Figure 3. Hierarchical cluster analysis of differentially expressed genes in AT-MSCs from three different donors in CC1 or CC2.

The microarray data for 47,323 genes were filtered by applying two criteria for significance, P<0.05 and fold change (FC)>2, between the two cell densities (CC1 and CC2) at harvest for each MSC donor. (A) The selected data represented by hierarchical clustering of the normalized Ct of 279 genes on MSCs using individual samples (177 with increased expression, 102 with decreased expression). Each row represents a single gene, while each column represents the gene expression levels for a cell culture. The color coded gene expression levels range from red for the highest level of expression to green for the lowest. (B) Hierarchical cluster analysis of 17 differentially expressed cytokine, chemokine and growth factor genes. (C) Hierarchical cluster analysis of 33 differentially expressed proliferation-associated genes. CC1, cultures plated with an initial cell density of 200 cells/cm² and a culture duration of 7 days; CC2, cultures plated with an initial cell density of 5,000 cells/cm² and a culture duration of 7 days.