natural forest share is below 38%, and can stop deforestation once the natural forest share drops below 10%. For landscapes with high shares of forest (38%-80% in our study), accounting for multiple ES under high uncertainty of their indicators may, however, accelerate deforestation. For such multifunctional landscapes, two main effects prevail: (a) accelerated expansion of diversified non-natural areas to elevate the levels of the indicators and (b) increased landscape diversification to maintain multiple ES, reducing the proportion of natural forest. Only when accounting for vascular plant species richness as an explicit objective in the optimization, deforestation was consistently reduced. Aiming for multifunctional landscapes may therefore conflict with the aim of reducing deforestation, which we can quantify here for the first time. Our findings are relevant for identifying types of landscapes where this conflict may arise and to better align respective policies.
Collapse
Affiliation(s)
- Thomas Knoke
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Carola Paul
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Department of Forest Economics and Sustainable Land-use Planning, Georg-August University Goettingen, Goettingen, Germany
| | - Anja Rammig
- Professorship for Land Surface-Atmosphere Interactions, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Elizabeth Gosling
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Patrick Hildebrandt
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Institute of Silviculture, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Fabian Härtl
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Thorsten Peters
- Institute of Geography, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Richter
- Institute of Geography, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Karl-Heinz Diertl
- Institute of Geography, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Luz Maria Castro
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Department of Economics, Universidad Técnica Particular de Loja, Loja, Ecuador
| | - Baltazar Calvas
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Department of Economics, Universidad Técnica Particular de Loja, Loja, Ecuador
- Facultad de Ciencias Pecuarias, Universidad Técnica Estatal de Quevedo, Quevedo, Ecuador
| | - Santiago Ochoa
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Department of Economics, Universidad Técnica Particular de Loja, Loja, Ecuador
| | - Liz Anabelle Valle-Carrión
- Institute of Forest Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Department of Economics, Universidad Técnica Particular de Loja, Loja, Ecuador
| | - Ute Hamer
- Institute of Landscape Ecology, University of Muenster, Münster, Germany
| | - Alexander Tischer
- Institute of Geography, Friedrich-Schiller-University Jena, Jena, Germany
| | - Karin Potthast
- Institute of Geography, Friedrich-Schiller-University Jena, Jena, Germany
| | - David Windhorst
- Institute for Landscape Ecology and Resources Management, Justus Liebig University Giessen, Giessen, Germany
| | - Jürgen Homeier
- Plant Ecology and Ecosystems Research, University of Goettingen, Goettingen, Germany
| | - Wolfgang Wilcke
- Institute of Geography and Geoecology, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Andre Velescu
- Institute of Geography and Geoecology, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Andres Gerique
- Institute of Geography, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Perdita Pohle
- Institute of Geography, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Julia Adams
- Department of Plant Physiology and Bayreuth Centre of Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany
| | - Lutz Breuer
- Institute for Landscape Ecology and Resources Management, Justus Liebig University Giessen, Giessen, Germany
- Centre for International Development and Environmental Research (ZEU), Justus Liebig University Giessen, Giessen, Germany
| | - Reinhard Mosandl
- Institute of Silviculture, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Erwin Beck
- Department of Plant Physiology and Bayreuth Centre of Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany
| | - Michael Weber
- Institute of Silviculture, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Bernd Stimm
- Institute of Silviculture, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Brenner Silva
- Laboratory for Climatology and Remote Sensing (LCRS), Faculty of Geography, University of Marburg, Marburg, Germany
| | - Peter H Verburg
- Department of Environmental Geography, Institute for Environmental Studies, VU University Amsterdam, Amsterdam, The Netherlands
| | - Jörg Bendix
- Laboratory for Climatology and Remote Sensing (LCRS), Faculty of Geography, University of Marburg, Marburg, Germany
| |
Collapse
|
12
|
Gao YG, My Le LT, Zhai X, Boldyrev IA, Mishra SK, Tischer A, Murayama T, Nishida A, Molotkovsky JG, Alam A, Brown RE. Measuring Lipid Transfer Protein Activity Using Bicelle-Dilution Model Membranes. Anal Chem 2020; 92:3417-3425. [PMID: 31970977 DOI: 10.1021/acs.analchem.9b05523] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In vitro assessment of lipid intermembrane transfer activity by cellular proteins typically involves measurement of either radiolabeled or fluorescently labeled lipid trafficking between vesicle model membranes. Use of bilayer vesicles in lipid transfer assays usually comes with inherent challenges because of complexities associated with the preparation of vesicles and their rather short "shelf life". Such issues necessitate the laborious task of fresh vesicle preparation to achieve lipid transfer assays of high quality, precision, and reproducibility. To overcome these limitations, we have assessed model membrane generation by bicelle dilution for monitoring the transfer rates and specificity of various BODIPY-labeled sphingolipids by different glycolipid transfer protein (GLTP) superfamily members using a sensitive fluorescence resonance energy transfer approach. Robust, protein-selective sphingolipid transfer is observed using donor and acceptor model membranes generated by dilution of 0.5 q-value mixtures. The sphingolipid transfer rates are comparable to those observed between small bilayer vesicles produced by sonication or ethanol injection. Among the notable advantages of using bicelle-generated model membranes are (i) easy and straightforward preparation by means that avoid lipid fluorophore degradation and (ii) long "shelf life" after production (≥6 days) and resilience to freeze-thaw storage. The bicelle-dilution-based assay is sufficiently robust, sensitive, and stable for application, not only to purified LTPs but also for LTP activity detection in crude cytosolic fractions of cell homogenates.
Collapse
Affiliation(s)
- Yong-Guang Gao
- The Hormel Institute , University of Minnesota , 801 16th Avenue NE , Austin , Minnesota 55912 , United States
| | - Le Thi My Le
- The Hormel Institute , University of Minnesota , 801 16th Avenue NE , Austin , Minnesota 55912 , United States
| | - Xiuhong Zhai
- The Hormel Institute , University of Minnesota , 801 16th Avenue NE , Austin , Minnesota 55912 , United States
| | - Ivan A Boldyrev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry , Russian Academy of Sciences , 117997 Moscow , Russian Federation
| | - Shrawan K Mishra
- The Hormel Institute , University of Minnesota , 801 16th Avenue NE , Austin , Minnesota 55912 , United States
| | - Alexander Tischer
- Mayo Clinic Division of Hematology , 150 Third Street SW , Stabile Building, Rochester , Minnesota 55905 , United States
| | - Toshihiko Murayama
- Graduate School of Pharmaceutical Sciences , Chiba University , Inohana 1-8-1 , Chuo-ku, Chiba 260-8675 , Japan
| | - Atsushi Nishida
- Graduate School of Pharmaceutical Sciences , Chiba University , Inohana 1-8-1 , Chuo-ku, Chiba 260-8675 , Japan
| | - Julian G Molotkovsky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry , Russian Academy of Sciences , 117997 Moscow , Russian Federation
| | - Amer Alam
- The Hormel Institute , University of Minnesota , 801 16th Avenue NE , Austin , Minnesota 55912 , United States
| | - Rhoderick E Brown
- The Hormel Institute , University of Minnesota , 801 16th Avenue NE , Austin , Minnesota 55912 , United States
| |
Collapse
|
13
|
Tischer A, Machha VR, Moon-Tasson L, Benson LM, Auton M. Glycosylation sterically inhibits platelet adhesion to von Willebrand factor without altering intrinsic conformational dynamics. J Thromb Haemost 2020; 18:79-90. [PMID: 31479573 PMCID: PMC6940534 DOI: 10.1111/jth.14628] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/26/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND A molecular basis for von Willebrand factor (VWF) self-inhibition has been proposed by which the N-terminal and C-terminal flanking sequences of the globular A1 domain disulfide loop bind to and suppress the conformational dynamics of A1. These flanking sequences are rich in O-linked glycosylation (OLG), which is known to suppress platelet adhesion to VWF, presumably by steric hindrance. The inhibitory mechanism remains unresolved as to whether inhibition is due to steric exclusion by OLGs or a direct self-association interaction that stabilizes the domain. OBJECTIVES The platelet adhesive function, thermodynamic stability, and conformational dynamics of the wild-type and type 2M G1324S A1 domain lacking glycosylation (Escherichia coli) are compared with the wild-type glycosylated A1 domain (HEK293 cell culture) to decipher the self-inhibitory mechanism. METHODS Surface plasmon resonance and analytical rheology are utilized to assess Glycoprotein Ibα (GPIbα) binding at equilibrium and platelet adhesion under shear flow. The conformational stability is assessed through a combination of protein unfolding thermodynamics and hydrogen-deuterium exchange mass spectrometry (HXMS). RESULTS A1 glycosylation inhibits both GPIbα binding and platelet adhesion. Glycosylation increases the hydrodynamic size of A1 and stabilizes the thermal unfolding of A1 without changing its equilibrium stability. Glycosylation does not alter the intrinsic conformational dynamics of the A1 domain. CONCLUSIONS These studies invalidate the proposed inhibition through conformational suppression since glycosylation within these flanking sequences does not alter the native state stability or the conformational dynamics of A1. Rather, they confirm a mechanism by which glycosylation sterically hinders platelet adhesion to the A1 domain at equilibrium and under rheological shear stress.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, 55905, USA
| | - Venkata R. Machha
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, 55905, USA
| | - Laurie Moon-Tasson
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, 55905, USA
| | - Linda M. Benson
- Proteomics Core, Department of Biochemistry and Molecular Biology, College of Medicine, Mayo Clinic, Rochester, Minnesota, 55905, USA
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, 55905, USA
| |
Collapse
|
14
|
Tischer A, Machha VR, Moon-Tasson L, Auton M. Platelet-type von Willebrand disease: Local disorder of the platelet GPIbα β-switch drives high-affinity binding to von Willebrand factor. J Thromb Haemost 2019; 17:2022-2034. [PMID: 31448872 DOI: 10.1111/jth.14597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 02/22/2019] [Accepted: 07/26/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Mutations in the β-switch of GPIbα cause gain-of-function in the platelet-type von Willebrand disease. Structures of free and A1-bound GPIbα suggest that the β-switch undergoes a conformational change from a coil to a β-hairpin. OBJECTIVES Platelet-type von Willebrand disease (VWD) mutations have been proposed to stabilize the β-switch by shifting the equilibrium in favor of the β-hairpin, a hypothesis predicated on the assumption that the complex crystal structure between A1 and GPIbα is the high-affinity state. METHODS Hydrogen-deuterium exchange mass spectrometry is employed to test this hypothesis using G233V, M239V, G233V/M239V, W230L, and D235Y disease variants of GPIbα. If true, the expectation is a decrease in hydrogen-deuterium exchange within the β-switch as a result of newly formed hydrogen bonds between the β-strands of the β-hairpin. RESULTS Hydrogen-exchange is enhanced, indicating that the β-switch favors the disordered loop conformation. Hydrogen-exchange is corroborated by differential scanning calorimetry, which confirms that these mutations destabilize GPIbα by allowing the β-switch to dissociate from the leucine-rich-repeat (LRR) domain. The stability of GPIbα and its A1 binding affinity, determined by surface plasmon resonance, are correlated to the extent of hydrogen exchange in the β-switch. CONCLUSION These studies demonstrate that GPIbα with a disordered loop is binding-competent and support a mechanism in which local disorder in the β-switch exposes the LRR-domain of GPIbα enabling high-affinity interactions with the A1 domain.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Venkata R Machha
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Laurie Moon-Tasson
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
15
|
Tischer A, Antelo G, Coltro G, Finke CM, Gonsalves W, Pardanani A, Ketterling R, Mangaonkar A, Gangat N, Tefferi A, Patnaik MM, Lasho TL. Functional evaluation of isocitrate dehydrogenase 1 and 2 variants of unclear significance in chronic myeloid neoplasms. Leuk Res 2019; 87:106264. [PMID: 31706195 DOI: 10.1016/j.leukres.2019.106264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 10/21/2019] [Indexed: 11/19/2022]
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Guadalupe Antelo
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Giacomo Coltro
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Christy M Finke
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Wilson Gonsalves
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Animesh Pardanani
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Rhett Ketterling
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Abhishek Mangaonkar
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Naseema Gangat
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Ayalew Tefferi
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Mrinal M Patnaik
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Terra L Lasho
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA.
