Aberrant mural cell recruitment to lymphatics leads to impaired lymphatic drainage of the lung and can be restored by inhibition of PDGFR-β–signaling. (A) Fluorescence microscopy of 488-dextran (50 μL injected intratracheally at day 28) 15 and 50 minutes after injection in lung tissue of mice treated with bleomycin (Bleo), bleomycin+AG-1296 (Bleo + AG-1296) or in healthy control lungs of PBS-treated mice, respectively. Pretracheal lymph nodes (LN) were analyzed 50 minutes after 488-dextran injection. Scale bars equal 100 μm. (B) Quantitative analysis of the fluorescence signal intensity of 488-dextran measured with ImageJ in lung tissue of Bleo-, Bleo + AG-1296–, or PBS-treated mice, 15 and 50 minutes after injection, respectively (n = 3 for each group). Error bars show SEM.