title: Characterization of Endothelial Progenitor Cell Interactions with Human Tropoelastin.
abstract: The deployment of endovascular implants such as stents in the treatment of cardiovascular disease damages the vascular endothelium, increasing the risk of thrombosis and promoting neointimal hyperplasia. The rapid restoration of a functional endothelium is known to reduce these complications. Circulating endothelial progenitor cells (EPCs) are increasingly recognized as important contributors to device re-endothelialization. Extracellular matrix proteins prominent in the vessel wall may enhance EPC-directed re-endothelialization. We examined attachment, spreading and proliferation on recombinant human tropoelastin (rhTE) and investigated the mechanism and site of interaction. EPCs attached and spread on rhTE in a dose dependent manner, reaching a maximal level of 56±3% and 54±3%, respectively. EPC proliferation on rhTE was comparable to vitronectin, fibronectin and collagen. EDTA, but not heparan sulfate or lactose, reduced EPC attachment by 81±3%, while full attachment was recovered after add-back of manganese, inferring a classical integrin-mediated interaction. Integrin αVβ3 blocking antibodies decreased EPC adhesion and spreading on rhTE by 39±3% and 56±10% respectively, demonstrating a large contribution from this specific integrin. Attachment of EPCs on N-terminal rhTE constructs N25 and N18 accounted for most of this interaction, accompanied by comparable spreading. In contrast, attachment and spreading on N10 was negligible. αVβ3 blocking antibodies reduced EPC spreading on both N25 and N18 by 45±4% and 42±14%, respectively. In conclusion, rhTE supports EPC binding via an integrin mechanism involving αVβ3. N25 and N18, but not N10 constructs of rhTE contribute to EPC binding. The regulation of EPC activity by rhTE may have implications for modulation of the vascular biocompatibility of endovascular implants.
authors.affiliation: Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, 2050, Australia; The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Young
authors.initials: Y
authors.lastname: Yu
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia; School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Steven G
authors.initials: SG
authors.lastname: Wise
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Praveesuda L
authors.initials: PL
authors.lastname: Michael
authors.affiliation: School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Daniel V
authors.initials: DV
authors.lastname: Bax
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Gloria S C
authors.initials: GS
authors.lastname: Yuen
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia; School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Matti A
authors.initials: MA
authors.lastname: Hiob
authors.affiliation: School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Giselle C
authors.initials: GC
authors.lastname: Yeo
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Elysse C
authors.initials: EC
authors.lastname: Filipe
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Louise L
authors.initials: LL
authors.lastname: Dunn
authors.affiliation: Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, 2050, Australia; The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Kim H
authors.initials: KH
authors.lastname: Chan
authors.affiliation: The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Hamid
authors.initials: H
authors.lastname: Hajian
authors.affiliation: Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, 2050, Australia; The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: David S
authors.initials: DS
authors.lastname: Celermajer
authors.affiliation: School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia; Bosch Institute, University of Sydney, Sydney, NSW, 2006, Australia; Charles Perkins Centre, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Weiss
authors.affiliation: Department of Cardiology, Royal Prince Alfred Hospital, Sydney, NSW, 2050, Australia; The Heart Research Institute, Sydney, NSW, 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, 2006, Australia.
authors.forename: Martin K C
authors.initials: MK
authors.lastname: Ng
mesh_terms: D000328:Adult; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D066026:Endothelial Progenitor Cells / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008297:Male; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D015607:Stents; D054457:Tissue Scaffolds / Q000737:chemistry; D014333:Tropoelastin / Q000378:metabolism / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D011994:Recombinant Proteins; D014333:Tropoelastin