Development of ureteral grafts by seeding adipose mesenchymal stem cells into a porcine ureteric scaffold

FRAUNHOFFER N; MEILERMAN A; LANGE F; DE LA ROSA L; GUERRIERI DIEGO; BARRIOS M; FERRARIS S; CHULUYAN EDUARDO

Halifax

Congreso; Joint Scientific Meeting of the Canadian Society of Transplantation and the Cell Transplant and Regenerative Medicine Society; 2017

CANADIAN SOCIETY OF TRANSPLANTATION SOCIÉTÉ CANADIENNE DE TRANSPLANTATION

Background: Ureteral injuries account for about 3% of urogenital traumas. Decellularized tissues have emerged as suitable alternative to ureteral repair but the currently available protocols have failed in functional host integration. The aim of this study was to develop a ureteral graft from porcine ureteric scaffold, seeded with adipose mesenchymal stem cells (aMSCs). Methods: 4 ureteral samples from healthy pigs were used. Tissues were decellularized using Triton X-100 1% and SDS 0.1% for 7 days under intraluminal continuous perfusion in a bioreactor designed by our group. Recellularization was performed with aMSCs extracted from sheep adipose tissue and seeded on the ureteric scaffold for 24 hours. Then, aMSCs were crosslinked to the scaffold with ethanol. Decellularization and structural integrity were characterized by histological analysis, β-actin western blot, residual DNA content and scanning electron microscopy (SEM). Extracellular matrix (EMC) proteins (collagen I and IV, laminin, fibronectin and elastin) and VEGF were studied by immunohistochemistry. Recellularization was evaluated by histological analysis. In addition, 41 growth factors were analyzed by protein array in the cellular and ECM fraction. Results: Decellularized ureteral grafts did not show cellular residues, significant DNA and β-actin levels. High structural integrity was observed by SEM. After cellularization with aMSC, the grafts analysis showed the presence of groups of aMSCs along the scaffold. Furthermore, 32 two growth factors were detected in the cellular fraction (> 50%), whereas matrix fraction was rich in bNGF, GCSF, TGF-β, VEGF and VEGF-D. Conclusions: These results indicate that the protocol used is successful to achieve a decellularized ureter with an intact native architecture. Furthermore, recellularization is possible with aMSCs, resulting in a graft with highly express growth factors levels. Therefore, our results suggest that porcine ureteral scaffold seeded with aMSCs may be a feasible tissue for ureteral repair.