| |
Collapse
|
16
|
Tischer A, Brown MJ, Schleif RF, Auton M. Arabinose Alters Both Local and Distal H-D Exchange Rates in the Escherichia coli AraC Transcriptional Regulator. Biochemistry 2019; 58:2875-2882. [PMID: 31199144 DOI: 10.1021/acs.biochem.9b00389] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In the absence of arabinose, the dimeric Escherichia coli regulatory protein of the l-arabinose operon, AraC, represses expression by looping the DNA between distant half-sites. Binding of arabinose to the dimerization domains forces AraC to preferentially bind two adjacent DNA half-sites, which stimulates RNA polymerase transcription of the araBAD catabolism genes. Prior genetic and biochemical studies hypothesized that arabinose allosterically induces a helix-coil transition of a linker between the dimerization and DNA binding domains that switches the AraC conformation to an inducing state [Brown, M. J., and Schleif, R. F. (2019) Biochemistry, preceding paper in this issue (DOI: 10.1021/acs.biochem.9b00234)]. To test this hypothesis, hydrogen-deuterium exchange mass spectrometry was utilized to identify structural regions involved in the conformational activation of AraC by arabinose. Comparison of the hydrogen-deuterium exchange kinetics of individual dimeric dimerization domains and the full-length dimeric AraC protein in the presence and absence of arabinose reveals a prominent arabinose-induced destabilization of the amide hydrogen-bonded structure of linker residues (I167 and N168). This destabilization is demonstrated to result from an increased probability to form a helix capping motif at the C-terminal end of the dimerizing α-helix of the dimerization domain that preceeds the interdomain linker. These conformational changes could allow for quaternary repositioning of the DNA binding domains required for induction of the araBAD promoter through rotation of peptide backbone dihedral angles of just a couple of residues. Subtle changes in exchange rates are also visible around the arabinose binding pocket and in the DNA binding domain.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology , Mayo Clinic , Rochester , Minnesota 55905 , United States
| | - Matthew J Brown
- Department of Biology , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Robert F Schleif
- Department of Biology , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology , Mayo Clinic , Rochester , Minnesota 55905 , United States
| |
Collapse
|
17
|
Shenoy N, Bhagat TD, Cheville J, Lohse C, Bhattacharyya S, Tischer A, Machha V, Gordon-Mitchell S, Choudhary G, Wong LF, Gross L, Ressigue E, Leibovich B, Boorjian SA, Steidl U, Wu X, Pradhan K, Gartrell B, Agarwal B, Pagliaro L, Suzuki M, Greally JM, Rakheja D, Thompson RH, Susztak K, Witzig T, Zou Y, Verma A. Ascorbic acid-induced TET activation mitigates adverse hydroxymethylcytosine loss in renal cell carcinoma. J Clin Invest 2019; 129:1612-1625. [PMID: 30702441 DOI: 10.1172/jci98747] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [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: 11/30/2017] [Accepted: 01/24/2019] [Indexed: 12/31/2022] Open
Abstract
Although clear cell renal cell carcinoma (ccRCC) has been shown to result in widespread aberrant cytosine methylation and loss of 5-hydroxymethylcytosine (5hmC), the prognostic impact and therapeutic targeting of this epigenetic aberrancy has not been fully explored. Analysis of 576 primary ccRCC samples demonstrated that loss of 5hmC was strongly associated with aggressive clinicopathologic features and was an independent adverse prognostic factor. Loss of 5hmC also predicted reduced progression-free survival after resection of nonmetastatic disease. The loss of 5hmC in ccRCC was not due to mutational or transcriptional inactivation of ten eleven translocation (TET) enzymes, but to their functional inactivation by l-2-hydroxyglutarate (L2HG), which was overexpressed due to the deletion and underexpression of L2HG dehydrogenase (L2HGDH). Ascorbic acid (AA) reduced methylation and restored genome-wide 5hmC levels via TET activation. Fluorescence quenching of the recombinant TET-2 protein was unaffected by L2HG in the presence of AA. Pharmacologic AA treatment led to reduced growth of ccRCC in vitro and reduced tumor growth in vivo, with increased intratumoral 5hmC. These data demonstrate that reduced 5hmC is associated with reduced survival in ccRCC and provide a preclinical rationale for exploring the therapeutic potential of high-dose AA in ccRCC.
Collapse
Affiliation(s)
- Niraj Shenoy
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | - Tushar D Bhagat
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | | | | | | | | | | | | | - Gaurav Choudhary
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | - Li-Fan Wong
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | | | - Emily Ressigue
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | | | | | - Ulrich Steidl
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | | | - Kith Pradhan
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | - Benjamin Gartrell
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | | | | | - Masako Suzuki
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | - John M Greally
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | - Dinesh Rakheja
- University of Texas Southwestern Medical School, Dallas, Texas, USA
| | | | - Katalin Susztak
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | | | - Yiyu Zou
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| | - Amit Verma
- Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York, USA
| |
Collapse
|
18
|
O'Neil PT, Machen AJ, Deatherage BC, Trecazzi C, Tischer A, Machha VR, Auton MT, Baldwin MR, White TA, Fisher MT. The Chaperonin GroEL: A Versatile Tool for Applied Biotechnology Platforms. Front Mol Biosci 2018; 5:46. [PMID: 29868607 PMCID: PMC5962814 DOI: 10.3389/fmolb.2018.00046] [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: 02/15/2018] [Accepted: 04/23/2018] [Indexed: 01/06/2023] Open
Abstract
The nucleotide-free chaperonin GroEL is capable of capturing transient unfolded or partially unfolded states that flicker in and out of existence due to large-scale protein dynamic vibrational modes. In this work, three short vignettes are presented to highlight our continuing advances in the application of GroEL biosensor biolayer interferometry (BLI) technologies and includes expanded uses of GroEL as a molecular scaffold for electron microscopy determination. The first example presents an extension of the ability to detect dynamic pre-aggregate transients in therapeutic protein solutions where the assessment of the kinetic stability of any folded protein or, as shown herein, quantitative detection of mutant-type protein when mixed with wild-type native counterparts. Secondly, using a BLI denaturation pulse assay with GroEL, the comparison of kinetically controlled denaturation isotherms of various von Willebrand factor (vWF) triple A domain mutant-types is shown. These mutant-types are single point mutations that locally disorder the A1 platelet binding domain resulting in one gain of function and one loss of function phenotype. Clear, separate, and reproducible kinetic deviations in the mutant-type isotherms exist when compared with the wild-type curve. Finally, expanding on previous electron microscopy (EM) advances using GroEL as both a protein scaffold surface and a release platform, examples are presented where GroEL-protein complexes can be imaged using electron microscopy tilt series and the low-resolution structures of aggregation-prone proteins that have interacted with GroEL. The ability of GroEL to bind hydrophobic regions and transient partially folded states allows one to employ this unique molecular chaperone both as a versatile structural scaffold and as a sensor of a protein's folded states.
