Page 225 - 2014 Printable Abstract Book
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euthanized at 0h, 1day (d), 4d and 7d and segments of proximal jejunum, lung, and peripheral blood
samples were procured, while for gut permeability assay at day 4, 10Gy TBI was used. Changes in lethality,
intestinal permeability, intestinal tight junction related proteins, and peripheral blood counts were
assessed. Results: Survival studies in eNOS-deficient and control mice revealed decreased
radiosensititivity in eNOS-/- mice. Protection by GT3 was partly eNOS-dependent. Interestingly,GT3
reduced post-TBI increase in intestinal Claudin-2 level in WT both at the mRNA (D1) and protein level (D1
and D4), while KO showed a decreased expression only at mRNA level (D1). However, by day 4, Claudin-2
mRNA levels were almost at baseline both in WT and KO. In contrast, Claudin-4 mRNA level was
significantly increased (p= 0.02) in KO only at D1 post-TBI. However, by day 4, both WT and KO showed
significant reduction. Further, GT3 reduced intestinal permeability in both WT and KO at day 4 post-TBI.
Conclusion: Taken together, these data suggest that eNOS may be involved, at least in part, in ameliorating
radiation-induced gut hyperpermeability, BH4 should be further explored as a potential therapeutic target
in the regulation of radiation-induced vascular dysfunction.
(PS3-65) Engraftment of human umbilical cord blood cells in mice following total body irradiation is
1
1
enhanced by hyperbaric oxygen. Omar S. Aljitawi, MD ; Yinghua Xiao, MS ; Jeff D. Eskew, PhD ; Nikhil K.
1
1
1
1
1
1
Parelkar, PhD ; Megan Swink ; Jeff Radel, PhD ; Tara L. Lin, MD ; Johnathan D. Mahnken, PhD ; Joseph P.
2
McGuirk, MD ; George Vielhauer, PhD ; Hal E. Broxmeyer, PhD ; Bruce F. Kimler, PhD ; University of
1
1
1
2
Kansas Medical Center, Kansas City, KS and Indiana University School of Medicine, Indianapolis, IN
1
Background: Umbilical cord blood (UCB) is a viable option for allogeneic transplants in the
aftermath of a radiation emergency. However, due to the limited cell doses available there is often
delayed hematopoietic cell engraftment and thus failure of the transplant. A mouse model was used to
evaluate whether hyperbaric oxygen (HBO) would improve engraftment of human UCB stem/progenitor
cells following hematopoietic suppression. Materials/Methods: Immunodeficient NOD scid gamma (NSG)
mice received total body irradiation to a sublethal dose (2.7 Gy, Cs-137, 4.5 Gy/min). At 18 hr, mice were
either maintained under normoxic conditions or received HBO (2 hr at 100% oxygen, 2.5 atmospheres
5
absolute). All mice were infused 4 hr later via tail vein injection with 1x10 CD34+ human UCB cells. The
CD34+ cells had been transduced with a lentivirus carrying luciferase gene to allow in vivo imaging (IVIS
Spectrum). Mice were sacrificed at one of nine times post-transplant to document retention (0-3 days) or
engraftment (1 week to 4 months) in peripheral blood, spleen and bone marrow, with assessment of
myeloid,B-cell, and T-cell subsets by flow cytometry. Results: Addition of HBO resulted in significantly
improved retention and engraftment of human UCB cells in bone marrow, peripheral blood, and spleen.
In addition, HBO significantly improved engraftment of myeloid (CD33+) and B-cell (CD19+) subsets. The
effects of HBO were more pronounced toward later time points of 3 and 4 months. In vivo imaging
demonstrated that HBO mice had significantly higher bioluminescence values in the thorax, especially
within 3 hr of transfusion. Conclusion: Hyperbaric oxygen treatment may be a useful adjuvant to umbilical
cord blood transfusion for mitigating the effects of total body irradiation.
