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Ju I, Elhindi J, Hook M, Melov SJ, Sawleshwarkar S, Yapa HM, Zablotska I, Pasupathy D. Sexually transmitted infections: Prevalence and clinical outcomes among pregnant women in Western Sydney. Int J Gynaecol Obstet 2024. [PMID: 38654697 DOI: 10.1002/ijgo.15548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 03/18/2024] [Accepted: 04/05/2024] [Indexed: 04/26/2024]
Abstract
OBJECTIVE We report the prevalence, characteristics and clinical outcomes of women with sexually transmitted infections (STIs) in pregnancy in the Western Sydney Local Health District (WSLHD) serving a large culturally and socio-economically diverse community in New South Wales (NSW), Australia, over the last 10 years. METHODS A retrospective cohort study of all pregnant women booked for antenatal care at three hospitals in WSLHD between September 2012 and August 2022 inclusive. Characteristics and birth outcomes associated with STIs diagnosed in pregnancy (chlamydia, gonorrhea, and syphilis) are reported using multivariable logistic regression adjusting for relevant confounders. RESULTS During 2012-2022, there were 102 905 births and 451 women (0.44%) with an STI diagnosis during pregnancy. The number of women with a history of chlamydia prior to their current pregnancy has increased over the last 10 years (P < 0.001). STIs in pregnancy were more common in younger women aged <20 years (adjusted odds ratio [aOR] 7.30, 95% confidence interval [CI] 5.04-10.57), 20-24 years (aOR 3.12, 95% CI 2.46-3.96), and >40 years (adj OR 1.67, 95% CI 1.07-2.59), in women with body mass index >30 (aOR 1.73, 95%CI 1.37-2.19), and those who smoked (aOR 2.24, 95% CI 1.71-2.94) and consumed alcohol (aOR 3.14, 95% CI 1.88-5.23) and illicit drugs (aOR 2.10, 95% CI 1.31-3.36). STIs in pregnancy were borderline associated with stillbirth (aOR 2.19 95% CI 0.90-5.36) but did not have a significant impact on preterm birth (aOR 1.21, 95% CI 0.87-1.68), admission to neonatal intensive care unit (NICU) (aOR 1.02, 95% CI 0.77-1.34), or having a small-for-gestational-age (SGA) baby (aOR 0.97, 95% CI 0.74-1.27). CONCLUSIONS Sociodemographic factors such as age, weight, smoking, and alcohol and drug use, were associated with the STI incidence in pregnancy. While the latter did not have an impact on preterm birth, NICU admission, and SGA in our cohort, there was a borderline association with stillbirth. Future research should identify barriers and facilitators to testing in a multicultural population and understanding the drivers of higher rates of STIs in certain population groups.
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Affiliation(s)
- I Ju
- Reproduction and Perinatal Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
- Department of Obstetrics and Gynaecology, Westmead Hospital, Sydney, New South Wales, Australia
| | - J Elhindi
- Reproduction and Perinatal Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - M Hook
- Department of Obstetrics and Gynaecology, Westmead Hospital, Sydney, New South Wales, Australia
| | - S J Melov
- Reproduction and Perinatal Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
- Westmead Institute of Maternal Fetal Medicine, Westmead Hospital, Sydney, New South Wales, Australia
| | - S Sawleshwarkar
- Western Sydney Sexual Health Centre, Sydney, New South Wales, Australia
| | - H M Yapa
- Sydney Infectious Diseases Institute, Faculty of Medicine & Health, University of Sydney, Sydney, New South Wales, Australia
| | - I Zablotska
- Western Sydney Sexual Health Centre, Sydney, New South Wales, Australia
| | - D Pasupathy
- Reproduction and Perinatal Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
- Westmead Institute of Maternal Fetal Medicine, Westmead Hospital, Sydney, New South Wales, Australia
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Gstöttner C, Lippold S, Hook M, Yang F, Haberger M, Wuhrer M, Falck D, Schlothauer T, Domínguez-Vega E. Benchmarking glycoform-resolved affinity separation - mass spectrometry assays for studying FcγRIIIa binding. Front Immunol 2024; 15:1347871. [PMID: 38469305 PMCID: PMC10925690 DOI: 10.3389/fimmu.2024.1347871] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/05/2024] [Indexed: 03/13/2024] Open
Abstract
The antibody- FcγRIIIa interaction triggers key immunological responses such as antibody dependent cellular cytotoxicity (ADCC), making it highly important for therapeutic mAbs. Due to the direct glycan-glycan interaction with FcγRIIIa receptor, differences in antibody glycosylation can drastically influence the binding affinity. Understanding the differential binding of mAb glycoforms is a very important, yet challenging task due to the co-existence of multiple glycoforms in a sample. Affinity liquid chromatography (AC) and affinity capillary electrophoresis (ACE) hyphenated with mass spectrometry (MS) can provide glycoform-resolved affinity profiles of proteins based on their differences in either dissociation (AC) or equilibrium (ACE) constants. To cross-validate the affinity ranking provided by these complementary novel approaches, both techniques were benchmarked using the same FcγRIIIa constructs. Both approaches were able to assess the mAb - FcγRIIIa interaction in a glycoform selective manner and showed a clear increase in binding for fully versus hemi-fucosylated mAbs. Also, other features, such as increasing affinity with elevated galactosylation or the binding affinity for high mannose glycoforms were consistent. We further applied these approaches to assess the binding towards the F158 allotype of FcγRIIIa, which was not reported before. The FcγRIIIa F158 allotype showed a very similar profile compared to the V158 receptor with the strongest increase in binding due to afucosylation and only a slight increase in binding with additional galactosylation. Both techniques showed a decrease of the binding affinity for high mannose glycoforms for FcγRIIIa F158 compared to the V158 variant. Overall, both approaches provided very comparable results in line with orthogonal methods proving the capabilities of separation-based affinity approaches to study FcγR binding of antibody glycoforms.
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Affiliation(s)
- Christoph Gstöttner
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Steffen Lippold
- Protein Analytical Chemistry, Genentech, A Member of the Roche Group, South San Francisco, CA, United States
| | - Michaela Hook
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg, Germany
| | - Feng Yang
- Protein Analytical Chemistry, Genentech, A Member of the Roche Group, South San Francisco, CA, United States
| | - Markus Haberger
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg, Germany
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - David Falck
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Tilman Schlothauer
- Pharma Research and Early Development, Roche Innovation Center, Munich, Germany
| | - Elena Domínguez-Vega
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
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Lippold S, Hook M, Spick C, Knaupp A, Whang K, Ruperti F, Cadang L, Andersen N, Vogt A, Grote M, Reusch D, Haberger M, Yang F, Schlothauer T. CD3 Target Affinity Chromatography Mass Spectrometry as a New Tool for Function-Structure Characterization of T-Cell Engaging Bispecific Antibody Proteoforms and Product-Related Variants. Anal Chem 2023; 95:2260-2268. [PMID: 36638115 DOI: 10.1021/acs.analchem.2c03827] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
T-cell engaging bispecific antibodies (TCBs) targeting CD3 and tumor-specific antigens are very promising therapeutic modalities. Since CD3 binding is crucial for the potency of TCBs, understanding the functional impact of CD3 antigen-binding fragment modifications is of utmost importance for defining critical quality attributes (CQA). The current CQA assessment strategy requires the integration of structure-based physicochemical separation and functional cell-based potency assays. However, this strategy is tedious, and coexisting proteoforms with potentially different functionalities may not be individually assessed. This increases the degree of ambiguities for defining meaningful CQAs, particularly for complex bispecific antibody formats such as TCBs. Here, we report for the first time a proof-of-concept study to separate and identify critically modified proteoforms of TCBs using functional CD3 target affinity chromatography (AC) coupled with online mass spectrometry (MS). Our method enabled functional distinction of relevant deamidated and glycosylated proteoforms and the simultaneous assessment of product-related variants such as TCB mispairings. For example, CD3 AC-MS allowed us to separate TCB mispairings with increased CD3 binding (i.e., knob-knob homodimers) within the bound fraction. The functional separation of proteoforms was validated using an established workflow for CQA identification based on thoroughly characterized ion-exchange fractions of a 2+1 TCB. In addition, the new method facilitated the criticality assessment of post-translational modifications in stress studies and structural variants in early stage clone selection. CD3 AC-MS has high impact for streamlining the integration of functional and structural characterizations of the large landscape of therapeutic CD3 targeting TCBs from early stage research to late stage characterization.
