Mechano-regulatory cellular behaviors of NIH/3T3 in response to the storage modulus of liquid crystalline substrates.

The extent of substrate stiffness has been shown to be predominant in regulating cellular behaviors. Previous studies have used matrices such as elastomers or hydrogels to understand cell behavior. Herein, liquid crystalline matrices that resemble movable morphology of biomembrane and viscoelasticity were fabricated with tunable storage modulus for the evaluation of the modulus-driven cell behaviors. Our results demonstrated that NIH/3T3 cells showed a hypersensitive response to the storage modulus of liquid crystalline substrates by the alteration in attachment, spreading, proliferation and viability, polarization, cell cycle and apoptosis, and activity of mechano-transduction-related signal molecules including FAK, paxillin and ERK. The octyl hydroxypropyl cellulose substrates (OPC-1-5) with intermediate storage modulus of 12,312Pa and 7228Pa (OPC-2 and OPC-3 respectively) could provide more beneficial adhesion conditions leading to a larger spreading area, more elongated morphology and higher proliferation rates possibly through paxillin-ERK pathway, whereas the substrates with the highest or lowest storage modulus (16,723Pa, OPC-1; and 41Pa, OPC-5, respectively) appeared unfavorable for cell growth. Our study provides insights into the mechanism of modulus-driven cellular behaviors for better design of bioengineered cell substrates.