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Thomas A. Horbett - One of the best experts on this subject based on the ideXlab platform.
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Platelet adhesion to radiofrequency glow-discharge-deposited fluorocarbon polymers preAdsorbed with selectively depleted plasmas show the primary role of Fibrinogen.
Journal of Biomaterials Science Polymer Edition, 2004Co-Authors: Wei-bor Tsai, J. M. Grunkemeier, Q. Shi, Clive D. Mcfarland, Thomas A. HorbettAbstract:Fluorocarbon radio-frequency glow-discharge (RFGD) treatment has previously been shown to cause decreased platelet adhesion despite the presence of Adsorbed Fibrinogen on the surfaces. In this study platelet adhesion to fluorocarbon RFGD-treated surfaces preAdsorbed with human plasma was further examined. A series of plasma deposited fluorocarbon thin films were made by varying the C3F6/CH4 ratio in the monomer feed. The surfaces were preAdsorbed with plasma, serum, or plasma selectively depleted of fibronectin, vitronectin, or Von Willebrand factor, and platelet adhesion was measured. We also measured Fibrinogen adsorption to the surfaces from plasma, monoclonal antibody binding to Adsorbed Fibrinogen and SDS elutability of the Adsorbed Fibrinogen. The antibodies used bind to the three putative platelet binding sites on Fibrinogen, namely, M1 antibody binds to the dodecapeptide at the C-terminus of the gamma chain, γ (402–411), R1 antibody binds to a sequence in the Aα chain (87–100) which includes RGDF ...
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Variations in the ability of Adsorbed Fibrinogen to mediate platelet adhesion to polystyrene-based materials: A multivariate statistical analysis of antibody binding to the platelet binding sites of Fibrinogen
Journal of biomedical materials research. Part A, 2003Co-Authors: Wei-bor Tsai, J. M. Grunkemeier, Thomas A. HorbettAbstract:Platelet adhesion to the surfaces of biomaterials preAdsorbed with plasma previously has been shown to be mediated exclusively by surface-bound Fibrinogen and does not seem to involve the other adhesion proteins in plasma (Tsai et al., J Biomed Mater Res 2002;60:348–359). In this study, the influence of surface-bound Fibrinogen on platelet adhesion to five different types of polystyrene-based microtiter plates preAdsorbed with plasma was analyzed relative to the amount of Adsorbed Fibrinogen and monoclonal antibody binding to the Adsorbed Fibrinogen. There was no significant correlation between platelet adhesion and the absolute amount of Adsorbed Fibrinogen. However, platelet adhesion was positively correlated to the ability of the Adsorbed Fibrinogen to bind three types of monoclonal antibodies. The antibodies used bound to the sites on Fibrinogen thought to be involved in platelet binding (the two γ chain C-terminal dodecapeptides and the RGDF and RGDS sequences in each of the Aα chains). A partial least-squares calibration model was used to analyze the relative importance of these binding sites in Fibrinogen to platelet adhesion. The γ chain C-terminal dodecapeptide was shown to be the most important site in Adsorbed Fibrinogen in mediating platelet adhesion. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 1255–1268, 2003
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Characterization of the structure of binary and ternary Adsorbed protein films using electron spectroscopy for chemical analysis, time-of-flight secondary ion mass spectrometry, and radiolabeling
Langmuir, 2003Co-Authors: Matthew Scott Wagner, Thomas A. Horbett, David G. CastnerAbstract:In complex Adsorbed protein films, the biological reactivity of the Adsorbed proteins depends on their relative concentrations, organization, conformation, and orientation. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) samples the outermost composition of an Adsorbed protein film, providing biologically relevant information about the organization and availability of the Adsorbed proteins in the film. We have previously shown that ToF-SIMS can quantitatively measure the composition of binary Adsorbed protein films. However, for one particular binary system studied (immunoglobulin G−Fibrinogen), a difference between the ToF-SIMS and 125I-radiolabeled protein adsorption measurements was reported. It was hypothesized that the composition of the protein film at its outermost (and, therefore, most biologically relevant) surface was different than that of the overall protein film due to the protrusion of the Adsorbed Fibrinogen over the Adsorbed immunoglobulin G. This study provides further evidence ...