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Affiliation(s)
- Steffen Lippold
- Protein Analytical Chemistry, Genentech, A Member of the Roche Group, 1 DNA Way, South San Francisco, California 94080, United States
| | - Michaela Hook
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg 82377, Germany
| | - Christian Spick
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Alexander Knaupp
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Kevin Whang
- Biological Technologies, Genentech, A Member of the Roche Group, 1 DNA Way, South San Francisco, California 94080, United States
| | - Fabian Ruperti
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Lance Cadang
- Protein Analytical Chemistry, Genentech, A Member of the Roche Group, 1 DNA Way, South San Francisco, California 94080, United States
| | - Nisana Andersen
- Protein Analytical Chemistry, Genentech, A Member of the Roche Group, 1 DNA Way, South San Francisco, California 94080, United States
| | - Annette Vogt
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Michael Grote
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Dietmar Reusch
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg 82377, Germany
| | - Markus Haberger
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg 82377, Germany
| | - Feng Yang
- Protein Analytical Chemistry, Genentech, A Member of the Roche Group, 1 DNA Way, South San Francisco, California 94080, United States
| | - Tilman Schlothauer
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
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Cramer DAT, Franc V, Heidenreich AK, Hook M, Adibzadeh M, Reusch D, Heck AJR, Haberger M. Characterization of high-molecular weight by-products in the production of a trivalent bispecific 2+1 heterodimeric antibody. MAbs 2023; 15:2175312. [PMID: 36799476 PMCID: PMC9980510 DOI: 10.1080/19420862.2023.2175312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
The development of increasingly complex antibody formats, such as bispecifics, can lead to the formation of increasingly complex high- and low-molecular-weight by-products. Here, we focus on the characterization of high molecular weight species (HMWs) representing the highest complexity of size variants. Standard methods used for product release, such as size exclusion chromatography (SEC), can separate HMW by-products from the main product, but cannot distinguish smaller changes in mass. Here, for the identification of the diverse and complex HMW variants of a trivalent bispecific CrossMAb antibody, offline fractionation, as well as production of HMW by-products combined with comprehensive analytical testing, was applied. Furthermore, HMW variants were analyzed regarding their chemical binding nature and tested in functional assays regarding changes in potency of the variants. Changes in potency were explained by detailed characterization using mass photometry, SDS-PAGE analysis, native mass spectrometry (MS) coupled to SEC and bottom-up proteomics. We identified a major portion of the HMW by-products to be non-covalently linked, leading to dissociation and changes in activity. We also identified and localized high heterogeneity of a by-product of concern and applied a CD3 affinity column coupled to native MS to annotate unexpected by-products. We present here a multi-method approach for the characterization of complex HMW by-products. A better understanding of these by-products is beneficial to guide analytical method development and proper specification setting for therapeutic bispecific antibodies to ensure constant efficacy and patient safety of the product through the assessment of by-products.
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Affiliation(s)
- Dario A T Cramer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | | | - Michaela Hook
- Pharma Technical Development, Roche Diagnostics GmbH, Penzberg, Germany
| | - Mahdi Adibzadeh
- Pharma Technical Development, F. Hoffmann-La Roche AG, Basel, Switzerland
| | - Dietmar Reusch
- Pharma Technical Development, Roche Diagnostics GmbH, Penzberg, Germany
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Markus Haberger
- Pharma Technical Development, Roche Diagnostics GmbH, Penzberg, Germany
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Gstöttner C, Hook M, Christopeit T, Knaupp A, Schlothauer T, Reusch D, Haberger M, Wuhrer M, Domínguez-Vega E. Affinity Capillary Electrophoresis-Mass Spectrometry as a Tool to Unravel Proteoform-Specific Antibody-Receptor Interactions. Anal Chem 2021; 93:15133-15141. [PMID: 34739220 PMCID: PMC8600502 DOI: 10.1021/acs.analchem.1c03560] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 11/28/2022]
Abstract
Monoclonal antibody (mAb) pharmaceuticals consist of a plethora of different proteoforms with different functional characteristics, including pharmacokinetics and pharmacodynamics, requiring their individual assessment. Current binding techniques do not distinguish between coexisting proteoforms requiring tedious production of enriched proteoforms. Here, we have developed an approach based on mobility shift-affinity capillary electrophoresis-mass spectrometry (ACE-MS), which permitted us to determine the binding of coexisting mAb proteoforms to Fc receptors (FcRs). For high-sensitivity MS analysis, we used a sheathless interface providing adequate mAb sensitivity allowing functional characterization of mAbs with a high sensitivity and dynamic range. As a model system, we focused on the interaction with the neonatal FcR (FcRn), which determines the half-life of mAbs. Depending on the oxidation status, proteoforms exhibited different electrophoretic mobility shifts in the presence of FcRn, which could be used to determine their affinity. We confirmed the decrease of the FcRn affinity with antibody oxidation and observed a minor glycosylation effect, with higher affinities for galactosylated glycoforms. Next to relative binding, the approach permits the determination of individual KD values in solution resulting in values of 422 and 139 nM for double-oxidized and non-oxidized variants. Hyphenation with native MS provides unique capabilities for simultaneous heterogeneity assessment for mAbs, FcRn, and complexes formed. The latter provides information on binding stoichiometry revealing 1:1 and 1:2 for antibody/FcRn complexes. The use of differently engineered Fc-only constructs allowed distinguishing between symmetric and asymmetric binding. The approach opens up unique possibilities for proteoform-resolved antibody binding studies to FcRn and can be extended to other FcRs and protein interactions.
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Affiliation(s)
- Christoph Gstöttner
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden 2333ZA, The Netherlands
| | - Michaela Hook
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg 82377, Germany
| | - Tony Christopeit
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Alexander Knaupp
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Tilman Schlothauer
- Pharma Research and Early Development, Roche Innovation Center Munich, Penzberg 82377, Germany
| | - Dietmar Reusch
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg 82377, Germany
| | - Markus Haberger
- Pharma Technical Development Penzberg, Roche Diagnostics GmbH, Penzberg 82377, Germany
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden 2333ZA, The Netherlands
| | - Elena Domínguez-Vega
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden 2333ZA, The Netherlands
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Haberger M, Heidenreich AK, Hook M, Fichtl J, Lang R, Cymer F, Adibzadeh M, Kuhne F, Wegele H, Reusch D, Bonnington L, Bulau P. Multiattribute Monitoring of Antibody Charge Variants by Cation-Exchange Chromatography Coupled to Native Mass Spectrometry. J Am Soc Mass Spectrom 2021; 32:2062-2071. [PMID: 33687195 DOI: 10.1021/jasms.0c00446] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The aim of this study was to characterize the product variants of a therapeutic T-cell bispecific humanized monoclonal antibody (TCB Mab, ∼200 kDa, asymmetric) and to develop an online cation-exchange chromatography native electrospray mass spectrometry method (CEC-UV-MS) for direct TCB Mab charge variant monitoring during bioprocess and formulation development. For the identification and functional evaluation of the diverse and complex TCB Mab charge variants, offline fractionation combined with comprehensive analytical testing was applied. The offline fractionation of abundant product variant peaks enabled identification of coeluting acid charge variants such as asparagine deamidation, primary and secondary Fab glycosylation (with and without sialic acid), and the presence of O-glycosylation in the G4S-linker region. Consequently, a new nonconsensus N-glycosylation motif (N-338-FG) in the heavy chain CDR region was discovered. Functional evaluation by cell-based potency testing demonstrated a clear and negative impact of both asparagine deamidations, whereas the O-glycosylation did not affect the TCB Mab biological activity. We established an online native CEC-UV-MS method, with an ammonium acetate buffer and pH gradient, to directly monitor the TCB Mab charge variants. All abundant chemical degradations and post-translational amino acid modifications already identified by offline fraction experiments and liquid chromatography mass spectrometry peptide mapping could also be monitored by the online CEC-UV-MS method. The herein reported online native CEC-UV-MS methodology represents a complementary or even alternative approach for multiattribute monitoring of biologics, offering multiple benefits, including increased throughput and reduced sample handling and intact protein information in the near-native state.
