Page 331 - 2014 Printable Abstract Book
P. 331
(PS6-12) Circulating interleukin-18 as a biomarker of total-body radiation exposure in mice, minipigs,
and nonhuman primates. Cam T. Ha, Doctoral; Xiang-Hong Li, Master; Dadin Fu, Doctoral; Maria Moroni,
Doctoral; Carolyn Fisher, Doctoral; Venkataraman Srinivasan, Doctoral; and Mang Xiao, MD
Armed Forces Radiation Research Institute, Bethesda, MD
Introduction: We aim to develop a rapid, easy-to-use, inexpensive and accurate radiation dose-
assessment assay that tests easily obtained samples (e.g., blood) to triage and track radiological casualties,
and to evaluate the radioprotective and therapeutic effects of radiation countermeasures.
Methods: In the present study, we evaluated the levels of the interleukin (IL)-1 family cytokines, IL-1β, IL-
18 and IL-33 as well as their secondary cytokines’ expression and secretion in CD2F1 mouse bone marrow
(BM), spleen, thymus and serum in response to total-body γ-irradiation (TBI) from sublethal to lethal doses
(8, 10, and 12 Gy) at different time points using the enzyme-linked immune sorbent assay (ELISA),
immunoblotting, and cytokine antibody array. In addition, the radiation-induced IL-18 in serum and
plasma samples from NHPs and minipigs were also evaluated. Results: Our data identified increases of IL-
1β, IL-18, and/or IL-33 in mouse thymus, spleen and BM cells after TBI. However, levels of these cytokines
varied in different tissues in response to the same dose of radiation at indicated time points. In
comparison with mouse tissues, IL-18 in mouse serum but not IL-1β or IL-33 was elevated significantly and
stably up to 9 days after TBI in a radiation dose-dependent manner. The increased levels of IL-18 in mouse
serum were observed on day 1 after irradiation and continually up-regulated and reached a peak on day
3 with 5.5-, 10- and 12-fold increases after 8 Gy, 10 Gy, and 12 Gy compared to serum samples from sham-
irradiated mice. We further confirmed our finding in total-body irradiated NHPs and minipigs, and
demonstrated that radiation significantly enhanced IL-18 in serum from NHPs 2-4 days post-irradiation
and in minipig plasma 1-3 days post-irradiation. Conclusion: The present study provides a novel method
for determining radiation injury by quantitation of circulating IL-18 in different animal species using ELISA.
Our results suggest that elevated levels of circulating IL-18 after radiation proportionally reflect the
radiation dose and severity of radiation injury and may be used both as a potential biomarker for triage
and also to track casualties after radiological accidents as well as for therapeutic radiation exposure.
(PS6-13) Time-dependent inhibition of pan-inflammatory cytokines mitigates radiation-induced skin
injury in mice. Kenneth A. Jenrow, PhD; Stephen L. Brown, PhD; Andrew Kolozsvary, M.S.; Karen
Lapanowski, BS; and Jae Ho Kim, MD PhD; Henry Ford Hospital, Detroit, MI
Radiation injury to skin poses substantial morbidity risks in the curative treatment of cancers and
is also of concern in the context of radiological attack or nuclear accident scenarios. Late effects are most
severe and are characterized by sub-cutaneous fibrosis and morbidity. Recent reports suggest that the
pathogenesis results from chronically impaired recovery of stromal stem cells and tissue repair caused by
long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines. These
experiments assess the potential of MW01-2-151SRM (MW-151), a novel small-molecule inhibitor of
microglial activation and associated proinflammatory cytokine/chemokine production, as a mitigator of
radiation-induced skin injury. C57BL/6 mice received focal irradiation of the right hind leg at a dose of
30Gy. Therapy was initiated either on day 3, day 7, or day 14 post-irradiation and maintained subsequently
for 21 days via intraperitoneal injections administered three times per week. The primary end point was
skin injury, assessed three times a week for at least 2 months and scored using a semi-quantitative scale.
