Molecular Imaging and Biology

, Volume 16, Issue 6, pp 813–820 | Cite as

Preclinical Imaging Evaluation of Novel TSPO-PET Ligand 2-(5,7-Diethyl-2-(4-(2-[18F]fluoroethoxy)phenyl)pyrazolo[1,5-a]pyrimidin-3-yl)-N,N-diethylacetamide ([18F]VUIIS1008) in Glioma

  • Dewei Tang
  • Michael L. Nickels
  • M. Noor Tantawy
  • Jason R. Buck
  • H. Charles ManningEmail author
Research Article



Translocator protein (TSPO) concentrations are elevated in glioma, suggesting a role for TSPO positron emission tomography (PET) imaging in this setting. In preclinical PET studies, we evaluated a novel, high-affinity TSPO PET ligand, [18F]VUIIS1008, in healthy mice and glioma-bearing rats.


Dynamic PET data were acquired simultaneously with [18F]VUIIS1008 injection, with binding reversibility and specificity evaluated in vivo by non-radioactive ligand displacement or blocking. Compartmental analysis of PET data was performed using metabolite-corrected arterial input functions. Imaging was validated with histology and immunohistochemistry.


[18F]VUIIS1008 exhibited rapid uptake in TSPO-rich organs. PET ligand uptake was displaceable with non-radioactive VUIIS1008 or PBR06 in mice. Tumor accumulation of [18F]VUIIS1008 was blocked by pretreatment with VUIIS1008 in rats. [18F]VUIIS1008 exhibited improved tumor-to-background ratio and higher binding potential in tumors compared to a structurally similar pyrazolopyrimidine TSPO ligand, [18F]DPA-714.


The PET ligand [18F]VUIIS1008 exhibits promising characteristics as a tracer for imaging glioma. Further translational studies appear warranted.

Key words

PET DPA-714 VUIIS1008 TSPO Glioma Cancer imaging 



The authors thank George H. Wilson and Daniel Colvin for the assistance with microPET and MR imaging studies, respectively, Allie Fu for preclinical model support, and Matthew R. Hight and Michael L. Schulte for editing the manuscript and helpful discussions. The authors acknowledge funding from the National Institutes of Health (K25 CA127349, P50 CA128323, S10 RR17858, U24 CA126588, 1R01 CA163806) and the Kleberg Foundation.

Conflict of Interest

The authors do not have any conflicts of interest.

Supplementary material

11307_2014_743_MOESM1_ESM.pdf (92 kb)
ESM 1 (PDF 91 kb)


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Copyright information

© World Molecular Imaging Society 2014

Authors and Affiliations

  • Dewei Tang
    • 1
    • 2
  • Michael L. Nickels
    • 1
    • 2
  • M. Noor Tantawy
    • 1
    • 2
  • Jason R. Buck
    • 1
    • 2
  • H. Charles Manning
    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    Email author
  1. 1.Vanderbilt University Institute of Imaging Science (VUIIS)Vanderbilt University Medical CenterNashvilleUSA
  2. 2.Department of Radiology and Radiological SciencesVanderbilt University Medical CenterNashvilleUSA
  3. 3.Program in Chemical and Physical BiologyVanderbilt University Medical CenterNashvilleUSA
  4. 4.Vanderbilt-Ingram Cancer CenterVanderbilt University Medical CenterNashvilleUSA
  5. 5.Department of Biomedical EngineeringVanderbilt UniversityNashvilleUSA
  6. 6.Department of NeurosurgeryVanderbilt University Medical CenterNashvilleUSA
  7. 7.Vanderbilt Institute of Chemical BiologyVanderbilt University Medical CenterNashvilleUSA

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