Fig 1. Comparison of native and decellularized rat lungs.

(A) After decellularization using the H₂O-SDC protocol, no cellular remnants were observed while the alveolar architecture and extracellular matrix proteins are well-preserved as shown in histological and ultrastructural analyses (SEM, TEM). Conservation of the alveolar-capillary basement membrane was verified using SEM and TEM. (B) Quantification of the percentage of airspace revealed no difference between decellularized and native lungs. (C) DNA content was significantly reduced after decellularization (p = 0.04, Wilcoxon rank sum test). (D-E) Higher collagen concentration was found in the acellular scaffold, while elastin was maintained at similar levels to native lung tissue. Scale bars in histological images: 50 μm; scale bars in SEM images: 10 μm, scale bars in TEM images: 500 nm; data in B-E are presented as arithmetic means ± SEM; *p<0.05, Kruskal-Wallis test; n = 5.