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Co-Adsorbed Fibrinogen and von Willebrand factor augment platelet procoagulant activity and spreading.
Journal of Biomaterials Science Polymer Edition, 2001Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, Thomas A. HorbettAbstract:Previously we observed that platelets adherent to surfaces preAdsorbed with blood plasma exhibited 1.3 to 2.4 times greater procoagulant activity than platelets on surfaces Adsorbed with Fibrinogen (Fg) only. These observations suggested that the adhesion proteins Adsorbed from plasma may activate platelets in a cooperative, or synergistic manner. In the present study, polystyrene surfaces Adsorbed with both Fg and vWF induced up to three times greater procoagulant activity than surfaces Adsorbed with Fg or vWF only. The amounts of Fg and vWF Adsorbed from binary mixtures that resulted in increased procoagulant activity were found to be similar to the amounts that Adsorbed to PS from 100% plasma. The effect of Adsorbed adhesion proteins on platelet spreading was also investigated. The proportion of fully spread platelets increased, depending on the adhesion protein preAdsorbed to the surface, in the following order: vWF < Fg < Fn < (vWF + Fg) < Vn < plasma.
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the effect of Adsorbed Fibrinogen fibronectin von willebrand factor and vitronectin on the procoagulant state of adherent platelets
Biomaterials, 2000Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, Clive D. Mcfarland, Thomas A. HorbettAbstract:Procoagulant (activated) platelets provide a site for assembly of the prothrombinase complex which can rapidly convert prothrombin into thrombin (a potent inducer of clot formation). Previously, we reported that adhesion of platelets to surfaces preAdsorbed with blood plasma caused them to become procoagulant. In the present study we investigated the effect of Adsorbed adhesion proteins (Fibrinogen (Fg), fibronectin (Fn), von Willebrand factor (vWF) and vitronectin (Vn)) on the procoagulant activity of adherent platelets. Adsorbed Fn, vWF and Fg promoted platelet adhesion in the following order: Fn
J. M. Grunkemeier - One of the best experts on this subject based on the ideXlab platform.
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Platelet adhesion to radiofrequency glow-discharge-deposited fluorocarbon polymers preAdsorbed with selectively depleted plasmas show the primary role of Fibrinogen.
Journal of Biomaterials Science Polymer Edition, 2004Co-Authors: Wei-bor Tsai, J. M. Grunkemeier, Q. Shi, Clive D. Mcfarland, Thomas A. HorbettAbstract:Fluorocarbon radio-frequency glow-discharge (RFGD) treatment has previously been shown to cause decreased platelet adhesion despite the presence of Adsorbed Fibrinogen on the surfaces. In this study platelet adhesion to fluorocarbon RFGD-treated surfaces preAdsorbed with human plasma was further examined. A series of plasma deposited fluorocarbon thin films were made by varying the C3F6/CH4 ratio in the monomer feed. The surfaces were preAdsorbed with plasma, serum, or plasma selectively depleted of fibronectin, vitronectin, or Von Willebrand factor, and platelet adhesion was measured. We also measured Fibrinogen adsorption to the surfaces from plasma, monoclonal antibody binding to Adsorbed Fibrinogen and SDS elutability of the Adsorbed Fibrinogen. The antibodies used bind to the three putative platelet binding sites on Fibrinogen, namely, M1 antibody binds to the dodecapeptide at the C-terminus of the gamma chain, γ (402–411), R1 antibody binds to a sequence in the Aα chain (87–100) which includes RGDF ...
