22 results on '"Shpacovitch V"'
Search Results
2. Protease-activated receptors: novel PARtners in innate immunity
- Author
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Shpacovitch, V., Feld, M., Bunnett, N.W., and Steinhoff, M.
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- 2007
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3. Agonists of Proteinase-Activated Receptor-2 (PAR2) Enhance Lipopolysaccharide-Induced Effects on Human Neutrophil Functions In Vitro
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Shpacovitch, V, Seeliger, S, Huber-Lang, M, Balkow, S, Feld, M, Varga, G, Steinhoff, M, and Luger, T
- Published
- 2006
4. Role of protease-activated receptors in inflammatory responses, innate and adaptive immunity
- Author
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Shpacovitch, V, primary, Feld, M, additional, Hollenberg, M D, additional, Luger, T A, additional, and Steinhoff, M, additional
- Published
- 2008
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5. Agonists of proteinase-activated receptor-2 modulate human neutrophil cytokine secretion, expression of cell adhesion molecules, and migration within 3-D collagen lattices
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Shpacovitch, V M, primary, Varga, G, additional, Strey, A, additional, Gunzer, M, additional, Mooren, F, additional, Buddenkotte, J, additional, Vergnolle, N, additional, Sommerhoff, C P, additional, Grabbe, S, additional, Gerke, V, additional, Homey, B, additional, Hollenberg, M, additional, Luger, T A, additional, and Steinhoff, M, additional
- Published
- 2004
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- View/download PDF
6. Y-box protein-1/p18 fragment identifies malignancies in patients with chronic liver disease
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Shpacovitch Victoria, Eberhardt Christiane S, Kaehne Thilo, En-Nia Abdelaziz, Kanig Nicolas, Tacke Frank, Trautwein Christian, and Mertens Peter R
- Subjects
cold shock proteins ,liver transplantation ,hepatocellular carcinoma ,cancer screening ,serum markers ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Immunohistochemical detection of cold shock proteins is predictive for deleterious outcome in various malignant diseases. We recently described active secretion of a family member, denoted Y-box (YB) protein-1. We tested the clinical and diagnostic value of YB-1 protein fragment p18 (YB-1/p18) detection in blood for malignant diseases. Methods We used a novel monoclonal anti-YB-1 antibody to detect YB-1/p18 by immunoblotting in plasma samples of healthy volunteers (n = 33), patients with non-cancerous, mostly inflammatory diseases (n = 60), hepatocellular carcinoma (HCC; n = 25) and advanced solid tumors (n = 20). YB-1/p18 was then tested in 111 patients with chronic liver diseases, alongside established tumor markers and various diagnostic measures, during evaluation for potential liver transplantation. Results We developed a novel immunoblot to detect the 18 kD fragment of secreted YB-1 in human plasma (YB-1/p18) that contains the cold-shock domains (CSD) 1-3 of the full-length protein. YB-1/p18 was detected in 11/25 HCC and 16/20 advanced carcinomas compared to 0/33 healthy volunteers and 10/60 patients with non-cancerous diseases. In 111 patients with chronic liver disease, YB-1/p18 was detected in 20 samples. Its occurrence was not associated with advanced Child stages of liver cirrhosis or liver function. In this cohort, YB-1/p18 was not a good marker for HCC, but proved most powerful in detecting malignancies other than HCC (60% positive) with a lower rate of false-positive results compared to established tumor markers. Alpha-fetoprotein (AFP) was most sensitive in detecting HCC, but simultaneous assessment of AFP, CA19-9 and YB-1/p18 improved overall identification of HCC patients. Conclusions Plasma YB-1/p18 can identify patients with malignancies, independent of acute inflammation, renal impairment or liver dysfunction. The detection of YB-1/p18 in human plasma may have potential as a tumor marker for screening of high-risk populations, e.g. before organ transplantation, and should therefore be evaluated in larger prospective studies.
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- 2011
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7. Switchable Polyacrylic Acid Polyelectrolyte Brushes for Surface Plasmon Resonance Applications.
