Figure 2.

Intranasal delivery of mesenchymal stromal cells (MSCs) restores lung alveolarization. Hematoxylin and eosin stained lung sections show the characteristic simplification of lung alveolarization (larger, but fewer airspaces) in the hyperoxic injured bronchopulmonary dysplasia group (BPD). Using mean linear intercept as a surrogate for lung alveolar growth, intranasal delivery of MSCs fully restored lung architecture. Findings from alveolar tissue distribution corroborate histologic and mean linear intercept findings. Measurements expressed as mean ± SEM and included all 32 animals. RA, room air; Veh, vehicle. Mean linear intercepts: *P < .05 compared to BPD and BPD + Veh; °P > .05 compared to RA. Scale bar = 100 μm. Alveolar tissue distribution: *P < .05 compared to BPD and BPD + Veh, °P < .05 compared to RA