wECM, airECM, aECM, and vECM samples were obtained from six individual ND human lungs for proteomic analysis (n=6). (A) Schematic depicting samples utilized for proteomic analysis. (B) PCA plot demonstrating similarity of ECM protein composition amongst region-specific samples. Each data point represents the relative abundance (%) of all individual ECM proteins (normalized to abundance of total ECM composition within each respective sample). (C) Heatmap of top 25 normalized ECM proteins across all decellularized lung regions.(D) Ratio of mean basement membrane composition from decellularized lung specific regions. (E) Comparison of normalized individual ECM proteins across lung regions. Bars indicate mean +/− SEM, n=6 biological replicates; *p<0.05, **p<0.01 using Dunn’s method. Statistical trends are identified if 0.05≤p<0.1. (F) Qualitative Venn diagram depicting differences in region-specific ECM composition of pooled samples.