Prostaglandin dose response on hematopoietic stem cells (4 deg C)

Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) for use in allogeneic transplantation. Key advantages of UCB are rapid availability and less stringent requirements for HLA matching. However, UCB contains an inherently limited HSC count, which is associated with delayed time to engraftment, high graft failure rates and early mortality. 16,16 dimethyl prostaglandin E2 (dmPGE2) was previously identified to be a critical regulator of HSC homeostasis and we hypothesized that a brief ex vivo modulation could improve patient outcomes by increasing the “effective dose” of HSCs. Molecular profiling with Affymetrix GeneChips were used to evaluate if increasing the concentration of prostaglandin could compensate for the reduced biological responses observed with incubations at 4 deg C. Isolated human CD34+ from umbilical cord blood were incubated ex vivo in Stem Span (SS) media evaluating three concentrations of 16,16-dmPGE2 (10uM, 50uM, and 100uM) or Vehicle (DMSO) for 2 hours at 4 deg C. To evaluate if increasing the concentration of prostaglandin could compensate for the reduced biological responses observed with incubations at 4 deg C. Total RNA was isolated post incubation and analyzed on Affymetrix microarrays for pathway activation.