|Budget Amount *help
¥14,900,000 (Direct Cost : ¥14,900,000)
Fiscal Year 2004 : ¥3,600,000 (Direct Cost : ¥3,600,000)
Fiscal Year 2003 : ¥3,600,000 (Direct Cost : ¥3,600,000)
Fiscal Year 2002 : ¥7,700,000 (Direct Cost : ¥7,700,000)
Research for the regeneration of the gastro-intestinal tract with in situ Tissue Engineering.
In this research program, we tried to regenerate the whole layers of digestive system using in situ Tissue Engineering technique. Targeted gastro-intestinal tract is composed of four layers ; the mucous epithelium, the sub-mucosal connective tissue, the muscle, and the serosa. The glands which produce digestive juice and the autosomal nerves are situated in these four layers. As a scaffold, collagen sponge and the PGA unwoven fabric were applied to the site of the regeneration. We tried repair of the defect of the stomach, the small intestine, the colon, the common bile duct of canine experimental model. We have already observed the early regeneration of the defective mucous epithelium, the connective tissue, and the glands in this system. However, the muscle layers (mainly the smooth muscle) failed to be regenerated. To solve this problem, we had added the growth factors (FGE,TGF β) but the effect was not obvious.
This may because of absence of the stem cell as well as poor blood supply. Therefore, in the last year of this project, the progenitor cells were isolated from the host muscle tissue and consequently proliferated in vitro. Then, we tried to apply these proliferated cells with vascular inductive growth factor such as VEGF to promote the regeneration of muscle tissue. Using this technique we confirmed that the muscle-like tissue could be produced in the lower extremities of rabbits.
We bridged the nerve defect of the intraabdominal autosomal nerve with artificial biodegradable nerve guide tube, in which the feasibility of the PGA-collagen tube as a nerve guide were strongly indicated. Thus, apparently, even in large mammalians such as beagle dog, it seems highly promizing to make a digestive tissue with a technique of in situ Tissue Engineering.