(PS3-66) Inactivation of NADPH oxidases NOX4 and NOX5 protects from ionizing radiation-induced DNA
1
1
1
1
damage. Urbain S. Weyemi, PhD. ; Christophe E. Redon, PhD. ; Towqir Aziz ; Daisuke Maeda, PhD. ; Palak
1
2
2
1
R. Parekh, PhD. ; Michael Y. Bonner, BS ; Jack L. Arbiser, MD, PhD. ; and William M. Bonner, PhD. ; NIH,
1
Bethesda, MD and Emory University, Atlanta, GA
2
223 | P a g e
samples were procured, while for gut permeability assay at day 4, 10Gy TBI was used. Changes in lethality,
intestinal permeability, intestinal tight junction related proteins, and peripheral blood counts were
assessed. Results: Survival studies in eNOS-deficient and control mice revealed decreased
radiosensititivity in eNOS-/- mice. Protection by GT3 was partly eNOS-dependent. Interestingly,GT3
reduced post-TBI increase in intestinal Claudin-2 level in WT both at the mRNA (D1) and protein level (D1
and D4), while KO showed a decreased expression only at mRNA level (D1). However, by day 4, Claudin-2
mRNA levels were almost at baseline both in WT and KO. In contrast, Claudin-4 mRNA level was
significantly increased (p= 0.02) in KO only at D1 post-TBI. However, by day 4, both WT and KO showed
significant reduction. Further, GT3 reduced intestinal permeability in both WT and KO at day 4 post-TBI.
Conclusion: Taken together, these data suggest that eNOS may be involved, at least in part, in ameliorating
radiation-induced gut hyperpermeability, BH4 should be further explored as a potential therapeutic target
in the regulation of radiation-induced vascular dysfunction.
(PS3-65) Engraftment of human umbilical cord blood cells in mice following total body irradiation is
1
1
enhanced by hyperbaric oxygen. Omar S. Aljitawi, MD ; Yinghua Xiao, MS ; Jeff D. Eskew, PhD ; Nikhil K.
1
1
1
1
1
1
Parelkar, PhD ; Megan Swink ; Jeff Radel, PhD ; Tara L. Lin, MD ; Johnathan D. Mahnken, PhD ; Joseph P.
2
McGuirk, MD ; George Vielhauer, PhD ; Hal E. Broxmeyer, PhD ; Bruce F. Kimler, PhD ; University of
1
1
1
2
Kansas Medical Center, Kansas City, KS and Indiana University School of Medicine, Indianapolis, IN
1
Background: Umbilical cord blood (UCB) is a viable option for allogeneic transplants in the
aftermath of a radiation emergency. However, due to the limited cell doses available there is often
delayed hematopoietic cell engraftment and thus failure of the transplant. A mouse model was used to
evaluate whether hyperbaric oxygen (HBO) would improve engraftment of human UCB stem/progenitor
cells following hematopoietic suppression. Materials/Methods: Immunodeficient NOD scid gamma (NSG)
mice received total body irradiation to a sublethal dose (2.7 Gy, Cs-137, 4.5 Gy/min). At 18 hr, mice were
either maintained under normoxic conditions or received HBO (2 hr at 100% oxygen, 2.5 atmospheres
5
absolute). All mice were infused 4 hr later via tail vein injection with 1x10 CD34+ human UCB cells. The
CD34+ cells had been transduced with a lentivirus carrying luciferase gene to allow in vivo imaging (IVIS
Spectrum). Mice were sacrificed at one of nine times post-transplant to document retention (0-3 days) or
engraftment (1 week to 4 months) in peripheral blood, spleen and bone marrow, with assessment of
myeloid,B-cell, and T-cell subsets by flow cytometry. Results: Addition of HBO resulted in significantly
improved retention and engraftment of human UCB cells in bone marrow, peripheral blood, and spleen.
In addition, HBO significantly improved engraftment of myeloid (CD33+) and B-cell (CD19+) subsets. The
effects of HBO were more pronounced toward later time points of 3 and 4 months. In vivo imaging
demonstrated that HBO mice had significantly higher bioluminescence values in the thorax, especially
within 3 hr of transfusion. Conclusion: Hyperbaric oxygen treatment may be a useful adjuvant to umbilical
cord blood transfusion for mitigating the effects of total body irradiation.
(PS3-66) Inactivation of NADPH oxidases NOX4 and NOX5 protects from ionizing radiation-induced DNA
1
1
1
1
damage. Urbain S. Weyemi, PhD. ; Christophe E. Redon, PhD. ; Towqir Aziz ; Daisuke Maeda, PhD. ; Palak
1
2
2
1
R. Parekh, PhD. ; Michael Y. Bonner, BS ; Jack L. Arbiser, MD, PhD. ; and William M. Bonner, PhD. ; NIH,
1
Bethesda, MD and Emory University, Atlanta, GA
2
223 | P a g e
