Figure 2.

The Shape of iPSC Colonies Is Controlled by Submicron Topography

(A) Phase-contrast (top) and scanning electron microscopy images (bottom) of round and elongated iPSC colonies on PI flat and PI 650, respectively. Scale bars, 40 μm.

(B) Aspect ratio of the colonies either 24 or 48 hr after seeding (n = 3 independent biological replica; ^∗∗p < 0.01, ^∗∗∗p < 0.001, unpaired Student's t test). Data are presented as mean ± SD.

(C) Representative images showing how topography directs the cell division plane perpendicularly to the submicron grooves; inlay highlights a mitosis. Scale bar, 40 μm.

(D) iPSCs have been stained for the actin cytoskeleton (green) and the pluripotency marker OCT4 (red) with DAPI (blue) as nuclear counterstaining. Green arrows highlight apical actin fibers. The dotted white arrows indicate the direction of the grooves. Scale bars, 20 μm.