High-Throughput Imaging of Cellular Dynamics Using Microfabricated Platforms Based on a Cell-Friendly Photoresist

Many biological processes in multi-cellular organisms are regulated by various dynamic cellular processes. However, classical tissue culture system can only provide static environments where many dynamic events occur randomly, thus mechanistic study of dynamics of cellular dynamics has been limited. To overcome this limitation, we developed new experimental platforms where we can precisely position different types of cells and control their movement by illuminating light to predefined areas. A thin film of a cell-friendly photoresist PDMP (poly(2,2-dimethoxy nitrobenzyl methacrylate-r-methyl methacrylate-r-poly(ethylene glycol) methacrylate) was used. Upon UV exposure, PDMP thin films become soluble in near-neutral aqueous buffers such as PBS and tissue culture media with minimal cytotoxicity. To create micro-patterns on PDMP thin film, microscope projection photolithography (MPP) technique was used. By performing series of MPP on PDMP thin films and sequentially depositing cells on UV-irradiated regions, we could successfully create single cell arrays of adhering cells. Then, various dynamic cellular processes such as cell spreading, adherens junction formation, and collective cell migration were triggered by removing PDMP thin films surrounding cells in single cell arrays by UV illumination. Using this new dynamic cell-patterning technique in conjunction with an automated microscope equipped with a motorized stage, dynamics of each cellular process was imaged in high-throughput manners to collect large amounts of data in a single experiment. This method can be useful for screening drugs targeting dynamic processes of cells.