Développement d'une micro-angiographie par fluorescence-X pour de diagnostic des tumeurs angiogéniques – MIAG-X

The imaging techniques currently used in clinics are decried because of the harmfulness of the contrast agents (toxic or radioactive) they use and their performances sometimes insufficient. We propose to evaluate the analytical performances of an imaging based on X-ray fluorescence of blood vessels on reproducible models of tumors analyzed in vivo. The Bordeaux laboratories involved in the project are currently the leader in the controlled development of gliomas in rats and in the determination of molecular parameters to the tumor grades. The Taiwan laboratories were the first to propose an imaging technique based on X-ray fluorescence that uses gold nanoparticles non-toxic and injectable, suggesting that micro-angiography of brain tumors is feasible. The key step of glioma growth toward malignant grades is the angiogenic switch, which allows the tumor to grow and to become more aggressive. Actually, there is no routine in vivo imaging method able to diagnose low grade glioma (< grade III = 2-4 mm3 in size) and no efficient treatment exists to avoid death of patients diagnosed with high grade glioma. The development of new in vivo imaging methods for angiography at the micron scale resolution is thus a major challenge in the field. The research project focuses on the development of X-Ray fluorescence based micro-angiography for diagnosing glioma using non-toxic contrast agents. The Bordeaux partners include chemists involved in the development of molecular imaging methods (?-PET, FTIR...) and biologists developing glioma models using: 1- cultures of brain vascular endothelial cells (HCMEC) involved in key steps of tumor blood vessels formation, and 2- tumor mouse (intracranial) models developing the different grades of glioma. The Taiwan partners include physicists developing multimodal in vivo imaging methods (?XRF, ?-angiography, ?-PET’) and neurologists developing contrast agents for vascular imaging.