Miki H, Ando N, Ozawa S, Sato M, Hayashi K, Kitajima M
Department of Surgery, School of Medicine, Keio University, Tokyo, Japan.
ASAIO J. 1999 Sep-Oct;45(5):502-8. doi: 10.1097/00002480-199909000-00025.
We have been developing an artificial esophagus constructed of autologous esophageal component cells by cell culture. Because human esophageal epithelial cells are stratified in 20 layers, we attempted to construct an artificial esophageal epithelium 20 twenty layers thick. In in vitro experiments, we investigated how keratinocyte growth factor produced by fibroblasts accelerates the proliferation and differentiation of epithelial cells. Esophageal epithelial cells were cultured on collagen sheets in which dermal fibroblasts (0, 1, 4, 8 x 10(5) cells/ml of collagen) were embedded. In cultured epithelial cells on collagen gels without fibroblasts, 2.1 layer stratification was observed on the 21st day. With 1 x 10(5) fibroblasts/ml of collagen, 3.0 layer stratification was observed, 5.0 layers with 4 x 10(5) fibroblasts, and 18.1 layers with 8 x 10(5) fibroblasts. The degree of epithelial cell stratification was thus correlated with the number of embedded fibroblasts. Tubes constructed of a polyglycolic acid mesh frame, a collagen layer with esophageal fibroblasts, and an inner layer of esophageal epithelial cells were transplanted into muscle flaps of athymic rats. The luminal structures were observed to be patent without stenosis for 14 days. Histology of the epithelium revealed 20 layers of stratification. We thus succeeded in constructing epithelium similar to human esophageal epithelium. In the future we will attempt to use the tubular structures as a substitute for the esophagus after esophagectomy.
我们一直在通过细胞培养开发一种由自体食管组成细胞构建的人工食管。由于人类食管上皮细胞分层为20层，我们试图构建一层20层厚的人工食管上皮。在体外实验中，我们研究了成纤维细胞产生的角质形成细胞生长因子如何加速上皮细胞的增殖和分化。将食管上皮细胞培养在嵌入了真皮成纤维细胞（0、1、4、8×10⁵个细胞/毫升胶原蛋白）的胶原片上。在没有成纤维细胞的胶原凝胶上培养的上皮细胞中，在第21天观察到2.1层分层。每毫升胶原蛋白含有1×10⁵个成纤维细胞时，观察到3.0层分层，4×10⁵个成纤维细胞时为5.0层，8×10⁵个成纤维细胞时为18.1层。因此，上皮细胞分层程度与嵌入的成纤维细胞数量相关。由聚乙醇酸网框架、带有食管成纤维细胞的胶原层和食管上皮细胞内层构建的管子被移植到无胸腺大鼠的肌瓣中。观察到管腔结构在14天内通畅无狭窄。上皮组织学显示有20层分层。因此，我们成功构建了类似于人类食管上皮的上皮。未来我们将尝试将管状结构用作食管切除术后食管的替代品。
