Human Cardiac Valve Interstitial Cells in Collagen Sponge: A Biological Three-Dimensional Matrix for Tissue Engineering
Patricia M. Taylor PhD, Sean P. Allen PhD, Sally A. Dreger BSc, Magdi H. Yacoub FRS

The use of a biological, biodegradable scaffold remodeled by cells to resemble a valve leaflet is an attractive approach to tissue engineering. The study aim was to evaluate the suitability of a three-dimensional collagen sponge for maintenance of cell viability, proliferation and phenotype of cultured human cardiac valve interstitial cells (ICs). A panel of antibodies was used to determine expression of phenotypic markers in the native valve leaflet, as well as ICs cultured from valve leaflets plated on glass coverslips or seeded in collagen sponge. Results showed that the sponge enhanced the capacity of cells to express their original phenotype. Confocal microscopy of ICs within the sponge revealed the presence of cells with long interconnecting extensions. Cell proliferation and cell death assays established that cells were not only viable after four weeks in the sponge, but also were proliferating. This study demonstrated that collagen sponge is a suitable biodegradable scaffold for tissue engineering.