Interaction of epithelium with mesenchyme affects global features of lung

of epithelium with mesenchyme affects global features of lung architecture: a computer model of development. J Appl Physiol 102: 294 –305, 2007. First published September 14, 2006; doi:10.1152/japplphysiol.00665.2006. — Lung airway morphogen-esis is simulated in a simplified diffusing environment that simu-lates the mesenchyme to explore the role of morphogens in airway architecture development. Simple rules govern local branching morphogenesis. Morphogen gradients are modeled by four pairs of sources and their diffusion through the mesenchyme. Sensitivity to lobar architecture and mesenchymal morphogen are explored. Even if the model accurately represents observed patterns of local development, it could not produce realistic global patterns of lung architecture if interaction with its environment was not taken into account, implying that reciprocal interaction between airway growth and morphogens in the mesenchyme plays a critical role i