Figure 4 .
TEM of the renal stem/progenitor cell niche after fixation in GA and ruthenium red. Low (a), higher (b) and high (c) magnifications illustrate the interstitial interface (asterisk) at the tip of a CD ampulla labeled by a cross (+). (a) Low magnification shows a broad ruthenium red label lining along the basal lamina of the CD ampulla. Also neighboring mesenchymal stem/progenitor cells exhibit a punctuate label pattern at their surface. The cellular protrusions (arrow) show a coat labeled by ruthenium red and line through the interstitial space (asterisk) up to the lamina fibroreticularis (L.f.) of the CD ampulla. (b) Higher magnification illuminates that a three-laminar structure of the basal lamina of the CD ampulla cannot be seen. Instead numerous cloud-like bundles of ruthenium red labeled material are spanning from the outer surface of the CD ampulla through the interstitial space (asterisk) up to the surface of mesenchymal cells. (c) High magnification illustrates that the interstitial space (asterisk) is filled with clouds of extracellular material after ruthenium red staining. Clear arrow head marks fibers at the lamina fibroreticularis.
Minuth and Denk BMC Clinical Pathology 2012 12:16 doi:10.1186/1472-6890-12-16