title: Platelet Adhesion and Fibrinogen Accretion on a Family of Elastin-Like Polypeptides.
abstract: Previous work in our laboratory showed the potential of using a human recombinant elastin-like polypeptide (ELP) as a thromboresistant coating. In this work we investigate the use of three particular ELPs (ELP1, ELP2 and ELP4), that differ by molecular weight and number of repeating hydrophobic and cross-linking domains, as coatings to improve blood-contacting properties. All three ELPs were passively adsorbed on Mylar surfaces. Differences in water contact angle and surface concentration were found among the three ELP coatings, with the shortest polypeptide, ELP1, being the most hydrophilic and abundant on the surface (55°, 0.76 μg/cm(2)), followed by ELP2 (55°, 0.35 μg/cm(2)) and ELP4, the longest of the three (66°, 0.25 μg/cm(2)), respectively. The blood interactions of the ELP coatings were investigated by measuring fibrinogen adsorption and platelet adhesion in whole blood under laminar flow in a cone and plate viscometer configuration. In general, platelet adhesion to the ELP-coated surfaces was found to correlate with fibrinogen adsorption. Decreases in fibrinogen accretion and platelet adhesion were observed for ELP-coated compared to uncoated surfaces. The magnitude of the decreases was found to depend on the ELP sequence length, with ELP4 exhibiting the lowest levels of fibrinogen adsorption and platelet adhesion at 43 ± 24 ng/cm(2) and 113 ± 77 platelets/mm(2), respectively.
authors.affiliation: a Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
authors.forename: E M
authors.initials: EM
authors.lastname: Srokowski
authors.forename: P H
authors.initials: PH
authors.lastname: Blit
authors.forename: W G
authors.initials: WG
authors.lastname: McClung
authors.forename: J L
authors.initials: JL
authors.lastname: Brash
authors.forename: J P
authors.initials: JP
authors.lastname: Santerre
authors.forename: K A
authors.initials: KA
authors.lastname: Woodhouse
mesh_terms: D000327:Adsorption; D000595:Amino Acid Sequence; D001792:Blood Platelets / Q000502:physiology; D004549:Elastin / Q000737:chemistry / Q000235:genetics; D005340:Fibrinogen / Q000737:chemistry*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry; D010973:Platelet Adhesiveness; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D010455:Peptides; D011994:Recombinant Proteins; D014867:Water; D005340:Fibrinogen; D004549:Elastin