Seeding mesenchymal stem cells onto PLGA/collagen compound scaffold for bladder reconstruction in a rabbit model

Urinary bladder loss is one of the major problems due to congenital, trauma or malignancies. The traditional bladder reconstructive surgery with gastrointestinal segments has various complications. Therefore, we evaluated the alternative artificial bladder reconstructive surgery with seeding mesenchymal stem cells induced by Platelet-Derived growth factor-BB into PLGA/collagen compound scaffold in rabbit model. Total 21 male rabbits were randomly grouped: Group A (n=9), Group B (n=9), and Group C (n=3, control) with mesenchymal stem cells seeded into PLGA/collagen compound scaffold, small intestinal submucosa, and none, respectively. Bladder volume was tested preoperatively and at 4, 8, and 12 weeks postoperatively along with cystography at the same time. Additionally, H&E staining and immunohistochemistry with CD31 and smooth muscle-actin (alpha-SMA) monoclonal antibody were performed to observe regeneration of urothelium and smooth muscle cells. Our results exhibited a good bio-compatibility with PLGA/collagen compound scaffold. The thickness of the grated segment were similar in Group A and B, close to native bladder tissue (Group C) at 12 weeks postoperatively. The bladder capacities in Group A were significantly better than that of the Group B (46.17 +/- 1.62 ml vs. 40.52 +/- 1.26 ml, P<0.05). Moreover, cystography revealed a better shape of reconstructed bladders in Group A. The histology and immunohistochemistry results of Group A demonstrated better well-regeneration of urothelium and smooth muscle cells, sustained positively for CD31 and alpha-SMA than that of Group B. In summary our study results suggested that seeding MSCs into PLGA/collagen compound scaffold promotes regeneration of the urothelium and smooth muscle cells in a rabbit model. Therefore, PLGA/collagen compound scaffold could be more suitable for bladder regeneration than SIS.