Collapse
Affiliation(s)
- Pierce T O'Neil
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, United States
| | - Alexandra J Machen
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, United States
| | - Benjamin C Deatherage
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, United States
| | - Caleb Trecazzi
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, United States
| | - Alexander Tischer
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States
| | - Venkata R Machha
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States
| | - Matthew T Auton
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States
| | - Michael R Baldwin
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, United States
| | - Tommi A White
- Department of Biochemistry, University of Missouri, Columbia, MO, United States.,Electron Microscopy Core Facility, University of Missouri, Columbia, MO, United States
| | - Mark T Fisher
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, United States
| |
Collapse
|
19
|
Lasho TL, Finke CM, Tischer A, Pardanani A, Tefferi A. Mayo CALR mutation type classification guide using alpha helix propensity. Am J Hematol 2018; 93:E128-E129. [PMID: 29424450 DOI: 10.1002/ajh.25065] [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: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 01/23/2023]
Affiliation(s)
- Terra L. Lasho
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| | - Christy M. Finke
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| | - Alexander Tischer
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| | - Animesh Pardanani
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| |
Collapse
|
20
|
Tischer A, Machha VR, Rösgen J, Auton M. "Cooperative collapse" of the denatured state revealed through Clausius-Clapeyron analysis of protein denaturation phase diagrams. Biopolymers 2018; 109:e23106. [PMID: 29457634 DOI: 10.1002/bip.23106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 01/20/2018] [Accepted: 01/23/2018] [Indexed: 11/09/2022]
Abstract
Protein phase diagrams have a unique potential to identify the presence of additional thermodynamic states even when non-2-state character is not readily apparent from the experimental observables used to follow protein unfolding transitions. Two-state analysis of the von Willebrand factor A3 domain has previously revealed a discrepancy in the calorimetric enthalpy obtained from thermal unfolding transitions as compared with Gibbs-Helmholtz analysis of free energies obtained from the Linear Extrapolation Method (Tischer and Auton, Prot Sci 2013; 22(9):1147-60). We resolve this thermodynamic conundrum using a Clausius-Clapeyron analysis of the urea-temperature phase diagram that defines how Δ H and the urea m-value interconvert through the slope of cm versus T, ( ∂ c m / ∂ T ) = Δ H / ( m T ) . This relationship permits the calculation of Δ H at low temperature from m-values obtained through iso-thermal urea denaturation and high temperature m-values from Δ H obtained through iso-urea thermal denaturation. Application of this equation uncovers sigmoid transitions in both cooperativity parameters as temperature is increased. Such residual thermal cooperativity of Δ H and the m-value confirms the presence of an additional state which is verified to result from a cooperative phase transition between urea-expanded and thermally-compact denatured states. Comparison of the equilibria between expanded and compact denatured ensembles of disulfide-intact and carboxyamidated A3 domains reveals that introducing a single disulfide crosslink does not affect the presence of the additional denatured state. It does, however, make a small thermodynamically favorable free energy (∼-13 ± 1 kJ/mol) contribution to the cooperative denatured state collapse transition as temperature is raised and urea concentration is lowered. The thermodynamics of this "cooperative collapse" of the denatured state retain significant compensations between the enthalpy and entropy contributions to the overall free energy.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Venkata R Machha
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Jörg Rösgen
- Department Biochemistry and Molecular Biology, Penn State University College of Medicine, Hershey, Pennsylvania, 17033
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| |
Collapse
|
21
|
Potthast K, Meyer S, Crecelius AC, Schubert US, Tischer A, Michalzik B. Land-use and fire drive temporal patterns of soil solution chemistry and nutrient fluxes. Sci Total Environ 2017; 605-606:514-526. [PMID: 28672240 DOI: 10.1016/j.scitotenv.2017.06.182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 06/22/2017] [Accepted: 06/22/2017] [Indexed: 06/07/2023]
Abstract
Land-use type and ecosystem disturbances are important drivers for element cycling and bear the potential to modulate soil processes and hence ecosystem functions. To better understand the effect of such drivers on the magnitude and temporal patterns of organic matter (OM) and associated nutrient fluxes in soils, continuous flux monitoring is indispensable but insufficiently studied yet. We conducted a field study to elucidate the impact of land-use and surface fires on OM and nutrient fluxes with soil solution regarding seasonal and temporal patterns analyzing short (<3months) and medium-term (3-12months) effects. Control and prescribed fire-treated topsoil horizons in beech forests and pastures were monitored biweekly for dissolved and particulate OM (DOM, POM) and solution chemistry (pH value, elements: Ca, Mg, Na, K, Al, Fe, Mn, P, S, Si) over one post-fire year. Linear mixed model analyses exhibited that mean annual DOM and POM fluxes did not differ between the two land-use types, but were subjected to strong seasonal patterns. Fire disturbance significantly lowered the annual soil solution pH in both land-uses and increased water fluxes, while DOC fluxes remained unaffected. A positive response of POC and S to fire was limited to short-term effects, while amplified particulate and dissolved nitrogen fluxes were observed in the longer run and co-ocurred with accelerated Ca and Mg fluxes. In summary, surface fires generated stronger effects on element fluxes than the land-use. Fire-induced increases in POM fluxes suggest that the particulate fraction represent a major pathway of OM translocation into the subsoil and beyond. With regard to ecosystem functions, pasture ecosystems were less prone to the risk of nutrient losses following fire events than the forest. In pastures, fire-induced base cation export may accelerate soil acidification, consequently exhausting soil buffer systems and thus may reduce the resilience to acidic depositions and disturbances.
Collapse
Affiliation(s)
- Karin Potthast
- Department of Soil Science, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany.
| | - Stefanie Meyer
- Medical Center LMU Munich, Ziemssenstraße 1, 80336 München, Germany
| | - Anna C Crecelius
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstr. 10, 07743 Jena, Germany; Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Ulrich S Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstr. 10, 07743 Jena, Germany; Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany
| | - Alexander Tischer
- Department of Soil Science, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
| | - Beate Michalzik
- Department of Soil Science, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
| |
Collapse
|
22
|
Tischer A, Machha VR, Frontroth JP, Brehm MA, Obser T, Schneppenheim R, Mayne L, Walter Englander S, Auton M. Enhanced Local Disorder in a Clinically Elusive von Willebrand Factor Provokes High-Affinity Platelet Clumping. J Mol Biol 2017; 429:2161-2177. [PMID: 28533135 DOI: 10.1016/j.jmb.2017.05.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/10/2017] [Accepted: 05/15/2017] [Indexed: 12/19/2022]
Abstract
Mutation of the cysteines forming the disulfide loop of the platelet GPIbα adhesive A1 domain of von Willebrand factor (VWF) causes quantitative VWF deficiencies in the blood and von Willebrand disease. We report two cases of transient severe thrombocytopenia induced by DDAVP treatment. Cys1272Trp and Cys1458Tyr mutations identified by genetic sequencing implicate an abnormal gain-of-function phenotype, evidenced by thrombocytopenia, which quickly relapses back to normal platelet counts and deficient plasma VWF. Using surface plasmon resonance, analytical rheology, and hydrogen-deuterium exchange mass spectrometry (HXMS), we decipher mechanisms of A1-GPIbα-mediated platelet adhesion and resolve dynamic secondary structure elements that regulate the binding pathway. Constrained by the disulfide, conformational selection between weak and tight binding states of A1 takes precedence and drives normal platelet adhesion to VWF. Less restrained through mutation, loss of the disulfide preferentially diverts binding through an induced-fit disease pathway enabling high-affinity GPIbα binding and firm platelet adhesion to a partially disordered A1 domain. HXMS reveals a dynamic asymmetry of flexible and ordered regions common to both variants, indicating that the partially disordered A1 lacking the disulfide retains native-like structural dynamics. Both binding mechanisms share common structural and thermodynamic properties, but the enhanced local disorder in the disease state perpetuates high-affinity platelet agglutination, characteristic of type 2B VWD, upon DDAVP-stimulated secretion of VWF leading to transient thrombocytopenia and a subsequent deficiency of plasma VWF, characteristic of type 2A VWD.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Venkata R Machha
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Juan P Frontroth
- Laboratorio de Hemostasia y Trombosis, Servicio de Hematologia y Oncologia, Hospital de Pediatria, "Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina.
| | - Maria A Brehm
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Tobias Obser
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Reinhard Schneppenheim
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany.
| | - Leland Mayne
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - S Walter Englander
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
| |
Collapse
|
23
|
Blackburn PR, Tischer A, Zimmermann MT, Kemppainen JL, Sastry S, Knight Johnson AE, Cousin MA, Boczek NJ, Oliver G, Misra VK, Gavrilova RH, Lomberk G, Auton M, Urrutia R, Klee EW. A Novel Kleefstra Syndrome-associated Variant That Affects the Conserved TPL X Motif within the Ankyrin Repeat of EHMT1 Leads to Abnormal Protein Folding. J Biol Chem 2017; 292:3866-3876. [PMID: 28057753 PMCID: PMC5339767 DOI: 10.1074/jbc.m116.770545] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/05/2017] [Indexed: 12/26/2022] Open
Abstract
Kleefstra syndrome (KS) (Mendelian Inheritance in Man (MIM) no. 610253), also known as 9q34 deletion syndrome, is an autosomal dominant disorder caused by haploinsufficiency of euchromatic histone methyltransferase-1 (EHMT1). The clinical phenotype of KS includes moderate to severe intellectual disability with absent speech, hypotonia, brachycephaly, congenital heart defects, and dysmorphic facial features with hypertelorism, synophrys, macroglossia, protruding tongue, and prognathism. Only a few cases of de novo missense mutations in EHMT1 giving rise to KS have been described. However, some EHMT1 variants have been described in individuals presenting with autism spectrum disorder or mild intellectual disability, suggesting that the phenotypic spectrum resulting from EHMT1 alterations may be quite broad. In this report, we describe two unrelated patients with complex medical histories consistent with KS in whom next generation sequencing identified the same novel c.2426C>T (p.P809L) missense variant in EHMT1. To examine the functional significance of this novel variant, we performed molecular dynamics simulations of the wild type and p.P809L variant, which predicted that the latter would have a propensity to misfold, leading to abnormal histone mark binding. Recombinant EHMT1 p.P809L was also studied using far UV circular dichroism spectroscopy and intrinsic protein fluorescence. These functional studies confirmed the model-based hypotheses and provided evidence for protein misfolding and aberrant target recognition as the underlying pathogenic mechanism for this novel KS-associated variant. This is the first report to suggest that missense variants in EHMT1 that lead to protein misfolding and disrupted histone mark binding can lead to KS.