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Affiliation(s)
- Markus Haberger
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | | | - Michaela Hook
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Jürgen Fichtl
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Rainer Lang
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Florian Cymer
- Pharma Technical Development, F. Hoffmann-La Roche Ltd., c, 4070 Basel, Switzerland
| | - Mahdi Adibzadeh
- Pharma Technical Development, F. Hoffmann-La Roche Ltd., c, 4070 Basel, Switzerland
| | - Felix Kuhne
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Harald Wegele
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Dietmar Reusch
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Lea Bonnington
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
| | - Patrick Bulau
- Pharma Technical Development, Roche Diagnostics GmbH, 82377 Penzberg, Germany
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Lippold S, Büttner A, Choo MSF, Hook M, de Jong CJ, Nguyen-Khuong T, Haberger M, Reusch D, Wuhrer M, de Haan N. Cysteine Aminoethylation Enables the Site-Specific Glycosylation Analysis of Recombinant Human Erythropoietin using Trypsin. Anal Chem 2020; 92:9476-9481. [PMID: 32578997 DOI: 10.1021/acs.analchem.0c01794] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recombinant human erythropoietin (rhEPO) is an important biopharmaceutical for which glycosylation is a critical quality attribute. Therefore, robust analytical methods are needed for the in-depth characterization of rhEPO glycosylation. Currently, the protease GluC is widely established for the site-specific glycosylation analysis of rhEPO. However, this enzyme shows disadvantages, such as its specificity and the characteristics of the resulting (glyco)peptides. The use of trypsin, the gold standard protease in proteomics, as the sole protease for rhEPO is compromised, as no natural tryptic cleavage site is located between the glycosylation sites Asn24 and Asn38. Here, cysteine aminoethylation using 2-bromoethylamine was applied as an alternative alkylation strategy to introduce artificial tryptic cleavage sites at Cys29 and Cys33 in rhEPO. The (glyco)peptides resulting from a subsequent digestion using trypsin were analyzed by reverse-phase liquid chromatography-mass spectrometry. The new trypsin-based workflow was easily implemented by adapting the alkylation step in a conventional workflow and was directly compared to an established approach using GluC. The new method shows an improved specificity, a significantly reduced chromatogram complexity, allows for shorter analysis times, and simplifies data evaluation. Furthermore, the method allows for the monitoring of additional attributes, such as oxidation and deamidation at specific sites in parallel to the site-specific glycosylation analysis of rhEPO.
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Affiliation(s)
- Steffen Lippold
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Alexander Büttner
- Pharma Technical Development, Roche Diagnostics GmbH, Nonnenwald 2, 82377 Penzberg, Germany
| | - Matthew S F Choo
- Bioprocessing Technology Institute, Agency for Science Technology and Research, 20 Biopolis Way No. 06-01, Singapore 138668
| | - Michaela Hook
- Pharma Technical Development, Roche Diagnostics GmbH, Nonnenwald 2, 82377 Penzberg, Germany
| | - Coen J de Jong
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Terry Nguyen-Khuong
- Bioprocessing Technology Institute, Agency for Science Technology and Research, 20 Biopolis Way No. 06-01, Singapore 138668
| | - Markus Haberger
- Pharma Technical Development, Roche Diagnostics GmbH, Nonnenwald 2, 82377 Penzberg, Germany
| | - Dietmar Reusch
- Pharma Technical Development, Roche Diagnostics GmbH, Nonnenwald 2, 82377 Penzberg, Germany
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Noortje de Haan
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
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Falck D, Haberger M, Plomp R, Hook M, Bulau P, Wuhrer M, Reusch D. Affinity purification of erythropoietin from cell culture supernatant combined with MALDI-TOF-MS analysis of erythropoietin N-glycosylation. Sci Rep 2017; 7:5324. [PMID: 28706253 PMCID: PMC5509673 DOI: 10.1038/s41598-017-05641-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 06/01/2017] [Indexed: 12/18/2022] Open
Abstract
Erythropoietin (EPO) is a heavily glycosylated hormone whose recombinant forms are used for treatment of anaemia. EPO glycosylation is important for its pharmacological properties. An analytical workflow, which can determine EPO glycosylation in an accurate and high-throughput fashion from cell culture supernatant (CCS) in approximately 24 h, offers the possibility to follow changes during production. To address this challenge, we present a complete workflow consisting of protein purification, glycan release, sialic acid derivatization, solid phase extraction, matrix-assisted laser desorption/ionization - mass spectrometry (MALDI-MS) analysis and MassyTools data processing. EPO purification from CCS by anti-EPO antibody coupled Sepharose beads yielded excellent purity with acceptable recovery and was free of glycoform bias. Glycosylation profiles obtained by MALDI-MS were highly comparable to those obtained with an established capillary gel electrophoresis–laser induced fluorescence method. Our method delivers accurate results for the analysis of changes of important glycosylation parameters, such as sialylation and number of N-acetyllactosamine units, for the time course of a fermentation. We could resolve differences in glycosylation between several CCS samples.
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Affiliation(s)
- David Falck
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands.
| | - Markus Haberger
- Pharma Biotech Development Penzberg, Roche Diagnostics GmbH, 82377, Penzberg, Germany
| | - Rosina Plomp
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Michaela Hook
- Pharma Biotech Development Penzberg, Roche Diagnostics GmbH, 82377, Penzberg, Germany
| | - Patrick Bulau
- Pharma Biotech Development Penzberg, Roche Diagnostics GmbH, 82377, Penzberg, Germany
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Dietmar Reusch
- Pharma Biotech Development Penzberg, Roche Diagnostics GmbH, 82377, Penzberg, Germany
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9
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Reusch D, Haberger M, Falck D, Peter B, Maier B, Gassner J, Hook M, Wagner K, Bonnington L, Bulau P, Wuhrer M. Comparison of methods for the analysis of therapeutic immunoglobulin G Fc-glycosylation profiles-Part 2: Mass spectrometric methods. MAbs 2016; 7:732-42. [PMID: 25996192 PMCID: PMC4622708 DOI: 10.1080/19420862.2015.1045173] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [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] [Indexed: 11/16/2022] Open
Abstract
To monitor the Fc glycosylation of therapeutic immunoglobulin G in bioprocess development, product characterization and release analytics, reliable techniques for glycosylation analysis are needed. Several analytical methods are suitable for this application. We recently presented results comparing detection methods for glycan analysis that are separation-based, but did not include mass spectrometry (MS). In the study reported here, we comprehensively compared MS-based methods for Fc glycosylation profiling of an IgG biopharmaceutical. A therapeutic antibody reference material was analyzed 6-fold on 2 different days, and the methods investigated were compared with respect to precision, accuracy, throughput and analysis time. Emphasis was put on the detection and quantitation of sialic acid-containing glycans. Eleven MS methods were compared to hydrophilic interaction liquid chromatography of 2-aminobenzamide labeled glycans with fluorescence detection, which served as a reference method and was also used in the first part of the study. The methods compared include electrospray MS of the heavy chain and Fc part after limited digestion, liquid chromatography MS of a tryptic digest, porous graphitized carbon chromatography MS of released glycans, electrospray MS of glycopeptides, as well as matrix assisted laser desorption ionization MS of glycans and glycopeptides. Most methods showed excellent precision and accuracy. Some differences were observed with regard to the detection and quantitation of low abundant glycan species like the sialylated glycans and the amount of artefacts due to in-source decay.
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Key Words
- 2-AB, 2-aminobenzamide
- CE, capillary electrophoresis
- ESI-MS
- ESI-MS, electrospray ionization-mass spectrometry
- Fab, fragment antigen-binding
- Fc, fragment crystallizable
- HILIC-UHPLC, hydrophilic interaction liquid chromatography-ultra high performance liquid chromatography
- HILIC-UPLC
- HPAEC-PAD, high-performance anion exchange chromatography with pulsed amperometric detection
- IdeS protease, proteolytic enzyme like protease from Streptococcus pyrogenes
- IgG glycosylation
- IgG, immunoglobulin G
- LC-MS
- LCMS, liquid chromatography-mass spectrometry
- MALDI, matrix assisted laser desorption ionization
- MALDI-MS
- PGC-MS, porous graphitized carbon chromatography- mass spectrometry
- PNGase F, Peptide-N-Glycosidase F
- RP-HPLC, reversed phase high performance liquid chromatography
- TIC, total ion chromatogram
- glycan analysis
- mAb, monoclonal antibody
- mass spectrometry
- method comparison
- monoclonal antibody (mAb)
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Affiliation(s)
- Dietmar Reusch
- a Pharma Biotech Development Penzberg; Roche Diagnostics GmbH ; Penzberg , Germany
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Haberger M, Leiss M, Heidenreich AK, Pester O, Hafenmair G, Hook M, Bonnington L, Wegele H, Haindl M, Reusch D, Bulau P. Rapid characterization of biotherapeutic proteins by size-exclusion chromatography coupled to native mass spectrometry. MAbs 2015; 8:331-9. [PMID: 26655595 PMCID: PMC4966600 DOI: 10.1080/19420862.2015.1122150] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
High-molecular weight aggregates such as antibody dimers and other side products derived from incorrect light or heavy chain association typically represent critical product-related impurities for bispecific antibody formats. In this study, an approach employing ultra-pressure liquid chromatography size-exclusion separation combined with native electrospray ionization mass spectrometry for the simultaneous formation, identification and quantification of size variants in recombinant antibodies was developed. Samples exposed to storage and elevated temperature(s) enabled the identification of various bispecific antibody size variants. This test system hence allowed us to study the variants formed during formulation and bio-process development, and can thus be transferred to quality control units for routine in-process control and release analytics. In addition, native SEC-UV/MS not only facilitates the detailed analysis of low-abundant and non-covalent size variants during process characterization/validation studies, but is also essential for the SEC-UV method validation prior to admission to the market.
