PLACEMENT OF ENDOTHELIAL-CELLS ON THE LUMINAL SURFACE OF DENUDED ARTERIES IN-VITRO AND IN-VIVO

PURPOSE: Experiments were performed to determine if the percutaneous p lacement of endothelial cells on denuded arterial surfaces is feasible . MATERIALS AND METHODS: For in vitro adhesion assays, rabbit microvas cular endothelial cells were stained with a fluorescent marker and pla ced on the luminal surface of disks of denuded rabbit aorta. At varyin g times thereafter, the nonadherent cells were removed, and the adhere nt cells were quantitated with use of fluorescence microscopy, For in vivo studies, angioplasty was performed on external iliac arteries in five rabbits, and a double-balloon catheter, positioned at the dilatat ion site, was used to deliver fluorescent rabbit microvascular endothe lial cells. Ten minutes (n = 2), 1 hour (n = 2), 1 day (n = 1), or 3 d ays (n = 1) after cell placement, the number of fluorescent cells rema ining on each artery was determined. RESULTS: In vitro rabbit microvas cular endothelial cell attachment was (a) serum-dependent, peaking wit h media containing 25% autologous serum; (b) time-dependent, peaking a t 30 minutes; and (c) cell density-dependent. In vivo rabbit microvasc ular endothelial cell attachment was (a) noncircumferential, (b) appea red to be gravity-dependent, and (c) appeared unchanged over 3 days wi th respect to number of cells per cross-section and length of artery h aving endothelium. CONCLUSIONS: Percutaneous delivery of endothelial c ells onto denuded arterial surfaces with use of optimal conditions is feasible and these cells remain adherent for at least 3 days.