A surface-modified biodegradable urethral scaffold seeded with urethral epithelial cells

Background Efficient cell adhesion and proliferation is a central issue in cell-based tissue engineering, which offers great promise for repair of urethral defects or strictures. This study evaluated the adhesion and growth of rabbit uroepithelium on a surface-modified three-dimensional poly-L-lactic acid （PLLA） scaffold.Methods Urethral mucosa were harvested from male New Zealand rabbits and the urothelium were dissociated and then cultured. Immunocytochemistry on cultured uroepithelium for pancytokeratin and uroplakin Ⅱ and TE-7 confirmed pure populations. After in vitro proliferation, cells were seeded onto a surface-modified urethral scaffold with non-knitted filaments. The morphology and viability of the cells were examined by immunohistochemical and fluorescence staining.Inverted and scanning microscopes were used to document cell growth and adhesion.Results Three to five days after primary culture, the uroepithelial cells gradually became confluent, assuming a cobblestone pattern. The filaments of the urethral scaffold had excellent biocompatibility and allowed growth of the uroepithelium, without affecting viability. The uroepithelial cells adhered to and grew well on the scaffold. After 3-7 days,the cells grew vigorously and meshes of the scaffold were full of uroepitheliums.Conclusions The surface-modified urethral scaffold with non-knitted filaments allows the growth of uroepithelium and can serve as a carrier for the tissue engineering of urethra.