[Experimental study about viability of autologous free graft in vitro cultivated urinary epithelium].
OBJECTIVE
The purpose of this study is to apply the in vitro keratinocyte culture techniques and the tissue engineering principles to urothelium, to obtain a three-dimensional autologous tissue suitable for grafting. We also showed the viability of free graft cultured urothelium in an experimental model.


METHODS
An animal experimental model was designed to apply the techniques of cellular culture and tissue engineering. Biopsy specimens of bladder mucosa were obtained, in vitro cultured and posteriorly implanted in each animal. We established three groups based on different follow-up periods (7, 14 and 30 days), and made a final histomorphological study to demonstrate the viability of the graft at the end of its respective follow-up period.


RESULTS
A three-dimensional in vitro tissue was obtained, composed of a bio-artificial submucosa (fibrin gel and fibroblast) where the uroepithelial cells were seeding; a biodegradable polyglycolic acid mesh was used to facilitate the tissue manipulation and implantation. In the morphological study all the implants appeared viable, but the grafts with longer implantations periods were better conformed, showing a tisular structure with multiple cellular layers.


CONCLUSIONS
In vitro keratinocyte culture techniques could be applied to other epithelial tissues as the urothelium. We obtained a three-dimensional in vitro tissue suitable for grafting in a relatively short time. The histological study demonstrated that free autologous urothelial graft is totally viable, opening future clinics applications.
de Diego Rodríguez
E
E
Servicio de Urología, Hospital Comarcal de Laredo, Cantabria.
Villanueva Peña
A
A
Roca Edreira
A
A
Martín García
B
B
Meana Infiesta
A
A
Gómez Llames
Sara
S
Gómez Román
J
J
D000818:Animals; D002452:Cell Count; D018929:Cell Culture Techniques / Q000379:methods; D004847:Epithelial Cells; D005260:Female; D008297:Male; D011817:Rabbits; D013997:Time Factors; D019459:Urothelium / Q000166:cytology / Q000637:transplantation*