RESUMO
PURPOSE: We studied the feasibility and results of a tissue-engineered ileal conduit using a poly (epsilon-caprolactone) (PCL) nano-sheet seeded with muscle-derived stem cells to replace a conventional ileal conduit in rats. MATERIALS AND METHODS: Muscle-derived stem cells were isolated from the gastrocnemius muscle of female Sprague-Dawley rats (200-250 g, n=6) by use of a preplate technique and were cultured on a PCL nano-sheet. The PCL nano-sheet was implanted into the omentum of rats and was then made into a conical shaped conduit. Rats were sacrificed 4 and 8 weeks after implantation, and morphologic changes were assessed by H&E and immunofluorescence staining, including DAPI staining and staining for myogenin and myosin heavy chain (MyHC). RESULTS: All rats survived until the end of the experiment. A minimal inflammatory reaction was observed around the PCL nano-sheet in the 4 week specimens but was found to be reduced in the 8 week specimen. Muscle bundles were identified at week 4 as well as week 8 after implantation on H&E staining. Around the PCL sheet, immunostaining for both myogenin and MyHC were positive, indicating skeletal muscle differentiation and ingrowth into the PCL sheet. CONCLUSIONS: A PCL nano-sheet seeded with muscle-derived stem cells showed successful skeletal muscle differentiation at 4 and 8 weeks after implantation. This preliminary result supports the feasibility of a tissue-engineered ileal conduit using a PCL nano-sheet (seeded with muscle-derived stem cells) in place of conventional ileal conduits.