Patterning cell cultures using mechanical signals

A cell-stretching platform that can direct cell culture growth for more efficient drug screening.

The pneumatically actuated cell-stretching platform: (a) schematic illustration of the cell-stretching platform in the OFF state. (b) Schematic representation of the working principle of the device with output pattern 1 (OP1) and OP3 in the ON state. (c) FEA model results illustrating the OP1 and OP3 behaviour during the ON state. (d) Lower PDMS layer (4 × 2) with deformable output patterns and a control pattern. (e) Actual multilayer PDMS cell-stretching platform.

It is well known that cells respond to mechanical stimuli such as stress and strain. Mechanotransduction plays an important role in cell alignment, which is critical for cell homeostasis. Although many approaches have been developed in recent years to study the effect of external mechanical stimuli on cell behaviour, most of them have not explored the ability of the mechanical stimuli to engineer cell alignment to obtain patterned cell culture.

Prof. Nam-Trung Nguyen’s team at the Queensland Micro- and Nanotechnology Centre of Griffith University designed, fabricated and tested a pneumatically actuated 4×2 cell-stretching array with the help of ANFF-Q facilities.

“The device allows for concurrently inducing a range of cyclic normal strain onto cell cultures to achieve predefined cell alignment. We utilised ring-shaped normal strain pattern to demonstrate the growth of in-vitro patterned cell culture with predefined circumferential cellular alignment.” said  Harshad Kamble, the first author of this work.

“We show that novel tools such as our cell-stretching platform can be compatible with general tools and existing lab protocols. The dimensions of the cell-stretching array follow the standard F-bottom 96 well plate. Thus, conventional equipment can be used for sample handling and subsequent observation with microscopy” said Kamble.

Averaged cell orientation in degrees over the ROI for OP1 (a) and OP2 (b) with the corresponding 10× cell images of each ROI and the COMSOL strain distribution map. The scale bars are 100 μm.

After two hours of exercise in the platform, fibroblast cells arrange themselves into a patterned cell culture.

This cell-stretching platform is a potentially useful tool for drug screening in 2D mechanobiology experiments, tissue engineering and regenerative medicine.