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Affiliation(s)
- Markus Haberger
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Michael Leiss
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Anna-Katharina Heidenreich
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Oxana Pester
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Georg Hafenmair
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Michaela Hook
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Lea Bonnington
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Harald Wegele
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Markus Haindl
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Dietmar Reusch
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
| | - Patrick Bulau
- a Pharma Technical Development Analytics, Roche Diagnostics GmbH, Nonnenwald 2 , 82377 Penzberg , Germany
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11
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Reusch D, Haberger M, Maier B, Maier M, Kloseck R, Zimmermann B, Hook M, Szabo Z, Tep S, Wegstein J, Alt N, Bulau P, Wuhrer M. Comparison of methods for the analysis of therapeutic immunoglobulin G Fc-glycosylation profiles--part 1: separation-based methods. MAbs 2015; 7:167-79. [PMID: 25524468 PMCID: PMC4623496 DOI: 10.4161/19420862.2014.986000] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [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] [Indexed: 01/06/2023] Open
Abstract
Immunoglobulin G (IgG) crystallizable fragment (Fc) glycosylation is crucial for antibody effector functions, such as antibody-dependent cell-mediated cytotoxicity, and for their pharmacokinetic and pharmacodynamics behavior. To monitor the Fc-glycosylation in bioprocess development, as well as product characterization and release analytics, reliable techniques for glycosylation analysis are needed. A wide range of analytical methods has found its way into these applications. In this study, a comprehensive comparison was performed of separation-based methods for Fc-glycosylation profiling of an IgG biopharmaceutical. A therapeutic antibody reference material was analyzed 6-fold on 2 different days, and the methods were compared for precision, accuracy, throughput and other features; special emphasis was placed on the detection of sialic acid-containing glycans. Seven, non-mass spectrometric methods were compared; the methods utilized liquid chromatography-based separation of fluorescent-labeled glycans, capillary electrophoresis-based separation of fluorescent-labeled glycans, or high-performance anion exchange chromatography with pulsed amperometric detection. Hydrophilic interaction liquid chromatography-ultra high performance liquid chromatography of 2-aminobenzamide (2-AB)-labeled glycans was used as a reference method. All of the methods showed excellent precision and accuracy; some differences were observed, particularly with regard to the detection and quantitation of minor glycan species, such as sialylated glycans.
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Key Words
- 2-AB labeling
- 2-AB, 2-aminobenzamide
- ANTS, 8-aminonaphthalene-1, 3, 6-trisulfonate
- APTS labeling
- APTS, 8-aminopyrene-1, 3, 6-trisulfonic acid
- CCGE, cartridge-based capillary gel electrophoresis
- CE-LIF
- CE-LIF, capillary electrophoresis-laser induced fluorescence
- CHO, Chinese hamster ovary
- DNA analyzer
- DSA-FACE, DNA-sequencer-aided fluorophore-assisted carbohydrate electrophoresis
- ESI-MS, electrospray ionization-mass spectrometry
- Fab, fragment, antigen-binding
- Fc, fragment crystallizable
- HILIC-UPLC
- HILIC-UPLC, hydrophilic interaction liquid chromatography-ultra high performance liquid chromatography
- HPAEC
- HPAEC-PAD, high-performance anion exchange chromatography with pulsed amperometric detection
- HPLC, high performance liquid chromatography
- HR, high resolution
- IAB, InstantAB labeling
- IgG glycosylation
- IgG, immunoglobulin G
- MALDI-MS, matrix-assisted laser desorption/ionization-mass spectrometry
- glycan analysis
- high-throughput
- mAb, monoclonal antibody
- method comparison
- monoclonal antibody (mAb)
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Affiliation(s)
- Dietmar Reusch
- a Pharma Biotech Development Penzberg; Roche Diagnostics GmbH ; Penzberg , Germany
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12
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Haberger M, Heidenreich AK, Schlothauer T, Hook M, Gassner J, Bomans K, Yegres M, Zwick A, Zimmermann B, Wegele H, Bonnington L, Reusch D, Bulau P. Functional assessment of antibody oxidation by native mass spectrometry. MAbs 2015; 7:891-900. [PMID: 26000623 PMCID: PMC4622615 DOI: 10.1080/19420862.2015.1052199] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Oxidation of methionine (Met) residues is one of several chemical degradation pathways for recombinant IgG1 antibodies. Studies using several methodologies have indicated that Met oxidation in the constant IgG1 domains affects in vitro interaction with human neonatal Fc (huFcRn) receptor, which is important for antibody half-life. Here, a completely new approach to investigating the effect of oxidative stress conditions has been applied. Quantitative ultra-performance liquid chromatography mass spectrometry (MS) peptide mapping, classical surface plasmon resonance and the recently developed FcRn column chromatography were combined with the new fast-growing approach of native MS as a near native state protein complex analysis in solution. Optimized mass spectrometric voltage and pressure conditions were applied to stabilize antibody/huFcRn receptor complexes in the gas phase for subsequent native MS experiments with oxidized IgG1 material. This approach demonstrated a linear correlation between quantitative native MS and IgG-FcRn functional analysis. In our study, oxidation of the heavy chain Met-265 resulted in a stepwise reduction of mAb3/huFcRn receptor complex formation. Remarkably, a quantitative effect of the heavy chain Met-265 oxidation on relative binding capacity was only detected for doubly oxidized IgG1, whereas IgG1 with only one oxidized heavy chain Met-265 was not found to significantly affect IgG1 binding to huFcRn. Thus, mono-oxidized IgG1 heavy chain Met-265 most likely does not represent a critical quality attribute for pharmacokinetics.
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Affiliation(s)
- Markus Haberger
- a Pharma Technical Development Penzberg; Roche Diagnostics GmbH ; Penzberg , Germany
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13
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Haberger M, Bomans K, Diepold K, Hook M, Gassner J, Schlothauer T, Zwick A, Spick C, Kepert JF, Hienz B, Wiedmann M, Beck H, Metzger P, Mølhøj M, Knoblich C, Grauschopf U, Reusch D, Bulau P. Assessment of chemical modifications of sites in the CDRs of recombinant antibodies: Susceptibility vs. functionality of critical quality attributes. MAbs 2014; 6:327-39. [PMID: 24441081 PMCID: PMC3984323 DOI: 10.4161/mabs.27876] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [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] [Indexed: 01/10/2023] Open
Abstract
Modifications like asparagine deamidation, aspartate isomerization, methionine oxidation, and lysine glycation are typical degradations for recombinant antibodies. For the identification and functional evaluation of antibody critical quality attributes (CQAs) derived from chemical modifications in the complementary-determining regions (CDRs) and the conserved regions, an approach employing specific stress conditions, elevated temperatures, pH, oxidizing agents, and forced glycation with glucose incubation, was applied. The application of the specific stress conditions combined with ion exchange chromatography, proteolytic peptide mapping, quantitative liquid chromatography mass spectrometry, and functional evaluation by surface plasmon resonance analysis was adequate to identify and functionally assess chemical modification sites in the CDRs of a recombinant IgG1. LC-Met-4, LC-Asn-30/31, LC-Asn-92, HC-Met-100c, and HC Lys-33 were identified as potential CQAs. However, none of the assessed degradation products led to a complete loss of functionality if only one light or heavy chain of the native antibody was affected.
