1 Adult Stem Cell Research Group, BioMediTech, Faculty of Medicine and Life Sciences, University of Tampere , Tampere, Finland .
2 Science Centre, Tampere University Hospital , Tampere, Finland .
Tissue Eng Part A. 2018 Jan;24(1-2):117-127. doi: 10.1089/ten.TEA.2016.0245. Epub 2017 Jul 21.
Urethral defects are normally reconstructed using a patient's own genital tissue; however, in severe cases, additional grafts are needed. We studied the suitability of poly(l-lactide-co-ɛ-caprolactone) (PLCL) and poly(trimethylene carbonate) (PTMC) membranes for urethral reconstruction in vivo. Further, the compatibility of the materials was evaluated in vitro with human urothelial cells (hUCs). The attachment and viability of hUCs and the expression of different urothelial cell markers (cytokeratin 7, 8, 19, and uroplakin Ia, Ib, and III) were studied after in vitro cell culture on PLCL and PTMC. For the in vivo study, 32 rabbits were divided into the PLCL (n = 15), PTMC (n = 15), and control or sham surgery (n = 2) groups. An oval urethral defect 1 × 2 cm in size was surgically excised and replaced with a PLCL or a PTMC membrane or urethral mucosa in sham surgery group. The rabbits were followed for 2, 4, and 16 weeks. After the follow-up, urethrography was performed to check the patency of the urethra. The defect area was excised for histological examination, where the epithelial integrity and structure, inflammation, and fibrosis were observed. There was no notable difference on hUCs attachment on PLCL and PTMC membranes after 1 day of cell seeding, further, the majority of hUCs were viable and maintained their urothelial phenotype on both biomaterials. Postoperatively, animals recovered well, and no severe strictures were discovered by urethrography. In histological examination, the urothelial integrity and structure developed toward a normal urothelium with only mild signs of fibrosis or inflammation. According to these results, PLCL and PTMC are both suitable for reconstructing urethral defects. There were no explicit differences between the PLCL and PTMC membranes. However, PTMC membranes were more flexible, easier to suture and shape, and developed significant epithelial integrity.
尿道缺陷通常使用患者自身的生殖器组织进行重建；然而，在严重的情况下，需要额外的移植物。我们研究了聚（L-丙交酯-co-ε-己内酯）（PLCL）和聚（三亚甲基碳酸酯）（PTMC）膜在体内用于尿道重建的适用性。此外，还在体外用人尿路上皮细胞（hUCs）评估了材料的相容性。研究了 hUCs 在 PLCL 和 PTMC 上体外细胞培养后的附着和活力，以及不同尿路上皮细胞标志物（细胞角蛋白 7、8、19 和尿路上皮蛋白 Ia、Ib 和 III）的表达。在体内研究中，将 32 只兔子分为 PLCL（n=15）、PTMC（n=15）和对照组或假手术组（n=2）。通过手术切除 1×2cm 的椭圆形尿道缺损，并用 PLCL 或 PTMC 膜或假手术组的尿道黏膜替换。兔子被随访 2、4 和 16 周。随访后，进行尿道造影以检查尿道通畅性。切除缺损区域进行组织学检查，观察上皮完整性和结构、炎症和纤维化。细胞接种后 1 天，hUCs 在 PLCL 和 PTMC 膜上的附着没有明显差异，此外，大多数 hUCs 存活并在两种生物材料上保持其尿路上皮表型。手术后，动物恢复良好，尿道造影未发现严重狭窄。组织学检查显示，尿路上皮完整性和结构向正常尿路上皮发展，只有轻度纤维化或炎症迹象。根据这些结果，PLCL 和 PTMC 均适合重建尿道缺损。PLCL 和 PTMC 膜之间没有明显差异。然而，PTMC 膜更具弹性，更容易缝合和塑形，并且具有显著的上皮完整性。
