Choose timezone
Your profile timezone:
Powered by Indico
v3.3.4
Since its first construction by Gerd Binnig, Calvin F. Quate, and Christoph Gerber in 1986 [1], it took only a few years to disclose the tremendous potential of atomic force microscopy (AFM) in the research of biological objects [2]. It is mainly because AFM does not need sample modification and labelling. Freedom of selection of conditions, including performing measurements in culture media, control of pH, and temperature combined with large x,y, and z piezo-scanner ranges all have led to the rapid development of live cell imaging. Finally, novel AFM imaging modes, based on a fast acquisition of force-distance curves, have enabled 4D (3D plus time) imaging of changes in biological samples. During the presentation, the results of the development of so-called in vitro pharmacology on a single cell will be presented [3]. Briefly, single-cell morphology and its nanomechanical properties are tracked over time. Then, a drug is injected into the culture medium and the cell response to the drug is further observed. It allows monitoring of morphological features and the cytoskeleton remodelling, including its effect on alterations in Young’s modulus distribution.
The main focus of the presentation will be devoted to primary murine liver sinusoidal endothelial cells (LSEC) in vitro. LSEC have transcellular pores, called fenestrations, that are indicators of the healthy phenotype of the liver. These nanostructures – 50-350 nm in diameter – participate in the transport of lipoproteins and solutes (e.g. hormones) between the vascular system and the liver parenchyma. AFM remains the exclusive tool allowing monitoring of drug response in living LSEC for up to 6 hours. Fenestration number, diameter, lifespan, migration range, and deformability can be quantified. Moreover, Young’s modulus distribution over the whole cell can be calculated [4]. Being a label-free method AFM does not provide any chemical information about the investigated samples. The direct correlation with other super-resolution optical nanoscopy methods, such as: structured illumination microscopy (SIM), stimulated emission-depletion microscopy (STED), and scanning electron microscopy (SEM) will be presented. All to provide a multi-parametric approach to imaging at the nanoscale [5].
[1] Binnig G., Quate C.F., Gerber C., Phys. Rev. Lett., 1986, doi. 10.1103/PhysRevLett.56.930.
[2] Radmacher M, et al., Science 1992, doi. 10.1126/science.1411505.
[3] Zapotoczny B. et al., Hepatology, 2019, doi. 10.1002/hep.30232;
[4] Zapotoczny B. et al., Biophysical Reviews, 2020, doi. 10.1007/s12551-020-00699-0;
[5] Szafranska K.,[...], Zapotoczny B. Nanophotonics, 2022. doi. 10.1515/nanoph-2021-0818;