Cholesterol-derivatized polyurethane: characterization and endothelial cell adhesion.
Endothelialization of synthetic surfaces has been challenging with limited success thus far. We investigated the hypothesis that covalent attachment of cholesterol to polyurethane via the urethane nitrogen groups would create a high-affinity surface for attachment and adhesion of endothelial cells. Cholesterol was covalently bound to the polyether polyurethane, Tecothane, by first derivatizing the polyurethane nitrogen groups with bromoalkyl side chains, followed by reacting mercapto-cholesterol to the bromoalkyl sites. Cholesterol-modified polyurethane demonstrated a qualitatively smoother surface per atomic force microscopy than nonmodified and increased surface energy (contact angle measurements) compared with unmodified polyurethane. Cell attachment assays showed a significantly greater number of attached bovine arterial endothelial cells (p = 0.0003) after 45 min of seeding on cholesterol-modified polyurethane versus unmodified polyurethane. Bovine arterial endothelial cells cultivated on cholesterol-modified Tecothane showed significantly greater levels of cell retention compared with unmodified Tecothane when exposed to arterial level shear stress for 2 h (25 dynes/cm2) with 90.0 +/- 6.23% cells remaining adherent compared with unmodified polyurethane, 41.4 +/- 11.7%, p = 0.0070. Furthermore, ovine endothelial precursors, obtained as blood outgrowth endothelial cells, were seeded on cholesterol-modified polyurethane and exposed to 25 dynes/cm2 shear conditions for 2 h, with the retention of 90.30 +/- 3.25% of seeded cells versus unmodified polyurethane, which retained only 4.56 +/- 0.85% (p < 0.001). It is concluded that covalently linking cholesterol to polyurethane results in improved material properties that permit increased endothelial cell retention compared with unmodified polyurethane.
Stachelek
Stanley J
SJ
Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104-4318, USA.
Alferiev
Ivan
I
Choi
Hoon
H
Kronsteiner
Allyson
A
Uttayarat
Pimporn
P
Gooch
Keith J
KJ
Composto
Russell J
RJ
Chen
I-Wei
IW
Hebbel
Robert P
RP
Levy
Robert J
RJ
D000818:Animals; D002417:Cattle; D002448:Cell Adhesion; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D002784:Cholesterol / Q000737:chemistry*; D042783:Endothelial Cells / Q000166:cytology*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D011140:Polyurethanes / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013314:Stress, Mechanical; D013696:Temperature
D011140:Polyurethanes; D002784:Cholesterol