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Affiliation(s)
- Markus Haberger
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Katrin Bomans
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Katharina Diepold
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Michaela Hook
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Jana Gassner
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Tilman Schlothauer
- Pharma Research and Early Development; Roche Diagnostics GmbH; Penzberg, Germany
| | - Adrian Zwick
- Pharma Research and Early Development; Roche Diagnostics GmbH; Penzberg, Germany
| | - Christian Spick
- Pharma Research and Early Development; Roche Diagnostics GmbH; Penzberg, Germany
| | - Jochen Felix Kepert
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Brigitte Hienz
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Michael Wiedmann
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Hermann Beck
- Pharma Technical Development Basel; F. Hoffmann-La Roche Ltd; Basel, Switzerland
| | - Philipp Metzger
- Pharma Technical Development Basel; F. Hoffmann-La Roche Ltd; Basel, Switzerland
| | - Michael Mølhøj
- Pharma Research and Early Development; Roche Diagnostics GmbH; Penzberg, Germany
| | - Constanze Knoblich
- Pharma Technical Development Basel; F. Hoffmann-La Roche Ltd; Basel, Switzerland
| | - Ulla Grauschopf
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Dietmar Reusch
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
| | - Patrick Bulau
- Pharma Technical Development Penzberg; Roche Diagnostics GmbH; Penzberg, Germany
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14
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Henry SP, Takanosu M, Boyd TC, Mayne PM, Eberspaecher H, Zhou W, de Crombrugghe B, Hook M, Mayne R. Expression pattern and gene characterization of asporin. a newly discovered member of the leucine-rich repeat protein family. J Biol Chem 2001; 276:12212-21. [PMID: 11152695 DOI: 10.1074/jbc.m011290200] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [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] [Indexed: 01/13/2023] Open
Abstract
We have discovered a new member of the class I small leucine-rich repeat proteoglycan (SLRP) family which is distinct from the other class I SLRPs since it possesses a unique stretch of aspartate residues at its N terminus. For this reason, we called the molecule asporin. The deduced amino acid sequence is about 50% identical (and 70% similar) to decorin and biglycan. However, asporin does not contain a serine/glycine dipeptide sequence required for the assembly of O-linked glycosaminoglycans and is probably not a proteoglycan. The tissue expression of asporin partially overlaps with the expression of decorin and biglycan. During mouse embryonic development, asporin mRNA expression was detected primarily in the skeleton and other specialized connective tissues; very little asporin message was detected in the major parenchymal organs. The mouse asporin gene structure is similar to that of biglycan and decorin with 8 exons. The asporin gene is localized to human chromosome 9q22-9q21.3 where asporin is part of a SLRP gene cluster that includes extracellular matrix protein 2, osteoadherin, and osteoglycin. Further analysis shows that, with the exception of biglycan, all known SLRP genes reside in three gene clusters.
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Affiliation(s)
- S P Henry
- Graduate School of Biomedical Sciences, University of Texas, Houston, Texas, 77030, USA
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15
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Wann ER, Gurusiddappa S, Hook M. The fibronectin-binding MSCRAMM FnbpA of Staphylococcus aureus is a bifunctional protein that also binds to fibrinogen. J Biol Chem 2000; 275:13863-71. [PMID: 10788510 DOI: 10.1074/jbc.275.18.13863] [Citation(s) in RCA: 202] [Impact Index Per Article: 8.4] [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] [Indexed: 02/01/2023] Open
Abstract
Staphylococcus aureus is an important pathogen capable of causing a wide spectrum of diseases in humans and animals. This bacterium expresses a variety of virulence factors that participate in the process of infection. These include MSCRAMMs (microbial surface components recognizing adhesive matrix molecules) that mediate the adherence of the bacteria to host extracellular matrix components, such as collagen, fibronectin (Fn), and fibrinogen (Fg). Two Fn-binding MSCRAMMs, FnbpA and FnbpB, have been previously identified. The Fn binding activity has been localized to the approximately 40-amino acid residue D repeats in the C-terminal part of these proteins. However, no biological activity has yet been attributed to the N-terminal A regions of these proteins. These regions exhibit substantial amino acid sequence identity to the A regions of other staphylococcal MSCRAMMs, including ClfA, ClfB, and SdrG (Fbe), all of which bind Fg. This raises the question of whether the Fn-binding MSCRAMMs can also bind specifically to Fg. In this report, we show that a recombinant form of the A region of FnbpA does specifically recognize Fg. We localize the binding site in Fg for recombinant FnbpA to the gamma-chain, in particular to the C-terminal residues of this polypeptide, the site also recognized by ClfA. In addition, we demonstrate that recombinant FnbpA can compete with ClfA for binding to both immobilized and soluble Fg. By the use of surface plasmon resonance spectroscopy and fluorescence polarization, we determine the dissociation equilibrium constant for the interaction of recombinant FnbpA with intact immobilized Fg and with a synthetic C-terminal gamma-chain peptide, respectively. Finally, by overexpressing FnbpA in a mutant strain of S. aureus that lacks the expression of both ClfA and ClfB, we show that native FnbpA can mediate the interaction of S. aureus with soluble Fg.
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Affiliation(s)
- E R Wann
- Center for Extracellular Matrix Biology, Department of Biochemistry and Biophysics, Institute of Biosciences and Technology, Texas A&M University System Health Science Center, Houston, Texas 77030-3303, USA.
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Abstract
The systems required to provide coordinated health care to the chronically ill within a managed care contract are complex. As an integrated health care delivery system assuming shared financial risk of enrollees in a Medicare + Choice contract, many care processes need to be created to meet the needs of the clients and administrators. Nursing case management and physician partnering are integral to the creation of the care model. The fiscal data demonstrated, for clients in this model, that there was an overall decrease in the inpatient length of stay, hospital days per thousand, and 30-day readmission rates.
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Affiliation(s)
- M Schifalacqua
- Care Management & Quality Improvement, Aurora Health Care, West Allis, Wisconsin, USA
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17
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Affiliation(s)
- TJ Foster
- Microbiology Dept, Moyne Institute of Preventive Medicine, Trinity College, Dublin 2, Ireland
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18
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Abstract
Bronchiolitis obliterans organizing pneumonia (BOOP) is rarely associated with dermatomyositis and may be resistant to conventional corticosteroid therapy under this circumstance. We present a case of BOOP associated with dermatomyositis that responded to a combination of cyclophosphamide and corticosteroid therapy after corticosteroid treatments, alone, had failed. We believe this case shows it is important to recognize that facial rash in the presence of respiratory distress may represent dermatomyositis with BOOP and aggressive treatment may be necessary for resolution of pulmonary symptoms.
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Affiliation(s)
- K A Knoell
- Department of Dermatology, University of Virginia, Charlottesville, USA.
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19
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Deere M, Johnson J, Garza S, Harrison WR, Yoon SJ, Elder FF, Kucherlapati R, Hook M, Hecht JT. Characterization of human DSPG3, a small dermatan sulfate proteoglycan. Genomics 1996; 38:399-404. [PMID: 8975717 DOI: 10.1006/geno.1996.0643] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [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] [Indexed: 02/03/2023]
Abstract
PG-Lb is a small dermatan sulfate proteoglycan that has been previously characterized in chicken. In the developing limb, chick PG-Lb appears to be exclusively expressed in the zone of flattened chondrocytes. We have cloned and sequenced the human homolog to chick PG-Lb from two human chondrocyte cDNA libraries and a human chondrocyte RNA sample. The human homolog has been named DSPG3, as it is the third member of the small dermatan sulfate proteoglycan family to be identified and characterized along with biglycan (PG-I) and decorin (PG-II). DSPG3 maps to chromosome 12q21 and is composed of 1515 nucleotides of cDNA that code for a 322-amino-acid protein. The protein contains three potential glycosaminoglycan attachment sites, two N-glycosylation sites, a poly- glutamic acid stretch, and six cysteines. By Northern analysis, we have demonstrated that DSPG3 is expressed in cartilage, as well as ligament and placental tissues.
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Affiliation(s)
- M Deere
- Graduate School of Biological Sciences, The University of Texas Medical School, Houston 77225, USA
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20
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Abstract
Competition for residency positions in dermatology is intense. Training programs in other disciplines have described significant misrepresentation among their applicants in claims of research and publication. An evaluation was made of the curricula vitae for the 138 applicants with completed applications for our 1994 residency match. Cited articles were placed in four categories: "published," "in print/in press," "submitted for publication," and "in preparation/in progress." We found significantly less misrepresentation than has been described in other specialty training programs. Simplification of the way in which applicants verify their bibliography may reduce erroneous citations and remove implications of willful misrepresentation of academic achievements.
