Endothelium properties of a tissue-engineered blood vessel for small-diameter vascular reconstruction.
OBJECTIVE
A tissue-engineered blood vessel (TEBV) produced in vitro by the self-assembly method was developed in our laboratory for the replacement of small-diameter blood vessels. The interior of this vessel is covered by an endothelium. The aim of the present study was to evaluate whether the endothelial layer would make a favorable contribution at the time of implantation of the TEBV by investigating in vitro the hemocompatible properties of the endothelial cells covering its interior.


METHODS
The secretion of the von Willebrand factor (vWF) and expression of thrombomodulin by the endothelium were assessed, and the adhesive molecules E-selectin and intercellular adhesion molecule-1 (ICAM-1) were quantified as a function of maturation time. To evaluate the functional response of the endothelium on injury, the cellular response to physiological stimulatory factors (thrombin and lipopolysaccharide [LPS]) was analyzed.


RESULTS
The endothelial cells formed a confluent monolayer displaying favorable hemocompatible properties (78% +/- 10% of cells expressing thrombomodulin with only 12 +/- 3 mU/10(6) cells of vWF secreted over a 2-hour period), which acquired their full expression after a culture period of 4 days. Moreover, pro-adhesive properties toward inflammatory cells were not observed. The cells were also able to respond to physiological-stimulating agents (thrombin and LPS) and demonstrated a statistically significant overexpression of the corresponding molecules under the conditions tested.


CONCLUSIONS
These results indicate that the endothelium of the tissue-engineered blood vessel produced by the self-assembly approach displays advantageous qualities with regard to the vessel's future implantation as a small-diameter vascular prosthesis.
Laboratoire d'organogénèse expérimentale (LOEX), Saint Sacrement Hospital, Laval University, Quebec, Canada.
Murielle
M
Rémy-Zolghadri
Josée
J
Laganière
Jean-François
JF
Oligny
Lucie
L
Germain
François A
FA
Auger
D001808:Blood Vessels / Q000378:metabolism / Q000502:physiology; D002478:Cells, Cultured; D019040:E-Selectin / Q000096:biosynthesis*; D004730:Endothelium, Vascular / Q000378:metabolism / Q000502:physiology*; D005434:Flow Cytometry; D006487:Hemostasis / Q000502:physiology; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis*; D018180:Thrombomodulin / Q000096:biosynthesis*; D023822:Tissue Engineering / Q000379:methods*; D014471:Umbilical Veins / Q000166:cytology / Q000502:physiology; D014841:von Willebrand Factor / Q000096:biosynthesis*
D019040:E-Selectin; D018180:Thrombomodulin; D014841:von Willebrand Factor; D018799:Intercellular Adhesion Molecule-1