Co-culture of smooth muscle cells and endothelial cells on three-dimensional bioprinted polycaprolactone scaffolds for cavernosal tissue engineering

Purpose: In vitro evaluation of polycaprolactone (PCL) scaffolds fabricated by a three-dimensional (3D) printing technique for tissue engineering applications in the corpus cavernosum. Materials and methods: PCL scaffolds were fabricated by use of a 3 D bioprinting system. The 3D-printed scaffolds had interconnected structures for cell ingrowth. Human aortic smooth muscle cells (haSMCs) were seeded on the scaffold and cultured for 5 days, and then human umbilical vein endothelial cells (HUVECs) were also added on the scaffolds and co-cultured with haSMCs for up to 7 days. The ability of these scaffolds to support the growth of HUVECs and haSMCs was investigated in vitro. 3 D strand-deposited scaffolds were characterized by scanning electron microscopy (SEM) images and porosity measurement. Results: SEM images showed the surface of the PCL scaffolds to be well covered by HUVECs and haSMCs. Immunofluorescent staining of alpha-flk1 and alpha-smooth muscle actin on the HUVECs and haSMCs seeded scaffolds confirmed that the cells remained viable and proliferated throughout the time course of the culture. Conclusion: 3 D bioprinting of a PCL scaffold is feasible for co-culturing of HUVECs and haSMCs. This was a preliminary study to investigate the possibility of fabrication of tissue-engineered corpus cavernosum.