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Feijen J. The triangle, in memory of Prof. Sung Wan Kim. J Control Release 2020; 328:962-969. [PMID: 33022329 DOI: 10.1016/j.jconrel.2020.09.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 09/28/2020] [Indexed: 10/23/2022]
Affiliation(s)
- Jan Feijen
- Department of Polymer Chemistry and Biomaterials, TechMed Centre, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, the Netherlands..
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Anderson JM, Grainger DW. Sung Wan Kim - Early events in blood/material interactions. J Control Release 2020; 330:31-35. [PMID: 33212119 DOI: 10.1016/j.jconrel.2020.11.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 11/24/2022]
Abstract
Sung Wan Kim's initial efforts as an independent investigator were focused on improving the understanding of the early events in blood/material interactions with the goal to develop blood compatible materials for application in medical devices and prostheses. These initial efforts were centered around blood protein adsorption on biomaterials and related mechanisms of thrombus formation (thrombosis). Ultimately, Sung Wan's efforts were expanded to studies of the non-thrombogenic nature of heparinized biomaterials, prostaglandin biomaterials, and block copolymer systems. These studies were supported by two NIH grants for 22 and 19 years, respectively, and a NIH Career Development Award. Moreover, these studies resulted in over 140 peer-reviewed publications and training of many students and postdoctoral scientists. The intent of this paper is to identify key concepts, papers, and contributions by Sung Wan and his colleagues that fall within the four aforementioned research categories. In this context, many of Sung Wan's early efforts contributed directly to Utah's biomaterials efforts and the Total Artificial Heart program at the time, while providing the foundation for the productive international Triangle Collaboration as well as his following work in polymer-controlled drug releasing systems.
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Affiliation(s)
- James M Anderson
- Department of Pathology, Case Western Reserve University, Wolstein Bldg. Rm 5-105, 2103 Cornell Road, Cleveland, OH 44106, USA.
| | - David W Grainger
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA; Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA
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3
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Aslani S, Kabiri M, HosseinZadeh S, Hanaee-Ahvaz H, Taherzadeh ES, Soleimani M. The applications of heparin in vascular tissue engineering. Microvasc Res 2020; 131:104027. [DOI: 10.1016/j.mvr.2020.104027] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 06/01/2020] [Accepted: 06/02/2020] [Indexed: 02/06/2023]
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4
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Engbers G, Feijen J. Current Techniques to Improve the Blood Compatibility of Biomaterial Surfaces. Int J Artif Organs 2018. [DOI: 10.1177/039139889101400403] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- G.H. Engbers
- University of Twente, Department of Chemical Technology, section of Biomedical Materials Technology, Enschede
- Holland Biomaterials Group bv, Enschede – The Netherlands
| | - J. Feijen
- University of Twente, Department of Chemical Technology, section of Biomedical Materials Technology, Enschede
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Affiliation(s)
- Li-Chien Hsu
- Bentley Laboratories Division, Baxter Healthcare Corporation, Irvine, California
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Zhong Z. Professor Jan Feijen: A pioneer in biomedical polymers and controlled drug release. J Control Release 2015; 205:3-6. [DOI: 10.1016/j.jconrel.2015.03.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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7
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Gore S, Andersson J, Biran R, Underwood C, Riesenfeld J. Heparin surfaces: Impact of immobilization chemistry on hemocompatibility and protein adsorption. J Biomed Mater Res B Appl Biomater 2014; 102:1817-24. [DOI: 10.1002/jbm.b.33154] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 02/25/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Savannah Gore
- W.L. Gore & Associates; 4100 W Kiltie Lane Flagstaff Arizona 86005
| | | | - Roy Biran
- W.L. Gore & Associates; 4100 W Kiltie Lane Flagstaff Arizona 86005
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8
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Sakiyama-Elbert SE. Incorporation of heparin into biomaterials. Acta Biomater 2014; 10:1581-7. [PMID: 24021232 DOI: 10.1016/j.actbio.2013.08.045] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 08/27/2013] [Accepted: 08/29/2013] [Indexed: 11/30/2022]
Abstract
This review provides an overview of the incorporation of heparin into biomaterials with a focus on drug delivery and the use of heparin-based biomaterials for self-assembly of polymer networks. Heparin conjugation to biomaterials was originally explored to reduce the thrombogenicity of materials in contact with blood. Many of the conjugation strategies that were developed for these applications are still popular today for other applications. More recently heparin has been conjugated to biomaterials for drug delivery applications. Many of the delivery approaches have taken advantage of the ability of heparin to bind to a wide variety of growth factors, protecting them from degradation and potentiating interactions with cell surface receptors. More recently, the use of heparin as a base polymer for scaffold fabrication has also been explored, often utilizing non-covalent binding of heparin with peptides or proteins to promote self-assembly of hydrogel networks. This review will highlight recent advances in each of these areas.
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Affiliation(s)
- Shelly E Sakiyama-Elbert
- Department of Biomedical Engineering, Washington University, 1 Brookings Drive, Campus Box 1097, St Louis, MO 63130, USA.
