Micropatterning Hydroxy-PAAm Hydrogels and Sylgard 184 Silicone Elastomers with Tunable Elastic Moduli.

This protocol describes the microcontact printing method on two complementary polymer substrates, that permit together to control cell shape and spreading area over a wide range of matrix stiffnesses (three orders-of-magnitude). In the first part, we introduce a novel polyacrylamide hydrogel, called hydroxy-PAAm, that permits to surmount the intrinsically non-adhesive properties of polyacrylamide with minimal requirements in cost or expertise. We describe a protocol for tuning the rigidity of 'soft' hydroxy-PAAm hydrogels between ~0,5-50 kPa and a micropatterning method to locally deposit proteins on these soft hydrogels. In a second part, we describe a protocol for tuning the rigidity of 'stiff' silicone elastomers between ~100-1000 kPa and a micropatterning method to locally deposit proteins on these stiff elastomers. Finally, we report experiments performed on both substrates that have been conducted to investigate the effect of the matrix rigidity on the nuclear shape remodelling process of micropatterned endothelial cells.