Collapse
Affiliation(s)
- Patrick R Blackburn
- From the Center for Individualized Medicine and.,the Department of Health Science Research, Mayo Clinic, Jacksonville, Florida 32224
| | - Alexander Tischer
- the Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology
| | - Michael T Zimmermann
- the Department of Health Science Research, Division of Biomedical Statistics and Informatics
| | | | - Sujatha Sastry
- the Department of Pediatrics, Division of Genetics and Metabolic Disorders, Wayne State University School of Medicine, Detroit, Michigan 48201, and
| | - Amy E Knight Johnson
- the Department of Human Genetics, University of Chicago, Chicago, Illinois 60637
| | - Margot A Cousin
- the Center for Individualized Medicine.,the Department of Health Science Research
| | - Nicole J Boczek
- the Center for Individualized Medicine.,the Department of Health Science Research
| | | | - Vinod K Misra
- the Department of Pediatrics, Division of Genetics and Metabolic Disorders, Wayne State University School of Medicine, Detroit, Michigan 48201, and
| | | | - Gwen Lomberk
- the Laboratory of Epigenetics and Chromatin Dynamics, Epigenomics Translational Program, Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota 55905
| | - Matthew Auton
- the Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology
| | - Raul Urrutia
- the Laboratory of Epigenetics and Chromatin Dynamics, Epigenomics Translational Program, Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota 55905,
| | - Eric W Klee
- the Department of Clinical Genomics, .,the Center for Individualized Medicine.,the Department of Health Science Research
| |
Collapse
|
24
|
Tischer A, Schober T, Karner M, Moser S, Schleicher M, Gschwantler M. A rare complication of endoloop-assisted polypectomy: adhesion of snare and endoloop. Endoscopy 2017; 48 Suppl 1:E117-8. [PMID: 27008561 DOI: 10.1055/s-0042-104278] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Affiliation(s)
- Alexander Tischer
- Wilhelminenspital, Department of Internal Medicine IV, Vienna, Austria
| | - Theresia Schober
- Wilhelminenspital, Department of Internal Medicine IV, Vienna, Austria
| | - Margret Karner
- Wilhelminenspital, Department of Internal Medicine IV, Vienna, Austria
| | - Stephan Moser
- Wilhelminenspital, Department of Internal Medicine IV, Vienna, Austria
| | | | | |
Collapse
|
25
|
Unzué-Belmonte D, Struyf E, Clymans W, Tischer A, Potthast K, Bremer M, Meire P, Schaller J. Fire enhances solubility of biogenic silica. Sci Total Environ 2016; 572:1289-1296. [PMID: 26774130 DOI: 10.1016/j.scitotenv.2015.12.085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 12/03/2015] [Accepted: 12/18/2015] [Indexed: 06/05/2023]
Abstract
Changing fire regimes in response to climate change are likely to have significant effects on terrestrial ecosystems and biogeochemical cycles. While effects of fire on some nutrient cycles have been quite well-studied, little attention has been paid to the silicon cycle. We used an alkaline continuous extraction to examine changes in the quantity and characteristics of alkaline extractable Si (AlkExSi) after applying two burning treatments (no heating, 350°C and 550°C) to three types of organic soil material (from spruce forest, beech forest and a commercial peat). The total AlkExSi measured was 25.1±2.1mgg-1 and 15.4±0.9mgg-1 for spruce and beech respectively, and 1.2±0.5mgg-1 for peat. The alkaline extraction parameters confirm a purely biogenic AlkExSi source in untreated spruce and beech organic soil material samples. Organic soil material of beech forest had two biogenic silica pools, differing in reactivity during alkaline extraction. Burning severely alters the alkaline dissolution parameters suggesting a significant crystallization of biogenic Si (BSi) with increased burning severity. Additionally, dissolution experiments carried out in rain water showed that fire increased the solubility of BSi by a factor of 40 and 20 in the case of the spruce and beech organic soil material respectively. The extent of enhanced Si solubility appears to be a trade-off function between organic matter losses and degree of crystallization. The burned soils could provide a strong and immediate Si source for the environment. In situ ecosystem characteristics that affect the uptake-leaching balance will determine the fate of the dissolved Si. Ecosystems low in BSi, like Sphagnum peatland, will not show drastic alteration in the Si cycle due to fire.
Collapse
Affiliation(s)
- Dácil Unzué-Belmonte
- Ecosystem Management Research Group, Department of Biology, University of Antwerp, Universiteitsplein 1C, 2610 Wilrijk, Belgium.
| | - Eric Struyf
- Ecosystem Management Research Group, Department of Biology, University of Antwerp, Universiteitsplein 1C, 2610 Wilrijk, Belgium
| | - Wim Clymans
- Department of Geology, Lund University, Sölvegaten 12, SE 223 62 Lund, Sweden
| | - Alexander Tischer
- Institute of Soil Science and Site Ecology, Faculty of Environmental Sciences, Technische Universität Dresden, 01737 Tharandt, Germany
| | - Karin Potthast
- Institute of Soil Science, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Martina Bremer
- Institute of Plant and Wood Chemistry, Faculty of Environmental Sciences, Technische Universität Dresden, 01737 Tharandt, Germany
| | - Patrick Meire
- Ecosystem Management Research Group, Department of Biology, University of Antwerp, Universiteitsplein 1C, 2610 Wilrijk, Belgium
| | - Jörg Schaller
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, 95440 Bayreuth, Germany; Institute of General Ecology, Faculty of Environmental Sciences, Technische Universität Dresden, 01737 Tharandt, Germany
| |
Collapse
|
26
|
Machha VR, Tischer A, Moon-Tasson L, Auton M. The Von Willebrand Factor A1-Collagen III Interaction Is Independent of Conformation and Type 2 Von Willebrand Disease Phenotype. J Mol Biol 2016; 429:32-47. [PMID: 27889474 DOI: 10.1016/j.jmb.2016.11.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 11/11/2016] [Accepted: 11/14/2016] [Indexed: 10/20/2022]
Abstract
The blood von Willebrand factor (VWF) mediates platelet adhesion to injured vessels by sequestering platelets from blood flow and depositing them to collagen and other exposed subendothelial matrix proteins. This process of capturing platelets to facilitate formation of platelet plugs occurs through transient interactions with platelet glycoprotein Ibα via the VWF A1 domain which also binds collagen. Using a conformationally diverse collection of natively folded and mutation-induced misfolded von Willebrand disease (VWD) variants, we test a recently proposed affinity up-regulation hypothesis which states that collagen binding changes the conformation of the A1 domain to a high-affinity GPIbα binding competent state. With surface plasmon resonance (SPR), we present this diversified collection to collagen and quantify the kinetics of association and dissociation to ascertain the conformational selectivity of collagen. With analytical rheology, we quantify real-time platelet pause times and translocation velocities across a Cu2+ HisTag-chelated and collagen-bound A1 single domain and A1A2A3 tridomain fragment of VWF under shear stress in an ex vivo shear flow microfluidic chamber. In contrast to expected hypothetical outcomes, collagen has limited conformational selectivity for binding A1. A1-collagen binding is independent of gain- or loss-of-function phenotype and under shear stress, platelet translocation pause times on collagen-bound A1A2A3 are either normal or shorter depending on whether A1 is concertedly bound with the A3 domain to collagen. With respect to A1, collagen has an inhibitory role that provides an explanation for the lack of thrombosis in patients with gain-of-function VWD.
