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- Tegler, Gustaf, 1968-, et al.
(author)
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4D-PET/CT with [11C]-PK11195 and [11C]-D-deprenyl does not identify the chronic inflammation in asymptomatic abdominal aortic aneurysms
- 2013
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In: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1078-5884 .- 1532-2165. ; 45:4, s. 351-356
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Journal article (peer-reviewed)abstract
- ObjectivesThe aim of this study was to investigate the relevance of inflammation in the pathogenesis of abdominal aortic aneurysm (AAA) in vivo with two novel positron emission tomography (PET) tracers: [11C]-PK11195 which targets the translocator protein (18 kDa) expressed on macrophages and [11C]-d-deprenyl with a yet unknown target receptor expressed in chronic inflammation.DesignProspective clinical study.Materials/methodsFive patients were examined with [11C]-PK11195-positron emission tomography/computed tomography (PET/CT) and 10 with [11C]-d-deprenyl-PET/CT. Nine large AAAs (54–66 mm) scheduled for repair and six small AAA (35–44 mm). All 15 patients were male and the AAAs were all asymptomatic. Regional activity was measured as standardised uptake values (SUVs) and retention index was calculated. Biopsies were taken from the aneurysm wall for histological examinations, in the nine patients operated on.ResultsNo aortic uptake was recorded on the visual inspection, neither with [11C]-PK11195 nor with [11C]-d-deprenyl. For [11C]-PK11195 the median SUV of the AAA wall was 0.9 (range 0.8–1.0) and for [11C]-d-deprenyl, 0.7 (range 0.4–1.2). No increased uptake was seen in the aneurysmal infrarenal aorta compared with the non-aneurysmal suprarenal aorta. Histological examination of the aneurysm wall showed high inflammatory cell infiltration with lymphocytes and macrophages.ConclusionsThe chronic inflammation observed in the vessel wall was not detectable with [11C]-PK11195 and [11C]-d-deprenyl. In order to study the relevance of the inflammation in the pathogenesis of AAA in vivo other PET tracers need to be investigated.
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| 3. |
- Tegler, Gustaf, et al.
(author)
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Autoradiography screening of potential positron emission tomography tracers for asymptomatic abdominal aortic aneurysms
- 2014
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In: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 119:3, s. 229-235
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Journal article (peer-reviewed)abstract
- Objective. The aetiology and early pathophysiological mechanisms of aortic aneurysm formation are still unknown and challenging to study in vivo. Positron emission tomography (PET) is a potentially valuable instrument for non-invasive in vivo pathophysiological studies. No specific tracer to identify the pathophysiological process of aneurysmal dilatation is yet available, however. The aim of this study was to explore if different PET tracers could be useful to image aneurysmal disease. Methods and results. Human aneurysmal aortic tissue, collected during elective resection of abdominal aortic aneurysm (AAA) of asymptomatic patients, was investigated in vitro by means of autoradiography with [Ga-68]CRP-binder targeting C-reactive protein, [C-11]DAA1106 targeting translocator protein (18 kDa), [C-11]D-deprenyl with unknown target receptor, [C-11] deuterium-L-deprenyl targeting astrocytes, [F-18]fluciclatide targeting integrin alpha(V)beta(3), [Ga-68]IMP461 and bi-specific antibody TF2 052107 targeting carcinoembryonic antigen, [F-18]F-metomidate targeting mitochondrial cytochrome P-450 species in the adrenal cortex, and [F-18]vorozole targeting aromatase. Of the investigated tracers, only [F-18]fluciclatide exhibited specific binding, whereas the other PET tracers failed to show specific uptake in the investigated tissue and are probably not useful for the intended purpose. Conclusion. It seems likely that alpha(V)beta(3) integrin expression in AAA can be visualized with PET and that the alpha(V)beta(3) selective tracer, [F-18]fluciclatide, may be suitable for in vivo molecular imaging of asymptomatic AAA. Additional evaluation of [F-18]fluciclatide and alpha(V)beta(3) integrin expression in AAA will be performed in vitro as well as in vivo.
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