Issues

Primary cultures of dermal microvascular endothelial cells are composed by two different cell species of different origin: within a lawn of confluent endothelia homogenous cells, clusters are labeled by antibodies to the membrane mucoprotein podoplanin (red immunofluorescence), a novel specific marker for lymphatic endothelia. By contrast, the nondiscriminatory, pan-endothelial marker von Willebrand factor (green fluorescence) is expressed in both blood vessel and lymphatic endothelia. Taking advantage of its exquisite specificity for lymphatic endothelia, podoplanin was used to subfractionate mixed primary dermal endothelial cells by FACS into pure lymphatic and blood vessel endothelia. Primary cultures were established, and evidence for different, distinctive phenotypes of these endothelial cells was established. See related article in this issue by Kriehuber et al., pp. 797-808.