Collapse
Affiliation(s)
- Venkata R Machha
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
| | - Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
| | - Laurie Moon-Tasson
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States.
| |
Collapse
|
27
|
Lea WA, O'Neil PT, Machen AJ, Naik S, Chaudhri T, McGinn-Straub W, Tischer A, Auton MT, Burns JR, Baldwin MR, Khar KR, Karanicolas J, Fisher MT. Chaperonin-Based Biolayer Interferometry To Assess the Kinetic Stability of Metastable, Aggregation-Prone Proteins. Biochemistry 2016; 55:4885-908. [PMID: 27505032 DOI: 10.1021/acs.biochem.6b00293] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Stabilizing the folded state of metastable and/or aggregation-prone proteins through exogenous ligand binding is an appealing strategy for decreasing disease pathologies caused by protein folding defects or deleterious kinetic transitions. Current methods of examining binding of a ligand to these marginally stable native states are limited because protein aggregation typically interferes with analysis. Here, we describe a rapid method for assessing the kinetic stability of folded proteins and monitoring the effects of ligand stabilization for both intrinsically stable proteins (monomers, oligomers, and multidomain proteins) and metastable proteins (e.g., low Tm) that uses a new GroEL chaperonin-based biolayer interferometry (BLI) denaturant pulse platform. A kinetically controlled denaturation isotherm is generated by exposing a target protein, immobilized on a BLI biosensor, to increasing denaturant concentrations (urea or GuHCl) in a pulsatile manner to induce partial or complete unfolding of the attached protein population. Following the rapid removal of the denaturant, the extent of hydrophobic unfolded/partially folded species that remains is detected by an increased level of GroEL binding. Because this kinetic denaturant pulse is brief, the amplitude of binding of GroEL to the immobilized protein depends on the duration of the exposure to the denaturant, the concentration of the denaturant, wash times, and the underlying protein unfolding-refolding kinetics; fixing all other parameters and plotting the GroEL binding amplitude versus denaturant pulse concentration result in a kinetically controlled denaturation isotherm. When folding osmolytes or stabilizing ligands are added to the immobilized target proteins before and during the denaturant pulse, the diminished population of unfolded/partially folded protein manifests as a decreased level of GroEL binding and/or a marked shift in these kinetically controlled denaturation profiles to higher denaturant concentrations. This particular platform approach can be used to identify small molecules and/or solution conditions that can stabilize or destabilize thermally stable proteins, multidomain proteins, oligomeric proteins, and, most importantly, aggregation-prone metastable proteins.
Collapse
Affiliation(s)
- Wendy A Lea
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, Kansas 66160, United States
| | - Pierce T O'Neil
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, Kansas 66160, United States
| | - Alexandra J Machen
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, Kansas 66160, United States
| | - Subhashchandra Naik
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, Kansas 66160, United States
| | | | - Wesley McGinn-Straub
- fortéBIO (a division of Pall Life Sciences) , Menlo Park, California 94025, United States
| | - Alexander Tischer
- Division of Hematology, Department of Internal Medicine, Mayo Clinic , Rochester, Minnesota 55902, United States
| | - Matthew T Auton
- Division of Hematology, Department of Internal Medicine, Mayo Clinic , Rochester, Minnesota 55902, United States
| | - Joshua R Burns
- Department of Molecular Microbiology and Immunology, University of Missouri , Columbia, Missouri 65212, United States
| | - Michael R Baldwin
- Department of Molecular Microbiology and Immunology, University of Missouri , Columbia, Missouri 65212, United States
| | - Karen R Khar
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas , Lawrence, Kansas 66045, United States
| | - John Karanicolas
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas , Lawrence, Kansas 66045, United States
| | - Mark T Fisher
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, Kansas 66160, United States
| |
Collapse
|
28
|
Campbell JC, Tischer A, Machha V, Moon-Tasson L, Sankaran B, Kim C, Auton M. Data on the purification and crystallization of the loss-of-function von Willebrand disease variant (p.Gly1324Ser) of the von Willebrand factor A1 domain. Data Brief 2016; 7:1700-1706. [PMID: 27761512 PMCID: PMC5063811 DOI: 10.1016/j.dib.2016.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 05/02/2016] [Accepted: 05/03/2016] [Indexed: 12/12/2022] Open
Abstract
von Willebrand factor׳s (VWF) primary hemostatic responsibility is to deposit platelets at sites of vascular injury to prevent bleeding. This function is mediated by the interaction between the VWF A1 domain and the constitutively active platelet receptor, GPIbα. The crystal structure of the A1 domain harboring the von Willebrand disease (vWD) type 2M mutation p.Gly1324Ser has been recently published in the Journal of Biological Chemistry describing its effect on the function and structural stability of the A1 domain of VWF, “Mutational constraints on local unfolding inhibit the rheological adaptation of von Willebrand factor” [1]. The mutation introduces a side chain that thermodynamically stabilizes the domain by reducing the overall flexibility of the A1–GPIbα binding interface resulting in loss-of-function and bleeding due to the inability of A1 to adapt to a binding competent conformation under the rheological shear stress blood flow. In this data article we describe the production, quality control and crystallization of the p.Gly1324Ser vWD variant of the A1 domain of VWF. p.Gly1324Ser A1 was expressed in Escherichia coli as insoluble inclusion bodies. After the preparation of the inclusion bodies, the protein was solubilized, refolded, purified by affinity chromatography and crystallized. The crystal structure of the p.Gly1324Ser mutant of the A1 domain is deposited at the Protein Data Bank PDB: 5BV8
Collapse
Affiliation(s)
- James C. Campbell
- Structural and Computational Biology and Molecular Biophysics Program, Baylor College of Medicine, Houston, TX, USA
| | - Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Venkata Machha
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Laurie Moon-Tasson
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Banumathi Sankaran
- Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, BLDG 6R2100, Berkeley, CA, USA
| | - Choel Kim
- Structural and Computational Biology and Molecular Biophysics Program, Baylor College of Medicine, Houston, TX, USA
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
- Corresponding author.
| |
Collapse
|
29
|
Zimmermann MT, Tischer A, Whitten ST, Auton M. Structural origins of misfolding propensity in the platelet adhesive von Willebrand factor A1 domain. Biophys J 2016. [PMID: 26200876 DOI: 10.1016/j.bpj.2015.06.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The von Willebrand factor (VWF) A1 and A3 domains are structurally isomorphic yet exhibit distinct mechanisms of unfolding. The A1 domain, responsible for platelet adhesion to VWF in hemostasis, unfolds through a molten globule intermediate in an apparent three-state mechanism, while A3 unfolds by a classical two-state mechanism. Inspection of the sequences or structures alone does not elucidate the source of this thermodynamic conundrum; however, the three-state character of the A1 domain suggests that it has more than one cooperative substructure yielding two separate unfolding transitions not present in A3. We investigate the extent to which structural elements contributing to intermediate conformations can be identified using a residue-specific implementation of the structure-energy-equivalence-of-domains algorithm (SEED), which parses proteins of known structure into their constituent thermodynamically cooperative components using protein-group-specific, transfer free energies. The structural elements computed to contribute to the non-two-state character coincide with regions where Von Willebrand disease mutations induce misfolded molten globule conformations of the A1 domain. This suggests a mechanism for the regulation of rheological platelet adhesion to A1 based on cooperative flexibility of the α2 and α3 helices flanking the platelet GPIbα receptor binding interface.
Collapse
Affiliation(s)
- Michael T Zimmermann
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Alexander Tischer
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Steven T Whitten
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
| | - Matthew Auton
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota.
| |
Collapse
|
30
|
Tischer A, Campbell JC, Machha VR, Moon-Tasson L, Benson LM, Sankaran B, Kim C, Auton M. Mutational Constraints on Local Unfolding Inhibit the Rheological Adaptation of von Willebrand Factor. J Biol Chem 2015; 291:3848-59. [PMID: 26677223 DOI: 10.1074/jbc.m115.703850] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [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: 11/12/2015] [Indexed: 12/15/2022] Open
Abstract
Unusually large von Willebrand factor (VWF), the first responder to vascular injury in primary hemostasis, is designed to capture platelets under the high shear stress of rheological blood flow. In type 2M von Willebrand disease, two rare mutations (G1324A and G1324S) within the platelet GPIbα binding interface of the VWF A1 domain impair the hemostatic function of VWF. We investigate structural and conformational effects of these mutations on the A1 domain's efficacy to bind collagen and adhere platelets under shear flow. These mutations enhance the thermodynamic stability, reduce the rate of unfolding, and enhance the A1 domain's resistance to limited proteolysis. Collagen binding affinity is not significantly affected indicating that the primary stabilizing effect of these mutations is to diminish the platelet binding efficiency under shear flow. The enhanced stability stems from the steric consequences of adding a side chain (G1324A) and additionally a hydrogen bond (G1324S) to His(1322) across the β2-β3 hairpin in the GPIbα binding interface, which restrains the conformational degrees of freedom and the overall flexibility of the native state. These studies reveal a novel rheological strategy in which the incorporation of a single glycine within the GPIbα binding interface of normal VWF enhances the probability of local unfolding that enables the A1 domain to conformationally adapt to shear flow while maintaining its overall native structure.