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Sideek MA, Menz C, Parsi MK, Gibson MA. LTBP-2 competes with tropoelastin for binding to fibulin-5 and heparin, and is a negative modulator of elastinogenesis. Matrix Biol 2013; 34:114-23. [PMID: 24148803 DOI: 10.1016/j.matbio.2013.10.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 09/30/2013] [Accepted: 10/15/2013] [Indexed: 01/08/2023]
Abstract
Latent transforming growth factor-beta-1 binding protein-2 (LTBP-2) is a protein of ill-defined function associated with elastic fibers during elastinogenesis. Although LTBP-2 binds fibrillin-1, fibulin-5, and heparin/heparan sulfate, molecules critical for normal elastic fiber assembly, it does not interact directly with elastin or its precursor, tropoelastin. We investigated the modulating effect of LTBP-2 on two key interactions of tropoelastin during elastinogenesis a) with fibulin-5 and b) with heparan sulfate (using heparin). Firstly, using solid phase assays we showed that LTBP-2 bound fibulin-5 (Kd=26.47±5.68 nM) with an affinity similar to that of the tropoelastin-fibulin-5 interaction (Kd=24.66±5.64 nM). Then using a competitive binding assay we showed that LTBP-2 inhibited the tropoelastin-fibulin-5 interaction in a dose dependent manner with almost complete inhibition obtained with 5-fold molar excess of LTBP-2. Interestingly, a fragment of LTBP-2 containing the fibulin-5 binding sequence only partially inhibited the tropoelasin-fibulin-5 interaction suggesting that LTBP-2 was directly blocking only the C-terminal tropoelastin binding site on fibulin-5 and indirectly blocking tropoelastin binding to the N-terminal region. In parallel experiments heparin was shown to have minor inhibitory effects on fibulin-5 interactions with tropoelastin and LTBP-2. However, LTBP-2 was shown to significantly inhibit the binding of heparin to tropoelastin with 50% inhibition achieved with 10 fold molar excess of LTBP-2. Confocal microscopy of fibroblast matrix showed strong co-distribution of LTBP-2 with fibulin-5 and fibrillin-1 and partial co-distribution with heparan sulfate proteoglycans, perlecan and syndecan-4. Also addition of exogenous LTBP-2 to ear cartilage chondrocyte cultures blocked elastinogenesis in a concentration-dependent manner. Overall the results indicate that LTBP-2 may have a negative regulatory role during elastic fiber assembly, perhaps in displacing elastin microassemblies from complexes with fibulin-5 and/or cell surface heparan sulfate proteoglycans.
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Affiliation(s)
- Mohamed A Sideek
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Clementine Menz
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Mahroo K Parsi
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Mark A Gibson
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
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Ponedel’kina IY, Lukina ES, Odinokov VN. Acid glycosaminoglycans and their chemical modification. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2011. [DOI: 10.1134/s1068162008010019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Parsi MK, Adams JR, Whitelock J, Gibson MA. LTBP-2 has multiple heparin/heparan sulfate binding sites. Matrix Biol 2010; 29:393-401. [DOI: 10.1016/j.matbio.2010.03.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 03/26/2010] [Accepted: 03/26/2010] [Indexed: 11/28/2022]
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12
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Duo J, Fletcher H, Stenken JA. Natural and synthetic affinity agents as microdialysis sampling mass transport enhancers: current progress and future perspectives. Biosens Bioelectron 2006; 22:449-57. [PMID: 16797961 DOI: 10.1016/j.bios.2006.05.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Revised: 02/15/2006] [Accepted: 05/03/2006] [Indexed: 10/24/2022]
Abstract
Microdialysis sampling is a diffusion-based separation method that allows analytes to freely diffuse across a hollow fiber semi-permeable dialysis membrane. This sampling technique has been widely used for in vivo chemical collection. The inclusion of affinity-based trapping agents into the microdialysis perfusion fluid serves to improve the relative recovery via the binding reaction of low molecular weight hydrophobic analytes and larger analytes such as peptides and proteins. Here, we briefly review our past studies using different compounds (native cyclodextrins and antibodies) to improve microdialysis sampling recovery. A brief compilation of our studies using antibody-immobilized beads as a means to improve cytokine collection during microdialysis sampling is also described. We present new work focused on the use of antibody-immobilized bead microdialysis sampling enhancement for various endocrine hormones (amylin, GLP-1, glucagon, insulin, and leptin). The antibody-bead enhancement approach allowed for recovery enhancements that ranged between 3 and 20-fold for these peptides. Using the enhanced recovery approach, endocrine peptides at pM concentrations can be quantified. Finally, our initial work focused on developing non-antibody based enhancement agents using bovine serum albumin-heparin conjugates covalently bound to polystyrene microspheres is presented for the cytokine, tumor necrosis factor-alpha (TNF-alpha). Unlike antibodies, heparin provides the advantage of being reusable as an enhancement agent and served to improve the relative recovery of TNF-alpha by three-fold.
