Dysregulated interactions between biomolecules can lead to changes in cell signalling and gene expression, both common drivers of human disease. A detailed understanding of these interactions is vital for drug development, often targeting such interactions for therapeutic effects. In this project, I aim to develop an optical microscopy tool to observe interactions of highly diverse biomolecules in terms of e.g. weight or size, in real-time on a single-molecule level without the use of labels or immobilization, which limits many current established methods. This will allow the study of dynamic interactions between complex biomolecules of varying sizes and with a wide range of properties. The tool will be capable of researching various biological systems that are not easily accessible by established methods. This could contribute to breakthroughs in the research of severe diseases such as diabetes mellitus, Alzheimer's, or Parkinson's disease.

Vectorization of biologically active molecules for their selective delivery to target cells is a major objective since this strategy allows potentiating the activity of these molecules, but also limiting their side effects. In particular, selective addressing of antigens of vaccinal interest to dendritic cells represents an active field of investigation and is particularly promising for the development of new candidate vaccines against infectious agents or cancers. Indeed, the dendritic cells are the only cells of the innate immune system able to activate the naive T cells, which is indispensable to induce protective adaptive immune responses. According to their phenotype, ontogeny, localization and specialized functions, dendritic cells are divided into different subpopulations, including lymphoid, myeloid and plasmacytoid subsets, identified both in mice and humans. A large body of data shows that the level of adaptive immune responses, differentiation and specialization of CD4+ Th1, Th2, Th17, or regulatory T cells, as well as activation of CD8+ T cells are orchestrated by various sub-populations of dendritic cells. Therefore, the in vivo mobilization and activation of the latter by their direct targeting through specific surface markers, represents a critical way for the development of preventative and/or therapeutic vaccine candidates against cancers or infectious diseases. We have recently developed a vectorization technology to address one or more biologically active molecules, including antigens and/or adjuvants, in a highly versatile manner, to various target cells and in particular to dendritic cell sub-populations. Unlike other technologies developed to date, our strategy allows the addressing of biologically active peptidic or non-peptidic compounds to well-defined dendritic cell subsets. Indeed, these compounds can be polypeptides, sugars, lipids or oligonucleotides of large size. Application of this technology to vaccination will enable to deliver in a highly specific and well-controlled manner, necessary and sufficient amounts of antigens and adjuvants to the same sub-population of dendritic cells, selected as a function of the type of the adaptive immunity to be induced. This will allow inducing optimal and ultimately protective immune responses, without undesirable inflammatory responses, frequently related to administration of adjuvant. We have established the proof-of-concept and feasibility of this approach in different experimental models, ranging from synthesis and purification of vectorized molecules until in vivo induction of adaptive immune responses. All of these results gave rise to a European patent application in December 2009. Our current project aims to reinforce the results obtained, in order to substantiate claims of the patent and strengthen intellectual property protecting the developed technology. Furthermore, the objective of our project is the implementation of our technology for the development of effective therapeutic and/or prophylactic vaccines in priority areas in public health and economic level, such as adult pulmonary tuberculosis and cancers due to chronic Human Papillomavirus (HPV) infection. The present proposal will lead to a rapid valorization of this technology at the industrial level.

The coherent extreme ultra violet (EUV) pulses produced via high harmonic generation (HHG) in gases are now the main workhorse for various applications of atomic physics and physical chemistry. As the generation efficiency is very low, the number of applications is limited by the low EUV photon flux. The main ambition of this project is to perform a coherent parametric amplification of the EUV pulses in order to significantly increase the EUV photon flux. Such an achievement would be an enabling technology causing a breakthrough in the field of atomic physics, physical chemistry, biology, material science and probably other fields as well. Applications suffering from poor signal/noise ratio will become widespread as they will not be limited anymore to research labs where the EUV sources are optimized daily. Moreover, higher photon flux opens completely new physics, as the EUV nonlinear optics becomes widely accessible and two-EUV-photon absorption turns out to be routine. Very recently a theoretical study was published on high order parametric generation based on the same number of infrared photons absorbed as in “standard” HHG. However, in contrast to HHG, 3 photons are emitted. We have already obtained preliminary data that suggest the presence of EUV photons of slightly lower energies than those originating from HHG. The photon energy difference corresponds to two photons from THz part of the spectrum and is in agreement with the theory. In the project, we identify our major objectives as work packages: WP1: Detection and optimization of the parametric EUV signature in HHG EUV spatially-resolved spectra. WP2: Study on detection of the THz field originating in HHG. WP3: Injection of externally generated THz beam to boost the high parametric process leading to amplification of EUV.

It sounds simple: A cell cannot divide without nucleotides. Indeed, the disruption of pyrimidine de novo synthesis (PDNS) efficiently blocks proliferation of cancer cells. Yet still today, PDNS-directed anticancer treatment has not entered clinics due to the lack of efficacy. Why? Cancer cells gain pyrimidines via PDNS or from salvage pathways, and PDNS inhibition in cancer cells can likely be bypassed by pyrimidines produced in the tumor environment or gained from the systemic circulation. Can we target this microenvironmental interaction to improve treatment efficacy? A crucial component of tumor environment are blood vessels. Tumors stimulate their growth, angiogenesis, to gain oxygen and nutrients. Metabolism of endothelial cells (ECs), the inner vessel lining, is rewired in tumors, and tumor ECs upregulate PDNS. However, whether and how elevated PDNS in ECs supports tumorigenesis is unknown. I hypothesize that PDNS in ECs affects tumor environment either directly by providing pyrimidines to cancer cells or indirectly by stimulating angiogenesis, making systemic resources more accessible to cancer cells. The central goals of this project are (i) to identify the metabolic communication of ECs with other cell types in tumors, (ii) asses if endothelial PDNS promotes angiogenesis, and (iii) to seek novel metabolic targets in ECs, whose inhibition improves efficacy of PDNS inhibitors in vivo. To reach these goals, I will use an inducible mouse model to selectively disable PDNS in the endothelium. With this unique tool available at my host institute, I will integrate a state-of-the-art multi-omics and my expertise in metabolism to disentangle the network of metabolic communication using a powerful combination of spatially resolved single cell transcriptomics, metabolomics and functional genomics. My innovative approach will open a way for understanding the EC contribution to metabolic balance in tumors with a potential to identify new metabolic anti-cancer strategies.