Project description: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 at 25 and 37 deg C could increase biological responses. Isolated human CD34+ cells from umbilical cord blood were incubated ex vivo in Stem Span (SS) media evaluating five concentrations of 16,16-dmPGE2 (0.1uM, 1uM, 10uM, 50uM, and 100uM) or Vehicle (DMSO) for 2 hours at 25 or 37 deg C. Total RNA was isolated post incubation and analyzed on Affymetrix microarrays for pathway activation.
Project description:Transplantation with low numbers of hematopoietic stem cells (HSCs), found in many of the publically accessible cryopreserved umbilical cord blood (UCB) units, leads to delayed time to engraftment, high graft failure rates, and early mortality in many patients. A chemical screen in zebrafish identified the prostaglandin compound, 16,16 dimethyl prostaglandin E2 (dmPGE2), to be a critical regulator of hematopoietic stem cell homeostasis. We hypothesized that an ex vivo modulation with dmPGE2 prior to transplantation would lead to enhanced engraftment by increasing the “effective” dose of hematopoietic stem cells (HSCs) in cord blood. A phase I trial of reduced-intensity double UCB transplantation was performed to evaluate safety, rates of engraftment and fractional chimerism of dmPGE2 enhanced UCB units. To explore potential causes of the lack of enhanced efficacy in the first cohort, we characterized HSCs to determine whether the prostaglandin pathway was being activated under the ex vivo incubation conditions (4°C, 10µM dmPGE2, 60 minutes). Incubation conditions were identified (37°C, 10µM dmPGE2, 120 minutes) that maximize the activation of the prostaglandin pathway by dmPGE2 in human CD34+ cells. Isolated human CD34+ from umbilical cord blood were incubated ex vivo in Stem Span media with 10uM 16,16-dmPGE2 or DMSO. Two treatment conditions were evaluated (4 deg C for 1 hour, 37 deg C for 2 hours) with either 3 or 7 biological replicates at each condition. Total RNA was isolated post incubation and analyzed on Affymetrix microarrays for pathway activation.
Project description: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 at 25 and 37 deg C could increase biological responses.
Project description: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 determine the optimal ex vivo modulation conditions (e.g., temperature and media) for use in a clinical setting by measured pathway induced expression changes. Isolated human CD34+ from umbilical cord blood were incubated ex vivo in Stem Span (SS) media evaluating three treatment temperatures (4 deg C, 25 deg C, and 37 deg C) with 10uM 16,16-dmPGE2 or Vehicle (DMSO) for 2 hours. To evaluate optimal media, similar CD34+ cells were incubated ex vivo in either Stem Span-SFEM (SS) media or 8% Low Molecular Weigh Dextran 40/5% HSA solution (LMD/HSA) with 10uM 16,16-dmPGE2 or Vehicle (DMSO) for 2 hours at 37 deg C. Total RNA was isolated post incubation and analyzed on Affymetrix microarrays for pathway activation.
Project description: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.
Project description:Transplantation with low numbers of hematopoietic stem cells (HSCs), found in many of the publically accessible cryopreserved umbilical cord blood (UCB) units, leads to delayed time to engraftment, high graft failure rates, and early mortality in many patients. A chemical screen in zebrafish identified the prostaglandin compound, 16,16 dimethyl prostaglandin E2 (dmPGE2), to be a critical regulator of hematopoietic stem cell homeostasis. We hypothesized that an ex vivo modulation with dmPGE2 prior to transplantation would lead to enhanced engraftment by increasing the “effective” dose of hematopoietic stem cells (HSCs) in cord blood. A phase I trial of reduced-intensity double UCB transplantation was performed to evaluate safety, rates of engraftment and fractional chimerism of dmPGE2 enhanced UCB units. To explore potential causes of the lack of enhanced efficacy in the first cohort, we characterized HSCs to determine whether the prostaglandin pathway was being activated under the ex vivo incubation conditions (4°C, 10µM dmPGE2, 60 minutes). Incubation conditions were identified (37°C, 10µM dmPGE2, 120 minutes) that maximize the activation of the prostaglandin pathway by dmPGE2 in human CD34+ cells.
Project description: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.