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Affiliation(s)
- A S Boyd
- Department of Medicine, Dermatology, Vanderbilt University, Nashville, TN, USA
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Derrick M, Krakauer D, Magill S, Mikunas D, Musgrave B, Okrasinski JR, Repond J, Stanek R, Talaga RL, Zhang H, Mattingly MCK, Anselmo F, Antonioli P, Bari G, Basile M, Bellagamba L, Boscherini D, Bruni A, Bruni G, Bruni P, Romeo GC, Castellini G, Cifarelli L, Cindolo F, Contin A, Corradi M, Gialas I, Giusti P, Iacobucci G, Laurenti G, Levi G, Margotti A, Massam T, Nania R, Palmonari F, Pesci A, Polini A, Sartorelli G, Garcia YZ, Zichichi A, Amelung C, Bornheim A, Crittenden J, Deffner R, Doeker T, Eckert M, Feld L, Frey A, Geerts M, Grothe M, Hartmann H, Heinloth K, Heinz L, Hilger E, Jakob HP, Katz UF, Mengel S, Paul E, Pfeiffer M, Rembser C, Schramm D, Stamm J, Wedemeyer R, Campbell-Robson S, Cassidy A, Cottingham WN, Dyce N, Foster B, George S, Hayes ME, Heath GP, Heath HF, Piccioni D, Roff DG, Tapper RJ, Yoshida R, Arneodo M, Ayad R, Capua M, Garfagnini A, Iannotti L, Schioppa M, Susinno G, Caldwell A, Cartiglia N, Jing Z, Liu W, Parsons JA, Ritz S, Sciulli F, Straub PB, Wai L, Yang S, Zhu Q, Borzemski P, Chwastowski J, Eskreys A, Jakubowski Z, Przybycień MB, Zachara M, Zawiejski L, Adamczyk L, Bednarek B, Jeleń K, Kisielewska D, Kowalski T, Przybycien M, Rulikowska-Zarębska E, Suszycki L, Zając J, Duliński Z, Kotański A, Abbiendi G, Bauerdick LAT, Behrens U, Beier H, Bienlein JK, Cases G, Deppe O, Desler K, Drews G, Flasiński M, Gilkinson DJ, Glasman C, Göttlicher P, Große-Knetter J, Haas T, Hain W, Hasell D, Heßling H, Iga Y, Johnson KF, Joos P, Kasemann M, Klanner R, Koch W, Kötz U, Kowalski H, Labs J, Ladage A, Löhr B, Löwe M, Lüke D, Mainusch J, Mańczak O, Milewski J, Monteiro T, Ng JST, Notz D, Ohrenberg K, Piotrzkowski K, Roco M, Rohde M, Roldán J, Schneekloth U, Schulz W, Selonke F, Surrow B, Tassi E, Voß T, Westphal D, Wolf G, Wollmer U, Youngman C, Zeuner W, Grabosch HJ, Kharchilava A, Mari SM, Meyer A, Schlenstedt S, Wulff N, Barbagli G, Gallo E, Pelfer P, Maccarrone G, Pasquale S, Votano L, Bamberger A, Eisenhardt S, Trefzger T, Wölfle S, Bromley JT, Brook NH, Bussey PJ, Doyle AT, Saxon DH, Sinclair LE, Utley ML, Wilson AS, Dannemann A, Holm U, Horstmann D, Sinkus R, Wick K, Burow BD, Hagge L, Lohrmann E, Poelz G, Schott W, Zetsche F, Bacon TC, Brümmer N, Butterworth I, Harris VL, Howell G, Hung BHY, Lamberti L, Long KR, Miller DB, Pavel N, Prinias A, Sedgbeer JK, Sideris D, Whitfield AF, Mallik U, Wang MZ, Wang SM, Wu JT, Cloth P, Filges D, An SH, Cho GH, Ko BJ, Lee SB, Nam SW, Park HS, Park SK, Kartik S, Kim HJ, McNeil RR, Metcalf W, Nadendla VK, Barreiro F, Fernandez JP, Graciani R, Hernández JM, Hervás L, Labarga L, Martinez M, Peso J, Puga J, Terron J, Trocóniz JF, Corriveau F, Hanna DS, Hartmann J, Hung LW, Lim JN, Matthews CG, Patel PM, Riveline M, Stairs DG, St-Laurent M, Ullmann R, Zacek G, Tsurugai T, Bashkirov V, Dolgoshein BA, Stifutkin A, Bashindzhagyan GL, Ermolov PF, Gladilin LK, Golubkov YA, Kobrin VD, Korzhavina IA, Kuzmin VA, Lukina OY, Proskuryakov AS, Savin AA, Shcheglova LM, Solomin AN, Zotov NP, Botje M, Chlebana F, Engelen J, Kamps M, Kooijman P, Kruse A, Sighem A, Tiecke H, Verkerke W, Vossebeld J, Vreeswijk M, Wiggers L, Wolf E, Woudenberg R, Acosta D, Bylsma B, Durkin LS, Gilmore J, Li C, Ling TY, Nylander P, Park IH, Romanowski TA, Bailey DS, Cashmore RJ, Cooper-Sarkar AM, Devenish RCE, Harnew N, Lancaster M, Lindemann L, McFall JD, Nath C, Noyes VA, Quadt A, Tickner JR, Uijterwaal H, Walczak R, Waters DS, Wilson FF, Yip T, Bertolin A, Brugnera R, Carlin R, Corso F, Giorgi M, Dosselli U, Limentani S, Morandin M, Posocco M, Stanco L, Stroili R, Voci C, Zuin F, Bulmahn J, Feild RG, Oh BY, Whitmore JJ, D’Agostini G, Marini G, Nigro A, Hart JC, McCubbin NA, Shah TP, Barberis E, Dubbs T, Heusch C, Hook M, Lockman W, Rahn JT, Sadrozinski HFW, Seiden A, Williams DC, Biltzinger J, Seifert RJ, Schwarzer O, Walenta AH, Zech G, Abramowicz H, Briskin G, Dagan S, Levy A, Fleck JI, Inuzuka M, Ishii T, Kuze M, Mine S, Nakao M, Suzuki I, Tokushuku K, Umemori K, Yamada S, Yamazaki Y, Chiba M, Hamatsu R, Hirose T, Homma K, Kitamura S, Matsushita T, Yamauchi K, Cirio R, Costa M, Ferrero MI, Maselli S, Peroni C, Sacchi R, Solano A, Staiano A, Dardo M, Bailey DC, Benard F, Brkic M, Fagerstroem CP, Hartner GF, Joo KK, Levman GM, Martin JF, Orr RS, Polenz S, Sampson CR, Simmons D, Teuscher RJ, Butterworth JM, Catterall CD, Jones TW, Kaziewicz PB, Lane JB, Saunders RL, Shulman J, Sutton MR, Lu B, Mo LW, Bogusz W, Ciborowski J, Gajewski J, Grzelak G, Kasprzak M, Krzyżanowski M, Muchorowski K, Nowak RJ, Pawlak JM, Tymieniecka T, Wróblewski AK, Zakrzewski JA, Żarnecki AF, Adamus M, Coldewey C, Eisenberg Y, Hochman D, Karshon U, Revel D, Zer-Zion D, Badgett WF, Breitweg J, Chapin D, Cross R, Dasu S, Foudas C, Loveless RJ, Mattingly S, Reeder DD, Silverstein S, Smith WH, Vaiciulis A, Wodarczyk M, Bhadra S, Cardy ML, Frisken WR, Khakzad M, Murray WN, Schmidke WB. Measurement of theF 2 structure function in deep inelastice + p scattering using 1994 data from the ZEUS detector at HERA. ACTA ACUST UNITED AC 1996. [DOI: 10.1007/s002880050260] [Citation(s) in RCA: 132] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Prasthofer T, Ek B, Ekman P, Owens R, Hook M, Johansson S. Protein kinase C phosphorylates two of the four known syndecan cytoplasmic domains in vitro. Biochem Mol Biol Int 1995; 36:793-802. [PMID: 8528141] [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] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The transmembrane heparan sulfate proteoglycans of the syndecan family are implicated to participate in several cellular reactions which are dependent on protein kinase C. We have used an in vitro assay to assess whether any of the Peptides corresponding to the complete cytoplasmic domains of rat syndecans 1 through 4 were used as substrates for the enzyme. The syndecan-2 (fibroglycan) and syndecan-3 (N-syndecan) peptides were both found to be phosphorylated by protein kinase C with Kms of 15 +/- 3 microM and 85 +/- 25 microM, respectively, while the syndecan-1 and -4 peptides were not phosphorylated under the conditions used. The sites of in vitro phosphorylation for syndecans-2 and -3 were localized to ser-197 and ser-339, respectively. Thus, among 13 available sites (serines and threonines) in the four peptides, two were selectively modified by the enzyme. The specificity and the kinetics of the reactions indicate that the cytoplasmic domains of syndecan-2 and -3 are likely to be physiological substrates for protein kinase C.
