Beyond the paradigm of nanomechanical measurements on cells using AFM: an automated methodology to rapidly analyse thousands of cells

International audienceNanomechanical properties of cells could be considered as cellular biomarkers. The main method used to access the mechanical properties is based on nanoindentations measurements, performed with an operator manipulated Atomic Force Microscope (AFM) which is time-consuming, and expensive. This is one of the reasons preventing the transfer of AFM technology into clinical laboratories. In this presentation we report a methodology1 which includes an algorithm (transferred to a script, executed on a commercial AFM) able to automatically move the tip onto a single cell and through several cells to record force curves combined with a smart strategy of cell immobilization. Cells are placed into microwells of a microstructured polydimethylsiloxane (PDMS) stamp. Inside a classical 100x100 µm2 AFM field, 80 to 100 cells are immobilized. In an optimal configuration we were able to measure a population of 900 Candida albicans cells both unmodified and caspofungin treated in 4 h, which represents an unprecedented performance2. This strategy can be applied to cell arrays, proteins or glycan arrays. The big amount of data generated is compatible with the analysis by machine learning and will most probably generate unexpected understanding of the biological processes.References (max. 5): 1. Severac C.,, Proa-Coronado S., Formosa-Dague C., Martinez-Rivas A., Dague E. 2020 in Press Automation of Bio-Atomic Force Microscope Measurements on Hundreds of C. albicans CellsJournal of Visualized Experiments e61315 URL: https://www.jove.com/video/61315 doi:10.3791/61315 2. Proa-Coronado S., Severac C., Martinez-Rivas A., Dague E. 2019Beyond the paradigm of nanomechanical measurements on cells using AFM: an automated methodology to rapidly analyze thousands of cells.Nanoscale Horizons, DOI : 10.1039/c9nh00438fAcknowledgment: We want to acknowledge FONCYCYT of CONACYT (Mexico), the ministry of Foreign affairs of France and the Universit ́e Paris 13, though the financial support of the international collaborative ECOS-NORD project named Nano-palpation for diagnosis, No. 263337 (Mexico) and MI5P02 (France). AMR would like to thank the financial support of the SIP project No. 20195489, from IPN. SPC is supported by a PhD fellowship from CONACYT (No. 288029) and IPN through the cotutelle agreement to obtain double PhD certificate (IPN-UPS). ED is a researcher at Centre National de la Recherche Scientifique (CNRS)