Figure 1.

Nanofiber networks and the corresponding cell morphologies. A) Scanning electron microscopy images of 500-nm diameter fiber networks with bottom panel showing high-magnification images. Also shown is a schematic of the flat control substratum. B) Representative phase contrast images of cell morphologies obtained on the different substrata. C) Assembly of focal adhesions visualized by staining for the focal adhesion protein, paxillin (shown in green), and f-actin stress fibers in red and nucleus in blue. White arrows denote cell migration direction. In the case of the 54-µm fiber networks, cells exhibit no bias in direction of migration. Characteristically similar fiber categories are grouped as dense (3 and 6 µm) and intermediate (18 and 36 µm), whereas the 54-µm network is designated as wide. D) Cells of different migratory lineages behave similarly on fiber networks (example shown for dense network). All scale bars shown in µm. MSC, mesenchymal stem cell; SMC, smooth muscle cell.