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Al-Bataineh QM, Telfah AD, Shpacovitch V, Tavares CJ, and Hergenröder R
- Abstract
Imaging wide-field surface plasmon resonance (SPR) microscopy sensors based on polyacrylic acid polyelectrolyte brushes (PAA PEBs) were designed to enhance the sensitivity of nano-object detection. The switching behavior of the PAA PEBs against changes in the pH values was investigated by analyzing the chemical, morphological, optical, and electrical properties. At pH ~1, the brushes collapse on the surface with the dominance of carboxylic groups (COOH). Upon the increase in the pH to nine, the switching process completes, and the brushes swell from dissociating most of the COOH groups and converting them into COO- groups. The domination of the negatively charged COO- groups increases the electrostatic repulsion in the polymer chains and stretches the brushes. The sensitivity of the SPR sensing device was investigated using a theoretical approach, as well as experimental measurements. The signal-to-noise ratio for a Au layer increases from six to eighteen after coating with PAA PEBs. In addition, the linewidth of the recorded image decreases from six pixels to five pixels by using the Au-PAA layers, which results from the enhanced spatial resolution of the recorded images. Coating a Au-layer with PAA PEBs enhances the sensitivity of the SPR sensing device, and improves the spatial resolution of the recorded image.
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- 2023
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8. The Employment of the Surface Plasmon Resonance (SPR) Microscopy Sensor for the Detection of Individual Extracellular Vesicles and Non-Biological Nanoparticles.
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Sharar N, Wüstefeld K, Talukder RM, Skolnik J, Kaufmann K, Giebel B, Börger V, Nolte F, Watzl C, Weichert F, Hergenröder R, and Shpacovitch V
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- Surface Plasmon Resonance methods, Microscopy, Silicon Dioxide, Gold, Employment, Nanoparticles chemistry, Extracellular Vesicles
- Abstract
A wide-field surface plasmon resonance (SPR) microscopy sensor employs the surface plasmon resonance phenomenon to detect individual biological and non-biological nanoparticles. This sensor enables the detection, sizing, and quantification of biological nanoparticles (bioNPs), such as extracellular vesicles (EVs), viruses, and virus-like particles. The selectivity of bioNP detection does not require biological particle labeling, and it is achieved via the functionalization of the gold sensor surface by target-bioNP-specific antibodies. In the current work, we demonstrate the ability of SPR microscopy sensors to detect, simultaneously, silica NPs that differ by four times in size. Employed silica particles are close in their refractive index to bioNPs. The literature reports the ability of SPR microscopy sensors to detect the binding of lymphocytes (around 10 μm objects) to the sensor surface. Taken together, our findings and the results reported in the literature indicate the power of SPR microscopy sensors to detect bioNPs that differ by at least two orders in size. Modifications of the optical sensor scheme, such as mounting a concave lens, help to achieve homogeneous illumination of a gold sensor chip surface. In the current work, we also characterize the improved magnification factor of the modified SPR instrument. We evaluate the effectiveness of the modified and the primary version of the SPR microscopy sensors in detecting EVs isolated via different approaches. In addition, we demonstrate the possibility of employing translation and rotation stepper motors for precise adjustments of the positions of sensor optical elements-prism and objective-in the primary version of the SPR microscopy sensor instrument, and we present an algorithm to establish effective sensor-actuator coupling.
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- 2023
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9. Surface Plasmon Resonance Sensitivity Enhancement Based on Protonated Polyaniline Films Doped by Aluminum Nitrate.
