Lung organogenesis is a developmental process that starts in human 4-5 weeks after conception and continues during the first years of life. It can be subdivided in six different stages: embryonic, pseudoglandular, canalicular, saccular and alveolar stage and stage of vascular maturation. In each of these periods, multiple molecules like transcription factors, growth factors and other signaling molecules and their respective receptors control and coordinate the course of events by a distinct expression and activity over space and time. Epithelial-mesenchymal interactions, physiological mechanical forces as well as humoral factors modulate some of these expression patterns. Although numerous key players and their mode of action have been discovered, many wait to be unveiled. Herein, we will summarize the current concepts of lung development with special consideration of the genetic control of lung genesis, growth and maturation.
Copyright 2003 S. Karger AG, Basel