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Affiliation(s)
- T Prasthofer
- Department of Medical and Physiological Chemistry, University of Uppsala, Sweden
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23
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Bidanset DJ, LeBaron R, Rosenberg L, Murphy-Ullrich JE, Hook M. Regulation of cell substrate adhesion: effects of small galactosaminoglycan-containing proteoglycans. J Cell Biol 1992; 118:1523-31. [PMID: 1522122 PMCID: PMC2289618 DOI: 10.1083/jcb.118.6.1523] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Cell adhesion is a process which is initiated by the attachment of cells to specific sites in adhesive matrix proteins via cell surface receptors of the integrin family. This is followed by a reorganization of cytoskeletal elements which results in cell spreading and the formation of focal adhesion plaques. We have examined the effects of a class of small galactosaminoglycan-containing proteoglycans on the various stages of cell adhesion to fibronectin-coated substrates. Our results indicate that dermatan sulfate proteoglycans (DSPGs) derived from cartilage, as well as other related small proteoglycans, inhibit the initial attachment of CHO cells and rat embryo fibroblasts to substrates composed of the 105-kD cell-binding fibronectin fragment, but do not affect cell attachment to intact fibronectin. Although this effect involves binding of DSPGs to the substrate via the protein core, the intact proteoglycan is necessary for the observed activity. Isolated core proteins are inactive. The structural composition of the galactosaminoglycan chain does not appear to be functionally significant since both chondroitin sulfate and various dermatan sulfate proteoglycans of this family inhibit cell attachment to the fibronectin fragment. Neither the percentage of cells spread nor the mean area of spread cells adhering to substrates of intact fibronectin was significantly affected by the DSPGs. However, significantly fewer cells formed focal adhesions in the presence of DSPGs as compared with untreated control cells. These results suggest that the binding of small galactosaminoglycan-containing proteoglycans to a fibronectin substrate may affect several stages in the cell adhesion process.
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Affiliation(s)
- D J Bidanset
- Department of Cell Biology, University of Alabama at Birmingham 35294
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24
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Guidry C, McFarland RJ, Morris R, Witherspoon CD, Hook M. Collagen gel contraction by cells associated with proliferative vitreoretinopathy. Invest Ophthalmol Vis Sci 1992; 33:2429-35. [PMID: 1634340] [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: 12/28/2022] Open
Abstract
The capacities of porcine choroidal fibroblasts, retinal glial cells, and retinal pigment epithelial cells to contract collagen gels in vitro were compared. Experiments with varied cell numbers indicated that glial cells are the most effective, followed by choroidal fibroblasts and retinal pigment epithelial cells. Analysis of the secretory products from cultures of these cell types revealed that retinal pigment epithelial cells synthesize and secrete peptides that promote fibroblast contraction of collagen gels in vitro. The mechanism of action of the retinal pigment epithelial cell-secreted contraction promoter was compared with that found in serum (type A) and secreted by cultured endothelial cells (type B). Like the serum factor, the retinal pigment epithelial cell-secreted factor was not dependent on active protein synthesis by the target cell and must be present continuously to promote contraction.
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Affiliation(s)
- C Guidry
- Department of Biochemistry, University of Alabama, Birmingham 35294
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25
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Hardwick C, Hoare K, Owens R, Hohn HP, Hook M, Moore D, Cripps V, Austen L, Nance DM, Turley EA. Molecular cloning of a novel hyaluronan receptor that mediates tumor cell motility. J Cell Biol 1992; 117:1343-50. [PMID: 1376732 PMCID: PMC2289508 DOI: 10.1083/jcb.117.6.1343] [Citation(s) in RCA: 286] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A cDNA encoding a unique hyaluronan receptor has been molecularly cloned from a lambda GT11 3T3 cDNA expression library. Immunoblot analyses of cell lysates, using antibodies to peptides encoded in the cDNA, specifically react with a 58-kD protein. This protein is regulated by the mutant H-ras gene in cells containing a metallothionein promoter H-ras hybrid gene. Further, antibodies to peptide sequences encoded in the cDNA block the increase in locomotion resulting from induction of the mutant H-ras gene in this cell line. In a transblot assay, the bacterially expressed protein binds to biotinylated hyaluronan. Antibodies to peptides encoded in the cDNA react in immunoblot assays with the 58- and 52-kD proteins of a novel hyaluronan receptor complex previously implicated in cell locomotion. Furthermore, antibodies specific to the 58- and 52-kD proteins, which block ras-induced locomotion, also cross-react with the expressed, encoded protein. The gene product described here appears to be a new type of hyaluronan receptor that is involved in cell locomotion. It is named RHAMM, an acronym for receptor for hyaluronan-mediated motility.
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Affiliation(s)
- C Hardwick
- Department of Biochemistry, University of Alabama, Birmingham 35233
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26
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Bidanset DJ, Guidry C, Rosenberg LC, Choi HU, Timpl R, Hook M. Binding of the proteoglycan decorin to collagen type VI. J Biol Chem 1992; 267:5250-6. [PMID: 1544908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We have examined the interactions between the small dermatan sulfate proteoglycan decorin and collagen types I-VI using solid phase binding assays. The results of these studies showed that 125I-decorin bound most efficiently to collagen type VI in a time- and concentration-dependent manner. Furthermore, this interaction was specific and of moderately high affinity (Kd approximately 3 x 10(-7) M). Binding of decorin to collagen type VI appears to involve the decorin core protein rather than the glycosaminoglycan side chains, since the isolated core protein as well as a recombinant fusion protein containing a major segment (65%) of the human decorin core protein inhibited binding of 125I-decorin to collagen type VI. Other related proteoglycans and their respective core proteins also inhibited the binding of 125I-decorin to collagen type VI, whereas unrelated proteins and isolated glycosaminoglycan chains were without effect. In addition to decorin, collagen type II was also shown to bind to immobilized collagen type VI. Both interactions were effectively inhibited by preincubation of the immobilized collagen VI with decorin or collagen type II. These results suggested that the collagen type VI molecule has binding sites for collagen type II and decorin which are located in close proximity on the collagen type VI molecule. Possible functional roles of these interactions are discussed.
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Affiliation(s)
- D J Bidanset
- Department of Cell Biology, University of Alabama, Birmingham 35294
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Abstract
Endothelial 1 (E1) is identified as an endothelial cell secreted factor that stimulates collagen gel contraction by fibroblasts. This identification is based on (a) co-localization of stimulatory activity in endothelial cell conditioned media with synthetic E1 in reversed phase analysis; (b) removal of the activity from conditioned media with antiserum directed against E1; and (c) the activity of synthetic E1. Treatment of endothelial cell conditioned media with immobilized anti-E1 antibodies removed 59% of the activity from the pool suggesting that E1 is the major contraction promoter in endothelial cell conditioned medium. The mechanism of action of E1 is shown to be different from serum in that E1-promoted contraction is dependent upon the synthesis of an unknown effector protein. Synthetic E1 is shown to be a potent promoter of gel contraction with half-maximal activity occurring at 32 pM. Two other endothelins, E2 and VIC, are slightly less active than E1. A fourth endothelin species, E3, is substantially less active. A comparison of E1 with other contraction promoting peptides revealed that E1 and platelet-derived growth factor are essentially equal in specific activity, whereas TGF beta is approximately 50-fold more potent.