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Affiliation(s)
- Jia Duo
- Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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Zhang F, Ronca F, Linhardt RJ, Margolis RU. Structural determinants of heparan sulfate interactions with Slit proteins. Biochem Biophys Res Commun 2004; 317:352-7. [PMID: 15063764 DOI: 10.1016/j.bbrc.2004.03.059] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Indexed: 10/26/2022]
Abstract
We have previously demonstrated that the Slit proteins, which are involved in axonal guidance and related processes, are high-affinity ligands of the heparan sulfate proteoglycan glypican-1. Glypican-Slit protein interactions have now been characterized in greater detail using two approaches. The ability of heparin oligosaccharides of defined structure (ranging in size from disaccharide to tetradeccasaccharide) to inhibit binding of a glypican-Fc fusion protein to recombinant human Slit-2 was determined using an ELISA. Surface plasmon resonance (SPR) spectroscopy, which measures the interactions in real time, was applied for quantitative modeling of heparin-Slit binding on heparin biochips. Heparin was covalently immobilized on these chips through a pre-formed albumin-heparin conjugate, and the inhibition of Slit binding by heparin, LMW heparin, and heparin-derived oligosaccharides (di-, tetra-, hexa-, and octa-) was examined utilizing solution competition SPR. These competition studies demonstrate that the smallest heparin oligosaccharide competing with heparin binding to Slit was a tetrasaccharide, and that in the ELISA maximum inhibition (approximately 60% at 2 microM concentration) was attained with a dodecasaccharide.
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Affiliation(s)
- Fuming Zhang
- Departments of Chemistry, Biology, and Chemical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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Kim TK, Burgess DJ. Formulation and release characteristics of poly(lactic-co-glycolic acid) microspheres containing chemically modified protein. J Pharm Pharmacol 2001; 53:23-31. [PMID: 11206188 DOI: 10.1211/0022357011775154] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Chemical modification of proteins may influence their formulation into and release from polymeric microspheres. Three chemical modifications of rat serum albumin (RSA) were effected on the amine groups of this protein: conjugation with a polyanion using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, intermolecular cross-linking using glutaraldehyde, and reductive alkylation using propyl aldehyde. The modified proteins had different physicochemical properties as well as improved encapsulation efficiencies compared with native RSA microspheres. The microspheres were incubated at 37 degrees C for over one month to investigate the influence of protein modification on the release profiles. Microsphere degradation accelerated from the ninth day of the release studies and this coincided with an increase in the release rates. The degradation rates of poly(lactic-co-glycolic acid) microspheres containing either native or cross-linked RSA were more rapid than those containing either heparin conjugated or propylated RSA. This was in agreement with the release data, since the release of the native and cross-linked RSA were more rapid than those of the other modified proteins. The release profiles of the RSA-heparin conjugates and the propylated RSA were approximately zero rather than first order between the tenth and thirtieth day of study. Chemical modification of protein may be a useful method to increase encapsulation efficiency and to decrease release rates of proteins that are to be used in microsphere formulations of potent therapeutic proteins.
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Affiliation(s)
- T K Kim
- School of Pharmacy, University of Connecticut, Storrs 06269, USA
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16
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Phaneuf MD, Szycher M, Berceli SA, Dempsey DJ, Quist WC, LoGerfo FW. Covalent linkage of recombinant hirudin to a novel ionic poly(carbonate) urethane polymer with protein binding sites: determination of surface antithrombin activity. Artif Organs 1998; 22:657-65. [PMID: 9702317 DOI: 10.1046/j.1525-1594.1998.05091.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Surface thrombus formation on implantable biomaterials such as polyurethane is a major concern when utilizing these materials in the clinical setting. Thrombin, which is responsible for thrombus formation and smooth muscle cell activation, has been the target of numerous surface modification strategies in an effort to prevent this phenomenon from occurring. The purpose of this study was to covalently immobilize the potent, specific antithrombin agent recombinant hirudin (rHir) onto a novel polyurethane polymer synthesized with carboxylic acid groups which served as protein attachment sites. The in vitro efficacy of thrombin inhibition by this novel biomaterial surface was then evaluated. Bovine serum albumin (BSA), which was selected as the basecoat protein, was reacted with sulfo-SMCC in a 1:50 molar ratio. This BSA-SMCC complex was then covalently linked to the carboxylated polyurethane (cPU) surface via the crosslinker EDU (cPU-BSA-SMCC). This cPU-BSA-SMCC surface was then reacted with Traut's-modified 125I-rHir, a procedure which created free sulfhydryl groups on rHir (cPU-BSA-SMCC-S-125I-rHir). Using these crosslinking procedures, the cPU-BSA-SMCC-S-125I-rHir segments bound 188 +/- 40 ng/cm2 (n = 60) whereas the controls with non-specifically bound 125I-rHir (Mitrathane + EDC + BSA + 125I-rHir-SH and cPU-BSA + 125I-rHir-SH) bound 13 +/- 8 ng/cm2 and 4 +/- 8 ng/cm2, respectively. Evaluation of these cPU-BSA-SMCC-S-125I-rHir segments for 131I-thrombin inhibition using a chromogenic assay for thrombin showed that a maximum of 2.64 NIHU thrombin was inhibited in contrast to the controls which inhibited bound 0.76 and 0.70 NIHU. Controls with nonspecifically bound 125I-rHir also had 0.31 and 0.76 NIHU 131I-thrombin adherent to their respective surfaces whereas the maximum 131I-thrombin binding to the cPU-BSA-SMCC-S-rHir segments was 1.51 NIHU. Exposure to 131I-thrombin did not result in any release of covalently bound 125I-rHir from the cPU-BSA-SMCC-S-125I-rHir segments. Thus, these results demonstrate that rHir can be covalently bound to this novel polyurethane surface and still maintain potent antithrombin activity.