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Variations in the ability of Adsorbed Fibrinogen to mediate platelet adhesion to polystyrene-based materials: A multivariate statistical analysis of antibody binding to the platelet binding sites of Fibrinogen
Journal of biomedical materials research. Part A, 2003Co-Authors: Wei-bor Tsai, J. M. Grunkemeier, Thomas A. HorbettAbstract:Platelet adhesion to the surfaces of biomaterials preAdsorbed with plasma previously has been shown to be mediated exclusively by surface-bound Fibrinogen and does not seem to involve the other adhesion proteins in plasma (Tsai et al., J Biomed Mater Res 2002;60:348–359). In this study, the influence of surface-bound Fibrinogen on platelet adhesion to five different types of polystyrene-based microtiter plates preAdsorbed with plasma was analyzed relative to the amount of Adsorbed Fibrinogen and monoclonal antibody binding to the Adsorbed Fibrinogen. There was no significant correlation between platelet adhesion and the absolute amount of Adsorbed Fibrinogen. However, platelet adhesion was positively correlated to the ability of the Adsorbed Fibrinogen to bind three types of monoclonal antibodies. The antibodies used bound to the sites on Fibrinogen thought to be involved in platelet binding (the two γ chain C-terminal dodecapeptides and the RGDF and RGDS sequences in each of the Aα chains). A partial least-squares calibration model was used to analyze the relative importance of these binding sites in Fibrinogen to platelet adhesion. The γ chain C-terminal dodecapeptide was shown to be the most important site in Adsorbed Fibrinogen in mediating platelet adhesion. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 1255–1268, 2003
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Co-Adsorbed Fibrinogen and von Willebrand factor augment platelet procoagulant activity and spreading.
Journal of Biomaterials Science Polymer Edition, 2001Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, Thomas A. HorbettAbstract:Previously we observed that platelets adherent to surfaces preAdsorbed with blood plasma exhibited 1.3 to 2.4 times greater procoagulant activity than platelets on surfaces Adsorbed with Fibrinogen (Fg) only. These observations suggested that the adhesion proteins Adsorbed from plasma may activate platelets in a cooperative, or synergistic manner. In the present study, polystyrene surfaces Adsorbed with both Fg and vWF induced up to three times greater procoagulant activity than surfaces Adsorbed with Fg or vWF only. The amounts of Fg and vWF Adsorbed from binary mixtures that resulted in increased procoagulant activity were found to be similar to the amounts that Adsorbed to PS from 100% plasma. The effect of Adsorbed adhesion proteins on platelet spreading was also investigated. The proportion of fully spread platelets increased, depending on the adhesion protein preAdsorbed to the surface, in the following order: vWF < Fg < Fn < (vWF + Fg) < Vn < plasma.
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the effect of Adsorbed Fibrinogen fibronectin von willebrand factor and vitronectin on the procoagulant state of adherent platelets
Biomaterials, 2000Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, Clive D. Mcfarland, Thomas A. HorbettAbstract:Procoagulant (activated) platelets provide a site for assembly of the prothrombinase complex which can rapidly convert prothrombin into thrombin (a potent inducer of clot formation). Previously, we reported that adhesion of platelets to surfaces preAdsorbed with blood plasma caused them to become procoagulant. In the present study we investigated the effect of Adsorbed adhesion proteins (Fibrinogen (Fg), fibronectin (Fn), von Willebrand factor (vWF) and vitronectin (Vn)) on the procoagulant activity of adherent platelets. Adsorbed Fn, vWF and Fg promoted platelet adhesion in the following order: Fn
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Platelet adhesion and procoagulant activity induced by contact with radiofrequency glow discharge polymers: roles of Adsorbed Fibrinogen and vWF.
