Comparison of 68Ga-DOTA-Siglec-9 and 18F-Fluorodeoxyribose …downloads.hindawi.com/journals/cmmi/2017/7645070.pdf · 2019-07-30 · viouslyreported68Ga-DOTA-Siglec-9[4]. 2.5. Statistical

Research ArticleComparison of 68Ga-DOTA-Siglec-9 and18F-Fluorodeoxyribose-Siglec-9 Inflammation Imaging andRadiation Dosimetry

Helena Virtanen1 Johanna M U Silvola1 Anu Autio1 Xiang-Guo Li23

Heidi Liljenbaumlck14 Sanna Hellberg1 Riikka Siitonen1 Mia Staringhle1 Meeri Kaumlkelauml1

Anu J Airaksinen3 Kerttuli Helariutta3 Tuula Tolvanen5 Tibor Z Veres6 Antti Saraste15

Juhani Knuuti15 Sirpa Jalkanen6 and Anne Roivainen145

1Turku PET Centre University of Turku Turku Finland2Turku PET Centre Abo Akademi University Turku Finland3Laboratory of Radiochemistry Department of Chemistry University of Helsinki Helsinki Finland4Turku Centre for Disease Modeling University of Turku Turku Finland5Turku PET Centre Turku University Hospital Turku Finland6MediCity Research Laboratory University of Turku Turku Finland

Correspondence should be addressed to Anne Roivainen anneroivainenutufi

Received 27 July 2017 Accepted 13 November 2017 Published 31 December 2017

Academic Editor Gaurav Malviya

Copyright copy 2017 HelenaVirtanen et alThis is an open access article distributed under theCreative CommonsAttribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a ligand of inflammation-inducible vascular adhesion protein-1 (VAP-1)We compared 68Ga-DOTA- and 18F-fluorodeoxyribose- (FDR-) labeled Siglec-9motif peptides for PET imaging of inflammationMethods Firstly we examined 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 in rats with skinmuscle inflammation We then studied18F-FDR-Siglec-9 for the detection of inflamed atherosclerotic plaques inmice and compared it with previous 68Ga-DOTA-Siglec-9results Lastly we estimated human radiation dosimetry from the rat data Results In rats 68Ga-DOTA-Siglec-9 (SUV 088 plusmn 0087)and 18F-FDR-Siglec-9 (SUV 077 plusmn 022) showed comparable (119875 = 029) imaging of inflammation In atherosclerotic mice 18F-FDR-Siglec-9 detected inflamed plaques with a target-to-background ratio (16 plusmn 0078) similar to previously tested 68Ga-DOTA-Siglec-9 (119875 = 035) Human effective dose estimates for 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9were 0024 and 0022mSvMBqrespectively Conclusion Both tracers are suitable for PET imaging of inflammation The easier production and lower cost of 68Ga-DOTA-Siglec-9 present advantages over 18F-FDR-Siglec-9 indicating it as a primary choice for clinical studies

1 Introduction

Inflammation plays role in several diseases such as rheuma-toid arthritis diabetes and atherosclerosis The early detec-tion of inflammatory foci is critical for the adequate treatmentof patients and quantitative PET imaging may provide avaluable tool for diagnosis and monitoring of the effects oftherapeutic interventions 18F-FDG is the gold standard forPET but not specific to inflammation In addition the highphysiological accumulation of 18F-FDG in heart and brain

makes it difficult to detect inflammatory foci close to theseorgans [1]

Vascular adhesion protein-1 (VAP-1) is an endothe-lial adhesion molecule which is involved in leukocytetransendothelial migration from blood into the sites ofinflammation During inflammationVAP-1 translocates fromintracellular storages on the endothelial cell surface where itcontributes leukocyte-endothelial adhesion Although VAP-1 plays important role in early phases of inflammation itsluminal expression on the endothelium will remain constant

HindawiContrast Media amp Molecular ImagingVolume 2017 Article ID 7645070 10 pageshttpsdoiorg10115520177645070

2 Contrast Media amp Molecular Imaging

Table 1 Characteristics of study animals

Sprague-Dawley skininflammation rats

LDLRminusminusApoB100100atherosclerotic mice

C57BL6N controlmice

Age (months) 22 plusmn 0051 56 plusmn 096 21 plusmn 039High fat diet (months) ND 36 plusmn 10 NDFemalemale (no) 016 154 67Weight (g) 350 plusmn 22 27 plusmn 40 24 plusmn 22In vivo PET (no) 13 2 2Ex vivo gamma counting (no) 16 19 13Ex vivo autoradiography (no) ND 12 10LDLRminusminusApoB100100 = low-density lipoprotein receptor-deficient mouse expressing only apolipoprotein B100 ND = not done no = number of investigatedanimals

if the inflammation continues which suggest VAP-1 as apromising target for both anti-inflammatory therapy andmolecular imaging of inflammation [2] The role of VAP-1in atherosclerotic inflammation is unclear VAP-1 expressionis upregulated in atherosclerotic plaques in human carotidarteries [3 4] and in the aorta of hypercholesterolemic rabbits[5] VAP-1 is also expressed in soluble form (sVAP-1) whichassociates with atherosclerosis [6 7]

We previously showed that sialic acid-binding immuno-globulin-like lectin 9 (Siglec-9) is a VAP-1 ligand and theradiolabeled peptide (CARLSLSWRGLTLCPSK) containingresidues 283ndash297 from Siglec-9 can be used for PET imagingof inflammation [4 8ndash11]

In this study we examined the detection of skinmuscleinflammation in rats comparing the utility of the Siglec-9motif peptides 68Ga-labeled 14710-tetraazacyclododecane-NN1015840N10158401015840N101584010158401015840-tetraacetic acid-conjugated 68Ga-DOTA-Sig-lec-9 and 18F-labeled fluorodeoxyribose-conjugated 18F-FDR-Siglec-9 [9] We also examined 18F-FDR-Siglec-9 up-take in inflamed atherosclerotic plaques of mice and com-pared it with previous 68Ga-DOTA-Siglec-9 results [4]Finally we used the rat PET data to estimate the human radi-ation doses for 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9

