Evolution of mesenchymal cells in fetal rat lung
Abstract
The evolution of connective tissue cells in the developing fetal rat lung is studied under the electron microscope from the 15th until the 21st day of gestation and is compared to the evolution of epithelial cells. Three successive types of stem cells ("mesocytoblasts") are present during the first stages of lung development studied (15 to 18 days of gestation). These stem cells appear to be able to differentiate into fibroblasts or into smooth muscle cells, according to their localization along the broncho-alveolar tubule. Myoblasts are situated near the bronchial epithelium, whereas fibroblasts occur under the alveolar epithelium. Epithelo-mesenchymal interactions are assumed to play a role in this differentiation process. Synthesis of both, collagen and elastic fibers and of cytoplasmic filaments by fibroblasts as well as by myoblasts reveal the multiple potentialities of the mesenchymal stem cell and suggest a common origin. The early fibroblast in characterized by long cytoplasmic processes which contain numerous cytofilaments, and by the presence of collagen fibers in the vicinity of the cell. Later on, (20 days of gestation) the mature fibroblast of the lung mesenchyme shows areas of RER, glycogen and lipidic vacuoles in...Continue Reading
References
Structural features of the epithelio-mesenchymal interface of rat duodenal mucosa during development
Citations
Related Concepts
Related Feeds
Adult Stem Cells
Adult stem cells reside in unique niches that provide vital cues for their survival, self-renewal, and differentiation. They hold great promise for use in tissue repair and regeneration as a novel therapeutic strategies. Here is the latest research.