Journal of Biomedical Materials Research, 2000Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, David G. Castner, Morgan R. Alexander, Thomas A. HorbettAbstract:The potential hemocompatibility of radiofrequency glow discharge (RFGD) polymers made by copolymerization of mixtures of hexafluoropropene and ethylene (C3F6/C2H4) or acrylic acid and 1,7-octadiene was investigated using in vitro assays for platelet adhesion and platelet catalyzed thrombin generation. Thrombin generation rate normalized to platelet number was used as a measurement of platelet activation (procoagulant activity). RFGD polymers produced by copolymerization of acrylic acid and 1,7-octadiene contained varying amounts of carboxylic acid species as determined by electron spectroscopy for chemical analysis (ESCA). These polymers induced little variation in platelet adhesion, thrombin generation, or platelet activation. RFGD polymerization of C3F6 and C2H4 resulted in polymers with varying proportions of fluorinated species, as determined by ESCA. Fibrinogen adsorption from plasma was maximal on a polymer made with 25% C3F6 (75% C2H4) in the feed. However von Willebrand factor (vWF) adsorption was greater on polymers made with increased %C3F6 in the feed. Platelet adhesion decreased with increasing %C3F6 in the feed. Thrombin generation was lowest for platelets adherent to polymers made from both C3F6 and C2H4. Therefore, procoagulant activity of platelets increased for polymers made with increased %C3F6 in the feed, similar to the trend in vWF adsorption. These findings suggest that increased incorporation of fluorinated species into RFGD polymers leads to decreased platelet adhesion and increased platelet activation (which is possibly due to increased vWF adsorption). © 2000 John Wiley & Sons, Inc. J Biomed Mater Res, 51, 669–679, 2000.
Nan Huang - One of the best experts on this subject based on the ideXlab platform.
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mussel inspired one step adherent coating rich in amine groups for covalent immobilization of heparin hemocompatibility growth behaviors of vascular cells and tissue response
ACS Applied Materials & Interfaces, 2014Co-Authors: Ying Yang, Manfred F. Maitz, Pengkai Qi, Xiangyang Li, Zhilu Yang, Ru Shen, Qiufen Tu, Nan HuangAbstract:Heparin, an important polysaccharide, has been widely used for coatings of cardiovascular devices because of its multiple biological functions including anticoagulation and inhibition of intimal hyperplasia. In this study, surface heparinization of a commonly used 316L stainless steel (SS) was explored for preparation of a multifunctional vascular stent. Dip-coating of the stents in an aqueous solution of dopamine and hexamethylendiamine (HD) (PDAM/HD) was presented as a facile method to form an adhesive coating rich in primary amine groups, which was used for covalent heparin immobilization via active ester chemistry. A heparin grafting density of about 900 ng/cm2 was achieved with this method. The retained bioactivity of the immobilized heparin was confirmed by a remarkable prolongation of the activated partial thromboplastin time (APTT) for about 15 s, suppression of platelet adhesion, and prevention of the denaturation of Adsorbed Fibrinogen. The Hep-PDAM/HD also presented a favorable microenvironment...
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Real-Time Characterization of Fibrinogen Interaction with Modified Titanium Dioxide Film by Quartz Crystal Microbalance with Dissipation
Chinese Journal of Chemical Physics, 2014Co-Authors: Ansha Zhao, Manfred F. Maitz, Zhao Wang, Xiao-hua Zhu, Nan HuangAbstract:The adsorption of Fibrinogen can be used as a quick indicator of surface haemocompatibility because of its prominent role in coagulation and platelet adhesion. In this work the molecular interaction between Fibrinogen and a modified titanium oxide surface/platelet has been studied by quartz crystal microbalance with dissipation (QCM-D) in situ. In order to further characterize the conformation of Adsorbed Fibrinogen, αC and γ-chain antibody were used to check the orientation and denaturation of Fibrinogen on solid surface. QCM-D investigations revealed the Fibrinogen have the trend to adsorb on hydrophilic surface in a side-on orientation by positively charged αC domains, which would reduce the exposure of platelet bonding site on γ chain and enable less platelet adhesion and be activated. These observations suggest that certain conformations of Adsorbed Fibrinogen are less platelet adhesive than others, which opens a possibility for creating a non-platelet adhesive substrates.