2 Materials and Methods

21 Radiochemistry 68Ga-DOTA-Siglec-9 and 18F-FDR-Sig-lec-9 were produced as previously described [8 9]

22 Animal Models Twenty-four hours before the PETstudies Sprague-Dawley rats (weight 350 plusmn 22 g 119899 = 16)were subcutaneously injected with turpentine oil (Sigma-Aldrich) to induce focal acute sterile inflammation [12]Before the injection rats were shaved on the both forelegsInflamed area on the left foreleg contained both skin andmuscle The intact contralateral side (right foreleg) was usedas a control

Six-month-old atherosclerotic low-density lipoproteinreceptor-deficient mice (weight 27 plusmn 41 g 119899 = 19) express-ing only apolipoprotein B100 (LDLRminusminusApoB100100 strain003000 JacksonLaboratory BarHarborMEUSA)were fedfor 4 months with a Western-type diet [13] Two-month-oldC57BL6Nmice (weight 24 plusmn 22 g 119899 = 13) fedwith a regularchow served as controls

All animal experiments (Table 1) were approved by thenational Animal Experiment Board in Finland and carriedout in compliance with the EU directive

23 Rat Studies Rats were divided into two groups withGroup 1 being intravenously (iv) given 68Ga-DOTA-Siglec-9(16 plusmn 29MBq 119899 = 8) andGroup 2 18F-FDR-Siglec-9 (18 plusmn 51MBq 119899 = 8) A 60min dynamic PET acquisition wasperformed on a High Resolution Research Tomograph(HRRT Siemens Medical Solutions Knoxville TN USA)The PET data were reconstructed into 5 times 60 s and 11 times 300 sframes using an ordered-subsets expectation maximization3D algorithm (OSEM3D) Quantitative PET image analysiswas performed by defining regions of interest (ROIs) withinthe inflamed area (on the left foreleg) control area (on theright foreleg) kidneys lungs heart liver and urinary bladderusing Carimas 28 software (Turku PET Centre) Resultswere expressed as standardized uptake values (SUV) andtime-activity curves SUV was calculated as a ratio of tissueradioactivity concentration (BqmL) and given radioactivitydose (Bq) divided by animalrsquos body weight

After PET imaging rats were sacrificed and varioustissues were excised and weighed and their radioactivitylevels weremeasuredwith a gamma counter (1480Wizard 310158401015840PerkinElmer Turku Finland) The ex vivo biodistributionresults were expressed as a percentage of the injected radioac-tivity dose per gram of tissue ( IDg) and target-to-background ratio

The inflamed area and control area tissue samples werefrozen cut into sections and stained with hematoxylin-eosin(HampE) for morphological evaluation

Absorbed doses of 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 were calculated with the OLINDAEXM version 10software (organ level internal dose assessment and exponen-tial modeling Vanderbilt University Nashville TN USA)which applies the MIRD schema (developed by the Med-ical Internal Radiation Dose committee of the Society ofNuclear Medicine) for radiation dose calculations in internalexposure The software includes radionuclide informationand selection of human body phantoms The residence timesderived from the rat datawere integrated as the area under thetime-activity curve The residence times were converted intocorresponding human values by multiplication with a factor

Contrast Media amp Molecular Imaging 3

to scale the organ and body weights (WBodyratWOrganrat) times(WOrganhumanWBodyhuman) where WBodyrat andWBodyhumanare the body weights of rat and human (a 70-kg male)respectively and 119882Organrat and 119882Organhuman are the organweights of rat and human (organ weights for a 70 kg male)respectively [14]

24 Mouse Studies To detect luminal expression of VAP-1mice were intravenously (iv) injected with a monoclonal ratanti-mouse VAP-1 antibody (7ndash88 1mgkg diluted in saline)[15] 10min before sacrifice Aorta samples were frozen andcut into 8120583m longitudinal sections incubated for 30min atroom temperature in the dark with a secondary goat anti-ratantibody (working dilution 5 120583gmL in phosphate-bufferedsaline (PBS) containing 5 normal mouse or human ABserum) conjugated to a fluorescent dye (Alexa Fluor 488Invitrogen Eugene OR USA) and rinsed twice in PBS for5min

In PET studies mice (19 atherosclerotic 13 controls) wereinjected with 14 plusmn 44MBq of 18F-FDR-Siglec-9 Twenty-fiveminutes after 18F-FDR-Siglec-9 injection blood was drawnby cardiac puncture and the animals were killedThe thoracicaorta was excised and rinsed in saline to remove the blood Inaddition various other tissues were excised and patted drySamples of blood and urine were collected and blood plasmawas separated by centrifugation All tissue samples wereweighed and their radioactivity levels were measured with agamma counter (Triathler 310158401015840 HidexOy Turku Finland)Theresults were expressed as IDg and target-to-backgroundratio

Autoradiography was used to study the distributionof radioactivity in the aorta in more detail as describedpreviously [13] After careful superimposition of the autora-diographs andHampE stained images the count densities of 540ROIs (185 plaques 241 normal vessel walls and 114 adven-titia) were analyzed using Tina 21 software The autoradio-graphy results were calculated as the photostimulated lumi-nescence per unit area (PSLmm2) normalized for injectedradioactivity dose and as ratios between the atheroscleroticplaque normal vessel wall and adventitia

