Kaihara S, Kim S S, Benvenuto M, Choi R, Kim B S, Mooney D, Tanaka K, Vacanti J P
Department of Surgery, Children's Hospital & Harvard Medical School, Boston, Massachusetts 02115, USA.
Transplantation. 1999 Jan 27;67(2):241-5. doi: 10.1097/00007890-199901270-00009.
Previous work from this laboratory has shown that isolated intestinal epithelial organoid units on porous biodegradable polymer scaffolds formed vascularized cysts lined by a neomucosa. The purpose of this study was to demonstrate anastomosis between tissue-engineered intestine and the native small bowel and to observe the effect of this anastomosis on cyst growth.
Intestinal epithelial organoid units from neonatal Lewis rats were seeded onto porous biodegradable polymer tubes made of polyglycolic acid, and they were implanted into the omentum of adult male Lewis rats. Three weeks after implantation, the unit-polymer constructs were anastomosed in a side-to-side fashion to the native jejunum in 20 rats (group 1). The other 18 rats were closed without anastomosis (group 2). All 38 tissue-engineered constructs were harvested 10 weeks after implantation. Four rats underwent upper gastrointestinal (GI) study before they were killed.
The rats in group 1 increased their body weights equal to those in group 2, and there was no statistically significant difference between the two groups. Upper GI examinations revealed no evidence of either bowel stenosis or obstruction at the anastomotic site. Grossly, the patency of the anastomosis was 90% and the lumen of the cyst was visualized by the upper GI study. At the second operation, there was no significant difference in the size of the cysts in either group: however, at the time the rats were killed, the length of the cysts in group 1 was significantly longer than that in group 2 (P<0.05 using Mann-Whitney U test). Histological examination showed that cysts after anastomosis were lined by a neomucosa in continuity to native small bowel across the anastomotic site and also demonstrated crypt-villus structures. Morphometric study demonstrated that cysts in group 1 had significantly greater villus number, height, and surface length than did those in group 2.
Anastomosis between tissue-engineered intestine and native small bowel resulted in no complications after the operation, kept a high patency rate, and maintained mucosal continuity between the tissue-engineered intestine and native small bowel. Furthermore, anastomosis had a positive effect on cyst size and development of the mucosa in the tissue-engineered intestine.
本实验室之前的研究表明，在多孔可生物降解聚合物支架上分离出的肠上皮类器官单元可形成由新黏膜衬里的血管化囊肿。本研究的目的是证明组织工程化小肠与天然小肠之间的吻合，并观察这种吻合对囊肿生长的影响。
将新生Lewis大鼠的肠上皮类器官单元接种到由聚乙醇酸制成的多孔可生物降解聚合物管上，并将其植入成年雄性Lewis大鼠的大网膜中。植入3周后，将20只大鼠（第1组）的单元 - 聚合物构建体以侧 - 侧方式与天然空肠进行吻合。另外18只大鼠不进行吻合直接缝合（第2组）。所有38个组织工程构建体在植入10周后收获。4只大鼠在处死前接受了上消化道（GI）检查。
第1组大鼠体重增加与第2组相当，两组之间无统计学显著差异。上消化道检查未发现吻合部位有肠狭窄或梗阻的迹象。大体观察，吻合的通畅率为90%，上消化道检查可看到囊肿腔。在第二次手术时，两组囊肿大小无显著差异；然而，在处死大鼠时，第1组囊肿的长度明显长于第2组（使用Mann - Whitney U检验，P<0.05）。组织学检查显示，吻合后的囊肿由新黏膜衬里，该新黏膜在吻合部位与天然小肠连续，并且还显示出隐窝 - 绒毛结构。形态计量学研究表明，第1组囊肿的绒毛数量、高度和表面积明显大于第2组。
组织工程化小肠与天然小肠之间的吻合术后未出现并发症，保持了较高的通畅率，并维持了组织工程化小肠与天然小肠之间的黏膜连续性。此外，吻合对组织工程化小肠中囊肿大小和黏膜发育有积极影响。
