Multi-modal MP microscope with AFM for cell mechanical investigations

• Subject Area: Physical Chemistry
• Term: Funded in 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 469988234

Mechanical interactions of cells with their environment are at the heart of many important phenomena in biology. This includes processes with strong mechanical involvement, like muscle contractions or tumour invasion, as well as areas where mechanical stimuli are more subtle, like embryogenesis and cell differentiation, yet where they play equally important roles.The envisioned microscope combines a number of techniques to enable fast, versatile, high-resolution, and minimally disruptive mechanical phenotyping. Specifically, the microscope comprises the following modalities:- confocal and multiphoton microscopy,- fluorescence lifetime imaging (FLIM),- traction force microscopy (TFM),- atomic force microscopy (AFM), - elastic resonator interference stress miscopy (ERISM),- photo-patterning by light-induced molecular adsorption of proteins (LIMAP).This will enable comprehensive and simultaneous characterization of1. the mechanical forces cells, tissue and organoids exert actively using (i) the ERISM technology developed in Prof Gather’s team, (ii) synthetic and genetically encoded tension sensors, and (iii) confocal traction force microscopy (TFM) including in thick specimen through multiphoton capability,2. the stiffness of cells, tissue and organoids using AFM, 3. the mechanical reaction of cells to (i) externally applied mechanical stresses using AFM, (ii) geometrical constraints and biochemical surface properties using LIMAP, and4. the 3D structure of cells, tissue slices and organoids and their local biochemical reaction (protein expression levels) to biochemical and biomechanical stimuli (using confocal/multiphoton imaging).This innovative, multi-modal approach will allow imaging and manipulation of cell forces and matrix stiffnesses with high resolution and in real-time. It will thus provide unprecedented experimental access to the processes underlying cell mechanics and mechano-transduction which is vital to the recently founded Centre for NanoBioPhotonics and overlaps with the focus of a number of interdisciplinary research initiatives and excellence clusters located at the University of Cologne (UoC) and external research institutions; in particular at CECAD, at the Collaborative Research Centre 829 (“Molecular mechanisms regulating skin homeostasis“), and at the Clinical Research Unit 329 (“Molecular mechanisms of podocyte diseases”). In addition, the facility will spur new cooperation within the Department of Chemistry, e.g. between the Centre for NanoBioPhotonics and the Institutes of Organic Chemistry and Biochemistry on molecular and genetically encoded molecular FRET-tension sensors, or the Institute of Physical Chemistry on development of nanoparticles for external stress application on cells. The microscope will thus have substantial synergetic impact that reaches into a wider part of the university and to external research institutions.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Multimodales MP Mikroskop mit AFM für zellmechanische Untersuchungen
• Instrumentation Group: 5090 Spezialmikroskope
• Applicant Institution: Universität zu Köln
• Leader: Professor Dr. Malte Gather