Fig. 4.

(A) 3D confocal reconstruction of stromal-cells–laden GelMA stained for live and dead cells for the system with modulus ratio ${\mu }_f/{\mu }_s=4$ and prestretch ratio of the substrate ${\lambda }_{ps}=1.5,\hspace{0.17em}2,\hspace{0.17em}\text{and}\hspace{0.17em}2.5$ (substrate is not shown here). Green and red indicate live and dead cells, respectively. (B) Corresponding polar plot for the orientation angles and compressive strains of 150 randomly selected cells in each folded GelMA film shown in A. Blue asterisk indicates the average compressive strain and orientation angle. (C) Corresponding simulation results on contours showing the distribution of compressive principal strains in each folded GelMA film shown in A.