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Affiliation(s)
- M D Phaneuf
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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Phaneuf MD, Quist WC, LoGerfo FW, Szycher M, Dempsey DJ, Bide MJ. Chemical and physical characterization of a novel poly(carbonate urea) urethane surface with protein crosslinker sites. J Biomater Appl 1997; 12:100-20. [PMID: 9399137 DOI: 10.1177/088532829701200202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A major complication which occurs with implantable polyurethane biomaterials is bioincompatibility between blood and the biomaterial surface. Development of a novel biodurable polyurethane surface to which biological agents, such as growth factors or anticoagulants could be covalently bound, would be beneficial. The purpose of this study was to synthesize a novel poly(carbonate urea) urethane polymer with carboxylic acid groups which would serve as "anchor" sites for protein attachment. Physical characteristics such as tensile strength, initial modulus, ultimate elongation, tear strength, water/alcohol uptake and water vapor permeation were then evaluated and compared to other biomedical-grade polyurethanes. Covalent linkage of the blood protein albumin to this novel surface was then examined. A biodurable polycarbonate-based polyurethane containing carboxylic acid groups (cPU) was synthesized using a two step procedure incorporating the chain extender 2,2-bis(hydroxymethyl)-propionic acid (DHMPA). Tensile strength of this cPU film was 2.7 and 2.6 fold greater than both a polycarbonate-based polyurethane synthesized with a 1,4-butanediol chain extender (bdPU) and Mitrathane (Mit) controls, respectively. The cPU polymer also possessed 7.8 and 31 fold greater structural rigidity upon evaluation of initial modulus as compared to the bdPU and Mit, respectively. Ultimate elongation for the bdPU films was slightly higher than the cPU and Mit films, which had comparable elongation properties. The force required to tear the bdPU film was 1.9 and 32 fold greater than the cPU and Mit films, respectively. Alcohol solution uptake by all of the polyurethane segments increased with increasing alcohol concentrations, with the cPU having the greatest uptake. Water uptake was minimal for all the polyurethanes examined and was not affected by altering pH. Water vapor permeation was lowest for the cPU films as compared to both bdPU and Mit. Swelling the cPU in 50% ethanol prior to evaluation slightly increased water vapor permeation through the films. Covalent linkage of the radiolabelled blood protein albumin (125I-BSA) to the cPU segments incubated with the heterobifunctional crosslinker 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) was greatest in the higher percent of ethanol as compared to controls. These results serve as foundation for developing a novel poly(carbonate urea) urethane with physical characteristics comparable to other medical-grade polyurethanes while having protein binding capabilities.
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Affiliation(s)
- M D Phaneuf
- Beth Israel Deaconess Medical Center/Harvard Medical School, Department of Surgery, Boston, MA 02115, USA
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Phaneuf MD, Berceli SA, Bide MJ, Quist WC, LoGerfo FW. Covalent linkage of recombinant hirudin to poly(ethylene terephthalate) (Dacron): creation of a novel antithrombin surface. Biomaterials 1997; 18:755-65. [PMID: 9158859 DOI: 10.1016/s0142-9612(96)00193-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Thrombus formation and intimal hyperplasia on the surface of implantable biomaterials such as poly(ethylene terepthalate) (Dacron) vascular grafts are major concerns when utilizing these materials in the clinical setting. Thrombin, a pivotal enzyme in the blood coagulation cascade primarily responsible for thrombus formation and smooth muscle cell activation, has been the target of numerous strategies to prevent this phenomenon from occurring. The purpose of this study was to covalently immobilize the potent, specific antithrombin agent recombinant hirudin (rHir) to a modified Dacron surface and characterize the in vitro efficacy of thrombin inhibition by this novel biomaterial surface. Bovine serum albumin (BSA), which was selected as the "basecoat' protein, was reacted with various molar ratios of the cross-linker sulphosuccinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate (sulpho-SMCC; 1:5-1:50). These BSA-SMCC complexes were then covalently linked to sodium hydroxide-hydrolysed Dacron (HD) segments via the cross-linker 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC). Covalent linkage of these complexes to HD (HD-BSA-SMCC) was not affected by any of the sulpho-SMCC cross-linker ratios assayed. rHir, which was initially reacted with 2-iminothiolane hydrochloride (Traut's reagent) in order to create sulphydryl groups, was then covalently bound to these HD-BSA-SMCC surfaces (HD-BSA-SMCC-S-rHir). The 1:50 (BSA: sulpho-SMCC) HD-BSA-SMCC-S-rHir segments bound 22-fold more rHir (111 ng per mg Dacron) compared to control segments and also possessed the greatest thrombin inhibition of the segments evaluated using a chromogenic substrate assay for thrombin. Further characterization of the HD-BSA-SMCC-S-rHir segments demonstrated that maximum thrombin inhibition was 20.43 NIHU, 14.6-fold greater inhibition than control segments (1.4 NIHU). Thrombin inhibition results were confirmed by 125I-thrombin binding experiments, which demonstrated that the 1:50 HD-BSA-SMCC-S-rHir segments had significantly greater specific thrombin adhesion compared to control segments. Non-specific 125I-thrombin binding to and release from the 1:50 HD-BSA-SMCC-S-rHir segments was also significantly less than the control segments. Thus, these results demonstrate that rHir can be covalently bound to a clinically utilized biomaterial (Dacron) while still maintaining its ability to bind and inhibit thrombin.
