Jetten A M
Cell Biology Section, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709.
Am J Physiol. 1991 Jun;260(6 Pt 1):L361-73. doi: 10.1152/ajplung.1991.260.6.L361.
The normal tracheobronchial epithelium is continuously renewing itself: cells are lost and replaced by the proliferation and differentiation of stem cells. The proliferation and differentiation of these cells have to be tightly controlled in order to maintain the normal structure of the epithelium. A variety of biological and biochemical processes are involved in controlling the proliferation and differentiation of the tracheobronchial epithelium. Since the trachea and bronchus are comprised of a heterogeneous cell population, interactions between the different cell types are of crucial importance not only in controlling the normal maintenance of this tissue but also in the regulation of repair processes following injury and morphogenesis during lung development. A variety of factors, including several polypeptide growth factors and cytokines, have been identified that regulate positively or negatively the growth and differentiation of tracheobronchial epithelial cells by autocrine or paracrine mechanisms. Retinoids are another group of regulatory factors that appear to play a crucial role in controlling cell proliferation and differentiation in the tracheobronchial epithelium. Recently, many advances have been made in understanding the action of these agents in these cells. Alterations in the balance between growth and differentiation regulatory factors appear to play an important role in several pathophysiological changes such as hyperplasia, fibrosis, and neoplasia.
细胞会丢失，并通过干细胞的增殖和分化来替代。这些细胞的增殖和分化必须受到严格控制，以维持上皮的正常结构。多种生物学和生化过程参与控制气管支气管上皮的增殖和分化。由于气管和支气管由异质性细胞群体组成，不同细胞类型之间的相互作用不仅对于控制该组织的正常维持至关重要，而且对于肺发育过程中损伤后的修复过程和形态发生的调节也至关重要。已鉴定出多种因子，包括几种多肽生长因子和细胞因子，它们通过自分泌或旁分泌机制正向或负向调节气管支气管上皮细胞的生长和分化。类视黄醇是另一组调节因子，似乎在控制气管支气管上皮细胞的增殖和分化中起关键作用。最近，在理解这些因子在这些细胞中的作用方面取得了许多进展。生长和分化调节因子之间平衡的改变似乎在增生、纤维化和肿瘤形成等几种病理生理变化中起重要作用。