Buddy D Ratner - One of the best experts on this subject based on the ideXlab platform.
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Stepwise assembly of fibrin bilayers on self-assembled monolayers of alkanethiolates : Influence of surface chemistry
The Journal of Physical Chemistry C, 2007Co-Authors: Hua Wang, Buddy D Ratner, E. Helene Sage, Shaoyi JiangAbstract:Fibrin bilayers are formed in a stepwise manner on four model surfaces: hydrophobic, neutral hydrophilic, positively charged, and negatively charged. These surfaces are self-assembled monolayers (SAMs) of alkanethiolates on gold with different terminal groups. A surface plasmon resonance (SPR) sensor is used to monitor the formation of fibrin bilayers in real time. The structures of the fibrin bilayers formed on SAMs of different surface chemistries are proposed, based on the amount of Fibrinogen in each layer. The efficiency of the physically Adsorbed Fibrinogen to promote fibrin formation is assessed by the ratio of the amount of Fibrinogen in the second layer to that in the first layer. It is shown for the first time that the orientation/ conformation of an Adsorbed Fibrinogen layer determined by underlying surface chemistry affects its reactivity with soluble Fibrinogen, resulting in fibrin bilayers with different molecular arrangements. Bovine aortic endothelial cells cultured on fibrin bilayers formed on CH 3 - and OH- SAMs exhibited different morphologies and growth characteristics. Results show that fibrin bilayers with different molecular arrangements and thus different mechanochemical properties lead to different cellular responses.
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Imaging Fibrinogen Adsorbed on noble metal surfaces with scanning tunneling microscopy: correlation of images with electron spectroscopy for chemical analysis, secondary ion mass spectrometry, and radiolabeling studies
Colloids and Surfaces B: Biointerfaces, 1996Co-Authors: Kenneth B. Lewis, Buddy D RatnerAbstract:Abstract Fibrinogen adsorption on gold and platinum surfaces has been studied with electron spectroscopy for chemical analysis (ESCA), secondary ion mass spectrometry (SIMS), 125 I labeling, and scanning tunneling microscopy (STM). Stable images of single molecules have been obtained, but are rare. ESCA, SIMS, and labeling studies confirm that absorbed Fibrinogen is present on samples at monolayer and submonolayer coverages even when STM images show only a bare substrate. Imaging is more reproducible at high coverages at which single molecules cannot be resolved. Possible explanations for the failure of STM to observe Adsorbed Fibrinogen molecules are discussed.
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Postadsorptive transitions in Fibrinogen Adsorbed to polyurethanes: changes in antibody binding and sodium dodecyl sulfate elutability.
Journal of Biomedical Materials Research, 1992Co-Authors: Joseph A Chinn, Thomas A. Horbett, Sylvia E Posso, Buddy D RatnerAbstract:Residence time-dependent changes in Fibrinogen after adsorption to six different polyurethanes were examined by measuring polyclonal antiFibrinogen binding to the Adsorbed protein. The amount of Adsorbed Fibrinogen that could be eluted by sodium dodecyl sulfate (SDS) was also measured. Baboon Fibrinogen was first Adsorbed from dilute plasma to the polymers, which were then stored in either buffer or buffered albumin solution prior to testing. Subsequently, the amount of antiFibrinogen bound by the Adsorbed Fibrinogen was measured using a direct enzyme linked immunosorbent assay (ELISA). Alternatively, the surface with the Adsorbed Fibrinogen was soaked in a 3% SDS solution, and the amount of retained 125I-radiolabeled Fibrinogen was measured. With increasing residence time, decreases in both antibody binding and the SDS elutability of the Adsorbed Fibrinogen occurred, but the rate of change was dependent on the polyurethane to which the Fibrinogen was Adsorbed. In addition, the antibody binding per unit of Adsorbed Fibrinogen, when measured immediately after the adsorption step, varied by approximately a factor of 3 among the various polyurethanes. When the protein-coated surfaces were stored in buffered albumin solution rather than buffer, the decrease in the reactivity of Fibrinogen with residence time did not occur on some of the surfaces. This study shows that the chemical properties of the adsorbing surface influence the rate at which Adsorbed Fibrinogen undergoes change. The significance of the polymer-dependent changes in Adsorbed Fibrinogen with respect to blood reactions with polymers is discussed.
