Microfabricated platforms to investigate cell mechanical properties

Mechanical stimulation has been imposed on living cells using several approaches. Most early investigations were conducted on groups of cells, utilizing techniques such as substrate deformation and flow-induced shear. To investigate the properties of cells individually, many conventional techniques were utilized, such as AFM, optical traps/optical tweezers, magnetic beads, and micropipette aspiration. In specific mechanical interrogations, micro-electro-mechanical systems (MEMS) have been designed to probe single cells in different interrogation modes. To exert loads on the cells, these devices often comprise piezo-electric driven actuators that attach directly to the cell or move a structure on which cells are attached. Uniaxial and biaxial pullers, micropillars, and cantilever beams are examples of MEMS devices. In this review, the methodologies to analyze single cell activity under external loads using microfabricated devices will be examined. We will focus on the mechanical interrogation in three different regimes: compression, traction, and tension, and discuss different microfabricated platforms designed for these purposes.