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Al-Bataineh QM, Shpacovitch V, Sadiq D, Telfah A, and Hergenröder R
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- Aluminum Compounds, Hydrochloric Acid chemistry, Surface Plasmon Resonance, Aniline Compounds chemistry
- Abstract
Complex composite films based on polyaniline (PANI) doped hydrochloric acid (HCl) incorporated with aluminum nitrate (Al(NO
3 )3 ) on Au-layer were designed and synthesized as a surface plasmon resonance (SPR) sensing device. The physicochemical properties of (PANI-HCl)/Al(NO3 )3 complex composite films were studied for various Al(NO3 )3 concentrations (0, 2, 4, 8, 16, and 32 wt.%). The refractive index of the (PANI-HCl)/Al(NO3 )3 complex composite films increased continuously as Al(NO3 )3 concentrations increased. The electrical conductivity values increased from 5.10 µS/cm to 10.00 µS/cm as Al(NO3 )3 concentration increased to 32 wt.%. The sensitivity of the SPR sensing device was investigated using a theoretical approach and experimental measurements. The theoretical system of SPR measurement confirmed that increasing Al(NO3 )3 in (PANI-HCl)/Al(NO3 )3 complex composite films enhanced the sensitivity from about 114.5 [Deg/RIU] for Au-layer to 159.0 [Deg/RIU] for Au-((PANI-HCl)/Al(NO3 )3 (32 wt.%)). In addition, the signal-to-noise ratio for Au-layer was 3.95, which increased after coating by (PANI-HCl)/Al(NO3 )3 (32 wt.%) complex composite layer to 8.82. Finally, we conclude that coating Au-layer by (PANI-HCl)/Al(NO3 )3 complex composite films enhances the sensitivity of the SPR sensing device.- Published
- 2022
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10. Features of Sizing and Enumeration of Silica and Polystyrene Nanoparticles by Nanoparticle Tracking Analysis (NTA).
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Usfoor Z, Kaufmann K, Rakib ASH, Hergenröder R, and Shpacovitch V
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Nanoparticle Tracking Analysis (NTA) allows for the simultaneous determination of both size and concentration of nanoparticles in a sample. This study investigates the accuracy of particle size and concentration measurements performed on an LM10 device. For experiments, standard nanoparticles of different sizes composed of two materials with different refractive indices were used. Particle size measurements were found to have a decent degree of accuracy. This fact was verified by the manufacturer-reported particle size-determined by transmission electron microscopy (TEM)-as well as by performed scanning electron microscopy (SEM) measurements. On the other hand, concentration measurements resulted in overestimation of the particle concentration in majority of cases. Thus, our findings confirmed the accuracy of nanoparticle sizing performed by the LM10 instrument and highlighted the overestimation of particle concentration made by this device. In addition, an approach of swift correction of the results of concentration measurements received for samples is suggested in the presented study.
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- 2020
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11. Surface Plasmon Resonance (SPR)-Based Biosensors as Instruments with High Versatility and Sensitivity.
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Shpacovitch V and Hergenröder R
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- Metals, Biosensing Techniques, Surface Plasmon Resonance
- Abstract
Surface plasmon resonance (SPR), as a physical phenomenon, is not restricted only to events occurring in thin planar metal films [...].
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- 2020
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12. Nanoparticle Classification Using Frequency Domain Analysis on Resource-Limited Platforms.
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Yayla M, Toma A, Chen KH, Lenssen JE, Shpacovitch V, Hergenröder R, Weichert F, and Chen JJ
- Abstract
A mobile system that can detect viruses in real time is urgently needed, due to the combination of virus emergence and evolution with increasing global travel and transport. A biosensor called PAMONO (for Plasmon Assisted Microscopy of Nano-sized Objects) represents a viable technology for mobile real-time detection of viruses and virus-like particles. It could be used for fast and reliable diagnoses in hospitals, airports, the open air, or other settings. For analysis of the images provided by the sensor, state-of-the-art methods based on convolutional neural networks (CNNs) can achieve high accuracy. However, such computationally intensive methods may not be suitable on most mobile systems. In this work, we propose nanoparticle classification approaches based on frequency domain analysis, which are less resource-intensive. We observe that on average the classification takes 29 μ s per image for the Fourier features and 17 μ s for the Haar wavelet features. Although the CNN-based method scores 1-2.5 percentage points higher in classification accuracy, it takes 3370 μ s per image on the same platform. With these results, we identify and explore the trade-off between resource efficiency and classification performance for nanoparticle classification of images provided by the PAMONO sensor.
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- 2019
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13. Optical and surface plasmonic approaches to characterize extracellular vesicles. A review.
