fig3

Figure 3. BMSC-secreted factors after expansion in the analyzed media. (A) Principal component analysis of the ln(x) transformed pg/10⁶ BMSCs values for the detected factors. The X- and Y-axes represent principal components 1 and 2 that explain 59.9% and 40.1% of the total variance, respectively. F stands for FBS, P for hPL, and S/X for serum/xeno free. “r” denotes the Spearman correlation coefficient; (B) Heatmap of hierarchical clustering analysis of the ln(x) transformed pg/10⁶ BMSCs values of detected factors, with sample clustering tree shown at the top. The color scale indicates absolute expression levels: red shades = high expression levels and blue shades = low expression levels. F, P, and S/X represent the same media conditions as in panel A; (C) Functional association network of the identified secreted factors, generated using the online tool STRING. Blue connections are for proteins with known interactions based on curated databases; violet connections for proteins with experimentally determined interactions. Empty nodes, proteins with unknown 3D structure; filled nodes, proteins with known or predicted 3D structure; (D) Functional association network of secreted factors in the first quartile of abundance, also generated using the online tool STRING. Color coding and graphic elements are consistent with (C). BMSCs: Bone marrow-derived mesenchymal stromal cells; F: fetal bovine serum; P: platelet lysate; S/X: serum/xeno free.