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Affiliation(s)
- M D Phaneuf
- Deaconess Hospital/Harvard Medical School, Vascular Surgery Research, Boston, MA 02215, USA
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Interactions of Proteins with Polyelectrolytes at Solid/Liquid Interfaces: Sequential Adsorption of Albumin and Heparin. J Colloid Interface Sci 1997. [DOI: 10.1006/jcis.1996.4576] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Denizli A, Pişkin E. Heparin-immobilized polyhydroxyethylmethacrylate microbeads for cholesterol removal: a preliminary report. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1995; 670:157-61. [PMID: 7493074 DOI: 10.1016/0378-4347(95)00144-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Heparin-attached polyhydroxyethylmethacrylate (PHEMA) microbeads were investigated for specific removal of cholesterol from human and rabbit plasma. PHEMA microbeads were prepared by a suspension polymerization technique and activated by cyanogen bromide (CNBr) in an alkaline medium (pH 11.5). Heparin was then immobilized by covalent binding onto these microbeads. Cholesterol adsorption onto PHEMA microbeads containing two different amounts of immobilized heparin, i.e., 57.3 and 122.7 mg/g, from both hypercholesterolaemic human and rabbit plasma was investigated. The non-specific cholesterol adsorptions on the plain PHEMA microbeads were 0.47 mg/g and 0.30 mg/g from human and rabbit plasmas, respectively. About 35% and 32% of the cholesterol was removed from human and rabbit plasmas, respectively, when the heparin-immobilized PHEMA microbeads were used.
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Affiliation(s)
- A Denizli
- Hacettepe University, Chemical Engineering Department, Ankara, Turkey
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Pizzoferrato A, Arciola CR, Cenni E, Ciapetti G, Sassi S. In vitro biocompatibility of a polyurethane catheter after deposition of fluorinated film. Biomaterials 1995; 16:361-7. [PMID: 7662821 DOI: 10.1016/0142-9612(95)93853-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The in vitro biocompatibility of an experimental surface-treated polyurethane was compared with an untreated polyurethane already used for intravascular catheters. The experimental surface was coated with a fluorinated film using a glow discharge treatment. Neither of the catheters was cytotoxic for L929 murine fibroblasts, caused platelet adhesion or release reaction, or changed the mean platelet volume. The surface-treated polyurethane, however, caused a higher adhesion of Staphylococcus aureus than did the untreated one. Therefore, using in vitro testing, it has been ascertained that the examined material, though not being cytotoxic and not modifying platelet behaviour, could favour bacterial adherence.
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Affiliation(s)
- A Pizzoferrato
- Laboratory for Biocompatibility Research on Implant Materials, Istituti Ortopedici Rizzoli, Bologna, Italy
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Abstract
It has been shown repeatedly in animal and clinical studies that heparin coating reduces thrombotic complications of several surfaces in contact with flowing blood. The demonstration that implantation of heparin-coated coronary stents is also effective in prevention of subacute thrombotic occlusion in a pig model offers the perspective of a clinical role of this treatment too. In order to put this to the test, the Benestent II pilot trial has been designed. This study will be conducted in a stepwise fashion in order to explore the feasibility of delaying deep anticoagulation as much as possible. Therefore, the primary goal is to minimize or exclude the need for heparin treatment following stent implantation. In addition, the effects on the need for revascularization procedures during follow-up will be recorded as well as the late morphological consequences as measured with quantitative coronary angiography.
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Affiliation(s)
- H Emanuelsson
- Division of Cardiology, Sahlgrenska University Hospital, Göteborg, Sweden
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Cremers HF, Wolf RF, Blaauw EH, Schakenraad JM, Lam KH, Nieuwenhuis P, Verrijk R, Kwon G, Bae YH, Kim SW. Degradation and intrahepatic compatibility of albumin-heparin conjugate microspheres. Biomaterials 1994; 15:577-85. [PMID: 7948576 DOI: 10.1016/0142-9612(94)90207-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The in vitro degradation properties of glutaraldehyde cross-linked albumin and albumin-heparin conjugate microspheres (AMS and AHCMS respectively) were evaluated using light microscopy, turbidity measurements and heparin release determinations, showing that the microspheres are degraded by proteolytic enzymes such as trypsin, proteinase K and lysosomal enzymes. The degradation rate was inversely related to the cross-link density of the microspheres. After intrahepatic administration of AHCMS, cross-linked with 0.5% glutaraldehyde, to male Wag/Rij rats by injection into a mesenteric vein (intravenoportal: i.v.p.), the microspheres were entrapped in the hepatic vascular system. The AHCMS were entrapped within terminal portal veins predominantly at the periphery of the liver. The AHCMS were degraded by cellular enzymatic processes within 2 wk after injection, with a half life of approximately 1 d. Biocompatibility of AHCMS and adriamycin-loaded AHCMS was evaluated by histological assessment of the mitotic activity of liver parenchyma and inflammatory response, and by determination of liver damage marker enzymes during 4 wk after administration. Liver damage marker enzymes were not increased compared with controls, nor were adverse effects observed upon histological examination. There was no difference in response between empty and adriamycin-loaded AHCMS.
