The Impact of Experimental Conditions on Cell Mechanics as Measured with Nanoindentation

Abstract

The evaluation of cell elasticity is becoming increasingly significant, since it is now known that it impacts physiological mechanisms, such as stem cell differentiation and embryogenesis, as well as pathological processes, such as cancer invasiveness and endothelial senescence. However, the results of single-cell mechanical measurements vary considerably, not only due to systematic instrumental errors but also due to the dynamic and non-homogenous nature of the sample. In this work, relying on Chiaro nanoindenter (Optics11Life), we characterized in depth the nanoindentation experimental procedure, in order to highlight whether and how experimental conditions could affect measurements of living cell stiffness. We demonstrated that the procedure can be quite insensitive to technical replicates and that several biological conditions, such as cell confluency, starvation and passage, significantly impact the results. Experiments should be designed to maximally avoid inhomogeneous scenarios to avoid divergences in the measured phenotype.

The Revolution in Breast Cancer Diagnostics: From Visual Inspection of Histopathology Slides to Using Desktop Tissue Analysers for Automated Nanomechanical Profiling of Tumours

“…Several attempts have been made to provide diagnostic tools that allow for cancer detection [ 49 , 50 , 51 , 52 , 53 , 54 , 55 ]. One interesting tool that aims to detect cancer is the Optics11Life device [ 56 , 57 ]. However, its micrometre-sized tips may be too big to measure the important clinically relevant information.…”

An Assessment of the Mechanophysical and Hormonal Impact on Human Endometrial Epithelium Mechanics and Receptivity

“…Cells and probe tips were placed in the incubation chamber at least 30 min prior to taking measurements to avoid measurement errors due to temperature drift. To keep experimental parameters as standardized as possible [51], we performed the measurements with similar cell passages, identical numbers of cells for seeding, comparable confluences, identical cell culture media, identical surface coatings, and the same individual handling the cells. Single cells in confluent monolayers were measured by placing the probe tip above the cell center.…”

A Review of the Current State of Magnetic Force Microscopy to Unravel the Magnetic Properties of Nanomaterials Applied in Biological Systems and Future Directions for Quantum Technologies

“…The AFM tip works as an indenter to exert an elastic deformation on the tested surface sample. Nanoindentation was employed to measure the elastic properties of living cells [ 88 ], collagen fibrils [ 89 ], and biopolymers under different relative humidity [ 90 ], and to monitor the decay of cellular nanomechanics in diseases like cystic fibrosis [ 91 ] or cancer [ 92 ], together with drug-targeting effectiveness [ 93 ]. Finally, AFM based on nanoscale infrared spectroscopy (AFM-nanoIR) enables the mapping of chemical composition and topography or determination of the full IR spectra at specific sample locations [ 94 ].…”