Human primary keratinocyte spreading on an asymmetric "arc"-shaped collagen I micropattern. The cells are stained for the focal adhesion protein vinculin (green, Alexa488), F-Actin (red, TRITC phalloidin) and the nucleus (blue, DAPI). The polymer brush micropatterning technique used is described in Gautrot et al. Biomaterials 2010, 31, 5030-5040. Images were acquired on a Leica DMI4000 using a 63X, NA: 1.25 and a Leica DFC 340 FX camera with 17 ms exposure for blue; 117 ms for green, and 159 ms for red.