Fiber photometry allows the activity of molecularly defined neuronal populations to be measured in freely behaving animals. The method is based on an implanted optical fiber through which fluorescent genetically encoded indicators of cellular activity, metabolites or signaling molecules can be monitored and is widely used in neuroscience research. However, conventional photometry systems are not flexible and typically limited to a fixed configuration of one or two readout channels. We will develop a new product based on a radically redesigned concept of fiber photometry called Fused Fiber Photometry (FFP). This new design is highly flexible and allows the fiber photometry setup to be easily reconfigured to a large number of spectral configurations at low cost. Furthermore, by combining spectral detection with spectral control of the fluorescence excitation signal, we will realize hyperspectral fiber photometry. Fused fiber photometry and hyperspectral photometry have the potential to gain large attraction in the academic research, industrial R&D and manufacturing processes, and in medical diagnosis. The technique has therefore high commercialization potential and a competitive advantage over existing commercial systems. It allows companies to offer a simple, out-of-the-box, turnkey system that can be easily modified and upgraded to meet user requirements. Our goal is to develop a commercializable hyperspectral fiber photometry system based on FFP. We will work hand in hand with established industrial partners to bring the system to market. By realizing HyFiPhotometry in this PoC project, want to exploit the full potential of hyperspectral photometry and demonstrate the feasibility of the basic idea. In the long term, we aim it to drive inventiveness in the fields of biomedical research, medicine and beyond. In this way, we expect to move our product from the niche of neuroscience to a wide range of applications that are highly relevant to society.

Heart failure remains a leading cause of mortality worldwide taking an estimate of 16 million lives each year. Cardiac tissue engineering solutions that can improve the quality of life of those with advanced heart disease have proved challenging so far. Bioprinting is an exciting technology that holds promise to fabricate tissues and organs. Lab-grown engineered cardiac muscle requires at least four weeks to maturate in a bioreactor. In LIGHTHEART, an off-the-shelf solution will be developed for treating injured myocardium in vivo. An unconventional combination of bioprinting and optogenetics will be used to surgically fabricate engineered cardiac muscle directly at the patient’s heart. A surgical bioprinting tool will be constructed to achieve vascularization and cellular architectures as that observed in native cardiac muscle. Induced pluripotent stem cell-derived cardiac cells will be the basis of the bioinspired biomaterial-free ink that will be printed. Optogenetic expression of different light-sensitive proteins at the cell surfaces will be the sole trigger of cellular assembly, thus omitting the need to embed cells in hydrogels or printing in a supporting bath. Surgical optogenetic bioprinting will be first tested ex vivo using a silicone human phantom with a mimicking beating heart, and later in vivo in a large animal model in accordance with the 3R principles. LIGHTHEART opens up new horizons in the way heart failure can be clinically treated and brings hope to patients who are desperately waiting for a heart transplantation. The disruptive nature of LIGHTHEART will unite engineers, surgeons and scientists to change the future of transplantation medicine with modular bottom-up technologies that allow for in vivo tissue and organ restoration or replacement directly at the operating theatre.

The relaxation of electronically excited systems like atoms and molecules embedded in environment is a key question in chemistry and photobiology and the underlying physical mechanisms have been widely studied. The applicant has predicted theoretically that there are two efficient electronic processes between a system and its neighbors even if the system itself is in its electronic ground state and does not have excess energy, making clear that an important gap exists in our current understanding of systems embedded in environment. There is extensive future potential in filling this gap and we aim at exploring and exploiting it in systems of physical, chemical, and biological interest. The discovered electron-transfer mediated decay (ETMD) [several variants of ETMD have been already verified experimentally] and intermolecular Coulombic electron capture (ICEC) mechanisms give rise to a plethora of surprising electronic phenomena relevant to many fields. In radiation damage, for instance, differently charged cations and electrons are produced by ionization and Auger processes, and ETMD and ICEC continue to be operative, neutralize cations and produce radicals in the environment also after the known mechanisms of radiation damage have ceased to operate. This leads to severe additional damage. Knowing the factors influencing the impact of ETMD and ICEC most, we can exploit this knowledge to be able to suppress or enhance this impact. Such a control is invaluable in many cases, may be even in radiation therapy. We are certain that the novel and fundamental ETMD and ICEC processes can be exploited to probe and control systems embedded in an environment. Such a breakthrough necessitates the advancement of current methodologies far beyond the state-of-the-art, and can only be achieved by the close collaboration of a highly motivated strong team of scientists over a long period of time. The support by the ERC will substantially contribute to the realization of this vision.