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Shpacovitch V and Hergenröder R
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- Animals, Biosensing Techniques instrumentation, Dynamic Light Scattering instrumentation, Dynamic Light Scattering methods, Equipment Design, Flow Cytometry instrumentation, Flow Cytometry methods, Humans, Interferometry instrumentation, Interferometry methods, Microscopy, Atomic Force instrumentation, Microscopy, Atomic Force methods, Microscopy, Electron, Transmission instrumentation, Microscopy, Electron, Transmission methods, Surface Plasmon Resonance instrumentation, Surface Plasmon Resonance methods, Biosensing Techniques methods, Extracellular Vesicles chemistry, Extracellular Vesicles ultrastructure
- Abstract
Extracellular vesicles (EVs) have been recognized as messengers delivering various active molecules between cells. This feature of EVs drew the attention of clinicians as well as researchers from different fields. However, exciting ideas to employ EVs as means of drug delivery or to test them as biomarkers of cellular status require very thoughtful and attentive approaches to the selection of analytical techniques for EV characterization. Optical and surface plasmonic analytical methods offer a researcher an invaluable opportunity to use already sized and/or quantified EVs in further functional cell-based assays and in focused biochemical tests (nucleic acid and protein arrays, etc.). Moreover, a high sensitivity and relative flexibility of surface plasmonic sensors open a possibility to develop instruments performing quantitative, metrical and EV surface/content analysis in a single device. This review aims to consider the applicability of established and modern optical techniques as well as novel surface plasmonic approaches for different aspects of EV analysis., (Copyright © 2017 Elsevier B.V. All rights reserved.)
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- 2018
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14. Application of the PAMONO-Sensor for Quantification of Microvesicles and Determination of Nano-Particle Size Distribution.
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Shpacovitch V, Sidorenko I, Lenssen JE, Temchura V, Weichert F, Müller H, Überla K, Zybin A, Schramm A, and Hergenröder R
- Abstract
The PAMONO-sensor (plasmon assisted microscopy of nano-objects) demonstrated an ability to detect and quantify individual viruses and virus-like particles. However, another group of biological vesicles-microvesicles (100-1000 nm)-also attracts growing interest as biomarkers of different pathologies and needs development of novel techniques for characterization. This work shows the applicability of a PAMONO-sensor for selective detection of microvesicles in aquatic samples. The sensor permits comparison of relative concentrations of microvesicles between samples. We also study a possibility of repeated use of a sensor chip after elution of the microvesicle capturing layer. Moreover, we improve the detection features of the PAMONO-sensor. The detection process utilizes novel machine learning techniques on the sensor image data to estimate particle size distributions of nano-particles in polydisperse samples. Altogether, our findings expand analytical features and the application field of the PAMONO-sensor. They can also serve for a maturation of diagnostic tools based on the PAMONO-sensor platform.
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- 2017
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15. Application of surface plasmon resonance imaging technique for the detection of single spherical biological submicrometer particles.
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Shpacovitch V, Temchura V, Matrosovich M, Hamacher J, Skolnik J, Libuschewski P, Siedhoff D, Weichert F, Marwedel P, Müller H, Überla K, Hergenröder R, and Zybin A
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- HEK293 Cells, HIV chemistry, Humans, Tobacco Mosaic Virus chemistry, Virion chemistry, Water chemistry, Influenza A virus metabolism, Particle Size, Surface Plasmon Resonance methods, Tobacco Mosaic Virus metabolism, Virion metabolism
- Abstract
Recent proof-of-principle studies demonstrated the suitability of the surface plasmon resonance imaging (SPRi) technique for the detection of individual submicrometer and nanoparticles in solutions. In the current study, we used the SPRi technique for visualization of the binding of round-shaped viruses (inactivated influenza A virus) and virus-like particles (human immunodeficiency virus (HIV)-based virus-like particles) to the functionalized sensor surface. We show the applicability of the SPRi technique for the detection of individual virus-like particles in buffers without serum as well as in buffers containing different concentrations of serum. Furthermore, we prove the specificity of visualized binding events using two different pseudotypes of HIV virus-like particles. We also demonstrate the applicability of the SPRi technique for the determination of relative particle concentrations in solutions. Moreover, we suggest a technical approach, which allows enhancing the magnitude of binding signals. Our studies indicate that the SPRi technique represents an efficient research tool for quantification and characterization of biological submicrometer objects such as viruses or virus-like particles, for example., (Copyright © 2015 Elsevier Inc. All rights reserved.)
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- 2015
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16. Proteinase-activated receptor-2 agonist activates anti-influenza mechanisms and modulates IFNγ-induced antiviral pathways in human neutrophils.