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Adsorption of baboon Fibrinogen and the adhesion of platelets to a thin film polymer deposited by radio-frequency glow discharge of allylamine.
Biomaterials, 1992Co-Authors: Joseph A Chinn, Buddy D Ratner, Thomas A. HorbettAbstract:Platelet adhesion under static and flow conditions from a washed platelet suspension containing albumin to a polymer deposited by radio-frequency glow discharge of allylamine vapour on a poly(ethylene terephthalate) substrate was measured. Electron spectroscopy for chemical analysis was used to characterize the surface. Fibrinogen adsorption from a series of dilute plasma solutions to radio-frequency glow discharge/allylamine, measured using 125l radiolabelled baboon Fibrinogen, increased with decreasing plasma dilution to a level much higher than that previously observed on polyurethanes. Elutability by sodium dodecyl sulphate of Fibrinogen Adsorbed from dilute plasma also increased with increasing plasma concentration, but Fibrinogen preAdsorbed from plasma became non-elutable when surfaces were stored in buffer for 5 d before contact with sodium dodecyl sulphate. Platelet adhesion to substrates which had been pre-Adsorbed with dilute plasma was measured using baboon platelets radiolabelled with 111In. Adhesion greatly decreased as the plasma concentration used for preadsorption increased, suggesting that non-specific platelet binding to the bare surface occurs when protein coverage is incomplete. Non-specific platelet binding was inhibited to varying degrees by preadsorption of different proteins to the surface. Platelet adhesion to surfaces preAdsorbed with dilute (1.0%) baboon and human plasmas lacking Fibrinogen (i.e. serum, heatdeFibrinogenated plasma and congenially aFibrinogenemic plasma) was diminished compared with normal plasma. Addition of exogenous Fibrinogen to the deficient plasma partially restored platelet adhesion to normal levels. Adhesion to surfaces preAdsorbed with human plasma deficient in von Willebrand factor was comparable to that observed with normal plasma. The plasma preadsorption studies with Fibrinogen deficient media suggested that Adsorbed Fibrinogen is necessary for platelet adhesion to the radio-frequency glow discharge/allylamine substrate at high protein coverage. However, since adhesion was greatly reduced when the plasma preAdsorbed substrate was stored in buffer before platelet contact, the conformation of Adsorbed Fibrinogen is also important in mediating platelet adhesion to radio-frequency glow discharge.
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postadsorptive transitions in Fibrinogen Adsorbed to biomer changes in baboon platelet adhesion antibody binding and sodium dodecyl sulfate elutability
Journal of Biomedical Materials Research, 1991Co-Authors: Joseph A Chinn, Thomas A. Horbett, Sylvia E Posso, Buddy D RatnerAbstract:Residence-time-dependent changes in Fibrinogen after its adsorption to Biomer were examined by measuring platelet adhesion and antibody binding to the Adsorbed protein, and the amount of Adsorbed Fibrinogen which could be eluted by sodium dodecyl sulfate (SDS). Baboon Fibrinogen was first Adsorbed (from either pure solution or dilute plasma) to Biomer, which was then stored in either buffer or buffered albumin solution prior to testing. Subsequently, the adherent protein layer was either probed for Fibrinogen capable of mediating platelet adhesion using 111In radiolabeled, washed platelet suspensions under both static and shearing conditions, or for Fibrinogen capable of binding antibody using a direct enzyme linked immunosorbent assay (ELISA). Alternatively, the surface with the Adsorbed protein layer was soaked in a 3% SDS solution, and the amount of 125I radiolabeled Fibrinogen retained was measured. Decreases in platelet and antibody binding, and in the SDS elutability of the Adsorbed Fibrinogen after it was stored in buffer were detected, although different rates of decrease were observed for each method. When the protein-coated surfaces were stored in buffered albumin solution rather than buffer, the decrease in the reactivity of Fibrinogen was prevented. While each of the three assays measures a different property of Adsorbed Fibrinogen, this study suggests that the adherent protein undergoes time dependent conformational changes which render it less reactive toward platelets and antibodies, and more resistant to elution by SDS.
