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Updated: Jun 28, 2026
09:58
A Method for Labeling Vasculature in Embryonic Mice
Published on: October 7, 2011
Emerging pulmonary vasculature lacks fate specification
Margaret A Schwarz1, Lauren Caldwell, Danielle Cafasso
1UT Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, TX 75390-9063, USA. margaret.schwarz@utsouthwestern.edu
Summary
Early lung development shows functional blood vessels forming in the mesenchyme, not the epithelium. Vascular endothelial growth factor (VEGF) signals guide these vessels, and arterial-venous identity is absent in the nascent pulmonary vasculature.
Area of Science:
- Developmental biology
- Vascular biology
- Respiratory system development
Background:
- Lung morphogenesis requires coordinated branching and vascularization.
- The origin and type of early lung blood vessels are not well understood.
Purpose of the Study:
- To investigate the origin and characteristics of nascent pulmonary vasculature.
- To elucidate the role of epithelial-derived signals in lung vascularization.
Main Methods:
- Immunostaining for EphrinB2 and EphB4.
- Observation of functional blood flow in developing lungs at embryonic days (E) 11.5 and E14.5.
- Analysis of endothelial cell behavior in response to vascular endothelial growth factor (VEGF) signals.
Main Results:
- Functional blood vessels are initially confined to the lung mesenchyme, distal to the epithelium.
- By E14.5, vessels extend towards the epithelium, guided by epithelial VEGF signals.
- Emergent pulmonary vasculature lacks distinguishable arterial and venous identity.
- Multipotent mesenchymal stromal cells are found adjacent to developing vessels.
Conclusions:
- Lung vascularization originates in the mesenchyme, distal to the epithelium.
- Arterial-venous specification is absent in the early lung vasculature.
- Epithelial VEGF signaling drives endothelial cell migration and morphogenesis during lung development.
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