A subset of mice (two atherosclerotic two controls) wereinjected with 47 plusmn 11MBq of 18F-FDR-Siglec-9 and imagedwith an Inveon Multimodality PETCT (Siemens Medi-cal Solutions Knoxville TN USA) Dynamic PET imageswere acquired for 60min followed by CT with a contrastagent (eXIATM160XL Binitio Biomedical Inc Ottawa ONCanada)The PET images were reconstructed with OSEM3D(frames 5 times 60 s 3 times 300 s 1 times 600 s 2 times 1800 s)

Quantitative PET image analysis was performed by defin-ing ROIs in the heart left ventricle (blood pool) and aorticarch as identified on the basis of the CT angiography by usingthe Inveon Research Workplace software (Siemens MedicalSolutions Knoxville TN USA) Time frames 10ndash20min afterinjection were used for PET quantification as previouslyreported in the samemousemodel using 68Ga-DOTA-Siglec-9 [4] The results within ROIs were expressed as SUV andtarget-to-background ratio (SUVmaxaortic archSUVmeanblood)

Finally we compared 18F-FDR-Siglec-9 results with pre-viously reported 68Ga-DOTA-Siglec-9 [4]

25 Statistical Analyses All results are expressed as meanplusmn SD Paired 2-tailed Studentrsquos 119905-tests were applied forintra-animal comparisons Nonpaired data were comparedbetween two groups using 119905-tests and between multiplegroups using ANOVAwith Tukeyrsquos correction A 119875 value lessthan 005 was considered statistically significant

3 Results

31 Radiochemistry The specific radioactivity of 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 was 70 plusmn 15 MBqnmol and 83 plusmn 33MBqnmol respectively with radiochem-ical purity being gt95 throughout the study

32 Rat Studies The turpentine oil caused focal soft-tissueinflammation with edema and leukocyte infiltration pre-dominantly neutrophils (Figure 1) and luminal VAP-1 aspreviously reported [8 16]

The inflammatory focus was clearly visualized with bothof the PET tracers and was demonstrated in the time-activitycurves of the inflamed area with the uptake kinetics of bothtracers being comparable (Figure 2) In the inflamed areathe SUVmean10ndash60min of 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 was 088 plusmn 0087 and 077 plusmn 022 respectively (119875 =029) The corresponding SUVmax10ndash60min values for 68Ga-DOTA-Siglec-9 (11 plusmn 010) and 18F-FDR-Siglec-9 (11 plusmn0097) were also close to each other (119875 = 047) Bothtracers peaked about 10min after the iv bolus injectionwith a slow decrease thereafter The inflammation-to-bloodratios10ndash60min of 68Ga-DOTA-Siglec-9 (15 plusmn 033) and 18F-FDR-Siglec-9 (17 plusmn 051) were also comparable (119875 = 054)Uptake in the heart liver kidneys and urinary bladder wasclearly visible with both tracers (Figure 2)

Ex vivo gamma counting at 60min after injectiondemonstrated that 18F-FDR-Siglec-9 uptake was significantlyhigher than 68Ga-DOTA-Siglec-9 uptake in several organsincluding inflamed and control areas The difference wasparticularly notable in the liver pancreas heart and kidneys(Table 2) Only in the spleen was the uptake of 68Ga-DOTA-Siglec-9 significantly higher than that of 18F-FDR-Siglec-9Although the uptake of 18F-FDR-Siglec-9 in inflamed area(019 plusmn 0053 IDg) was significantly higher (119875 = 0013)than that of 68Ga-DOTA-Siglec-9 (012 plusmn 0032 IDg) theinflammation-to-blood and inflamed-to-control area ratios(18F-FDR-Siglec-9 13 plusmn 016 and 20 plusmn 070 68Ga-DOTA-Siglec-9 14 plusmn 042 and 25 plusmn 054) were similar (119875 = 067 and119875 = 018 resp)

Extrapolation from the rat PET data suggested esti-mated human effective doses for a 70 kg man of 0024 plusmn00041mSvMBq for 68Ga-DOTA-Siglec-9 and 0022 plusmn00042mSvMBq for 18F-FDR-Siglec-9 The most criticalorgans were the urinary bladder wall with 68Ga-DOTA-Siglec-9 (020 plusmn 0087mSvMBq) and kidneys with 18F-FDR-Siglec-9 (029 plusmn 013mSvMBq) (Tables 3 and 4)


Table 2 Ex vivo biodistribution ( IDg) of 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 at 60min after injection in rats with skinmuscleinflammation

Organ 68Ga-DOTA-Siglec-9 18F-FDR-Siglec-9 119875 valuelowast

Control area 0051 plusmn 00063 011 plusmn 0056 0015Inflamed area 012 plusmn 0032 019 plusmn 0053 0013Adipose tissue BAT 0024 plusmn 0026 0049 plusmn 0019 012Adipose tissue WAT 0027 plusmn 0014 0017 plusmn 00041 0090Blood 0099 plusmn 0040 012 plusmn 0023 033Bone (femoral) 0020 plusmn 00089 0017 plusmn 0010 067Bone marrow 0039 plusmn 0012 0056 plusmn 0011 0022Brain 00062 plusmn 00049 0010 plusmn 00030 0083Heart 0030 plusmn 0011 0048 plusmn 0010 00038Kidneys 28 plusmn 18 14 plusmn 99 00053Liver 032 plusmn 016 068 plusmn 012 000014Lungs 0079 plusmn 0035 011 plusmn 0028 0059Muscle 0019 plusmn 00091 0021 plusmn 00067 068Pancreas 0024 plusmn 00024 0048 plusmn 0011 000062Plasma 013 plusmn 0015 023 plusmn 0087 0087Small intestine 0060 plusmn 0016 0091 plusmn 0029 0051Spleen 019 plusmn 0110 0060 plusmn 0012 00048Testis 0035 plusmn 0031 0046 plusmn 0022 045Urine 24 plusmn 11 23 plusmn 14 093 IDg = percentage of injected radioactivity dose per gram of tissue BAT=brown adipose tissue WAT = white adipose tissue lowastUnpaired 2-tailed Studentrsquos119905-test

