Cellular mechanical properties are known to influence both their cellular and subcellular functions. Whilst methods to assess cellular mechanics such as Atomic Force Microscopy (AFM) are already available, there is an emerging need to measure cellular mechanical properties in a label-free and contactless mode, to allow for long time monitoring of cell behaviour, and to enable measurements of cells embedded in extracellular matrix. In this study, we have employed Digital Holographic Microscopy (DHM) combined with the well-controlled application of hydrostatic pressure to study cellular mechanical properties in real-time and in a noncontact manner. Cyclic stress was applied non-destructively and non-invasively to pancreatic ductal adenocarcinoma Focal Adhesion Kinase (FAK) knockout cells (Panc47-1 -/-null) and their corresponding re-expressing clonal population (Panc47-1 +/+ wild type) within a 25cm2 culture flask by a microfluidic pump 24h after seeding. Cyclic stress was successfully applied directly to cells, and corresponding change in volume was recorded in real-time at the nanometre scale for cell, yielding the mechanical properties of the cells. Change in amplitude and/or frequency of the stimuli was translated to corresponding cell response. Differences were observed in relative strain rates between the cell lines under investigation. We have described a novel method to perform optical elastography on live cells at single cell resolution in realtime and non-destructively. This allows for long-term monitoring of mechanical properties during cell proliferation and differentiation, and disease progress. This can be directly related to the biomechanical properties of cells.
There is an unmet need in tissue engineering for non-invasive, label-free monitoring of cell mechanical behaviour in their physiological environment. Here, we describe a novel optical coherence phase microscopy (OCPM) set-up which can map relative cell mechanical behaviour in monolayers and 3D systems non-invasively, and in real-time. 3T3 and MCF-7 cells were investigated, with MCF-7 demonstrating an increased response to hydrostatic stimulus indicating MCF-7 being softer than 3T3. Thus, OCPM shows the ability to provide qualitative data on cell mechanical behaviour. Quantitative measurements of 6% agarose beads have been taken with commercial Cell Scale Microsquisher system demonstrating that their mechanical properties are in the same order of magnitude of cells, indicating that this is an appropriate test sample for the novel method described.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.