Oxygenation; Protoporphyrin IX; Biological tissues; In vivo; Lesion demarcation; Time-resolved luminescence imaging; Molecular Probes; Metabolism; Martorell's ulcer
Huntosova Veronika, Gerelli Emmanuel, Zellweger Matthieu, Wagnières Georges (2016), Effect of PpIX photoproducts formation on pO2 measurement by time-resolved delayed fluorescence spectroscopy of PpIX in solution and in vivo., in Journal of photochemistry and photobiology. B, Biology
, 164, 49-56.
Wang Yabo, Wang Xingyu, Le Bitoux Marie-Aude, Wagnieres Georges, Vandenbergh Hubert, Gonzalez Michel, Ris Hans-Beat, Perentes Jean Y, Krueger Thorsten (2015), Fluence plays a critical role on the subsequent distribution of chemotherapy and tumor growth delay in murine mesothelioma xenografts pre-treated by photodynamic therapy., in Lasers in surgery and medicine
, 47(4), 323-30.
Pitzschke Andreas, Lovisa Blaise, Seydoux Olivier, Haenggi Matthias, Oertel Markus F, Zellweger Matthieu, Tardy Yanik, Wagnières Georges (2015), Optical properties of rabbit brain in the red and near-infrared: changes observed under in vivo, postmortem, frozen, and formalin-fixated conditions., in Journal of biomedical optics
, 20(2), 25006-25006.
Huntosova Veronika, Stroffekova Katarina, Wagnieres Georges, Novotova Marta, Nichtova Zuzana, Miskovsky Pavol (2014), Endosomes: guardians against [Ru(Phen)(3)](2+) photo-action in endothelial cells during in vivo pO(2) detection?, in METALLOMICS
, 6(12), 2279-2289.
Huntosova Veronika, Gay Sandrine, Nowak-Sliwinska Patrycja, Rajendran Senthil Kumar, Zellweger Matthieu, van den Bergh Hubert, Wagnieres Georges (2014), In vivo measurement of tissue oxygenation by time-resolved luminescence spectroscopy: advantageous properties of dichlorotris(1, 10-phenanthroline)-ruthenium(II) hydrate, in JOURNAL OF BIOMEDICAL OPTICS
, 19(7), 077004-1-077004-12.
Perentes Jean Yannis, Wang Yabo, Wang Xingyu, Abdelnour Etienne, Gonzalez Michel, Decosterd Laurent, Wagnieres Georges, van den Bergh Hubert, Peters Solange, Ris Hans-Beat, Krueger Thorsten (2014), Low-Dose Vascular Photodynamic Therapy Decreases Tumor Interstitial Fluid Pressure, which Promotes Liposomal Doxorubicin Distribution in a Murine Sarcoma Metastasis Model., in Translational oncology
, 7(3), 393-399.
Varchola Jaroslav, Huntosova Veronika, Jancura Daniel, Wagnieres Georges, Miskovsky Pavol, Bano Gregor (2014), Temperature and oxygen-concentration dependence of singlet oxygen production by RuPhen as induced by quasi-continuous excitation, in PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
, 13(12), 1781-1787.
Piffaretti Filippo, Zellweger Matthieu, Kasraee Behrooz, Barge Jérôme, Salomon Denis, van den Bergh Hubert, Wagnières Georges (2013), Correlation between protoporphyrin IX fluorescence intensity, photobleaching, pain and clinical outcome of actinic keratosis treated by photodynamic therapy., in Dermatology (Basel, Switzerland)
, 227(3), 214-25.
