A027 - Single-cell force spectroscopy to probe cell-cell interactions using AFM and AFM combined with microfluidics

Cécile Formosa (formosa@insa-toulouse.fr)
Sofiane El-kirat-chatel (elkirat1@univ-lorraine.fr)

Yeast cell-cell interaction is a fundamental step in the formation of biofilms. Many cell surface components can be involved in these interactions, such as specific adhesion proteins or cell surface polysaccharides. While these cell surface components are to some extent identified, little is known about the force and the nature of the interactions they form with their homologs or other molecules on opposite cell surfaces. Recent advances in atomic force microscopy techniques have enabled researchers to gain insight into the molecular interactions of microorganisms. In particular, the force spectroscopy-based technique called single-cell force spectroscopy (SCFS) has made it possible to understand the forces driving cell-cell interactions and biofilm formation. In this technique, a single microorganism cell is immobilized at the edge of a tipless cantilever, and used as a probe pushed against another cell immobilized on a surface. This technique has recently been implemented using AFM combined with microfluidics, where microfluidic cantilevers are directly connected to a pressure controller. In this case, a single cell can be aspirated at the aperture of a microfluidic cantilever, used for force spectroscopy measurements, and released afterward, allowing to catch another cell and repeat the process. This practical proposes to demonstrate how these two techniques can be used to measure, quantify and characterize the interactions between cells of the model yeast Saccharomyces cerevisiae. It is open to all scientists interested in cell-cell interactions of any type, and does not require any competences in AFM or biophysics.