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Feld M, Shpacovitch V, Ehrhardt C, Fastrich M, Goerge T, Ludwig S, and Steinhoff M
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- 2',5'-Oligoadenylate Synthetase genetics, Cell Degranulation, Humans, Immunity, Cellular, Influenza A virus genetics, Influenza A virus physiology, Myxovirus Resistance Proteins genetics, Neutrophils immunology, Oligopeptides pharmacology, Peroxidase metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, Reactive Oxygen Species metabolism, Viral Nonstructural Proteins genetics, Virus Replication, Influenza A virus immunology, Interferon-gamma immunology, Neutrophils drug effects, Neutrophils physiology, Receptor, PAR-2 agonists
- Abstract
Proteinase-activated receptor-2 (PAR2) is expressed by human leukocytes and participates in the development of inflammatory diseases. Recent studies demonstrated an ability of PAR2 agonist to enhance IFNγ-induced antiviral responses of human leukocytes. However, the precise cellular antiviral defense mechanisms triggered in leukocytes after stimulation with IFNγ and/or PAR2 agonist remain elusive. Therefore, we aimed to identify neutrophil defense mechanisms involved in antiviral resistance. Here we demonstrated that PAR2 agonist enhanced IFNγ-related reduction of influenza A virus (IAV) replication in human neutrophils. PAR2-mediated decrease in IAV replication was associated with reduced NS-1 transcription. Moreover, PAR2-dependent neutrophil activation resulted in enhanced myeloperoxidase degranulation and extracellular myeloperoxidase disrupted IAV. The production of ROS was elevated in response to PAR2 activation. Interestingly, IFNγ did not influence both effects: PAR2 agonist-triggered myeloperoxidase (MPO) release and reactive oxygen species (ROS) production, which are known to limit IAV infections. In contrast, orthomyxovirus resistance gene A (MxA) protein expression was synergistically elevated through PAR2 agonist and IFNγ in neutrophils. Altogether, these findings emphasize two PAR2-controlled antiviral mechanisms that are independent of or modulated by IFNγ.
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- 2013
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17. α-1-Antitrypsin and IFN-γ reduce the severity of IC-mediated vasculitis by regulation of leukocyte recruitment in vivo.
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Feld M, Goerge T, Hillgruber C, Steingräber AK, Fastrich M, Shpacovitch V, and Steinhoff M
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- Animals, Arthus Reaction drug therapy, Capillary Permeability drug effects, Chemokine CXCL1 pharmacology, Edema drug therapy, Male, Mice, Mice, Inbred C57BL, Severity of Illness Index, Interferon-gamma administration & dosage, Neutrophils drug effects, Recombinant Proteins administration & dosage, Trypsin Inhibitors administration & dosage, Vasculitis, Leukocytoclastic, Cutaneous drug therapy, alpha 1-Antitrypsin administration & dosage
- Abstract
IC-mediated vasculitis (ICV) can be life threatening. The cellular and immune mechanisms controlling ICV are poorly understood. Therefore, we investigated the role of α-1-antitrypsin (α1AT) and IFN-γ in reducing the severity of ICV in a mouse model in vivo. To induce ICV, mice were challenged with the reverse passive Arthus reaction (RPA), the prototypic in vivo model for leukocytoclastic vasculitis (LcV), and the modulation of vascular permeability, edema formation, and leukocyte recruitment was studied. To further analyze the dynamics of RPA, we applied intravital microscopy in the dorsal skinfold chamber. α1AT continuously led to reduced leukocyte recruitment. α1AT interfered with neutrophil recruitment through a KC-dependent mechanism and reduced KC-elicited neutrophil activation. In contrast to α1AT, IFN-γ-reduced leukocyte recruitment during RPA was clearly independent of KC. We also revealed that the recruitment of neutrophils during RPA was a prerequisite for full KC expression. Thus, therapeutic administration of α1AT and IFN-γ might be beneficial for limiting the duration and severity of ICV.
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- 2012
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18. Y-box protein-1/p18 fragment identifies malignancies in patients with chronic liver disease.
