title: Effect of immobilized collagen type IV on biological properties of endothelial cells for the enhanced endothelialization of synthetic vascular graft materials.
abstract: Regeneration of healthy endothelium onto vascular graft materials is imperative for prevention of intimal hyperplasia and thrombogenesis. In this study, we investigated the effect of collagen type IV (COL-IV) immobilized onto electrospun nanofibers on modulation of endothelial cell (EC) function, as a potential signal to rapid endothelialization of vascular grafts. COL-IV is assembled in basement membrane underneath intimal layer and regulates morphogenesis of blood vessels. For immobilization of COL-IV, poly(l-lactic acid) (PLLA) nanofibers (PL) were prepared as a model vascular graft substrate, onto which acrylic acid (AAc) was then grafted by using gamma-ray irradiation. AAc graft was dependent on irradiation doses and AAc concentrations, which allowed us to select the condition of 5% (v/v) AAc and 10 kGy for further conjugation of COL-IV. COL-IV immobilization was proportionally controlled as a function of its concentration. Atomic force microscope (AFM) analysis qualitatively supported immobilization of COL-IV, demonstrating increase in root mean square roughness of the PL from 665.37 ± 13.20 nm to 1440.74 ± 33.24. However, the Young's modulus of nanofibers was retained as approximately 1 MPa, regardless of surface modification. The number of ECs attached on the nanofibers with immobilized COL-IV was significantly increased by 5 times (1052 ± 138 cells/mm(2)) from pristine PL (234 ± 41 cells/mm(2)). In addition, the effect of immobilized COL-IV was profound for enhancing proliferation and up-regulation of markers implicated in rapid endothelialization. Collectively, our results suggest that COL-IV immobilized onto electrospun PLLA nanofibers may serve as a promising instructive cue used in vascular graft materials.
authors.affiliation: Department of Bioengineering, Institute for Bioengineering and Biopharmaceutical Research, Hanyang University, Seoul 133-791, Republic of Korea; BK21 Plus Future Biopharmaceutical Human Resources Training and Research Team, Republic of Korea.
authors.forename: Yunhoe
authors.initials: Y
authors.lastname: Heo
authors.affiliation: Research Division for Industry and Environment, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Gumgugil, Jeongeup, Jeollabuk-do 580-185, Republic of Korea.
authors.forename: Young Min
authors.initials: YM
authors.lastname: Shin
authors.affiliation: Department of Bioengineering, Institute for Bioengineering and Biopharmaceutical Research, Hanyang University, Seoul 133-791, Republic of Korea; BK21 Plus Future Biopharmaceutical Human Resources Training and Research Team, Republic of Korea.
authors.forename: Yu Bin
authors.initials: YB
authors.lastname: Lee
authors.affiliation: Research Division for Industry and Environment, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Gumgugil, Jeongeup, Jeollabuk-do 580-185, Republic of Korea. Electronic address: ymlim71@kaeri.re.kr.
authors.forename: Youn Mook
authors.initials: YM
authors.lastname: Lim
authors.affiliation: Department of Bioengineering, Institute for Bioengineering and Biopharmaceutical Research, Hanyang University, Seoul 133-791, Republic of Korea; BK21 Plus Future Biopharmaceutical Human Resources Training and Research Team, Republic of Korea. Electronic address: hshin@hanyang.ac.kr.
authors.forename: Heungsoo
authors.initials: H
authors.lastname: Shin
mesh_terms: D001807:Blood Vessel Prosthesis; D049109:Cell Proliferation; D024141:Collagen Type IV / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D018625:Microscopy, Atomic Force; D057139:Nanofibers; D013499:Surface Properties
chemical_list: D024141:Collagen Type IV
keywords: Collagen type IV; Electrospinning; Endothelialization; Surface modification; Vascular graft