Developing Protective Strategies to Mitigate Cellular Disruption by Radicals During Photopatterning
Laura Hockaday Kang,
Postdoctoral Researcher,
Institute of Cell Dynamics and Imaging
Hydrogels can be tailored to simulate the 3D micro-environment cells experience in their natural niche, making them attractive to both tissue-engineers and biologists for 3D encapsulation of living cells. Photo-polymerizable hydrogels are particularly promising because photocrosslinking enables rapid fabrication and spatial control during solidification and also allows generation of micron-scale features using 3D printing additive manufacturing strategies. One critical barrier to the effective use of photocrosslinking and 3D printing in tissue engineering is cytotoxicity associated with photoinitiator radicals, in particular the highly variable damage and oxidative stress experienced by different cell types during exposure. Investigators have previously shown that chondrocytes allowed to form a pericellular matrix prior to exposure exhibit better membrane integrity and function following photoinitiator radical exposure compared to cells simply suspended in precursor solution and exposed[1,2]. To mimic this protective layer for non-chondrocyte and sensitive cell types, emulsion droplet-generating microfluidics were used to create hydrogel shells around cells. Shelled-cells were then patterned into photo-polymerized methacrylate-gelatin structures. Impact of photoinitiator radical exposure on cell plasma-membrane integrity and lipids was assessed with propidium iodide and ImageIt lipid peroxidation reporter. To assess dynamic changes to cortical actin, Lifeact expressing 3T3 cells were imaged live during photoinitiator activation and hydrogel solidification.
|
|
