Fig 2: Effect of different endothelial culture media on quality of fpEC isolations. Immunocytochemistry for quality control of fpEC isolated in different culture media. Cells were seeded in chamber slides after expansion of first colonies. a fpEC were positive for the endothelial cell markers CD31 and VWF, with highest staining when cells attached very close to each other. b Contaminations with fibroblasts and smooth muscle cells were identified by positive staining for CD90 and SMA, respectively. For negative controls unspecific antibodies of the same isotype were used. Scale bar: 100 µm. c Overview of isolation success, i.e., % isolations without any colony outgrowth, % of outgrowth with contaminations, % of endothelial cell isolations that discontinued to proliferate and % of successful fpEC isolations, as revealed after expansion of the colonies and quality control by immunocytochemical characterisation. Contingency test (Chi square) of successful vs unsuccessful isolations revealed an overall effect of the media with a significance of 0.028. Data are given as % of total numbers of five (ATCC; VascuLife; Endopan; MCDB 131) or ten (EGM-MV; PromoCell; Cell Applications) fpEC isolations