A definitive conclusion about the dangers associated with human or animal exposure to a particular nanomaterial can currently be made upon complex and costly procedures including complete NM characterisation with consequent careful and well-controlled in vivo experiments. A significant progress in the ability of the robust nanotoxicity prediction can be achieved using modern approaches based on one hand on systems biology, on another hand on statistical and other computational methods of analysis. In this project, using a comprehensive self-consistent study, which includes in-vivo, in-vitro and in-silico research, we address main respiratory toxicity pathways for representative set of nanomaterials, identify the mechanistic key events of the pathways, and relate them to interactions at bionano interface via careful post-uptake nanoparticle characterisation and molecular modelling. This approach will allow us to formulate novel set of toxicological mechanism-aware end-points that can be assessed in by means of economic and straightforward tests. Using the exhaustive list of end-points and pathways for the selected nanomaterials and exposure routs, we will enable clear discrimination between different pathways and relate the toxicity pathway to the properties of the material via intelligent QSARs. If successful, this approach will allow grouping of materials based on their ability to produce the pathway-relevant key events, identification of properties of concern for new materials, and will help to reduce the need for blanket toxicity testing and animal testing in the future.

Multiple Sclerosis (MS) is the most frequent neuroinflammatory disease. Despite new treatments that slow the progression of the disease, patients with MS (PwMS) frequently evolve towards major disability. The pathogenesis of MS is controversially debated, but the recent discovery that infection with the Epstein-Barr virus (EBV) is a major risk factor will radically change research avenues. The BEHIND-MS consortium ambitions to understand how EBV promotes MS development. To this end, we have established a multidisciplinary team that will for the first time draw a comprehensive map of the interactions between the virus and all arms of the immune system in the blood and brain of PwMS and how they ultimately lead to neural damage, in the context of genetic risk factors. We will also develop an in vitro model of MS that integrates the virus, the immune system and brain cells reprogrammed from the blood of the same PwMS. Thus, for the first time, we will study in the laboratory the complex molecular mechanisms that give rise to MS. Finally, we will develop an animal model of prodromal MS that would be a ‘game changer’ for our understanding of MS pathogenesis and allow testing of promising new treatments. The pivotal knowledge developed in this project will empower the entire healthcare value chain to work towards better clinical management of MS. A detailed understanding of EBV-MS interactions, combined with newly identified biomarkers, and study models will open the doors for researchers, clinicians and industry to capitalize on the mechanisms underlying EBV-MS interactions, and develop new diagnostic, preventive and therapeutic tools and guidelines. Throughout the project, an open dialogue with the main stakeholder representatives will ensure a mutual understanding of patient needs and project results. Ultimately, by contributing to improved risk analysis, stratification and treatment strategies, BEHIND-MS has the potential to reduce the burden of MS on society.

Sleep is crucial to the brain’s remarkable regenerative and adaptive capabilities. Inadequate sleep is a pervasive problem that severely impairs brain function, productivity, and health. How the brain homeostatically senses sleep need and translates it into the intensified rebound sleep (RBS) that follows sleep deprivation (SD) still remains unclear. I aim to understand these mechanisms and to identify therapeutic targets that will promote consolidated, restorative sleep, enabling the development of superior sleep aids. Furthermore, this will shed light on the enigmatic yet fundamental question of the function of sleep. Astrocyte activation increases sleep, and astrocytes release adenosine (ado), a key messenger for sleep homeostasis. Thus, astrocytic-neuronal interactions likely decode sleep pressure into RBS via adenosinergic mechanisms. I discovered that cortical interneurons expressing neuronal nitric oxide synthase (nNOS) and neurokinin-1 receptor (NK1), which are selectively activated in RBS, show highly unusual excitatory responses to ado that are sensitive to sleep pressure. Furthermore, I found that knockout of a specific ado receptor in mice caused reduced numbers of cortical nNOS/NK1 neurons as well as a delayed RBS response. Based on these findings, I hypothesise that cortical nNOS/NK1 neurons play a key role in sleep homeostasis. My group now aims to 1) identify the comprehensive sleep homeostasis machinery, by building transcriptomic profiles of neurons activated during and after SD in mice using phosphorylated ribosome profiling, 2) verify the function of these newly identified neurons in sleep homeostasis by activity imaging and chemogenetic manipulation in vivo, and 3) investigate the functional role of astrocytes in the sleep homeostasis network. These studies will form the foundation for a new generation of sleep aids that are urgently needed to safeguard the productivity and health of our society.

The biological engineering project EMcapsulins will create the first suite of multiplexed genetic reporters for electron microscopy (EM) to augment today’s merely structural brain circuit diagrams (connectomes) with crucial information on neuronal type and activation history. My team will generate this new toolbox based on genetically encoded nanocompartments of the prokaryotic ‘encapsulin’ family that we have recently shown to enable genetically controlled compartmentalization of multicomponent processes in mammalian cells. By encapsulating metal-organizing cargo proteins in the lumen of the semi-permeable encapsulin nanospheres, they serve as fully genetic EM gene reporters (EMcapsulins) that provide robust and spatially precise contrast by conventional EM in mammalian cells. To enable geometric multiplexing in EM in analogy to multi-color light microscopy, we will explore the large geometrical feature space of EMcapsulins to establish three core Functionalities: ① different shell structures and diameters, ② modular and tunable shell functionalizations, and ③ multiplexed and triggered cargo loading. We will combine these Functionalities to produce geometrically multiplexed EMcapsulin markers of neuronal identity in serial EM (Application ❶). We will also engineer EMcapsulin reporters for activity-dependent gene expression, calcium signaling, and synaptic activity that can ‘write’ geometrically encoded records of neuronal activation history into EM connectomics data (Application ❷). These ‘multi-color’ and modular EMcapsulin markers and reporters deliver the missing bridging technology between time-resolved light microscopy measurements of neuronal activation dynamics and structural EM connectomics data. EMcapsulin technology will convert structural to functional EM connectomes to enable a systematic analysis of how brains write molecular signaling dynamics into structural patterns to store information for later retrieval.