Optimization of incubation time, dmPGE₂ concentration, and modulation media in cryopreserved UCB CD34⁺ cells. (A) Microfluidic RT-PCR gene expression analysis of the top 90 signature genes after 10 μM of dmPGE₂ treatment at 37°C incubated for 0 to 240 minutes. The heat map shows log₂ fold changes in expression levels relative to vehicle control treatments of the same time. (B) Microfluidic RT-PCR gene expression analysis of the top 90 signature genes after 120 minutes at 37°C with varying dmPGE₂ concentrations. The heat map shows log₂ fold changes in expression levels relative to vehicle control treatments. (C) Genome-wide expression analysis on Affymetrix U133 plus 2.0 GeneChips of human UCB CD34⁺ cells treated with 10 µM of dmPGE₂ for 2 hours at 37°C in 8% LMD and 5% HSA or StemSpan-SFEM. RMA log₂ normalized expression levels of expression for cells treated with dmPGE₂ (y-axis) in comparison with vehicle-treated cells (x-axis). There were 99 and 297 probe sets (red) with expression levels changing greater (or less) than fourfold due to dmPGE₂ treatment in LMD/HSA and StemSpan-SFEM, respectively. (D) Fold increase of homed CD34⁺ cells over control (vehicle-treated) after incubation with 10 µM of dmPGE₂ for 2 hours at 37°C in LMD/HSA (green) and StemSpan-SFEM (red) (t test, P = .03).