Figure 1 Inflammation of skinmuscle in a rat at 24 hours after subcutaneous injection of turpentine oil Hematoxylin-eosin staining of a10 120583m cryosection reveals edema and leukocyte infiltration predominantly neutrophils

33 Mouse Studies The LDLRminusminusApoB100100 mice demon-strated atherosclerotic plaques especially in the aortic archwhile the C57BL6Nmice showed no evidence of atheroscle-rosis Furthermore the LDLRminusminusApoB100100 atheroscleroticlesions were VAP-1 positive whereas normal vessel walls inthe aortas of C57BL6Nmice were VAP-1-negative (Figure 3)18F-FDR-Siglec-9 PETCT imaging of atherosclerotic

mice showed plaques in the aortic arch with a target-to-background ratio of 16 plusmn 0078 at 10ndash20min after injection(Figure 4(a)) This ratio was similar to that reported previ-ously for 68Ga-DOTA-Siglec-9 (17 plusmn 022 119875 = 035)

According to ex vivo gamma counting the aortic uptakeof 18F-FDR-Siglec-9 was significantly higher (119875 = 00015)

in the LDLRminusminusApoB100100 mice (093 plusmn 038 IDg) thanin the C57BL6N mice (052 plusmn 023 IDg Table 5) andcomparable to the uptake of 68Ga-DOTA-Siglec-9 (083 plusmn033 IDg 119875 = 038)

Autoradiography of aortic cryosections further con-firmed 18F-FDR-Siglec-9 accumulation in atheroscleroticplaques with a plaque-to-healthy vessel wall ratio of 19 plusmn023 (119875 lt 0001) and plaque-to-adventitia ratio of 22 plusmn 053(119875 lt 0001) In control mice the uptake of 18F-FDR-Siglec-9in healthy vessel wall was similar to that in the atheroscleroticmice (Figure 4) However the plaque-to-healthy vessel wallratioswere higherwith 68Ga-DOTA-Siglec-9 (21 plusmn 043) thanwith 18F-FDR-Siglec-9 (119875 = 0038)


High

LowKidneysUrinary bladder

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

0

3

6

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

BloodControl areaInflamed area

LiverLungs

(a)

High

Low

0

3

6

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)

KidneysUrinary bladder


LiverLungs

(b)

18-FDR-Siglec-9

68a-DOTA-Siglec-9

0

05

10

15

20

25

Infla

med

area

-to-b

lood

ratio

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

(c)

Figure 2 PET images and time-activity curves of rats with skinmuscle inflammation (arrow) imaged with (a) 68Ga-DOTA-Siglec-9 (119899 = 5)or (b) 18F-FDR-Siglec-9 (119899 = 8) and (c) comparison of their target-to-blood kinetics


Table 3 Normalized number of disintegrations (hours) in source organs extrapolated from the rat PET data


Heart wall 00029 plusmn 000072 00026 plusmn 00010 055Kidneys 0093 plusmn 0081 047 plusmn 021 00032Liver 0033 plusmn 00097 011 plusmn 0043 00027Lungs 00026 plusmn 00011 00029 plusmn 00011 062Muscle 0054 plusmn 00088 0081 plusmn 0042 017Urinary bladder wall 017 plusmn 0076 015 plusmn 0070 070Total body 13 plusmn 0085 18 plusmn 032 00042lowastUnpaired 2-tailed Studentrsquos 119905-test

Table 4 Human dose equivalent estimates (mSvMBq) extrapolated from the rat PET data


Adrenals 0014 plusmn 00012 0020 plusmn 00029 00011Brain 0012 plusmn 000077 0010 plusmn 00018 0064Breasts 0011 plusmn 000064 00086 plusmn 00011 00036Gallbladder wall 0014 plusmn 000065 0017 plusmn 00014 000022Heart wall 00083 plusmn 00010 00085 plusmn 000045 052Kidneys 015 plusmn 012 029 plusmn 013 0070Liver 0012 plusmn 00024 0021 plusmn 00061 0014Lower large intestine wall 0015 plusmn 000077 0014 plusmn 000091 0067Lungs 00044 plusmn 000054 00062 plusmn 000016 lt00001Muscle 00050 plusmn 000018 00074 plusmn 000025 lt00001Ovaries 0015 plusmn 000064 0014 plusmn 000083 014Pancreas 0014 plusmn 000085 0018 plusmn 00015 000018Red marrow 0010 plusmn 000037 0012 plusmn 000032 lt00001Osteogenic cells 0017 plusmn 000094 0016 plusmn 00019 043Skin 0010 plusmn 000054 00080 plusmn 000080 000019Small intestine 0014 plusmn 000047 0015 plusmn 000049 00034Spleen 0014 plusmn 00011 0018 plusmn 00022 000074Stomach wall 0013 plusmn 000065 0014 plusmn 000041 00057Testes 0013 plusmn 000062 0010 plusmn 00010 00012Thymus 0011 plusmn 000068 0010 plusmn 00013 0014Thyroid 0011 plusmn 000072 00094 plusmn 00014 0017Upper large intestine wall 0014 plusmn 000046 0015 plusmn 000045 00036Urinary bladder wall 020 plusmn 0087 0081 plusmn 0032 00037Uterus 0018 plusmn 00017 0017 plusmn 00012 031Total body 0013 plusmn 000041 0012 plusmn 000012 000073Effective dose 0024 plusmn 00041 0022 plusmn 00042 058lowastUnpaired 2-tailed Studentrsquos 119905-test

