Flow Cytometric Analysis of Endothelial Cell Viability in Arterial Allograft / 대한흉부외과학회지

ABSTRACT

Arterial allografts have known advantages over prosthetic vascular conduit for treatment of heart valvular disease, congenital heart disease and aortic disease. Cell viability may play a role in determining the longterm outcome of allografts. Endothelial cell is one important part in determining the allograft viability. To evaluate the viability of endothelial cells using current allograft preservation technique, porcine heart valve leaflets and arterial wall were subjected to collagenase digestion. Single endothelial cell suspension was labeled with GSA-FITC(Griffonia simplicifolia agglutinin- fluorescein isothiocyanate), a vascular endothelial cell specific marker. The cell suspension was washed and incubated with PI(Propidium Iodide), which does not bind with viable cells. Endothelial cell viability was evaluated by calculating the percentage of GSA-FITC(+) and PI(-) group using flowcytometric analysis. Allografts were treated with 4degrees C antibiotic solution for 24 hours for sterilization. After this, half of allografts were stored in 4degrees C RPMI 1640 with HEPES buffer culture medium with 10% fetal bovine serum for 1 to 14 days(Group I). Another half of allografts were cryopreserved with a currently used technique (Group II). During the procurement and sterilization of arterial allografts, 22.8% and 24.4% of endothelial cell viability declined, respectively. In Group I, 11.9% of endothelial cell viability declined further steadily during 14 days of storage. In Group II, 13.7% of endothelial cell viability declined. These results show that largest loss of endothelial cell viability occurs during the initial process. After 14 days of arterial allograft storage under 4degrees C nutrient medium or cryopreservation, about 40% of endothelial cell viability is maintained. There were no differences between the endothelial cell viability from aortic valve leaflet, pulmonic valve leaflets, aortic wall and pulmonic wall.