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Affiliation(s)
- C Guidry
- Department of Biochemistry, University of Alabama, Birmingham 35294
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29
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Lantz MS, Allen RD, Duck LW, Blume JL, Switalski LM, Hook M. Identification of Porphyromonas gingivalis components that mediate its interactions with fibronectin. J Bacteriol 1991; 173:4263-70. [PMID: 1829726 PMCID: PMC208085 DOI: 10.1128/jb.173.14.4263-4270.1991] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [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] [Indexed: 12/29/2022] Open
Abstract
Porphyromonas (Bacteroides) gingivalis W12 binds and degrades human plasma fibronectin. In the presence of the protease inhibitor N-alpha-p-tosyl-L-lysyl chloromethyl ketone, P. gingivalis cells accumulated substantial amounts of 125I-fibronectin as a function of incubation time. Fibronectin binding was specific, reversible, and saturable. The Kd for the reaction was estimated to be on the order of 100 nM, and there was an average of 3.5 x 10(3) fibronectin binding sites per cell. Unlabeled fibronectin inhibited the binding of 125I-fibronectin to bacteria; however, fibrinogen was an even more efficient inhibitor of 125I-fibronectin binding. Unrelated proteins were without effect on fibronectin binding. A fibronectin-binding component (Mr, 150,000) was identified in sodium dodecyl sulfate-solubilized P. gingivalis. Fibronectin was degraded into discrete peptides by P. gingivalis W12. The degradation of fibronectin was inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone. Two P. gingivalis components (Mrs, 120,000 and 150,000) degraded fibronectin in substrate-containing gels following sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In a previous study (M. S. Lantz, R. D. Allen, T. A. Vail, L. M. Switalski, and M. Hook, J. Bacteriol. 173:495-504, 1991), we found that the same strain of P. gingivalis bound and subsequently degraded human fibrinogen via apparently distinct cell surface components of molecular sizes similar to those of components now implicated in the binding and degradation of fibronectin. These results raise the possibility that the two ligands are recognized and modified by the same components on P. gingivalis W12. In support of this hypothesis, unlabeled fibrinogen effectively inhibited the binding of 125I-fibronectin to bacteria and blocked 125I-fibronectin binding to a P. gingivalis ligand-binding component (Mr, 150,000 immobilized on a nitrocellulose membrane.
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Affiliation(s)
- M S Lantz
- Department of Periodontics, University of Alabama, Birmingham 35294
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30
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Affiliation(s)
- M S Lantz
- Department of Periodontics, University of Alabama, Birmingham
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31
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Hook M, McGavin MJ, Switalski LM, Raja R, Raucci G, Lindgren PE, Lindberg M, Signas C. Interactions of bacteria with extracellular matrix proteins. Cell Differ Dev 1990; 32:433-8. [PMID: 1965958 DOI: 10.1016/0922-3371(90)90060-a] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- M Hook
- Dept. of Biochemistry, University of Alabama, Birmingham 35294
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32
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Guidry C, Miller EJ, Hook M. A second fibronectin-binding region is present in collagen alpha chains. J Biol Chem 1990; 265:19230-6. [PMID: 2229073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The interactions of plasma fibronectin with alpha chains or cyanogen bromide fragments of collagen types I and II have been studied using a variety of techniques. Affinity chromatography of cyanogen bromide-cleaved type II collagen on immobilized fibronectin revealed the binding of cyanogen bromide fragment CB12 in addition to the previously characterized CB10. Using fluorescence polarization, we analyzed the interaction between the collagen peptides and fluorescein isothiocyanate-labeled 42-kDa gelatin-binding fragment of fibronectin in solution. Dissociation constants for the binding of CB10 and CB12 to the fibronectin fragment were calculated as 0.38 and 0.94 microM, respectively, indicating a lower affinity for the uncharacterized site. However, as with CB10, CB12 was able to compete effectively with the intact alpha chain for bindinng to fibronectin. Additionally, both CB10 and CB12 absorbed to tissue culture surfaces were each able to support fibronectin-dependent cell adhesion. Finally, the regions of alpha 2(I) homologous to CB12 and CB10 were found to be active in fibronectin binding, demonstrating the presence of two fibronectin-binding regions in this collagen chain.
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Affiliation(s)
- C Guidry
- Department of Biochemistry, University of Alabama, Birmingham 35294
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Abstract
Binding of cells of Staphylococcus aureus to fibronectin has been proposed as a mechanism of bacterial adhesion to host tissues. In this study, we have attempted to define the role of a recently identified fibronectin receptor in the adhesion of staphylococcal cells to fibronectin-containing substrates by using different receptor analogs as potential inhibitors of bacterial adherence. The results showed that synthetic peptides D1, D2, and D3, corresponding to variations of a repeated unit in the fibronectin-binding domain of the receptor, and ZZ-FR, a chimeric protein containing the fibronectin-binding domain of the receptor with the D1, D2, and D3 sequences, inhibited the attachment of staphylococcal cells to microtiter wells coated with intact fibronectin or with the 29-kilodalton amino-terminal fragment of fibronectin. The chimeric protein ZZ-FR also partially inhibited the adherence of staphylococci to human plasma clots formed in vitro but had no effect on bacterial adhesion to clots formed from fibronectin-depleted plasma. These data confirm previous reports suggesting that fibronectin may serve as a substrate for adhesion of staphylococcal cells and indicate that bacterial adhesion is mediated by the identified fibronectin receptor. Furthermore, analogs to the fibronectin receptor can be used to inhibit the adhesion of bacterial cells to these model substrates, and these analogs may be of clinical use.
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Affiliation(s)
- R H Raja
- Department of Biochemistry, University of Alabama, Birmingham 35294
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Richardt G, Haass M, Hook M, Neeb S, Schömig A. Nicotine-induced noradrenaline and neuropeptide Y release in normoxic and anoxic guinea pig heart. J Mol Cell Cardiol 1990. [DOI: 10.1016/0022-2828(90)91569-s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Bovine aortic endothelial cells (BAEC), grown in vitro, are shown to synthesize and secrete factor(s) that stimulate fibroblasts to contract collagen matrices. The amount of contraction-promoting activity in the conditioned media is dependent on conditioning time and the number of cells in the culture. Production of the contraction-promoting activity continues at a high stable level for at least 5 d in serum-free medium but is abolished when the cells are exposed to an inhibitor of protein synthesis. The mechanism of action of the contraction factor(s) derived from endothelial cells was compared with that of unidentified serum factors. The endothelial cell-secreted factor(s) depends on active protein synthesis by the target cell but does not need to be present during the contraction process. The serum factors on the other hand promote collagen contraction in the absence of de novo protein synthesis but need to be continuously present. Preliminary biochemical characterization of the contraction-promoting factors produced by endothelial cells revealed properties similar to those of previously identified growth factors. However, the BAEC-secreted factor was found to be distinct from a previously identified contraction-promoting transforming growth factor beta.
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Affiliation(s)
- C Guidry
- Department of Biochemistry, University of Alabama, Birmingham 35294
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37
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Hook M, Guevarra J, Pierce MK, Scott-Sorenson N. Critical care voices: including sexual counseling in clinical practice. Dimens Crit Care Nurs 1989; 8:375. [PMID: 2625078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We asked four practicing critical care nurses for tips on how they include sexual counseling in their practice with MI patients and families. Each one has developed a different, but effective, approach.
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Abstract
Ultrastructural studies of the cartilaginous articular surfaces of human and rabbit joints have shown that cartilage is the target substratum for adhesion by Staphylococcus aureus, leading to intra-articular sepsis. Transmission and scanning electron microscope studies demonstrated bacteria in intimate contact with acellular cartilage matrix surfaces, particularly with collagen fibres. Certain strains of Staphylococcus aureus used in these experiments reveal a high binding capacity to collagen that is derived from a cartilage matrix. These studies indicate that the pathogenesis of intra-articular sepsis is based on the ability of certain strains of staphylococci to bind preferentially to a cartilage matrix.
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Affiliation(s)
- A Voytek
- Section of Orthopedic Surgery, Wake Forest University Medical Center, Winston-Salem, NC 27103
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Abstract
Analyses by anion exchange chromatography indicate that heparan sulfate proteoglycans isolated from the livers of experimentally diabetic rats have a reduced net negative charge as compared with heparan sulfate proteoglycans from control rats. In contrast, the size of the normal and diabetic proteoglycans are indistinguishable as are the size of individual polysaccharide chains when compared by gel chromatography. The reduced net negative charge of heparin sulfate from diabetic rats is shown to be caused by a reduced number of sulfate groups present in the diabetic heparan sulfate. Results are presented suggesting that one of the biosynthetic enzymes; the N-deacelylase, which tentatively has been identified as a regulatory enzyme affecting the sulfate content of the polysaccharide chains, may be inhibited in the diabetic rat.
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