Nanoneedles for intracellular probing – NanoIntra

Over the past decade, cell behavior on arrays of vertical nanostructures has been the focus of numerous studies aimed at evaluating these as tools for manipulating and probing single cells. Such arrays of high-aspect-ratio objects have proven to be largely compatible with mammalian cells and are currently being established as platforms for a wide variety of advanced applications. Among these nanoobjects, NanoNeedles (NNs) have rapidly emerged as a tool to interact with the intracellular environment of a large number of cells simultaneously, with limited perturbation of their physiological processes. This interaction provides characteristic advantages for minimally invasive cell and molecular biology investigations, as well as progression of biomedical translation of regenerative and precision medicine approaches. A quick string of several successful proofs of principles have established NNs' potential to efficiently deliver impermeant molecules as well as nanoparticles directly to the cell cytosol, and to sense the intracellular milieu across biological systems ranging from cells in culture to living organisms.
With increasing life expectancy, neurodegenerative diseases such as Alzheimer’s disease (AD) are expected to affect an ever increasing number of people potentially putting severe strain on healthcare systems around the world. AD is expected to affect 1 on 85 people worldwide by 2050. Preventing Tau (tubulin-associated unit) aggregation is a potential strategy to cure neurodegenerative disorders associated with Tau. Tau is a neuronal protein regulated by phosphorylation/dephosphorylation events involved in the AD propagation via cell to cell and brain region to brain region Tau transportation. Due to its pathological significance, Tau became an important therapeutic target. In vitro cell-based models are thus crucial to investigate the intracellular Tau modifications (mainly phosphorylation), aggregation and propagation mechanisms. Such studies will permit not only to identify new therapeutic biomarkers but also to screen and evaluate drug candidates. In this project, in order to precisely detect Tau and its post-translational modifications in the intracellular compartment, we are proposing to develop a very innovative and minimally invasive nanoneedle based method for monitoring living cells by leveraging the ability of NNs for both: accessing the cell cytoplasm and performing surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) investigation of intracellular compartment, thus aiming to get new insights in the understanding of biochemical processes occurring within cells.
The technological challenge here is thus to fabricate vertically ordered NNs enabling both the cell penetration while maintaining the cell integrity and the SALDI-MS detection of intracellular biomolecules. NanoIntra project will permit the development of new type of powerful analytical tool based on MS detection of various biomarkers and enzymatic activities directly within cells.
This project is inscribed in many fields of scientific and research activities. Indeed, while biology and physiology concern the mechanisms of life at different levels: molecular, cellular, tissue and systemic, chemistry and physics, for their part, challenge the mastery and the fabrication of new objects, e. g. nanomaterials with new properties. The formalization of the living and the development of new innovative tools for life science analysis and precision medicine will favor all therapeutic, diagnostic and biomedical applications. The implementation of innovative and competitive research projects, will help us to structure the community of actors (research, medicine...), to support the regionalization of the R&D activities of the health industries and to increase the attractiveness of research of the "Hauts-de-France region".