Fig. 8. Confocal microscope images showing double immunostaining of microvascular endothelial cells for ß4 (red) and PECAM-1 (green). Each image is a maximum intensity projection image of a sub-stack of six optical sections taken from a larger stack of images collected at 0.3 µm intervals. The images were collected in the region just below the epidermal-dermal junction from sections of skin from adult (A-C) and P3 (D-F) mice. In the adult, almost all the vessels in this region showed immunoreactivity for ß4 and PECAM-1 (A-C, arrowheads). At P3, vessels expressing ß4 were rare (D-E, solid arrowhead), most lacked ß4 (open arrowheads). No vessels in this location showed ß4 immunoreactivity at P0 (not shown). Arrows indicate ß4 immunoreactivity on basal keratinocytes in the epidermis (e) and hair follicles (f). Scale bar: 25 µm.