Collapse
Affiliation(s)
- Alexander Tischer
- From the Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - James C Campbell
- the Structural and Computational Biology and Molecular Biophysics Program
| | - Venkata R Machha
- From the Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - Laurie Moon-Tasson
- From the Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - Linda M Benson
- the Department of Biochemistry and Molecular Biology, College of Medicine, Mayo Clinic, Rochester, Minnesota 55905, and
| | - Banumathi Sankaran
- the Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Choel Kim
- the Structural and Computational Biology and Molecular Biophysics Program, Department of Pharmacology, and the Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Matthew Auton
- From the Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905,
| |
Collapse
|
31
|
Moser S, Tischer A, Karpi A, Schleicher M, Stavjanik S, Gschwantler M. Evidence that thalidomide is effective in recurrent bleeding from watermelon stomach associated with liver cirrhosis. Endoscopy 2015; 46 Suppl 1 UCTN:E384. [PMID: 25254589 DOI: 10.1055/s-0034-1377369] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Stephan Moser
- Department of Internal Medicine IV, Wilhelminenspital, Vienna, Austria
| | - Alexander Tischer
- Department of Internal Medicine IV, Wilhelminenspital, Vienna, Austria
| | - Asia Karpi
- Department of Internal Medicine IV, Wilhelminenspital, Vienna, Austria
| | | | - Susanne Stavjanik
- Department of Internal Medicine IV, Wilhelminenspital, Vienna, Austria
| | | |
Collapse
|
32
|
Schaller J, Tischer A, Struyf E, Bremer M, Belmonte DU, Potthast K. Fire enhances phosphorus availability in topsoils depending on binding properties. Ecology 2015. [DOI: 10.1890/14-1311.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
33
|
Perez RB, Tischer A, Auton M, Whitten ST. Alanine and proline content modulate global sensitivity to discrete perturbations in disordered proteins. Proteins 2014; 82:3373-84. [PMID: 25244701 DOI: 10.1002/prot.24692] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 08/26/2014] [Accepted: 09/16/2014] [Indexed: 01/12/2023]
Abstract
Molecular transduction of biological signals is understood primarily in terms of the cooperative structural transitions of protein macromolecules, providing a mechanism through which discrete local structure perturbations affect global macromolecular properties. The recognition that proteins lacking tertiary stability, commonly referred to as intrinsically disordered proteins (IDPs), mediate key signaling pathways suggests that protein structures without cooperative intramolecular interactions may also have the ability to couple local and global structure changes. Presented here are results from experiments that measured and tested the ability of disordered proteins to couple local changes in structure to global changes in structure. Using the intrinsically disordered N-terminal region of the p53 protein as an experimental model, a set of proline (PRO) and alanine (ALA) to glycine (GLY) substitution variants were designed to modulate backbone conformational propensities without introducing non-native intramolecular interactions. The hydrodynamic radius (R(h)) was used to monitor changes in global structure. Circular dichroism spectroscopy showed that the GLY substitutions decreased polyproline II (PP(II)) propensities relative to the wild type, as expected, and fluorescence methods indicated that substitution-induced changes in R(h) were not associated with folding. The experiments showed that changes in local PP(II) structure cause changes in R(h) that are variable and that depend on the intrinsic chain propensities of PRO and ALA residues, demonstrating a mechanism for coupling local and global structure changes. Molecular simulations that model our results were used to extend the analysis to other proteins and illustrate the generality of the observed PRO and alanine effects on the structures of IDPs.
Collapse
Affiliation(s)
- Romel B Perez
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas
| | | | | | | |
Collapse
|
34
|
Tischer A, Lilie H, Auton M, Lange C. Oxidative refolding of rPA in l
-ArgHCl and in ionic liquids: A correlation between hydrophobicity, salt effects, and refolding yield. Biopolymers 2014; 101:1129-40. [DOI: 10.1002/bip.22518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 05/09/2014] [Accepted: 06/10/2014] [Indexed: 12/17/2022]
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine; Biochemistry and Molecular Biology, Mayo Clinic; Rochester MN
| | - Hauke Lilie
- Institut für Biochemie und Biotechnologie; Martin-Luther-Universität Halle-Wittenberg; Kurt-Mothes-Str. 3 06120 Halle (Saale) Germany
| | - Matthew Auton
- Division of Hematology, Departments of Internal Medicine; Biochemistry and Molecular Biology, Mayo Clinic; Rochester MN
| | - Christian Lange
- Scil Proteins GmbH; Heinrich Damerow Str. 1 06120 Halle (Saale) Germany
| |
Collapse
|
35
|
Ihling CH, Schröder T, Pettelkau J, Tischer A, Lange C, Sinz A. Accessibilities of N-terminal myristoyl chain and cysteines in guanylyl cyclase-activating protein-2 (GCAP-2) studied by covalent labeling and mass spectrometry. Rapid Commun Mass Spectrom 2014; 28:835-838. [PMID: 24573816 DOI: 10.1002/rcm.6846] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 01/17/2014] [Accepted: 01/19/2014] [Indexed: 06/03/2023]
Affiliation(s)
- Christian H Ihling
- Department of Pharmaceutical Chemistry &Bioanalytics, Institute of Pharmacy, Martin-Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | | | | | | | | | | |
Collapse
|
36
|
Tischer A, Pultke H, Topf A, Auton M, Lange C, Lilie H. The effects ofN-ethyl-N′-methyl imidazolium chloride on the solubility, stability and aggregation of tc-rPA. FEBS J 2014; 281:1738-49. [DOI: 10.1111/febs.12736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/18/2014] [Accepted: 01/29/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Alexander Tischer
- Division of Hematology; Departments of Internal Medicine, Biochemistry and Molecular Biology; Mayo Clinic; Rochester MN USA
| | | | - Andrea Topf
- Institut für Biophysikalische Chemie; Medizinische Hochschule Hannover; Germany
| | - Matthew Auton
- Division of Hematology; Departments of Internal Medicine, Biochemistry and Molecular Biology; Mayo Clinic; Rochester MN USA
| | | | - Hauke Lilie
- Institut für Biochemie und Biotechnologie; Martin-Luther-Universität Halle-Wittenberg; Halle (Saale) Germany
| |
Collapse
|
37
|
Tischer A, Cruz MA, Auton M. The linker between the D3 and A1 domains of vWF suppresses A1-GPIbα catch bonds by site-specific binding to the A1 domain. Protein Sci 2014; 22:1049-59. [PMID: 23775931 DOI: 10.1002/pro.2294] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 06/01/2013] [Accepted: 06/03/2013] [Indexed: 11/11/2022]
Abstract
Platelet attachment to von Willebrand factor (vWF) requires the interaction between the platelet GP1bα and exposed vWF-A1 domains. Structural insights into the mechanism of the A1-GP1bα interaction have been limited to an N-terminally truncated A1 domain that lacks residues Q1238 - E1260 that make up the linker between the D3 and A1 domains of vWF. We have demonstrated that removal of these residues destabilizes quaternary interactions in the A1A2A3 tridomain and contributes to platelet activation under high shear (Auton et al., J Biol Chem 2012;287:14579-14585). In this study, we demonstrate that removal of these residues from the single A1 domain enhances platelet pause times on immobilized A1 under rheological shear. A rigorous comparison between the truncated A1-1261 and full length A1-1238 domains demonstrates a kinetic stabilization of the A1 domain induced by these N-terminal residues as evident in the enthalpy of the unfolding transition. This stabilization occurs through site and sequence-specific binding of the N-terminal peptide to A1. Binding of free N-terminal peptide to A1-1261 has an affinity KD=46±6μM and this binding although free to dissociate is sufficient to suppress the platelet pause times to levels comparable to A1-1238 under shear stress. Our results support a dual-structure/function role for this linker region involving a conformational equilibria that maintains quaternary A domain associations in the inactive state of vWF at low shear and an intra-A1-domain conformation that regulates the strength of platelet GP1bα-vWF A1 domain associations in the active state of vWF at high shear.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA
| | | | | |
Collapse
|
38
|
Tischer A, Madde P, Blancas-Mejia LM, Auton M. A molten globule intermediate of the von Willebrand factor A1 domain firmly tethers platelets under shear flow. Proteins 2013; 82:867-78. [PMID: 24265179 DOI: 10.1002/prot.24464] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 10/23/2013] [Accepted: 10/29/2013] [Indexed: 02/02/2023]
Abstract
Clinical mutations in patients diagnosed with Type 2A von Willebrand disease (VWD) have been identified that break the single disulfide bond linking N- and C-termini in the vWF A1 domain. We have modeled the effect of these mutations on the disulfide-bonded structure of A1 by reducing and carboxy-amidating these cysteines. Solution biophysical studies show that loss of this disulfide bond induces a molten globule conformational state lacking global tertiary structure but retaining residual secondary structure. The conformational dependence of platelet adhesion to these native and molten globule states of A1 is quantitatively compared using real-time high-speed video microscopy analysis of platelet translocation dynamics under shear flow in a parallel plate microfluidic flow chamber. While normal platelets translocating on surface-captured native A1 domain retain the catch-bond character of pause times that increase as a function of shear rate at low shear and decrease as a function of shear rate at high shear, platelets that interact with A1 lacking the disulfide bond remain stably attached and do not translocate. Based on these findings, we propose that the shear stress-sensitive regulation of the A1-GPIb interaction is due to folding the tertiary structure of this domain. Removal of the tertiary structure by disrupting the disulfide bond destroys this regulatory mechanism resulting in high-strength interactions between platelets and vWF A1 that are dependent only on residual secondary structure elements present in the molten globule conformation.
Collapse
Affiliation(s)
- Alexander Tischer
- Departments of Internal Medicine Division of Hematology, Mayo Clinic, Rochester, Minnesota
| | | | | | | |
Collapse
|
39
|
Blancas-Mejía LM, Tischer A, Thompson JR, Tai J, Wang L, Auton M, Ramirez-Alvarado M. Kinetic control in protein folding for light chain amyloidosis and the differential effects of somatic mutations. J Mol Biol 2013; 426:347-61. [PMID: 24157440 DOI: 10.1016/j.jmb.2013.10.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [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: 06/25/2013] [Revised: 08/30/2013] [Accepted: 10/07/2013] [Indexed: 10/26/2022]
Abstract
Light chain amyloidosis is a devastating disease where immunoglobulin light chains form amyloid fibrils, resulting in organ dysfunction and death. Previous studies have shown a direct correlation between the protein thermodynamic stability and the propensity for amyloid formation for some proteins involved in light chain amyloidosis. Here we investigate the effect of somatic mutations on protein stability and in vitro fibril formation of single and double restorative mutants of the protein AL-103 compared to the wild-type germline control protein. A scan rate dependence and hysteresis in the thermal unfolding and refolding was observed for all proteins. This indicates that the unfolding/refolding reaction is kinetically determined with different kinetic constants for unfolding and refolding even though the process remains experimentally reversible. Our structural analysis of AL-103 and AL-103 delP95aIns suggests a kinetic coupling of the unfolding/refolding process with cis-trans prolyl isomerization. Our data reveal that the deletion of proline 95a (AL-103 delP95aIns), which removes the trans-cis di-proline motif present in the patient protein AL-103, results in a dramatic increment in the thermodynamic stability and a significant delay in fibril formation kinetics with respect to AL-103. Fibril formation is pH dependent; all proteins form fibrils at pH2; reactions become slower and more stochastic as the pH increases up to pH7. Based on these results, we propose that, in addition to thermodynamic stability, kinetic stability (possibly influenced by the presence of cis proline 95a) plays a major role in the AL-103 amyloid fibril formation process.