Wei-bor Tsai - One of the best experts on this subject based on the ideXlab platform.
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Platelet adhesion to radiofrequency glow-discharge-deposited fluorocarbon polymers preAdsorbed with selectively depleted plasmas show the primary role of Fibrinogen.
Journal of Biomaterials Science Polymer Edition, 2004Co-Authors: Wei-bor Tsai, J. M. Grunkemeier, Q. Shi, Clive D. Mcfarland, Thomas A. HorbettAbstract:Fluorocarbon radio-frequency glow-discharge (RFGD) treatment has previously been shown to cause decreased platelet adhesion despite the presence of Adsorbed Fibrinogen on the surfaces. In this study platelet adhesion to fluorocarbon RFGD-treated surfaces preAdsorbed with human plasma was further examined. A series of plasma deposited fluorocarbon thin films were made by varying the C3F6/CH4 ratio in the monomer feed. The surfaces were preAdsorbed with plasma, serum, or plasma selectively depleted of fibronectin, vitronectin, or Von Willebrand factor, and platelet adhesion was measured. We also measured Fibrinogen adsorption to the surfaces from plasma, monoclonal antibody binding to Adsorbed Fibrinogen and SDS elutability of the Adsorbed Fibrinogen. The antibodies used bind to the three putative platelet binding sites on Fibrinogen, namely, M1 antibody binds to the dodecapeptide at the C-terminus of the gamma chain, γ (402–411), R1 antibody binds to a sequence in the Aα chain (87–100) which includes RGDF ...
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Variations in the ability of Adsorbed Fibrinogen to mediate platelet adhesion to polystyrene-based materials: A multivariate statistical analysis of antibody binding to the platelet binding sites of Fibrinogen
Journal of biomedical materials research. Part A, 2003Co-Authors: Wei-bor Tsai, J. M. Grunkemeier, Thomas A. HorbettAbstract:Platelet adhesion to the surfaces of biomaterials preAdsorbed with plasma previously has been shown to be mediated exclusively by surface-bound Fibrinogen and does not seem to involve the other adhesion proteins in plasma (Tsai et al., J Biomed Mater Res 2002;60:348–359). In this study, the influence of surface-bound Fibrinogen on platelet adhesion to five different types of polystyrene-based microtiter plates preAdsorbed with plasma was analyzed relative to the amount of Adsorbed Fibrinogen and monoclonal antibody binding to the Adsorbed Fibrinogen. There was no significant correlation between platelet adhesion and the absolute amount of Adsorbed Fibrinogen. However, platelet adhesion was positively correlated to the ability of the Adsorbed Fibrinogen to bind three types of monoclonal antibodies. The antibodies used bound to the sites on Fibrinogen thought to be involved in platelet binding (the two γ chain C-terminal dodecapeptides and the RGDF and RGDS sequences in each of the Aα chains). A partial least-squares calibration model was used to analyze the relative importance of these binding sites in Fibrinogen to platelet adhesion. The γ chain C-terminal dodecapeptide was shown to be the most important site in Adsorbed Fibrinogen in mediating platelet adhesion. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 1255–1268, 2003
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Co-Adsorbed Fibrinogen and von Willebrand factor augment platelet procoagulant activity and spreading.
