Cell proliferation/motility. Some migration is noticeable as COS 7 cells shift in or out of the focal plane. Most of the original cells are seen to maintain their initial position and new cells are present (indicated by arrows). Scale bar represents 25 μm. The left image is after 4 days of incubation, and the right image is after 5 days of incubation.
Liebmann et al. BMC Biotechnology 2007 7:88 doi:10.1186/1472-6750-7-88