Collapse
Affiliation(s)
- Luis M Blancas-Mejía
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Alexander Tischer
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA; Division of Hematology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - James R Thompson
- Department of Physiology and Biomedical Engineering, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Jonathan Tai
- Department of Chemistry, University of Illinois, Urbana, IL 61801, USA
| | - Lin Wang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Matthew Auton
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA; Division of Hematology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Marina Ramirez-Alvarado
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.
| |
Collapse
|
40
|
Tischer A, Auton M. Urea-temperature phase diagrams capture the thermodynamics of denatured state expansion that accompany protein unfolding. Protein Sci 2013; 22:1147-60. [PMID: 23813497 PMCID: PMC3776328 DOI: 10.1002/pro.2301] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 06/18/2013] [Accepted: 06/18/2013] [Indexed: 11/11/2022]
Abstract
We have analyzed the thermodynamic properties of the von Willebrand factor (VWF) A3 domain using urea-induced unfolding at variable temperature and thermal unfolding at variable urea concentrations to generate a phase diagram that quantitatively describes the equilibrium between native and denatured states. From this analysis, we were able to determine consistent thermodynamic parameters with various spectroscopic and calorimetric methods that define the urea-temperature parameter plane from cold denaturation to heat denaturation. Urea and thermal denaturation are experimentally reversible and independent of the thermal scan rate indicating that all transitions are at equilibrium and the van't Hoff and calorimetric enthalpies obtained from analysis of individual thermal transitions are equivalent demonstrating two-state character. Global analysis of the urea-temperature phase diagram results in a significantly higher enthalpy of unfolding than obtained from analysis of individual thermal transitions and significant cross correlations describing the urea dependence of ΔH0 and ΔCP0 that define a complex temperature dependence of the m-value. Circular dichroism (CD) spectroscopy illustrates a large increase in secondary structure content of the urea-denatured state as temperature increases and a loss of secondary structure in the thermally denatured state upon addition of urea. These structural changes in the denatured ensemble make up ∼40% of the total ellipticity change indicating a highly compact thermally denatured state. The difference between the thermodynamic parameters obtained from phase diagram analysis and those obtained from analysis of individual thermal transitions illustrates that phase diagrams capture both contributions to unfolding and denatured state expansion and by comparison are able to decipher these contributions.
Collapse
Affiliation(s)
- Alexander Tischer
- Division of Hematology, Departments of Internal Medicine and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | | |
Collapse
|
41
|
Schwarzer R, Tischer A, Dulic M, Dulic-Lakovic E, Assadi S, Gschwantler M. Forty years without symptoms after choledochogastrostomy. Endoscopy 2012; 44 Suppl 2 UCTN:E199-200. [PMID: 22622743 DOI: 10.1055/s-0032-1306902] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Affiliation(s)
- R Schwarzer
- 4th Department of Internal Medicine, Wilhelminenspital, Vienna, Austria
| | | | | | | | | | | |
Collapse
|
42
|
Tischer A, Lilie H, Rudolph R, Lange C. L-arginine hydrochloride increases the solubility of folded and unfolded recombinant plasminogen activator rPA. Protein Sci 2010; 19:1783-95. [PMID: 20665695 PMCID: PMC2975141 DOI: 10.1002/pro.465] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [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: 05/18/2010] [Revised: 07/07/2010] [Accepted: 07/07/2010] [Indexed: 11/06/2022]
Abstract
L-arginine hydrochloride (L-ArgHCl) was found to be an effective enhancer for in vitro protein refolding more than two decades ago. A detailed understanding of the mechanism of action, by which L-ArgHCl as co-solvent is capable to effectively suppress protein aggregation, while protein stability is preserved, has remained elusive. Concepts for the effects of co-solvents, which have been established over the last decades, were found to be insufficient to completely explain the effects of L-ArgHCl on protein refolding. In this article, we present data, which clearly establish that L-ArgHCl acts on the equilibrium solubility of the native model protein recombinant plasminogen activator (rPA), while for S-carboxymethylated rPA (IAA-rPA) that served as a model protein for denatured protein states, equilibrium solubilities could not be obtained. Solid to solute free transfer energies for native rPA were lowered by up to 14 kJ mol(-1) under the tested conditions. This finding is in marked contrast to a previously proposed model in which L-ArgHCl acts as a neutral crowder which exclusively has an influence on the stability of the transition state of aggregation. The effects on the apparent solubility of IAA-rPA, as well as on the aggregation kinetics of all studied protein species, that were observed in the present work could tentatively be explained within the framework of a nucleation-aggregation scheme, in which L-ArgHCl exerts a strong effect on the pre-equilibria leading to formation of the aggregation seed.
Collapse
Affiliation(s)
| | | | | | - Christian Lange
- Institut für Biochemie und Biotechnologie, Martin-Luther-Universität Halle-WittenbergKurt-Mothes-Str. 3, 06120 Halle (Saale), Germany
| |
Collapse
|
43
|
Bruns CJ, Herrmann P, Huber S, Tischer A, Hesler CV, Luckner M, Jauch KW, Heeschen C. Identifikation und Charakterisierung von hoch-metastatischen und therapie-resistenten Tumorstammzellen beim Pankreaskarzinom. Z Gastroenterol 2007. [DOI: 10.1055/s-2007-992760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
44
|
Nardone A, de Ory F, Carton M, Cohen D, van Damme P, Davidkin I, Rota MC, de Melker H, Mossong J, Slacikova M, Tischer A, Andrews N, Berbers G, Gabutti G, Gay N, Jones L, Jokinen S, Kafatos G, de Aragón MVM, Schneider F, Smetana Z, Vargova B, Vranckx R, Miller E. The comparative sero-epidemiology of varicella zoster virus in 11 countries in the European region. Vaccine 2007; 25:7866-72. [PMID: 17919788 DOI: 10.1016/j.vaccine.2007.07.036] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 05/30/2007] [Accepted: 07/15/2007] [Indexed: 10/23/2022]
Abstract
The European sero-epidemiology network (ESEN2) aims to standardise serological surveillance of varicella zoster virus (VZV) in 11 participant countries. In each country, serum banks were collected between 1996 and 2003 and tested for VZV antibodies. Assay results were standardised so that international comparisons could be made. Age-specific forces of infection were calculated for three age groups (<5, 5-9 and >or=10 years of age) and used to estimate the base reproduction number (R(0)) and the herd immunity threshold (H). Most VZV infection occurred in childhood, but there was a wide variation in transmissibility, with R(0) ranging from 16.9 in the Netherlands to 3.3 in Italy. Herd immunity thresholds varied from 70% in Italy to 94% in the Netherlands. There are substantial differences in VZV sero-epidemiology within the European region, which will need to be taken into account in designing national policies regarding VZV vaccination.
Collapse
Affiliation(s)
- A Nardone
- Health Protection Agency, Centre for Infections, London, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Tischer A, Andrews N, Kafatos G, Nardone A, Berbers G, Davidkin I, Aboudy Y, Backhouse J, Barbara C, Bartha K, Bruckova B, Duks A, Griskevicius A, Hesketh L, Johansen K, Jones L, Kuersteiner O, Lupulescu E, Mihneva Z, Mrazova M, De Ory F, Prosenc K, Schneider F, Tsakris A, Smelhausova M, Vranckx R, Zarvou M, Miller E. Standardization of measles, mumps and rubella assays to enable comparisons of seroprevalence data across 21 European countries and Australia. Epidemiol Infect 2007; 135:787-97. [PMID: 17394675 PMCID: PMC2870639 DOI: 10.1017/s0950268807008266] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2007] [Indexed: 11/07/2022] Open
Abstract
The aim of the European Sero-Epidemiology Network is to establish comparability of the serological surveillance of vaccine-preventable diseases in Europe. The designated reference laboratory (RL) for measles, mumps, rubella (MMR) prepared and tested a panel of 151 sera by the reference enzyme immunoassay (rEIA). Laboratories in 21 countries tested the panel for antibodies against MMR using their usual assay (a total of 16 different EIAs) and the results were plotted against the reference results in order to obtain equations for the standardization of national serum surveys. The RL also tested the panel by the plaque neutralization test (PNT). Large differences in qualitative results were found compared to the RL. Well-fitting standardization equations with R2> or =0.8 were obtained for almost all laboratories through regression of the quantitative results against those of the RL. When compared to PNT, the rEIA had a sensitivity of 95.3%, 92.8% and 100% and a specificity of 100%, 87.1% and 92.8% for measles, mumps and rubella, respectively. The need for standardization was highlighted by substantial inter-country differences. Standardization was successful and the selected standardization equations allowed the conversion of local serological results into common units and enabled direct comparison of seroprevalence data of the participating countries.