Journal of Biomaterials Science Polymer Edition, 2001Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, Thomas A. HorbettAbstract:Previously we observed that platelets adherent to surfaces preAdsorbed with blood plasma exhibited 1.3 to 2.4 times greater procoagulant activity than platelets on surfaces Adsorbed with Fibrinogen (Fg) only. These observations suggested that the adhesion proteins Adsorbed from plasma may activate platelets in a cooperative, or synergistic manner. In the present study, polystyrene surfaces Adsorbed with both Fg and vWF induced up to three times greater procoagulant activity than surfaces Adsorbed with Fg or vWF only. The amounts of Fg and vWF Adsorbed from binary mixtures that resulted in increased procoagulant activity were found to be similar to the amounts that Adsorbed to PS from 100% plasma. The effect of Adsorbed adhesion proteins on platelet spreading was also investigated. The proportion of fully spread platelets increased, depending on the adhesion protein preAdsorbed to the surface, in the following order: vWF < Fg < Fn < (vWF + Fg) < Vn < plasma.
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the effect of Adsorbed Fibrinogen fibronectin von willebrand factor and vitronectin on the procoagulant state of adherent platelets
Biomaterials, 2000Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, Clive D. Mcfarland, Thomas A. HorbettAbstract:Procoagulant (activated) platelets provide a site for assembly of the prothrombinase complex which can rapidly convert prothrombin into thrombin (a potent inducer of clot formation). Previously, we reported that adhesion of platelets to surfaces preAdsorbed with blood plasma caused them to become procoagulant. In the present study we investigated the effect of Adsorbed adhesion proteins (Fibrinogen (Fg), fibronectin (Fn), von Willebrand factor (vWF) and vitronectin (Vn)) on the procoagulant activity of adherent platelets. Adsorbed Fn, vWF and Fg promoted platelet adhesion in the following order: Fn
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Platelet adhesion and procoagulant activity induced by contact with radiofrequency glow discharge polymers: roles of Adsorbed Fibrinogen and vWF.
Journal of Biomedical Materials Research, 2000Co-Authors: J. M. Grunkemeier, Wei-bor Tsai, David G. Castner, Morgan R. Alexander, Thomas A. HorbettAbstract:The potential hemocompatibility of radiofrequency glow discharge (RFGD) polymers made by copolymerization of mixtures of hexafluoropropene and ethylene (C3F6/C2H4) or acrylic acid and 1,7-octadiene was investigated using in vitro assays for platelet adhesion and platelet catalyzed thrombin generation. Thrombin generation rate normalized to platelet number was used as a measurement of platelet activation (procoagulant activity). RFGD polymers produced by copolymerization of acrylic acid and 1,7-octadiene contained varying amounts of carboxylic acid species as determined by electron spectroscopy for chemical analysis (ESCA). These polymers induced little variation in platelet adhesion, thrombin generation, or platelet activation. RFGD polymerization of C3F6 and C2H4 resulted in polymers with varying proportions of fluorinated species, as determined by ESCA. Fibrinogen adsorption from plasma was maximal on a polymer made with 25% C3F6 (75% C2H4) in the feed. However von Willebrand factor (vWF) adsorption was greater on polymers made with increased %C3F6 in the feed. Platelet adhesion decreased with increasing %C3F6 in the feed. Thrombin generation was lowest for platelets adherent to polymers made from both C3F6 and C2H4. Therefore, procoagulant activity of platelets increased for polymers made with increased %C3F6 in the feed, similar to the trend in vWF adsorption. These findings suggest that increased incorporation of fluorinated species into RFGD polymers leads to decreased platelet adhesion and increased platelet activation (which is possibly due to increased vWF adsorption). © 2000 John Wiley & Sons, Inc. J Biomed Mater Res, 51, 669–679, 2000.