Huntosova Veronika, Gerelli Emmanuel, Horvath Denis, Wagnieres Georges, Measurement of pO2 by luminescence lifetime spectroscopy: A comparative study of the phototoxicity and sensitivity of [Ru(Phen)3 ](2+) and PdTCPP in vivo., in Journal of biophotonics
The general objective of this project is to develop new techniques to produce images of the oxygenation and metabolic activity of biological tissues by time-resolved luminescence spectroscopy of endogenous and exogenous molecular probes. This approach will provide useful fundamental information regarding the metabolic mechanisms that are in relation with the oxygen delivery and consumption, in particular during photodynamic therapy (PDT). In addition, this project will provide useful fundamental information regarding the metabolic activities involved in the endogenous production of a heme precursor, protoporphyrin IX (PPIX), an approved luminescent photosensitizer. Medical applications of the approach proposed here will enable to delineate, monitor and individualize therapies of conditions affecting the skin, such as actinic keratosis (AK) and Martorell's ulcer.More precisely, our first specific objective is to develop formulations and derivations of molecular probes that are sensitive to the oxygen partial pressure (pO2) in such a way that no photodamages are induced in the tissues during the measurement. These damages are observed with virtually all pO2 probes used in approaches based on the measurement of the oxygen quenching of their luminescence. Such “minimally invasive” pO2 probes will find numerous in vitro, preclinical and possibly clinical applications to achieve the general objective mentioned above.A second specific objective of this project is the individualization of the light dose during PDT of AK using the methylaminolevulinate (MAL)-induced PPIX delayed fluorescence. The new approach we propose in this project consists to exploit the quenching of the delayed fluorescence of an approved photosensitizer, the MAL-induced PPIX, to determine the oxygen concentration in the tissues and to adapt the therapeutic light dose accordingly. One major advantage of the approach proposed here, as compared to the “standard” approaches based on the use of the oxygen quenching of the phosphorescence of metallo-porphyrins, is related to its potential clinical use since we plan to use an approved photosensitizer for this purpose. This PPIX will also be used to image the metabolic activity and the tissue oxygenation in, and around, Martorell's ulcer to improve their demarcation. The main goal of this approach is to provide a guidance to improve the surgical resection of these lesions.Two time-resolved imaging systems will be developed to perform luminescence lifetime measurements on microscopic (in vitro or preclinical studies) or macroscopic (preclinical or clinical studies) samples. Different magnifications will be achieved by coupling these systems to dedicated optics (fluorescence microscope or "macro" objective). The imaging systems will be dedicated to applications where a spatial resolution of the pO2 measurement is of importance, whereas a point measurement system, already available in our laboratory, will be used when the luminescence of the molecular probe is too low to be imaged with a reasonable signal/noise ratio. The two imaging time-domain systems will be developed in such a way that their detector will be gatable. This optional feature will be used to reject the prompt fluorescence while measuring the lifetime of the PPIX delayed fluorescence. This feature is important since the delayed fluorescence presents itself as another component of fluorescence besides the prompt fluorescence, but having a decay time equal to the lifetime of the triplet state of the pO2 molecular probe.In parallel to these instrumental developments, we plan to synthesize several pO2 molecular probes presenting very poorly toxic and phototoxic properties as mentioned above. This activity will be based on our extensive know-how for the screening and characterization of photosensitizes, as well as on our know-how in the filed of the production of nanoparticles-based formulations. The strategy we plan to adopt for this subproject will be to select nanoparticles materials such that molecular oxygen can easily diffuse in this material, whereas the singlet oxygen produced by the quenching process is “neutralized” within the nanoparticle, thus preventing the generation of photodamages to the tissues.We will test these pO2 measurements technique using "advanced" tissue models. More precisely, the preclinical studies will be performed with our chick’s chorioallantoic membrane (CAM) model and with an epidermal equivalent model. These two different models were chosen since the first one enables to study the toxicity as well as the vascular effects of photosensitizers, whereas the second is more adapted to study these effects at a cellular or tissular level.Following these preclinical studies, it is anticipated that the first clinical applications will be for the delineation of Martorell's ulcers using the MAL-induced protoporphyrin IX delayed fluorescence. This clinical translation will be based on the long-term and fruitful collaboration established between our group and the Dermatology Unit of University Hospitals.It should be noted that the clinical availability of an imaging system to monitor the tissular pO2 using poorly phototoxic molecular probes or the PPIX delayed fluorescence will also pave the way to many new diagnostic and therapeutic applications expected by the medical community.Finally, the innovative approaches we propose above to image the tissular and intracellular oxygen concentration will lead to new insights into the transport and consumption of oxygen in biological tissues, as well as regarding our understanding of the mechanisms taking place during various therapies, including PDT. These insights will be novel since the intracellular location of photosensitizers resides at sites pivotal in the transport and utilization of oxygen (mitochondria). Therefore, our results and novel techniques will probably open new research area in related scientific and medical fields.