- Author
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Tacke F, Kanig N, En-Nia A, Kaehne T, Eberhardt CS, Shpacovitch V, Trautwein C, and Mertens PR
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- Adolescent, Adult, Aged, Aged, 80 and over, Amino Acid Sequence, Biomarkers, Tumor blood, Chronic Disease, Female, Humans, Inflammation blood, Male, Middle Aged, Molecular Sequence Data, Renal Insufficiency blood, Sensitivity and Specificity, Sequence Alignment, Young Adult, Carcinoma, Hepatocellular blood, Carcinoma, Hepatocellular complications, Liver Diseases blood, Liver Diseases complications, Liver Neoplasms blood, Liver Neoplasms complications, Y-Box-Binding Protein 1 blood
- Abstract
Background: Immunohistochemical detection of cold shock proteins is predictive for deleterious outcome in various malignant diseases. We recently described active secretion of a family member, denoted Y-box (YB) protein-1. We tested the clinical and diagnostic value of YB-1 protein fragment p18 (YB-1/p18) detection in blood for malignant diseases., Methods: We used a novel monoclonal anti-YB-1 antibody to detect YB-1/p18 by immunoblotting in plasma samples of healthy volunteers (n=33), patients with non-cancerous, mostly inflammatory diseases (n=60), hepatocellular carcinoma (HCC; n=25) and advanced solid tumors (n=20). YB-1/p18 was then tested in 111 patients with chronic liver diseases, alongside established tumor markers and various diagnostic measures, during evaluation for potential liver transplantation., Results: We developed a novel immunoblot to detect the 18 kD fragment of secreted YB-1 in human plasma (YB-1/p18) that contains the cold-shock domains (CSD) 1-3 of the full-length protein. YB-1/p18 was detected in 11/25 HCC and 16/20 advanced carcinomas compared to 0/33 healthy volunteers and 10/60 patients with non-cancerous diseases. In 111 patients with chronic liver disease, YB-1/p18 was detected in 20 samples. Its occurrence was not associated with advanced Child stages of liver cirrhosis or liver function. In this cohort, YB-1/p18 was not a good marker for HCC, but proved most powerful in detecting malignancies other than HCC (60% positive) with a lower rate of false-positive results compared to established tumor markers. Alpha-fetoprotein (AFP) was most sensitive in detecting HCC, but simultaneous assessment of AFP, CA19-9 and YB-1/p18 improved overall identification of HCC patients., Conclusions: Plasma YB-1/p18 can identify patients with malignancies, independent of acute inflammation, renal impairment or liver dysfunction. The detection of YB-1/p18 in human plasma may have potential as a tumor marker for screening of high-risk populations, e.g. before organ transplantation, and should therefore be evaluated in larger prospective studies.
- Published
- 2011
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19. Pituitary adenylate cyclase activating polypeptide: an important vascular regulator in human skin in vivo.
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Seeliger S, Buddenkotte J, Schmidt-Choudhury A, Rosignoli C, Shpacovitch V, von Arnim U, Metze D, Rukwied R, Schmelz M, Paus R, Voegel JJ, Schmidt WE, and Steinhoff M
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- Adult, Humans, Male, Pituitary Adenylate Cyclase-Activating Polypeptide pharmacology, Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I genetics, Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I metabolism, Receptors, Vasoactive Intestinal Peptide, Type II genetics, Receptors, Vasoactive Intestinal Peptide, Type II metabolism, Receptors, Vasoactive Intestinal Polypeptide, Type I genetics, Receptors, Vasoactive Intestinal Polypeptide, Type I metabolism, Regional Blood Flow, Skin drug effects, Tissue Culture Techniques, Urticaria metabolism, Urticaria pathology, Vasoactive Intestinal Peptide metabolism, Vasoactive Intestinal Peptide pharmacology, Young Adult, Pituitary Adenylate Cyclase-Activating Polypeptide metabolism, Skin blood supply, Skin metabolism
- Abstract
Pituitary adenylate cyclase-activating peptide (PACAP) is an important neuropeptide and immunomodulator in various tissues. Although this peptide and its receptors (ie, VPAC1R, VPAC2R, and PAC1R) are expressed in human skin, their biological roles are unknown. Therefore, we tested whether PACAP regulates vascular responses in human skin in vivo. When injected intravenously, PACAP induced a significant, concentration-dependent vascular response (ie, flush, erythema, edema) and mediated a significant and concentration-dependent increase in intrarectal body temperature that peaked at 2.7°C. Topical application of PACAP induced marked concentration-dependent edema. Immunohistochemistry revealed a close association of PACAP-immunoreactive nerve fibers with mast cells and dermal blood vessels. VPAC1R was expressed by dermal endothelial cells, CD4+ and CD8+ T cells, mast cells, and keratinocytes, whereas VPAC2R was expressed only in keratinocytes. VPAC1R protein and mRNA were also detected in human dermal microvascular endothelial cells. The PACAP-induced change in cAMP production in these cells demonstrated VPAC1R to be functional. PACAP treatment of organ-cultured human skin strongly increased the number of CD31+ vessel cross-sections. Taken together, these results suggest that PACAP directly induces vascular responses that may be associated with neurogenic inflammation, indicating for the first time that PACAP may be a crucial vascular regulator in human skin in vivo. Antagonists to PACAP function may be beneficial for the treatment of inflammatory skin diseases with a neurogenic component.
