Overview and correlation of transcriptomic and proteomic data sets. A: overlap of 3,320 pairs of mRNA/proteins is shown from combined human lung transcriptomic and proteomic data [n = 3, human lung at 20 mo, sorted endothelial (Endo), epithelial (Epi), immune, and mesenchymal (Mes) cells] using a Venn diagram. B: principle component analysis (PCA) of human lung transcriptomic and proteomic data (color by cell types and shape by omics types). C: hierarchical clustering of transcriptomic and proteomic data and cell-cell correlation heatmap. rs, Spearman's rank correlation coefficient.