Tubularized Urethral Replacement Using Tissue-Engineered Peritoneum-Like Tissue in a Rabbit Model

Abstract

Introduction: This study aims to investigate whether mesothelial cells could function as seed cells to construct tissue-engineered peritoneum-like tissue for urethral reconstruction in a rabbit model. Materials and Methods: Bladder acellular matrices were prepared and trimmed to 1.5 × 1 cm. Nine male rabbits underwent omentum biopsy and autologous mesothelial cells were isolated. After in vitro expansion, the cells were seeded onto the matrices and incubated for 7 days. In 18 rabbits, a pendulous urethral segment 1.5 cm long was totally excised and urethroplasty was performed with tubularized matrices seeded with cells in 9 animals and without cells in 9 as controls. Urethrography was performed at 1, 2 and 6 months postoperatively. Meanwhile, the neourethras were harvested and analyzed grossly and histologically. Results: Histological analysis of the cell-seeded grafts revealed a loose collagen matrix covered with a single layer of mesothelim. Serial urethrography indicated a wide urethral caliber without stricture formation in animals implanted with cell-seeded matrices, while all animals of the control group developed stricture. Histological analysis of the implanted cell-seeded matrices demonstrated a normal urethral architecture by 1 month, composed of multilayers of urothelium surrounded by smooth muscle bundles, which became increasingly organized with time. By 6 months, the neourethra could be hardly distinguished from native urethra both grossly and histologically. Conclusions: Autologous mesothelial cells could be successfully used as seed cells for tubularized urethral reconstruction in male rabbits.

Urethral reconstruction with autologous urine-derived stem cells seeded in three-dimensional porous small intestinal submucosa in a rabbit model

“…Two types of cells have been introduced for urethral reconstruction. First, adult cells, such as UCs [5, 34, 35], epidermal cells [36], SMCs [37], lingual keratinocytes [37, 38], mesothelial cells [39], and fibroblasts [38], have often been used. However, culturing of these cells has a low success rate, and they also have a limited expansion capability in culture.…”

Urethral tissue regeneration using collagen scaffold modified with collagen binding VEGF in a beagle model

“…To date, many attempts have been made to determine appropriate substitutes for urethral reconstruction, and in general, it is believed that seeding cells is necessary for constructing an artificial biomaterial scaffold that is suitable for reconstruction of extensive urethral defects. Various types of cells have been adopted in animal and clinical experiments, such as bone marrow mesenchymal stem cells [19][20][21], urethral epithelial cells [22] and smooth muscle cells [6,7,[23][24][25], urine-derived stem cells [26], mesothelial cells [27], adipose-derived stem Cells [28,29], and oral keratinocytes [30], and other cell types.…”

Development of a Bioreactor to Culture Tissue Engineered Ureters Based on the Application of Tubular OPTIMAIX 3D Scaffolds

“…This construct is then cultivated and functionalized in-vitro before it is used to replace damaged organs [12]. The importance of cells within a biomaterial was already shown in previous studies [12,13]. It was demonstrated that a seeding prior to the implantation could for example counteract a shrinkage and stricture formation.…”