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- 2010
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20. Tumor-derived matrix metalloproteinase-1 targets endothelial proteinase-activated receptor 1 promoting endothelial cell activation.
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Goerge T, Barg A, Schnaeker EM, Poppelmann B, Shpacovitch V, Rattenholl A, Maaser C, Luger TA, Steinhoff M, and Schneider SW
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- Animals, Caco-2 Cells, Calcium metabolism, Cattle, Colonic Neoplasms blood supply, Colonic Neoplasms enzymology, Endothelial Cells cytology, HT29 Cells, Humans, Matrix Metalloproteinase Inhibitors, Melanoma blood supply, Melanoma enzymology, Receptor, PAR-1 antagonists & inhibitors, Colonic Neoplasms metabolism, Endothelial Cells metabolism, Matrix Metalloproteinase 1 metabolism, Melanoma metabolism, Receptor, PAR-1 metabolism
- Abstract
In the vascular system, circulating tumor cells interact with endothelial cells. Tumor-endothelial cross-talk transforms the intravascular milieu to a prothrombotic, proinflammatory, and cell-adhesive state called endothelial cell activation (ECA). In the present study, we analyze the potential of metastatic tumor-derived soluble factors to transform the vascular endothelium into a prothrombotic and proinflammatory activated state. Supernatant from cultured melanoma and colon cancer cells (A375, WM9, A7, and HT-29) induced an acute activation of macrovascular and microvascular endothelial cells (human umbilical vein endothelial cells and human dermal microvascular endothelial cells) as shown by intracellular calcium flux and secretion of von Willebrand factor and interleukin-8, all markers of acute ECA. This process was inhibited using specific proteinase-activated receptor 1 (PAR1) inhibitors (RWJ-58259 and SCH-79797), indicating a mediating role for endothelial thrombin receptors. Immunofluorescence, Western blot analysis, and collagenase activity assay of tumor cells and culture supernatant revealed the presence of matrix metalloproteinase-1 (MMP-1), a recently described activator of PAR1. Inhibition of MMP-1 in supernatant from cultured tumor cells significantly attenuated ECA. Additional studies using isolated human MMP-1 (5 nmol/L) proved the presence of a functional MMP-1/PAR1 axis in tumor-endothelial communication. These findings show a new pathway of tumor-endothelial cross-talk via an intravascular MMP1/PAR1 axis in microvascular and macrovascular endothelium. Inhibition of this cross-talk may be a powerful means to prevent tumor-induced ECA and thus thrombotic and inflammatory cell adhesion.
- Published
- 2006
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21. Proteinase-activated receptors: transducers of proteinase-mediated signaling in inflammation and immune response.
