Figure 6. AMP cells generate airway smooth muscle following airway epithelial injury by naphthalene.
(A) Axin2+ cells (red) are the predominant Axin2 lineage residing near the airway smooth muscle (ASM-brown). Axin2+/Pdgfrα+ cells (blue) comprise a small (42%) of the overall Axin2+ cells surrounding the airways. In the naphthalene injury model airway epithelial cells are selectively ablated and a Wnt-dependent ASM proliferative response occurs. (B and C) Lineage traced Axin2+ cells, EYFP-positive and αSMA was analyzed by immunostaining and quantified. (D and E) Lineage traced Pdgfrα+ cells, EYFP+ and Acta2 was analyzed by immunostaining and quantified. (F) Model diagram indicating that the Axin2+ AMP lineage generates both parabronchial smooth muscle and myofibroblasts after injury. Representative images are shown from n=3 mice per treatment group. Error bars are means ± SEM. *=p<0.05 and ***=p<0.001 by U-test. Aw=airway. Scale bars, low magnification =50µm, high magnification =10 µM.