Daniele B, D'Agostino L
Divisione di Oncologia Medica B, Facoltà di Medicina, Università Federico II, Napoli, Italy.
Ital J Gastroenterol. 1994 Dec;26(9):459-70.
The small intestinal epithelium is a continuously renewing cell system in which two main compartments can be defined: the crypt compartment and the villus compartment. The crypt compartment houses the proliferative cells (stem cells) that give birth to the four types of differentiated enterocytes (absorptive enterocytes, goblet cells, enteroendocrine cells, Paneth cells) that, with the exception of Paneth cells, populate the villus compartment. Enterocyte proliferation, differentiation and migration are regulated by a complex network of cell-cell and cell-matrix information, and modulated by growth factors, luminal factors and, possibly, hormones. The intimate mechanisms underlying the fascinating life of the enterocytes are the object of intensive investigation although insights have come from studies "in vitro" and in transgenic animals. The enormous proliferative potential makes the small bowel an extremely plastic organ, able to adapt to various injuries and adverse conditions and to completely recover even from extensive damage. Knowledge of the biologic mechanisms of adaptation has begun to affect therapeutic approaches to a number of intestinal diseases and the future will see a significant advancement in their management. More important, understanding the molecular mechanisms regulating the perfect equilibrium between proliferation and differentiation of the intestinal enterocytes will eventually help disclose the dark side of cancer.
小肠上皮是一个不断更新的细胞系统，其中可定义两个主要部分：隐窝部分和绒毛部分。隐窝部分容纳增殖细胞（干细胞），这些干细胞产生四种分化的肠上皮细胞（吸收性肠上皮细胞、杯状细胞、肠内分泌细胞、潘氏细胞），除潘氏细胞外，其余细胞分布于绒毛部分。肠上皮细胞的增殖、分化和迁移受细胞间和细胞与基质信息的复杂网络调控，并受生长因子、腔内因子以及可能的激素调节。尽管已经从“体外”研究和转基因动物研究中获得了一些见解，但肠上皮细胞迷人生命背后的具体机制仍是深入研究的对象。巨大的增殖潜力使小肠成为一个极具可塑性的器官，能够适应各种损伤和不利条件，甚至从广泛损伤中完全恢复。对适应生物学机制的了解已开始影响多种肠道疾病的治疗方法，未来其治疗管理将取得重大进展。更重要的是，了解调节肠道肠上皮细胞增殖与分化完美平衡的分子机制最终将有助于揭示癌症的阴暗面。
