Mechanical Effect on Gene Transfection Based on Dielectric Elastomer Actuator

Abstract

Gene transfection has been widely applied in genome function and gene therapy. Although many efforts have been focused on designing carrier materials and transfection methods, the influence of mechanical stimulation on gene transfection efficiency has rarely been studied. Herein, dielectric elastomer actuator (DEA)-based stimulation bioreactors are designed to generate tensile and contractile stress on cells simultaneously. With the example of the EGFP transfection, cells with high membrane tension in the stretching stimulation regions had lower transfection efficiency, while the transfection efficiency of cells in the compressing regions tended to increase. Besides, the duty cycle and loading frequency of the applied stress on cells were also important factors that affect gene transfection efficiency. Furthermore, the pathways of cell endocytosis with the effect of mechanical stimulation were explored on the mechanism for the change of EGFP transfection efficiency. This design of the DEA-based bioreactor, as a strategy to study gene transfection efficiency, could be helpful for developing efficient transfection methods.

Physical and mechanical cues affecting biomaterial-mediated plasmid DNA delivery: insights into non-viral delivery systems

“…It is not clear whether it was a different stimulus (e.g. uniaxial stretching versus compression [38]/equiaxial stretching) [219] or rather an excessive mechanical tension (independent on the type of loading) [207, 224, 225, Stretching or compression (compressing ratio 2%, 4%, 6% and stretching ratio 4%, 8%, 12%, 30, 60 and 100% duty cycle, 2, 10, 100, 1000 mHz, for 10 min)…”

“…Inhibition of clathrin-mediated route by chlorpromazine [17,37,38], of caveolae using methyl-β-cyclodextrin [17], ,genistein [38] or filipin III [37], of micropinocytosis using amiloride or wortmannin [38] decreased transfection efficiency, to a different extent depending on complex type. In general, when cholesterol and DOPE were utilised [33], internalisation of liposomes were cholesterol sensitive [39,40].…”

“…Similarly, A549 cells, subjected to equibiaxial stretching on silastic membranes, reorganised their cytoplasm, appeared more rounded than their unstretched counterparts and were more efficiently transfected via electroporation [ 222 ]. By using a dielectric elastomer actuator (DEA)-based stimulation bioreactors to generate tensile and contractile stress, in A549 cells, optimised cell compression (in terms of frequency and duty cycle) had a promoting effect, whereas different stretching regimens showed an inhibitory effect on transfection [ 38 ]. Although molecular mechanisms were not investigated, the decrease of gene transfection in stretched—as opposed to compressed—cells could be attributed to caveola flattening and disassembly, which was proven to be a consequence of excessive mechanical tension [ 224 , 225 ].…”

“…A 40% decrease in transfection efficiency was observed in stretched samples, compared to non-loaded control. [ 38 ] Ultrasound-induced mechanical stress (50 pulses of 250 μ s in duration and 600 V in amplitude), combined with high electric field (electroporation) In vivo rabbit retinas and in vitro chorioallantoic membrane Naked DNA added during stimulation 1000-fold increase in photons/s indicating a higher expression of the marker gene luciferase in samples subjected to ultrasound and electroporation treatments, compared to samples subjected to electroporation alone. [ 221 ] Equibiaxial cyclic stretch (10% area stretch, 50% duty cycle, 0.5 Hz, time variable from 30 min to 24 h) A549 on Pronectins™-treated plates Electroporation of naked DNA, performed before mechanical loading Twenty-four hours of cyclic stretch induced a onefold to sixfold increase in transfection, compared to non-loaded control [ 222 ] Equibiaxial stretch, either continuous or cyclic (10% area stretch, 10% duty cycle, 1 Hz, either 30 min or 24 h) A549 on laminin-coated plates Naked DNA, or lipoplexes composed of Lipofectin™ (Thermofisher) or electroporation.…”

Enhanced Electromechanical Property of Silicone Elastomer Composites Containing TiO2@SiO2 Core-Shell Nano-Architectures

“…[ 7 , 8 ]. All these features endow DE materials with a great application potential in bioinspired tunable optical lens [ 9 ], micro-optical submount [ 10 ]; energy generator from human motion [ 11 ] and sea wave [ 12 ], flexible robotic arm [ 13 ], software robot [ 14 ], electric-fish-inspired actuator [ 15 ], gene transfection driver [ 16 ], soft logic switch [ 17 ], etc.…”