Secondary endpoints measured at selected times included histology and immunofluorescence labeling of
329 | P a g e
and nonhuman primates. Cam T. Ha, Doctoral; Xiang-Hong Li, Master; Dadin Fu, Doctoral; Maria Moroni,
Doctoral; Carolyn Fisher, Doctoral; Venkataraman Srinivasan, Doctoral; and Mang Xiao, MD
Armed Forces Radiation Research Institute, Bethesda, MD
Introduction: We aim to develop a rapid, easy-to-use, inexpensive and accurate radiation dose-
assessment assay that tests easily obtained samples (e.g., blood) to triage and track radiological casualties,
and to evaluate the radioprotective and therapeutic effects of radiation countermeasures.
Methods: In the present study, we evaluated the levels of the interleukin (IL)-1 family cytokines, IL-1β, IL-
18 and IL-33 as well as their secondary cytokines’ expression and secretion in CD2F1 mouse bone marrow
(BM), spleen, thymus and serum in response to total-body γ-irradiation (TBI) from sublethal to lethal doses
(8, 10, and 12 Gy) at different time points using the enzyme-linked immune sorbent assay (ELISA),
immunoblotting, and cytokine antibody array. In addition, the radiation-induced IL-18 in serum and
plasma samples from NHPs and minipigs were also evaluated. Results: Our data identified increases of IL-
1β, IL-18, and/or IL-33 in mouse thymus, spleen and BM cells after TBI. However, levels of these cytokines
varied in different tissues in response to the same dose of radiation at indicated time points. In
comparison with mouse tissues, IL-18 in mouse serum but not IL-1β or IL-33 was elevated significantly and
stably up to 9 days after TBI in a radiation dose-dependent manner. The increased levels of IL-18 in mouse
serum were observed on day 1 after irradiation and continually up-regulated and reached a peak on day
3 with 5.5-, 10- and 12-fold increases after 8 Gy, 10 Gy, and 12 Gy compared to serum samples from sham-
irradiated mice. We further confirmed our finding in total-body irradiated NHPs and minipigs, and
demonstrated that radiation significantly enhanced IL-18 in serum from NHPs 2-4 days post-irradiation
and in minipig plasma 1-3 days post-irradiation. Conclusion: The present study provides a novel method
for determining radiation injury by quantitation of circulating IL-18 in different animal species using ELISA.
Our results suggest that elevated levels of circulating IL-18 after radiation proportionally reflect the
radiation dose and severity of radiation injury and may be used both as a potential biomarker for triage
and also to track casualties after radiological accidents as well as for therapeutic radiation exposure.
(PS6-13) Time-dependent inhibition of pan-inflammatory cytokines mitigates radiation-induced skin
injury in mice. Kenneth A. Jenrow, PhD; Stephen L. Brown, PhD; Andrew Kolozsvary, M.S.; Karen
Lapanowski, BS; and Jae Ho Kim, MD PhD; Henry Ford Hospital, Detroit, MI
Radiation injury to skin poses substantial morbidity risks in the curative treatment of cancers and
is also of concern in the context of radiological attack or nuclear accident scenarios. Late effects are most
severe and are characterized by sub-cutaneous fibrosis and morbidity. Recent reports suggest that the
pathogenesis results from chronically impaired recovery of stromal stem cells and tissue repair caused by
long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines. These
experiments assess the potential of MW01-2-151SRM (MW-151), a novel small-molecule inhibitor of
microglial activation and associated proinflammatory cytokine/chemokine production, as a mitigator of
radiation-induced skin injury. C57BL/6 mice received focal irradiation of the right hind leg at a dose of
30Gy. Therapy was initiated either on day 3, day 7, or day 14 post-irradiation and maintained subsequently
for 21 days via intraperitoneal injections administered three times per week. The primary end point was
skin injury, assessed three times a week for at least 2 months and scored using a semi-quantitative scale.
Secondary endpoints measured at selected times included histology and immunofluorescence labeling of
329 | P a g e