4 Discussion

VAP-1 targeted ligands are promising tools for PET imagingof inflammation In this study we compared theVAP-1 target-ing tracers 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 in thedetection of experimental inflammation in rats and mice andalso estimated the radiation burden to humans We foundthat the uptake of both tracers was higher in skinmuscleinflammation than in healthy muscle and in atheroscleroticrather than in nonatherosclerotic arterial walls Both tracersresulted in a low radiation exposure but the lower-cost andmore straightforward radiolabeling procedures support the

potential use of 68Ga-DOTA-Siglec-9 for PET imaging ofpatients with inflammation

The tested tracers have a similar amino acid sequence buta differently conjugated peptide structure (68Ga-DOTA ver-sus 18F-FDR) We hypothesized that the 18F-labeled tracerwould provide improved visualization of inflammatory focibecause it has a lower positron range (027mm) than 68Ga(105mm) For PET imaging 18F (11990512 = 110min 120573+max =640 keV 120573+ = 97) is an ideal radionuclide providing a highspatial resolution in the resulting images 68Ga (11990512 = 68min 120573+max = 1899 keV 120573

+ = 89) is a positron-emitting


Table 5 Ex vivo biodistribution ( IDg) of 18F-FDR-Siglec-9 at 25min after injection in atherosclerotic and control mice

Organ LDLRminusminusApoB100100(119899 = 19)

C57BL6N(119899 = 13)

119875 valuelowast

Aorta 093 plusmn 038 052 plusmn 023 00014Adipose tissue BAT 057 plusmn 14 045 plusmn 013 016Adipose tissue WAT 072 plusmn 066 063 plusmn 037 067Blood 32 plusmn 082 21 plusmn 059 000025Brain 015 plusmn 0060 011 plusmn 0048 0026Heart 062 plusmn 028 034 plusmn 0082 00019Kidney 44 plusmn 26 43 plusmn 25 086Liver 30 plusmn 097 35 plusmn 23 037Lungs 24 plusmn 11 15 plusmn 045 0011Muscle 062 plusmn 020 043 plusmn 013 00056Pancreas 082 plusmn 028 057 plusmn 018 0011Plasma 57 plusmn 14 38 plusmn 062 000015Small intestine 16 plusmn 049 079 plusmn 029 lt00001Spleen 11 plusmn 028 062 plusmn 032 0054Thymus 069 plusmn 019 043 plusmn 0089 lt00001Urine 470 plusmn 370 610 plusmn 340 027 IDg = percentage of injected radioactivity dose per gram of tissue BAT = brown adipose tissue WAT = white adipose tissue lowastUnpaired 2-tailed Studentrsquost-test

AutofluorescenceMerge Anti-VAP-1B

LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)

Merge Anti-VAP-1 Autofluorescence

W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)

Figure 3 VAP-1 immunofluorescence of (a) atherosclerotic LDLRminusminusApoB100100 and (b) C57BL6N controlmice aortas AA ascending aortaA aortic arch LC left common carotid artery LS left subclavian artery P plaque Wwall and Ad adipocyte


BloodAorta Heart

P = 00019

P = 000025

P = 00014

C57BLN6LDL２minusminus Apo100100

0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)

Plaque Wall Adventitia

P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)

Figure 4 (a) The 18F-FDR-Siglec-9 PETCT detects atherosclerotic plaques in the aortic root with a target-to-background ratio(SUVmaxaortic archSUVmeanblood) of 16 The blood radioactivity concentration was determined from heart left ventricle using contrast-enhanced CT as anatomical reference Arrow shows calcified atherosclerotic plaques in the aortic arch (a) (b) Ex vivo biodistribution of18F-FDR-Siglec-9 in LDLRminusminusApoB100100 (119899 = 19) and C57BLN6 (119899 = 13) mice (c) Quantification of 18F-FDR-Siglec-9 binding on theautoradiography of atherosclerotic mice aortas (119899 = 12 P values one-way ANOVAwith Tukeyrsquos correction) (d) Representative hematoxylin-eosin staining of a longitudinally sectioned LDLRminusminusApoB100100 mouse aorta and (e) a superimposed autoradiograph (red lines representthe borders of the hematoxylin-eosin image) R1 and R2 are regions of interest in the plaque (excluding the media) R3 is in normalvessel wall (no lesion formation) and R4 is in adventitia (mainly adipose tissue around the aorta) (f) Hematoxylin-eosin staining of alongitudinally sectioned healthy C57BL6N control mouse aorta (g) Superimposed autoradiograph and hematoxylin-eosin staining (theblack line represents the borders of the hematoxylin-eosin image) A arch AA ascending aorta B brachiocephalic artery LC left commoncarotid artery and LS left subclavian artery PSLmm2 = photostimulated luminescencemm2 normalized for injected radioactivity dose


radiometal that is particularly suitable for the labeling ofchelate-conjugated peptides While production of 18F re-quires a cyclotron 68Ga is produced with an easily accessiblelow-cost 68Ge68Ga-generator [17]

Although the inflammation detection characteristics of68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 were similar theuptake of 18F-FDR-Siglec-9 was higher in several nontar-get tissues including the control area We do not have aclear explanation for the distinctive distribution patternsparticularly in the liver pancreas heart and kidneys butsuspect that they were at least partly due to the sugar moietySimilar results have been observed with 68Ga-DOTANOCand 18F-FDR-NOC [18] 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 showed comparable in vivo imaging of inflamma-tion in the rat model The difference in the control areabetween the two tracers might at least partly be explainedby the higher blood pool radioactivity of 18F-FDR-Siglec-9 Although both 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 clearly delineated inflamed area by in vivo PET the 18F-FDG uptake was higher (SUVmean 20 plusmn 052 at 90min afterinjection) as reported in our previous rat studies withturpentine-induced inflammation [16]