Collapse
Affiliation(s)
- A Tischer
- Robert Koch Institute, Berlin, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Hoppe B, Beck B, Gatter N, von Unruh G, Tischer A, Hesse A, Laube N, Kaul P, Sidhu H. Oxalobacter formigenes: a potential tool for the treatment of primary hyperoxaluria type 1. Kidney Int 2006; 70:1305-11. [PMID: 16850020 DOI: 10.1038/sj.ki.5001707] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Primary hyperoxaluria is characterized by severe urolithiasis, nephrocalcinosis, and early renal failure. As treatment options are scarce, we aimed for a new therapeutic tool using colonic degradation of endogenous oxalate by Oxalobactor formigenes. Oxalobacter was orally administered for 4 weeks as frozen paste (IxOC-2) or as enteric-coated capsules (IxOC-3). Nine patients (five with normal renal function, one after liver-kidney transplantation, and three with renal failure) completed the IxOC-2 study. Seven patients (six with normal renal function and one after liver-kidney transplantation) completed the IxOC-3 study. Urinary oxalate or plasma oxalate in renal failure was determined at baseline, weekly during treatment and for a 2-week follow-up. The patients who showed >20% reduction both at the end of weeks 3 and 4 were considered as responders. Under IxOC-2, three out of five patients with normal renal function showed a 22-48% reduction of urinary oxalate. In addition, two renal failure patients experienced a significant reduction in plasma oxalate and amelioration of clinical symptoms. Under IxOC-3 treatment, four out of six patients with normal renal function responded with a reduction of urinary oxalate ranging from 38.5 to 92%. Although all subjects under IxOC-2 and 4 patients under IxOC-3 showed detectable levels of O. formigenes in stool during treatment, fecal recovery dropped directly at follow up, indicating only transient gastrointestinal-tract colonization. The preliminary data indicate that O. formigenes is safe, leads to a significant reduction of either urinary or plasma oxalate, and is a potential new treatment option for primary hyperoxaluria.
Collapse
Affiliation(s)
- B Hoppe
- Division of Pediatric Nephrology, University Children's Hospital Cologne, Cologne, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Abstract
Measles re-emerged in some counties in Germany in 2005, despite increasing vaccination coverage rates in children at school entry in recent years, which had led to decreasing incidence (with the lowest incidence ever recorded, 0.2 cases per 100 000 inhabitants in 2004).
Regional outbreaks have been detected by the mandatory reporting system in the states of Hesse and Bavaria. Although both outbreaks led to similar incidences in the affected areas (14 and 12 cases respectively per 100 000 inhabitants) they differed in age distribution, transmission patterns and measles virus genotype.
In Hesse, 223 cases were submitted, from which 160 belonged to 41 clusters mainly defined by family or household contacts. Attack rate was highest in children aged between 1-4 years (102 cases per 100 000). Results of measles virus diagnosis showed genotype D4 and identical nucleotide sequences for all analysed cases from Hesse.
In Bavaria, 279 cases were submitted, most of which had occurred in schools and preschool facilities. Age-specific attack rate was highest in children aged between 5-9 years (129 per 100 000). Laboratory diagnosed viruses were identified as genotype D6 and were identical at the nucleotide level.
In both outbreaks the vast majority of cases (95% in Hesse and 98% in Bavaria) were in unvaccinated children, but vaccination coverage differed in the affected areas and was slightly lower in Bavaria than in Hesse. Local accumulation of unvaccinated children and their concentration in schools and kindergarten preceded the outbreak in Bavaria.
Despite high average vaccination coverage levels, local variations may lead to regionally limited outbreaks.
Collapse
Affiliation(s)
- A Siedler
- Robert Koch-Institut, Berlin, Germany
| | - A Tischer
- National Reference Centre for Measles, Mumps and Rubella, Department of Viral Infections, Robert Koch-Institut, Berlin, Germany
| | - A Mankertz
- National Reference Centre for Measles, Mumps and Rubella, Department of Viral Infections, Robert Koch-Institut, Berlin, Germany
| | - S Santibanez
- National Reference Centre for Measles, Mumps and Rubella, Department of Viral Infections, Robert Koch-Institut, Berlin, Germany
| |
Collapse
|
48
|
Siedler A, Tischer A, Mankertz A, Santibanez S. Two outbreaks of measles in Germany 2005. Euro Surveill 2006; 11:131-4. [PMID: 16645244] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023] Open
Abstract
Measles re-emerged in some counties in Germany in 2005, despite increasing vaccination coverage rates in children at school entry in recent years, which had led to decreasing incidence (with the lowest incidence ever recorded, 0.2 cases per 100,000 inhabitants in 2004). Regional outbreaks have been detected by the mandatory reporting system in the states of Hesse and Bavaria. Although both outbreaks led to similar incidences in the affected areas (14 and 12 cases respectively per 100,000 inhabitants) they differed in age distribution, transmission patterns and measles virus genotype. In Hesse, 223 cases were submitted, from which 160 belonged to 41 clusters mainly defined by ,000). Results of measles virus diagnosis showed genotype D4 and identical nucleotide sequences for all analysed cases from Hesse. In Bavaria, 279 cases were submitted, most of which had occurred in schools and preschool facilities. Age-specific attack rate was highest in children aged between 5-9 years (129 per 100,000). Laboratory diagnosed viruses were identified as genotype D6 and were identical at the nucleotide level. In both outbreaks the vast majority of cases (95% in Hesse and 98% in Bavaria) were in unvaccinated children, but vaccination coverage differed in the affected areas and was slightly lower in Bavaria than in Hesse. Local accumulation of unvaccinated children and their concentration in schools and kindergarten preceded the outbreak in Bavaria. Despite high average vaccination coverage levels, local variations may lead to regionally limited outbreaks.
Collapse
Affiliation(s)
- A Siedler
- Respiratory Diseases and Immunization group, Department for Infectious Disease Epidemiology, Robert Koch-Institut, Berlin, Germany
| | | | | | | |
Collapse
|
49
|
Pebody RG, Gay NJ, Giammanco A, Baron S, Schellekens J, Tischer A, Olander RM, Andrews NJ, Edmunds WJ, Lecoeur H, Lévy-Bruhl D, Maple PAC, de Melker H, Nardone A, Rota MC, Salmaso S, Conyn-van Spaendonck MAE, Swidsinski S, Miller E. The seroepidemiology of Bordetella pertussis infection in Western Europe. Epidemiol Infect 2005; 133:159-71. [PMID: 15724723 PMCID: PMC2870234 DOI: 10.1017/s0950268804003012] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
High titres of pertussis toxin (PT) antibody have been shown to be predictive of recent infection with Bordetella pertussis. The seroprevalence of standardized anti-PT antibody was determined in six Western European countries between 1994 and 1998 and related to historical surveillance and vaccine programme data. Standardized anti-PT titres were calculated for a series of whole-cell and acellular pertussis vaccine trials. For the serological surveys, high-titre sera (> 125 units/ml) were distributed throughout all age groups in both high- (> 90%) and low-coverage (< 90%) countries. High-titre sera were more likely in infants in countries using high-titre-producing vaccines in their primary programme (Italy, 11.5%; Western Germany, 13.3%; France, 4.3%; Eastern Germany, 4.0%) compared to other countries (The Netherlands, 0.5%; Finland, 0%). Recent infection was significantly more likely in adolescents (10-19 years old) and adults in high-coverage countries (Finland, The Netherlands, France, East Germany), whereas infection was more likely in children (3-9 years old) than adolescents in low-coverage (< 90%; Italy, West Germany, United Kingdom) countries. The impact and role of programmatic changes introduced after these surveys aimed at protecting infants from severe disease by accelerating the primary schedule or vaccinating older children and adolescents with booster doses can be evaluated with this approach.
Collapse
Affiliation(s)
- R G Pebody
- Immunisation Department, Health Protection Agency (HPA) Communicable Disease Surveillance Centre, London, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Giammanco A, Chiarini A, Maple PAC, Andrews N, Pebody R, Gay N, Olander RM, Fivet-Groyne F, Baron S, Tischer A, Swidsinski S, Schellekens J, Reizenstein E. European Sero-Epidemiology Network: standardisation of the assay results for pertussis. Vaccine 2004; 22:112-20. [PMID: 14604578 DOI: 10.1016/s0264-410x(03)00514-0] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A standardisation process was developed in order to compare and harmonize serological results of pertussis toxin (PT) antibody measurements performed by laboratories using different technical procedures for detection. This involved the development of a common panel, of sera by a designed reference centre, the distribution of the panel to each participating laboratory for testing with their routine methods, the comparison of the obtained results to those of the reference centre, and the calculation of standardisation equations by regressing the quantitative results against those of the reference centre. As a cut-off indicative of protection against pertussis has not yet been defined, a particular emphasis was laid upon achieving standardisation of high titre results that would allow epidemiological evaluations based on the estimation of the incidence of recent infections rather than on the traditional approach of determining the population immunity profile. A generally good agreement was achieved between the participating laboratories, all using ELISA procedures very similar in many crucial aspects, and standardisation equations were produced useful to enable inter-country comparison during the next stages of the European Sero-Epidemiology Network (ESEN) project concerning the serological surveillance of immunity to pertussis in Europe.
Collapse
Affiliation(s)
- A Giammanco
- Department of Hygiene and Microbiology, University of Palermo, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|