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Affiliation(s)
- H F Cremers
- Department of Chemical Technology, University of Twente, Enschede, The Netherlands
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Cremers H, Verrijk R, Noteborn H, Kwon G, Bae Y, Kim S, Feijen J. Adriamycin loading and release characteristics of albumin-heparin conjugate microspheres. J Control Release 1994. [DOI: 10.1016/0168-3659(94)90130-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Cremers HF, Kwon G, Bae YH, Kim SW, Verrijk R, Noteborn HP, Feijen J. Preparation and characterization of albumin-heparin microspheres. Biomaterials 1994; 15:38-48. [PMID: 8161656 DOI: 10.1016/0142-9612(94)90195-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Albumin-heparin microspheres were prepared by a two-step process which involved the preparation of a soluble albumin-heparin conjugate, followed by formation of microspheres from this conjugate or by a double cross-linking technique involving both coupling of soluble albumin and heparin and microsphere stabilization in one step. The first technique was superior since it allowed better control over the composition and the homogeneity of the microspheres. Microspheres could be prepared with a diameter of 5-35 microns. The size could be controlled by adjusting the emulsification conditions. The degree of swelling of the microspheres was sensitive to external stimuli, and increased with increasing pH and decreasing ionic strength of the medium.
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Affiliation(s)
- H F Cremers
- Department of Chemical Technology, University of Twente, Enschede, The Netherlands
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Kwon GS, You Han Bae, Cremers H, Feijen J, Sung Wan Kim. Release of macromolecules from albumin-heparin microspheres. Int J Pharm 1992. [DOI: 10.1016/0378-5173(92)90110-n] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kwon GS, Bae YH, Kim SW, Cremers H, Feijen J. Preparation and characterization of microspheres of albumin-heparin conjugates. J Colloid Interface Sci 1991. [DOI: 10.1016/0021-9797(91)90283-e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Spears JR, Kundu SK, McMath LP. Laser balloon angioplasty: potential for reduction of the thrombogenicity of the injured arterial wall and for local application of bioprotective materials. J Am Coll Cardiol 1991; 17:179B-188B. [PMID: 2016476 DOI: 10.1016/0735-1097(91)90956-a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mitigation of adverse biologic reactivity after balloon angioplasty is necessary before the incidence of restenosis can be appreciably reduced. A brief review of experimental evidence supports the hypothesis that the thrombogenicity of the injured arterial wall can be reduced by a suitable level of thermal denaturation or cross-linking of thrombogenic proteins. In addition, the concept of local pharmacologic therapy, which can be provided with laser balloon angioplasty at the site of arterial injury, is introduced. Preliminary in vitro and in vivo data suggest that guide catheter-injected albumin-heparin conjugates fabricated as water-insoluble microspheres remain adherent to the injured luminal surface and deeper arterial layers after physical trapping by the inflated balloon and subsequent laser/thermal exposure. The combination of initially adequate luminal morphology, reduction of the thrombogenicity of the injured arterial wall and application of local pharmacologic therapy with laser balloon angioplasty may eventually prove helpful in reducing the incidence of restenosis.
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Affiliation(s)
- J R Spears
- Department of Medicine, Harper Hospital/Wayne State University, Detroit, Michigan
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Jacobs HA, Okano T, Kim SW. Antithrombogenic surfaces: characterization and bioactivity of surface immobilized PGE1-heparin conjugate. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1989; 23:611-30. [PMID: 2738078 DOI: 10.1002/jbm.820230606] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A covalently bonded conjugate of commercial grade heparin and prostaglandin E1 (PGE1) was synthesized to prevent both fibrin formation and platelet aggregation during thrombus formation. The PGE1-heparin conjugate was immobilized on an imidazole carbamate derivatized sepharose bead surface through hydrophilic spacer groups (diamino-terminated polyethylene oxides). One end of the spacer group was coupled to the derivatized surface through a urethane bond between the amine group of the spacer and the derivatized surface. The free amine group of the immobilized spacers was coupled to a carboxylic group of the PGE1-heparin conjugate through an amide bond. Bioactivity of the immobilized conjugate (heparin activity) was measured in terms of increased clotting times (thrombin time assay) and for the inactivation of Factor Xa. Bioactivity of the immobilized compound (PGE1 activity) was analyzed by platelet adhesion and platelet release reactions using C14-5-hydroxytryptamine (5-HT). The conjugate immobilized via the C2 spacer showed the highest incidence of platelet adhesion, 5-HT released and the lowest activity for coagulation factors. In contrast, the 1000 and 4000 immobilized systems showed a significant reduction in platelet activation, while having the greatest effect on coagulation factors. The results of these experiments imply that the immobilized conjugate is active in preventing both pathways of thrombus formation, and the efficacy is improved through the use of long-chain hydrophilic spacer groups.