As we earlier reported the LDLRminusminusApoB100100 miceexpressed VAP-1 on endothelial cells lining the inflamedatherosclerotic lesions while normal vessel walls in the aortasof C57BL6N mice were VAP-1-negative [4] In atheroscle-rotic mice the aortic uptake of 18F-FDR-Siglec-9 was com-parable to the previously reported uptake of 68Ga-DOTA-Siglec-9 [4] With both tracers the atherosclerotic lesions inmice were best detectable by in vivo PETCT imaging at10ndash20min after injection Autoradiography revealed that theplaque-to-healthy vessel wall ratios were slightly higher with68Ga-DOTA-Siglec-9 than with 18F-FDR-Siglec-9 althoughboth were close to the previously reported ratio for 18F-FDG(23 plusmn 05) in a LDLRminusminusApoB100100 model [13]

In general in vivo PET imaging of such a small targetas atherosclerotic lesion in mice aorta is very challengingWhen size of the imaged structures is smaller than the spatialresolution of the scanner spillover from adjacent tissuesand partial volume effect may invalidate the quantificationof PET data in addition to cardiac and respiratory move-ment artifacts Although small-animal PETCT image ofatherosclerotic mouse showed hot spot in the lesion-richaortic arch (Figure 4(a)) the ex vivo biodistribution showedthat uptake in the whole thoracic aorta was much lower thanthe blood level (Figure 4(b)) Therefore it is possible that thePETCT imaging of atherosclerotic lesions is interfered withblood pool radioactivity On the contrary in the rat modelthe size and location of focal skinmuscle inflammation aswell as the blood radioactivity concentrationweremuchmorefavorable for reliable PET imaging of inflamed area The PETscanning protocols and quantification methods used in thisstudy were based on our previous research to allow directcomparison of new and already existing results

Extrapolated from rat PET data the human radia-tion dose estimates for both 68Ga-DOTA-Siglec-9 (0024 plusmn00041mSvMBq) and 18F-FDR-Siglec-9 (0022 plusmn 00042mSvMBq) were similar to those for other 68Ga-labeled tracers

(eg 68Ga-DOTANOC 0025mSvMBq) or 18F-FDG (0019mSvMBq) [19 20]

5 Conclusion

VAP-1 targeted 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 peptides are potential tracers for the PET imaging ofinflammationThe human radiation dose estimates indicate alow radiation exposure with either of the investigated tracersThe present study further strengthens the concept of aVAP-1-based imaging strategy for the in vivo detection ofinflammation by PET

Conflicts of Interest

Sirpa Jalkanen owns stocks in FaronPharmaceuticals LtdTheremaining authors have no conflicts of interest to disclose

Acknowledgments

The authors thank Erica Nyman Marja-Riitta Kajaala LiisaLempiainen Aake Honkaniemi Timo Kattelus and SariMaki for technical assistance This research was conductedwithin the Finnish Centre of Excellence in Cardiovascu-lar and Metabolic Diseases supported by the Academy ofFinland University of Turku Turku University Hospitaland Abo Akademi University The research leading to theseresults was further supported by funding from the Academyof Finland (no 258814) the State Research Funding (no13856) the Finnish Foundation for Cardiovascular Researchand the Sigrid Juselius Foundation

References

[1] C Wu F Li G Niu and X Chen ldquoPET imaging of inflamma-tion biomarkersrdquoTheranostics vol 3 no 7 pp 448ndash466 2013

[2] M Salmi and S Jalkanen ldquoEctoenzymes in leukocytemigrationand their therapeutic potentialrdquo Seminars in Immunopathologyvol 36 no 2 pp 163ndash176 2014

[3] T Anger F K Pohle L Kandler et al ldquoVAP-1 Eotaxin3 andMIG as potential atherosclerotic triggers of severe calcified andstenotic human aortic valves Effects of statinsrdquo Experimentaland Molecular Pathology vol 83 no 3 pp 435ndash442 2007

[4] J M U Silvola H Virtanen R Siitonen et al ldquoLeukocytetrafficking-associated vascular adhesion protein 1 is expressedand functionally active in atherosclerotic plaquesrdquo ScientificReports vol 6 Article ID 35089 2016

[5] A Bulgarelli A A Martins Dias B Caramelli and R CMaranhao ldquoTreatment with methotrexate inhibits atherogen-esis in cholesterol-fed rabbitsrdquo Journal of Cardiovascular Phar-macology vol 59 no 4 pp 308ndash314 2012

[6] K Aalto M Maksimow M Juonala et al ldquoSoluble vascularadhesion protein-1 correlates with cardiovascular risk fac-tors and early atherosclerotic manifestationsrdquo ArteriosclerosisThrombosis and Vascular Biology vol 32 no 2 pp 523ndash5322012

[7] H-Y Li M-S Lin J-N Wei et al ldquoChange of serum vas-cular adhesion protein-1 after glucose loading correlates tocarotid intima-medial thickness in non-diabetic subjectsrdquoClin-ica Chimica Acta vol 403 no 1-2 pp 97ndash101 2009


[8] K Aalto A Autio E A Kiss et al ldquoSiglec-9 is a novel leukocyteligand for vascular adhesion protein-1 and can be used in PETimaging of inflammation and cancerrdquo Blood vol 118 no 13 pp3725ndash3733 2011

[9] X-G Li A Autio H Ahtinen et al ldquoTranslating the concept ofpeptide labeling with 5-deoxy-5-[ 18F]fluororibose into preclin-ical practice 18F-labeling of Siglec-9 peptide for PET imaging ofinflammationrdquo Chemical Communications vol 49 no 35 pp3682ndash3684 2013

[10] H Ahtinen J Kulkova L Lindholm et al ldquo 68Ga-DOTA-Sig-lec-9 PETCT imaging of peri-implant tissue responses andstaphylococcal infectionsrdquo EJNMMI Research vol 4 no 1article no 45 pp 1ndash11 2014

