Tissue engineering in urinary bladder: Morphological and functional characterization

Introduction: In the last years, tissue engineering has attracted lots of researchers, in urology too. This is due to the possibility to use this technique in several pathologies' therapies, which generally require reconstructive surgical solutions. Our work's aim is to evaluate morphological and functional aspects of cultivated urothelial and detrusorial tissues', both in "monolayer growth" and on scaffolds, in order to understand the chance of using them in reconstructive surgery. Materials and methods: tissue cultures of detrusorial and urothelial cells have been obtained from animals (pigs, rabbits) and men. The urothelial nature of obtained cells has been demonstrated by traditional histological observation (Hematoxylin - Eosin), by immuno-fluorescence assay (specific for cyto-keratins antibodies), by immuno-histo-chemistry techniques (using specific cyto-keratins 7, 17, and 20 antibodies). Detrusorial tissue has been studied by using antibodies specific for alpha-actin. Results: urothelial and smooth muscle cells, when isolated and expanded in vitro, keep the typical characteristics of original tissue, as showed by classical histological observation (H-E), immuno-histo-chemistry and immuno-fluorence assays. These results were positive both in monolayer colonies and on scaffolds. In vitro results are encouraging and they demonstrate that it is possible to obtain in vitro vesical tissue that could have analogous characteristics to the original organ; even though clinical utilisation of this technique must be more investigated, both in vitro and in vivo.