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Affiliation(s)
- H A Jacobs
- Department of Pharmaceutics, University of Utah, Salt Lake City 84108
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Chandy T, Sharma CP. The preparation of a urokinase-AT-III-PGE1-methyldopa complex, and its effects on platelet adhesion, coagulation times, protein adsorption, and fibrinolysis. Artif Organs 1989; 13:229-37. [PMID: 2764762 DOI: 10.1111/j.1525-1594.1989.tb02868.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Modifications of urokinase by substances possessing useful therapeutic activity permit combined action preparations to be obtained. Here an attempt was made to develop a complex having combined action for therapeutic activity. The possibility of repeatedly modified urokinase with antithrombin-III-methyldopa-prostaglandin E1 had been experimentally demonstrated. The complex was immobilized on albuminated substrate, which showed fibrinolytic, anticoagulant, and antiplatelet effects simultaneously, in addition to the normal antihypertensive action of methyldopa. The complex immobilized substrate also demonstrated an increase in albumin-surface attachment and a reduction in fibrinogen binding. This may be one of the parameters for a reduced platelet-surface attachment, which may also improve the blood compatibility of the substrate. The approaches suggested indicate the possible new ways of creating nonthrombogenic surfaces with wider applications. A better understanding of the mechanism of these complexes are needed in in vivo conditions to correlate these findings.
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Affiliation(s)
- T Chandy
- Biosurface Technology Division, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Trivandrum, India
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Pejler G, Lindahl U, Larm O, Scholander E, Sandgren E, Lundblad A. Monoclonal antibodies specific for oligosaccharides prepared by partial nitrous acid deamination of heparin. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)60699-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Grainger DW, Kim SW, Feijen J. Poly(dimethylsiloxane)-poly(ethylene oxide)-heparin block copolymers. I. Synthesis and characterization. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1988; 22:231-49. [PMID: 3360815 DOI: 10.1002/jbm.820220307] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Amphiphilic block copolymers containing poly(dimethylsiloxane), poly(ethylene oxide), and heparin (PDMS-PEO-Hep) have been prepared via a series of coupling reactions using functionalized prepolymers, diisocyanates, and derivatized heparins. All intermediate steps of the synthesis yield quantifiable products with reactive end-groups, while the final products demonstrate bioactive, covalently bound heparin moieties. Due to the solvent systems required, commercial sodium heparin was converted to its benzyltrimethyl ammonium salt to enhance its solubility. The same procedure was applied to heparin degraded by nitrous acid in order to covalently couple it in solutions with the semitelechelic copolymers. As might be expected, this derivatization reduces the apparent bioactivity of the heparin. However, preliminary findings suggest that the bioactivity can be restored by reforming the heparin sodium salt.
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Affiliation(s)
- D W Grainger
- Department of Pharmaceutics, University of Utah, Salt Lake City
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Affiliation(s)
- S W Kim
- Department of Pharmaceutics, University of Utah, Salt Lake City 84112
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Abstract
Many kinds of heparin-bound polyurethanes have been developed. Polyurethanes are a family of elastomers displaying better blood-compatibility than other polymeric materials. It is useful to modify this material by heparinization. Several approaches to heparinization have been devised: 1) a general method of heparinization, applicable to all polymeric materials, 2) a heparinization method specific to polyurethanes, and 3) the design of heparinizable polyurethane derivatives. These three approaches are first explained in detail. Then, the antithrombogenic mechanism of the heparinized polymers is discussed. Finally, the interactions of the heparinized polymers with blood coagulation factors, plasma proteins, and platelets are discussed.
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Affiliation(s)
- Y Ito
- Department of Polymer Chemistry, Faculty of Engineering, Kyoto University, Japan
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Abstract
It has been proposed that adsorbed glycoproteins such as fibrinogen and gamma-globulin induce platelet adhesion at blood-polymer interfaces. The importance of oligosaccharide groups in the glycoproteins proved to be responsible for platelet adhesion and aggregation via possible complex formation. Several studies have provided evidence that the proposed mechanism was involved in platelet adhesion on polymer surfaces. To minimize or prevent platelet adhesion on polymers, prostaglandins (PGs), potent inhibitors of platelet aggregation and PG-heparin (HEP) conjugate, were combined with polymers via physical dispersion or chemical immobilization on the surfaces. Albumin-HEP conjugate-adsorbed surfaces also showed significant reduction of platelet adhesion.