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Steinhoff M, Buddenkotte J, Shpacovitch V, Rattenholl A, Moormann C, Vergnolle N, Luger TA, and Hollenberg MD
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- Amino Acid Sequence, Animals, Blood Platelets, Cardiovascular Diseases drug therapy, Endothelial Cells, GTP-Binding Proteins physiology, Humans, Molecular Sequence Data, Organ Specificity, Receptors, Proteinase-Activated analysis, Receptors, Proteinase-Activated antagonists & inhibitors, Receptors, Proteinase-Activated chemistry, Species Specificity, Immunity, Inflammation, Peptide Hydrolases physiology, Receptors, Proteinase-Activated physiology, Signal Transduction physiology
- Abstract
Serine proteinases such as thrombin, mast cell tryptase, trypsin, or cathepsin G, for example, are highly active mediators with diverse biological activities. So far, proteinases have been considered to act primarily as degradative enzymes in the extracellular space. However, their biological actions in tissues and cells suggest important roles as a part of the body's hormonal communication system during inflammation and immune response. These effects can be attributed to the activation of a new subfamily of G protein-coupled receptors, termed proteinase-activated receptors (PARs). Four members of the PAR family have been cloned so far. Thus, certain proteinases act as signaling molecules that specifically regulate cells by activating PARs. After stimulation, PARs couple to various G proteins and activate signal transduction pathways resulting in the rapid transcription of genes that are involved in inflammation. For example, PARs are widely expressed by cells involved in immune responses and inflammation, regulate endothelial-leukocyte interactions, and modulate the secretion of inflammatory mediators or neuropeptides. Together, the PAR family necessitates a paradigm shift in thinking about hormone action, to include proteinases as key modulators of biological function. Novel compounds that can modulate PAR function may be potent candidates for the treatment of inflammatory or immune diseases.
- Published
- 2005
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22. Expression of vanilloid receptor subtype 1 in cutaneous sensory nerve fibers, mast cells, and epithelial cells of appendage structures.
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Ständer S, Moormann C, Schumacher M, Buddenkotte J, Artuc M, Shpacovitch V, Brzoska T, Lippert U, Henz BM, Luger TA, Metze D, and Steinhoff M
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- Adolescent, Adult, Aged, Animals, Biopsy, Brain metabolism, Calcitonin Gene-Related Peptide metabolism, Capillaries metabolism, Capsaicin metabolism, Capsaicin therapeutic use, Cell Line, Child, Eccrine Glands metabolism, Epidermal Cells, Epidermis metabolism, Epithelial Cells cytology, Gene Expression, Hair Follicle metabolism, Humans, Mast Cells cytology, Middle Aged, Nerve Fibers metabolism, Neurons, Afferent ultrastructure, Nociceptors physiology, Pruritus drug therapy, Pruritus pathology, Rats, Receptors, Drug metabolism, Sebaceous Glands metabolism, Spinal Cord metabolism, Substance P metabolism, Epidermis innervation, Epithelial Cells physiology, Mast Cells physiology, Neurons, Afferent physiology, Pruritus physiopathology, Receptors, Drug genetics
- Abstract
The vanilloid receptor subtype 1 (VR1)/(TRPV1), binding capsaicin, is a non-selective cation channel that recently has been shown in human keratinocytes in vitro and in vivo. However, a description of VR1 localization in other cutaneous compartments in particular cutaneous nerve fibers is still lacking. We therefore investigated VR1 immunoreactivity as well as mRNA and protein expression in a series (n = 26) of normal (n = 7), diseased (n = 13) [prurigo nodularis (PN) (n = 10), generalized pruritus (n = 1), and mastocytosis (n = 2)], and capsaicin-treated human skin (n = 6). VR1 immunoreactivity could be observed in cutaneous sensory nerve fibers, mast cells, epidermal keratinocytes, dermal blood vessels, the inner root sheet and the infundibulum of hair follicles, differentiated sebocytes, sweat gland ducts, and the secretory portion of eccrine sweat glands. Upon reverse transcriptase-polymerase chain reaction and Western blot analysis, VR1 was detected in mast cells and keratinocytes from human skin. In pruritic skin of PN, VR1 expression was highly increased in epidermal keratinocytes and nerve fibers, which was normalized after capsaicin application. During capsaicin therapy, a reduction of neuropeptides (substance P, calcitonin gene-related peptide) was observed. After cessation of capsaicin therapy, neuropeptides re-accumulated in skin nerves. In conclusion, VR1 is widely distributed in the skin, suggesting a major role for this receptor, e.g. in nociception and neurogenic inflammation.
- Published
- 2004
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