Figure 2. Comparison of lungs in child with pulmonary lymphangiectasia and in neonatal CCSP-VEGF-C mice.

A-B, Widely dilated lymphatics (asterisks) in lung from a 1-month-old girl with pulmonary vein stenosis accompanied by lymphangiectasia (Case A). Sections from autopsy specimen stained by H&E (A) or D2-40/podoplanin (B, brown). C, Enlarged lymphatics in A and B are marked by dashed red lines. Other landmarks are shown by solid blue lines. Br, bronchiole; PA, pulmonary artery; and PV, pulmonary vein. D-E, Lung sections stained by H&E from neonatal CCSP-VEGF-C mice on water (D) or doxycycline (E) from P0 to P14. F, Regions of lymphangiectasia in E (asterisks) around bronchi and pulmonary vessels are outlined by dashed red lines. G-H, Sparse lymphatics around major bronchus and pulmonary vessels (arrows) in lung of control mouse on water (G) compared to widespread lymphatics in lung of CCSP-VEGF-C mouse on doxycycline from P0 to P14 (H). Sections stained for VEGFR-3 (red) and Prox1 (green). Green staining of bronchial smooth muscle does not reflect Prox1. I-J, Lung section with no pleural lymphatics in neonate on water (I) compared to subpleural lymphangiectasia (asterisks) in lung of neonate on doxycycline from P0 to P14 (J). Arrows mark surface of visceral pleura. Stained by H&E. K-L, Visceral pleura stained for mesothelin (red, arrows) has no lymphatics in control lung (K) but overlies subpleural lymphangiectasia (Prox1, green nuclei, asterisks) in lung of CCSP-VEGF-C mouse on doxycycline (L). M, Measurements of wet lung weight (mg), dry lung weight (mg), and ratio of wet-to-dry lung weight for wild-type mice (A), single transgenic mice (B, C), and CCSP-VEGF-C double transgenic mice on doxycycline from P0 to P35 (D). All three measurements in CCSP-VEGF-C mice are abnormal. *P < 0.05 vs. wild-type. Scale bar: 250 μm (D-E); 150 μm (G-J); 50 μm (K-L).