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Engbers GH, Dost L, Hennink WE, Aarts PA, Sixma JJ, Feijen J. An in vitro study of the adhesion of blood platelets onto vascular catheters. Part I. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1987; 21:613-27. [PMID: 3584166 DOI: 10.1002/jbm.820210507] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The adhesion of human blood platelets onto vascular catheters was studied using a specially designed perfusion chamber. Polyurethane catheters were exposed to citrated human blood for different periods (up to 20 min) and at different wall shear rates (190, 260, 330 sec-1). The rate of platelet adhesion was determined using 111In-labeled platelets, while the morphology of adhering platelets was investigated using scanning electron microscopy. A linear increase in platelet adhesion was found within the first 10 min of perfusion, after which a plateau value was reached. The number of adhering platelets did not vary significantly with the shear rates applied, which may indicate that within the range of shear rates studied, the adhesion of platelets onto the catheter surface is mainly determined by the rate of the reaction between the platelets and the material surface. Catheters coated with a conjugate of heparin and albumin showed a four- to five-fold reduction in platelet adhesion as compared to uncoated catheters. This reduction in platelet adhesion was not only due to the presence of albumin moieties at the surface but also to the presence of heparin residues in the adsorbed albumin-heparin conjugate.
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Abstract
A covalently bound conjugate of commercial grade heparin and prostaglandin E1 (PGE1) was synthesized to provide the dual pharmacological role of decreasing the extent of platelet aggregation and inhibiting fibrin formation during thrombogenesis. The compound was synthesized using a modified mixed carbonic anhydride method of amide bond formation between the carboxylic acid moiety of PGE1 and a primary amine group on heparin. Quantitation of coupling was measured spectrophotometrically by monitoring a degradation product of the prostaglandin E1-heparin conjugate (prostaglandin B1-heparin conjugate). Bioactivity tests on the conjugates (activated partial thromboplastin time and platelet aggregation) confirmed that both the anticoagulant activity of heparin and the inhibitory effect of PGE1 on platelet aggregation were maintained.
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Hennink WE, Klerx JP, van Dijk H, Feijen J. Complement inhibitory and anticoagulant activities of fractionated heparins. Thromb Res 1984; 36:281-92. [PMID: 6523441 DOI: 10.1016/0049-3848(84)90319-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Almost monodisperse heparin fractions (Mw/Mn less than 1.1) were obtained by gel filtration of a commercial heparin. These fractions were assayed for anticoagulant activity (thrombin times and APTT), chromogenic anti-factor Xa activity, inhibitory activity for the human classical complement pathway, carboxyl group content and total sulfate content. Linear relationships were observed between the molecular weight of the heparin fractions and the anti-coagulant activities as determined by thrombin time- and APTT-assay and the classical complement pathway inhibitory activity. On the other hand a hyperbolic-like relationship was observed between the molecular weight of the heparin fractions and the chromogenic anti-factor Xa activity. The heparin fractions did not show significant differences with respect to the carboxyl group and total sulfate content. Low- and high affinity heparin fractions were obtained by affinity chromatography using immobilized AT III. High- and low-affinity fractions greatly differed not only with respect to their APTT activity, but also where their complement-inhibitory activities were concerned. The latter in contrast to literature data available. These differences could not be explained by the observed differences in molecular weight of high and low affinity heparin respectively.
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Hennink WE, Kim SW, Feijen J. Inhibition of surface induced coagulation by preadsorption of albumin-heparin conjugates. ACTA ACUST UNITED AC 1984; 18:911-26. [PMID: 6544786 DOI: 10.1002/jbm.820180806] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Surface coatings of the albumin-heparin conjugates were developed to improve the blood compatibility of polymeric materials. Glass, PVC, Biomer and cellulose acetate were coated with albumin-heparin conjugate and its adsorption and desorption behavior on glass in particular was studied using 3H and 51Cr radiolabeled conjugates. Precoated materials showed a significant prolongation of the Lee-White clotting time as compared with noncoated ones. It was demonstrated that the prolonged clotting time for pretreated glass was due to surface bound conjugate. Prolonged recalcification times of plasma exposed to glass, Biomer, and PVC were obtained using albumin-heparin conjugate precoated surfaces. Albumin-heparin conjugates with high affinity for antithrombin III gave more prolonged clotting times as low affinity conjugates when used as coatings for glass. This indicates that the behaviour of heparin in preadsorbed conjugates resembles that of heparin in solution.
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Hennink WE, Ebert CD, Kim SW, Breemhaar W, Bantjes A, Feijen J. Interaction of antithrombin III with preadsorbed albumin-heparin conjugates. Biomaterials 1984; 5:264-8. [PMID: 6487709 DOI: 10.1016/0142-9612(84)90070-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The adsorption of antithrombin III (AT III) onto polystyrene surfaces preadsorbed with albumin or albumin-heparin conjugates was studied using a two step enzyme immuno assay. When AT III-buffer solutions were used, the highest adsorption values were measured on high affinity albumin-heparin conjugate pretreated surfaces. Less AT III adsorption was found on nonfractionated albumin-heparin conjugate preadsorbed surfaces. AT III adsorption could also be detected on low affinity conjugate and albumin coated surfaces. When AT III was adsorbed from plasma or plasma dilutions with buffer, only AT III on surfaces preadsorbed with high affinity or nonfractionated albumin-heparin conjugate was found. These results demonstrate that the heparin moiety of the conjugate is directed to the solution phase whereas the albumin moiety contacts the polystyrene surface.
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