| Short bowel syndrome (SBS) is the malabsorptive state that occurs after a massive loss of the small intestine. Intestinal tissue engineering is a promising therapy that may provide an ultimate solution for SBS. Architectural design of a scaffold that ensures adequate nutrient transport and vascularization in 3D constructs is crucial for the successful regeneration of small intestine. Moreover, tissue engineering scaffold should provide the appropriate growth factors with spatial and temporal control to simultaneously trigger the cell proliferation, differentiation, and intestinal tissue development. The objective in this dissertation is to develop the scaffold that mimics the intestinal microenvironments and evaluate its biological activity to regenerate functional intestinal tissue.;3D porous scaffolds containing fine villi architecture were constructed by a novel indirect 3D printing technique. In vitro, Intestinal epithelial cells (IEC6) or smooth muscle cells (SMC) attached to the scaffolds uniformly and grew preferentially in the villi region indicating that architectural design with higher surface area can improve mass transport and cell growth within 3D constructs. 3D scaffolds with intestinal microvasculature that can guide vessel ingrowth were also developed by vascular corrosion casting (VCC) technique with a new digesting protocol.;A release study demonstrated that growth factor release is highly influenced by scaffold surface, and the presence of ions, proteins, and cells in the media. The sustained release in this complex environment was demonstrated by encapsulating proteins into microspheres and their release was further controlled by changing the composition of microspheres. Furthermore, the material processing steps did not reduce the biologic activity of the released growth factors.;In vivo evaluation of SIS and PCL suggested that the previously reported intestinal tissue formation may have resulted from the contraction of the defect covered by SIS rather than true tissue regeneration. In vivo, bFGF releasing scaffold seeded with smooth muscle cells demonstrated a potential for the regeneration of the small intestinal muscle layer. Local delivery of bFGF induced significant blood vessel formation in the scaffold and enhanced engraftment of intestinal smooth muscle cell.;Collectively, our research findings provide an initial basis for optimizing the design rule of scaffolds for intestinal tissue engineering. |