[11] H Virtanen A Autio R Siitonen et al ldquo 68Ga-DOTA-Siglec-9- a new imaging tool to detect synovitisrdquo Arthritis Research ampTherapy vol 17 no 1 article no 308 2015

[12] S Yamada K Kubota R Kubota T Ido and N TamahashildquoHigh accumulation of fluorine-18-fluorodeoxyglucose inturpentine-induced inflammatory tissuerdquo Journal of NuclearMedicine vol 36 no 7 pp 1301ndash1306 1995

[13] J M U Silvola A Saraste I Laitinen et al ldquoEffects of age dietand type 2 diabetes on the development and FDG uptake ofatherosclerotic plaquesrdquo JACC Cardiovascular Imaging vol 4no 12 pp 1294ndash1301 2011

[14] K Mikkola C-B Yim V Fagerholm et al ldquo 64Cu- and 68Ga-labelled [Nle14Lys40(Ahx-NODAGA)NH2]-exendin-4 for pan-creatic beta cell imaging in ratsrdquoMolecular Imaging and Biologyvol 16 no 2 pp 255ndash263 2014

[15] MMerinenH IrjalaM Salmi I Jaakkola AHanninen and SJalkanen ldquoVascular adhesion protein-1 is involved in both acuteand chronic inflammation in the mouserdquoTheAmerican Journalof Pathology vol 166 no 3 pp 793ndash800 2005

[16] A Autio T Ujula P Luoto S Salomaki S Jalkanen and ARoivainen ldquoPET imaging of inflammation and adenocarcinomaxenografts using vascular adhesion protein 1 targeting peptide68Ga-DOTAVAP-P1 Comparison with 18F-FDGrdquo EuropeanJournal of Nuclear Medicine and Molecular Imaging vol 37 no10 pp 1918ndash1925 2010

[17] A Sanchez-Crespo ldquoComparison of Gallium-68 and Fluorine-18 imaging characteristics in positron emission tomographyrdquoApplied Radiation and Isotopes vol 76 pp 55ndash62 2013

[18] P Rinne S Hellberg M Kiugel et al ldquoComparison of somato-statin receptor 2-targeting pet tracers in the detection of mouseatherosclerotic plaquesrdquoMolecular Imaging and Biology vol 18no 1 pp 99ndash108 2016

[19] C Pettinato A SarnelliMDiDonna et al ldquo 68Ga-DOTANOCBiodistribution and dosimetry in patients affected by neuroen-docrine tumorsrdquo European Journal of Nuclear Medicine andMolecular Imaging vol 35 no 1 pp 72ndash79 2008

[20] International Commission on Radiological Protection Pub-lication 80 ldquoRecalculated dose data for 19 frequently usedradiopharmaceuticals from ICRP publication 53rdquo Annals of theICRP ICRP vol 28 pp 47ndash83 1998

Submit your manuscripts athttpswwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


MEDIATORSINFLAMMATION

of


Behavioural Neurology

EndocrinologyInternational Journal of



Disease Markers


BioMed Research International

OncologyJournal of



Oxidative Medicine and Cellular Longevity


PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of



Computational and Mathematical Methods in Medicine

OphthalmologyJournal of


Diabetes ResearchJournal of



Research and TreatmentAIDS


Gastroenterology Research and Practice


Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom


Table 1 Characteristics of study animals

Sprague-Dawley skininflammation rats

LDLRminusminusApoB100100atherosclerotic mice

C57BL6N controlmice

Age (months) 22 plusmn 0051 56 plusmn 096 21 plusmn 039High fat diet (months) ND 36 plusmn 10 NDFemalemale (no) 016 154 67Weight (g) 350 plusmn 22 27 plusmn 40 24 plusmn 22In vivo PET (no) 13 2 2Ex vivo gamma counting (no) 16 19 13Ex vivo autoradiography (no) ND 12 10LDLRminusminusApoB100100 = low-density lipoprotein receptor-deficient mouse expressing only apolipoprotein B100 ND = not done no = number of investigatedanimals

if the inflammation continues which suggest VAP-1 as apromising target for both anti-inflammatory therapy andmolecular imaging of inflammation [2] The role of VAP-1in atherosclerotic inflammation is unclear VAP-1 expressionis upregulated in atherosclerotic plaques in human carotidarteries [3 4] and in the aorta of hypercholesterolemic rabbits[5] VAP-1 is also expressed in soluble form (sVAP-1) whichassociates with atherosclerosis [6 7]

We previously showed that sialic acid-binding immuno-globulin-like lectin 9 (Siglec-9) is a VAP-1 ligand and theradiolabeled peptide (CARLSLSWRGLTLCPSK) containingresidues 283ndash297 from Siglec-9 can be used for PET imagingof inflammation [4 8ndash11]

In this study we examined the detection of skinmuscleinflammation in rats comparing the utility of the Siglec-9motif peptides 68Ga-labeled 14710-tetraazacyclododecane-NN1015840N10158401015840N101584010158401015840-tetraacetic acid-conjugated 68Ga-DOTA-Sig-lec-9 and 18F-labeled fluorodeoxyribose-conjugated 18F-FDR-Siglec-9 [9] We also examined 18F-FDR-Siglec-9 up-take in inflamed atherosclerotic plaques of mice and com-pared it with previous 68Ga-DOTA-Siglec-9 results [4]Finally we used the rat PET data to estimate the human radi-ation doses for 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9

2 Materials and Methods

21 Radiochemistry 68Ga-DOTA-Siglec-9 and 18F-FDR-Sig-lec-9 were produced as previously described [8 9]

22 Animal Models Twenty-four hours before the PETstudies Sprague-Dawley rats (weight 350 plusmn 22 g 119899 = 16)were subcutaneously injected with turpentine oil (Sigma-Aldrich) to induce focal acute sterile inflammation [12]Before the injection rats were shaved on the both forelegsInflamed area on the left foreleg contained both skin andmuscle The intact contralateral side (right foreleg) was usedas a control

