This is a beautiful image of human brain cells, which can now be grown from adult skin cells.
Yichen Shi: Brain neural stem cells derived from human skin cells: these stem cells express typical marker genes of brain neocortical stem cells, such as Pax6 (Red fluorescent labeled), and form a rosette structure resembling the transection of the neural tube.
The entire image is about 250 μm across (a really thick bit of human hair).
Under the Microscope is a collection of videos that show glimpses of the natural and man-made world in stunning close-up. They are released every Monday and Thursday and you can see them here: bit.ly/A6bwCE
Explore further: X-ray tomography on a living frog embryo