Department of Biomedical Imaging and Image-guided Therapy (Division of Nuclear Medicine)
Position: Research Associate (Postdoc)
ORCID: 0000-0003-2065-6093
T +43 1 40400 58720
chrysoula.vraka@meduniwien.ac.at
Keywords
Drug Evaluation, Preclinical; Molecular Imaging; Neurosciences; Positron-Emission Tomography; Radioactive Tracers
Research group(s)
- Experimental Nuclear Medicine
Head: Cécile Philippe
Research Area: The research group "Experimental Nuclear Medicine" deals with the development and evaluation of radiotracers in various diseases. In addition, the group focuses on organ axes and pharmacokinetics.
Members: - Translational Chronic Mental Stress (Vraka Group)
Head: Chrysoula Vraka
Research Area: Chronic mental stress is a key but underrecognized risk factor for metabolic and inflammatory disorders, contributing to diseases like CVD, depression, neurodegeneration, and cancer. Stress alters metabolism via cortisol, promoting insulin resistance and fat storage. PET biomarkers enable insight into stress-inflammation links. We aim for a bidirectional mouse-human translational pipeline to uncover mechanisms and support preventive strategies.
Members:
Research interests
My main research focus was to understand the pharmacokinetic properties of radiotracers to accelerate and improve drug development in neuroscience, and cancer from bench-to-bed with focus on the Blood Brain Barrier (BBB).
With this background, my current work encompasses whole body tracer imaging with special focus on organ axes between lymphoid organs and disease location under chronic mental stress. Hence, we have established different mouse stress models to investigate how chronic stress contributes to poor immune surveillance, patient outcome, prognosis and the effect on immunotherapy response. Within the next three Years, I will investigate in an international consortium (EPILUCAFS) epigenetic drivers of cancer-associated fibroblasts in chronic stress and immunosuppression in lung cancer. Currently, I am performing image-based metabolic phenotyping of KRAS driven lung cancer mouse models using positron emission tomography (PET). To overcome poor spatial resolution of PET, we have established a radioactive cell sorting technique (radioFlow) with the aim of understanding immune cell metabolism and metabolite competition within the tumour microenvironment and lymphoid organs in cancer. Using total PET body information, combined with molecular biology techniques, a further objective is to investigate new biomarkers.
Techniques, methods & infrastructure
- Radiolabeling (PET, SPECT, Therapeutics)
- Drug development: in vitro techniques as lipophilicity, permeability, plasma protein binding, drug distribution and metabolism, cell culture (co-culture models and real-time kinetic assays), binding studies, autoradiography and ex vivo & in vitro metabolism and biodistribution studies.
- In vivo radio-metabolite analysis for kinetic modeling (human and animal studies)
- Preclinical Imaging µPET/µCT
- Metabolic Imaging
- Cancer Imaging
- Neuro Imaging
- Imaging Organ-Axis/Organ-Crosstalk
- Stress Mouse Models
- RadioFlow
- Molecular Biology Techniques (wetlab)
Grants
- Chronic stress and immunosuppression in lung cancer: focus on epigenetic drivers in cancer-associated fibroblasts (EPILUCAFS) (2024)
Source of Funding: EU, TRANSCAN-3
Principal Investigator
Selected publications
- Spielvogel, C.P. et al. (2025) ‘Enhancing Blood–Brain Barrier Penetration Prediction by Machine Learning-Based Integration of Novel and Existing, In Silico and Experimental Molecular Parameters from a Standardized Database’, Journal of Chemical Information and Modeling, 65(6), pp. 2773–2784. Available at: https://doi.org/10.1021/acs.jcim.4c02212.
- Yu, J. et al. (2024) ‘Systemic Metabolic and Volumetric Assessment via Whole-Body [18F]FDG-PET/CT: Pancreas Size Predicts Cachexia in Head and Neck Squamous Cell Carcinoma’, Cancers, 16(19), p. 3352. Available at: https://doi.org/10.3390/cancers16193352.
- Vraka, C. et al. (2025) ‘RadioFlow Cytometry Reveals That [18F]FDG Uptake in K-RAS Lung Cancer Is Driven by Immune Cells: An Analysis on a Single-Cell Level’, Journal of Nuclear Medicine, 66(2), pp. 215–222. Available at: https://doi.org/10.2967/jnumed.124.268799.
- Vraka, C. et al. (2022) ‘Simultaneous radiomethylation of [11C]harmine and [11C]DASB and kinetic modeling approach for serotonergic brain imaging in the same individual’, Scientific Reports, 12(1). Available at: http://dx.doi.org/10.1038/s41598-022-06906-0.
- Rischka, L. and Vraka, C. et al. (2021) ‘First-in-Humans Brain PET Imaging of the GluN2B-Containing N-methyl-d-aspartate Receptor with (R)-11C-Me-NB1’, Journal of Nuclear Medicine, 63(6), pp. 936–941. Available at: http://dx.doi.org/10.2967/jnumed.121.262427.