Capturing Transient Responses – Combining BioAFM with External Stimulation

A. Gelmi
RMIT University,

Keywords: AFM, FluidFM, stem cells, biomaterials


Adult stem cells reside quiescently in vivo, awaiting stimuli to trigger the journey towards a mature functional cell. Stem cells respond to external cues in the body when recruited for tissue repair or regeneration. Similarly, external stimulation can be applied in vitro to stem cells to induce a specific outcome (i.e. bone tissue regeneration or cartilage formation).[1] For example, electrical stimulation delivered via a conductive biomaterial induces multi-lineage stem cell differentiation.[2] This is a very promising area of tissue engineering, however understanding how these external stimuli provoke targeted differentiation is still unclear. Atomic force microscopy (AFM) is gaining recognition as a powerful tool for live cell analysis, and as new techniques are developed we can not only capture biomechanical properties of live cells, but also biochemical. Here I will present our work using advanced bioAFM to capture highly resolved biomechanical analysis of living stem cells in response to external stimulation, quantifying changes in cytoskeletal features and Young’s modulus in context to both chemical and physical triggers. The biomechanical properties of stem cells are closely linked to differentiation,[3] and through exploring the mechanobiology of stem cells with AFM we can better harness external stimulation for tissue engineering. Furthermore, with new technologies such as the CytoSurge FluidFM, we can perform single cell biopsies on living stem cells to track biochemical changes over time as the cells response to external stimuli. Using our custom external stimulation platforms integrated with our bioAFM, this will enable us to be the first to track biochemical changes in living stem cells in response to external stimulation. [1] Gelmi and Schutt. Stimuli-Responsive Biomaterials: Scaffolds for Stem Cell Control. Adv. Healthcare Mater. 2020, 10 [2] Thrivikraman, et al. Unraveling the mechanistic effects of electric field stimulation towards directing stem cell fate and function: A tissue engineering perspective. Biomaterials 2018, 150 [3] Kilian, et al., PNAS 2010, 107 (11)