Dataset Information

Imaging Macrophage Accumulation in a Murine Model of Chronic Pancreatitis with 125I-Iodo-DPA-713 SPECT/CT.

ABSTRACT: Pancreatitis remains a diagnostic challenge in patients with mild to moderate disease, with current imaging modalities being inadequate. Given the prominent macrophage infiltration in chronic pancreatitis, we hypothesized that 125I-iodo-DPA-713, a small-molecule radiotracer that specifically targets macrophages, could be used with SPECT/CT to image pancreatic inflammation in a relevant experimental model. Methods: Chronic pancreatitis was induced with cerulein in C57BL/6 mice, which were contrasted with saline-injected control mice. The animals were imaged at 7 wk after induction using N,N-diethyl-2-(2-(3-125I-iodo-4-methoxyphenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide (125I-iodo-DPA-713) SPECT/CT or 18F-FDG PET/CT. The biodistribution of 125I-iodo-DPA-713 was determined under the same conditions, and a pair of mice was imaged using a fluorescent analog of 125I-iodo-DPA-713, DPA-713-IRDye800CW, for correlative histology. Results: Pancreatic 125I-iodo-DPA-713 uptake was significantly higher in treated mice than control mice (5.17% ± 1.18% vs. 2.41% ± 0.34% injected dose/g, P = 0.02), as corroborated by imaging. Mice imaged with 18F-FDG PET/CT showed cerulein-enhanced pancreatic uptake in addition to a moderate signal from healthy pancreas. Near-infrared fluorescence imaging with DPA-713-IRDye800CW showed strong pancreatic uptake, focal liver uptake, and gastrointestinal uptake in the treated mice, whereas the control mice showed only urinary excretion. Ex vivo fluorescence microscopy revealed a large influx of macrophages in the pancreas colocalizing with the retained fluorescent probe in the treated but not the control mice. Conclusion: These data support the application of both 125I-iodo-DPA-713 SPECT/CT and DPA-713-IRDye800CW near-infrared fluorescence to delineate pancreatic, liver, or intestinal inflammation in living mice.

SUBMITTER: Foss CA

PROVIDER: S-EPMC5632737 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Imaging Macrophage Accumulation in a Murine Model of Chronic Pancreatitis with 125I-Iodo-DPA-713 SPECT/CT.

Foss Catherine A CA Liu Liansheng L Mease Ronnie C RC Wang Haofan H Pasricha Pankaj P Pomper Martin G MG

Journal of nuclear medicine : official publication, Society of Nuclear Medicine 20170518 10

Pancreatitis remains a diagnostic challenge in patients with mild to moderate disease, with current imaging modalities being inadequate. Given the prominent macrophage infiltration in chronic pancreatitis, we hypothesized that 125I-iodo-DPA-713, a small-molecule radiotracer that specifically targets macrophages, could be used with SPECT/CT to image pancreatic inflammation in a relevant experimental model. Methods: Chronic pancreatitis was induced with cerulein in C57BL/6 mice, ...[more]

PMID: 28522739

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Dataset Information

Imaging Macrophage Accumulation in a Murine Model of Chronic Pancreatitis with 125I-Iodo-DPA-713 SPECT/CT.

Publications

Imaging Macrophage Accumulation in a Murine Model of Chronic Pancreatitis with <sup>125</sup>I-Iodo-DPA-713 SPECT/CT.

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