Six-month-old atherosclerotic low-density lipoproteinreceptor-deficient mice (weight 27 plusmn 41 g 119899 = 19) express-ing only apolipoprotein B100 (LDLRminusminusApoB100100 strain003000 JacksonLaboratory BarHarborMEUSA)were fedfor 4 months with a Western-type diet [13] Two-month-oldC57BL6Nmice (weight 24 plusmn 22 g 119899 = 13) fedwith a regularchow served as controls

All animal experiments (Table 1) were approved by thenational Animal Experiment Board in Finland and carriedout in compliance with the EU directive

23 Rat Studies Rats were divided into two groups withGroup 1 being intravenously (iv) given 68Ga-DOTA-Siglec-9(16 plusmn 29MBq 119899 = 8) andGroup 2 18F-FDR-Siglec-9 (18 plusmn 51MBq 119899 = 8) A 60min dynamic PET acquisition wasperformed on a High Resolution Research Tomograph(HRRT Siemens Medical Solutions Knoxville TN USA)The PET data were reconstructed into 5 times 60 s and 11 times 300 sframes using an ordered-subsets expectation maximization3D algorithm (OSEM3D) Quantitative PET image analysiswas performed by defining regions of interest (ROIs) withinthe inflamed area (on the left foreleg) control area (on theright foreleg) kidneys lungs heart liver and urinary bladderusing Carimas 28 software (Turku PET Centre) Resultswere expressed as standardized uptake values (SUV) andtime-activity curves SUV was calculated as a ratio of tissueradioactivity concentration (BqmL) and given radioactivitydose (Bq) divided by animalrsquos body weight

After PET imaging rats were sacrificed and varioustissues were excised and weighed and their radioactivitylevels weremeasuredwith a gamma counter (1480Wizard 310158401015840PerkinElmer Turku Finland) The ex vivo biodistributionresults were expressed as a percentage of the injected radioac-tivity dose per gram of tissue ( IDg) and target-to-background ratio

The inflamed area and control area tissue samples werefrozen cut into sections and stained with hematoxylin-eosin(HampE) for morphological evaluation

Absorbed doses of 68Ga-DOTA-Siglec-9 and 18F-FDR-Siglec-9 were calculated with the OLINDAEXM version 10software (organ level internal dose assessment and exponen-tial modeling Vanderbilt University Nashville TN USA)which applies the MIRD schema (developed by the Med-ical Internal Radiation Dose committee of the Society ofNuclear Medicine) for radiation dose calculations in internalexposure The software includes radionuclide informationand selection of human body phantoms The residence timesderived from the rat datawere integrated as the area under thetime-activity curve The residence times were converted intocorresponding human values by multiplication with a factor










3 Results

















High


5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

0

3

6

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)


LiverLungs

(a)

High

Low

0

3

6

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)



LiverLungs

(b)

18-FDR-Siglec-9

68a-DOTA-Siglec-9

0

05

10

15

20

25

Infla

med

area

-to-b

lood

ratio

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

(c)









4 Discussion








C57BL6N(119899 = 13)

119875 valuelowast



LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)


W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)



BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

























3 Results

















High


5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

0

3

6

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)


LiverLungs

(a)

High

Low

0

3

6

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)



LiverLungs

(b)

18-FDR-Siglec-9

68a-DOTA-Siglec-9

0

05

10

15

20

25

Infla

med

area

-to-b

lood

ratio

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

(c)









4 Discussion








C57BL6N(119899 = 13)

119875 valuelowast



LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)


W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)



BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



























High


5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

0

3

6

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)


LiverLungs

(a)

High

Low

0

3

6

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)



LiverLungs

(b)

18-FDR-Siglec-9

68a-DOTA-Siglec-9

0

05

10

15

20

25

Infla

med

area

-to-b

lood

ratio

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

(c)









4 Discussion








C57BL6N(119899 = 13)

119875 valuelowast



LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)


W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)



BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

















High


5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

0

3

6

In v

ivo

68 G

a-D

OTA

-Sig

lec-

9 (S

UV

)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)


LiverLungs

(a)

High

Low

0

3

6

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

0102030405060708090

100110

In v

ivo

18F-

FDR-

Sigl

ec-9

(SU

V)



LiverLungs

(b)

18-FDR-Siglec-9

68a-DOTA-Siglec-9

0

05

10

15

20

25

Infla

med

area

-to-b

lood

ratio

5 10 15 20 25 30 35 40 45 50 55 600Time (min)

(c)









4 Discussion








C57BL6N(119899 = 13)

119875 valuelowast



LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)


W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)



BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of























4 Discussion








C57BL6N(119899 = 13)

119875 valuelowast



LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)


W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)



BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



















C57BL6N(119899 = 13)

119875 valuelowast



LC

ALS

W

P

anti-VAP-1

W

P

W

PAA

500 m

100 m 100 m 100 m

(a)


W

anti-VAP-1Ad

W WAd

W W

WAd

500 m500 m500 m

(b)



BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

















BloodAorta Heart

P = 00019

P = 000025

P = 00014


0

1

2

3

4

Ex v

ivo

18

-FD

R-Si

glec

-9 (

IDg

)


P lt 00001

P lt 00001

P = 0028

020406080

100120140160180200

18

-FD

R-Si

glec

-9 (P

SLm

Ｇ2)

LSLC

A AA

B

200 m

R2

R1

R3

R4

High

Low

AAADW

A

AD

High

Low

High

Low

CT PET PETCT

AA

LV

AA

LV LV

AA

(a)

(b) (c)

(d) (e)

(f) (g)









5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of























5 Conclusion




Acknowledgments


References



























of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of





















of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of
















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